Corner Warping: 3D Printing Myths & Facts

Monday, June 10th, 2013

Let me begin by apologizing for the lack of pictures here… I will post some ASAP. However, I wanted to share some findings that have taken a good deal of effort to reach. There are lots of theories out there, and taking the time to test them is a brutal process. Some solutions to warping that are presented out there require altering your design… And I don’t like that at all. You shouldn’t have to compromise your part to prevent warping!

This brief post is meant to address corner warping specifically and debunk myths. The two myths in particular that I’d like to address are 1) enclosing the printer, and 2) printing faster…

1) I’ve finally gotten around to enclosing my printer. I’m glad I didn’t waste too much time on this… Because it doesn’t make a difference. I printed two parts… One without enclosing, and the other with. They both warped exactly the same amount. I must note that I didn’t fully enclose the top… But I could feel the heat build up inside… And had there been even a slight improvement… I would have gone the distance.

2) Printing faster is another myth… Not sure whose bright idea this is… but its kinda like trying to outrun a wave… Not going to happen.

So what works? Well, lets briefly look at what’s causing the warping. Think of each layer as a string with the potential for contraction. If the strings are cooling slowly and simultaneously (although at different stages of the process), then you can imaging them all pulling together and exerting more and more force on the part as the part gets taller and taller. If however, they shrink one at a time… They impose very little force on the overall part. So how do you get this to happen?

The simplest solutions… Print really slow! By slowing the print down to 1/3 speed… I took a part that was 4″x6″ by 1″ tall that was exhibiting significant warping, and eliminated the warping all together…without the use of a brim or mouse ears. Quite an improvement! I have started making different slic3r configurations which employ different speeds based on the part size. This has been a huge improvement.

Unfortunately, prints take a long time to print. That 4 hour print takes 12 hours. Big difference! But it comes out perfect. Alternatives to this might be to cool the part down as it prints with a fan, or ambient room temp. I will experiment with this and report back. Will need to see how this impacts the heated bed and the ability for the part to stick to the bed.

One other note in regards to this, I’ve found that printing external perimeters first is very important. Firstly, it often improves the finish of the part. Secondly, sometimes warping pulls layers apart slightly and if you run internal perimeters first, they are cooling while the external perimeters are printed… Which then experience the forces of those internal perimeter layers on them and sometime pull apart slightly… If you run the external layers first… They are contracting into the internal layers as they are printed and they don’t seem to pull apart at all. This last bit is theoretical… And not proven in any scientific way… Other than to say it helps!

I Love 3D – Part 3

Wednesday, June 5th, 2013

Part 3 – Advanced Applications:

It occurs to me that there is so much to discuss that this certainly will not be my last post on the topic. In addition, I’m sure the technology will change rapidly, and there will constantly be new things to share. And if you have anything relevant to share on this topic… you are welcome to share it here. Contact me via email and I’ll set you up!

Now, to continue…

In this post I want to discuss more advanced applications that I have engaged and experimented with, in addition to some new techniques, tips and tricks.

Lets start with some really cool new techniques, tips, tricks… Most of this revolves around what is referred to on various forums as an ABS Slurry or ABS Glue. It’s really simple and amazing. Lets start with a simple fact… Acetone dissolves ABS Plastic. It’s actually quite efficient at doing so. So you take acetone and ABS and combine them in a container (make sure it’s not an ABS container… that would be bad). Wait a bit and stir occasionally… and you get a liquid that is part acetone and part dissolved ABS. Now you can use this for various purposes…



Glue – use it to glue two ABS parts together… You have to give it time to fully dry, but its quite strong!

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Finish – paint it onto a printed part or soak the part and it alters the finish by both dissolving the perimeter layers of the part, and adding some of the ABS from the slurry. The effect is a glossy finish. In this photo the slurry was painted on…

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And in this photo the part on the left was soaked in pure acetone for just a few seconds. 20130604-175023.jpg

Stick – paint the slurry onto the printer bed and parts will stick like glue, which helps immensely in preventing warping.

For more tips, check back later for future posts “Pimp my Printer” and “AKS for 3D Printing.”

Now, onto the fun stuff! I wasn’t sure how broad to get when it came to advanced applications… as there are obviously so many different things you can do with this technology. In fact, recently doctors used a 3D printer to save an infants life (read article here). So anything I have to share clearly pales in comparison to saving a life! But there is something I am particularly psyched about that I want to share, and it certainly falls into the advanced application category. So let me break it down for you.

As I have mentioned previosly, parts are limited in strength due to the material and the characteristics of the way parts are printed… but I didn’t want to accept this fact… I wanted a way to use the printer to make strong parts quickly. There are other 3D printing techniques out there (such as stainless steel), but I clearly don’t have access to that tech… so I had to work within my budget and capabilities. This all began with a part I wanted to make… it was in fact a part I had designed years ago but never made due to its complexity. Here’s the part as seen in Solidworks.



This part was intended to securely hold a gyro at 45 degrees from the surface you were mounting it to, and my rod brackets and other mounting bracketry would allow you to precisely position the gyro bracket in 45 degree intervals, thereby placing the gyro at 45 degrees to two axis (such as pan & tilt, etc.)

Thrilled to have the ability to just print the part, I plugged it into Slic3r and printed it out. I was impressed how well it printed… but it was weak due to the nature of 3D printing. This weakness was inherent in the design, which required two load bearing surfaces to be at 45 degrees to each other. This places stress against the grain of the print, and the parts would break. I knew there was no way they were strong enough to hold a gyro safely. So I started working on a solution. I did spend quite some time trying to figure out if there was a better orientation to print in or mods to the part, but this ended up being futile. So what could I do?

Now my criteria was simple… find a way to make parts stronger without increasing production time or complexity, and thereby undermining the benefits of 3D printing. Obviously this would consume some time, but if successful I’d have a solution for the future.

So my next thought was perhaps there was a simple way to make a mold from the 3D printed part. So, I bought a product called Composimold which is a material that you heat up in the microwave, pour over your part, remove your part and fill the cavity with your cast material. The casting material I chose was polyurethane. It had a good hardness rating, and was machinable. It comes in two parts, which you combine and the cast hardens in about 15minutes. Simple, right!

Now, after playing with the Composimold I started to find it to be a little problematic to use other than for non-critical applications. So I started to rethink my strategy. I took another approach… using the cavity function in Solidworks I desgined the mold and printed it in ABS plastic.

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This worked great … or so it seemed. The mold printed great, and clamped shut well. I used a little silicone to seal the mold. So what was the issue. Well, I would say this approach is viable but removing the parts from the mold was a struggle. In fact, I was able to remove the cast successfully once, but after that I had to rip apart the mold on a subsequent cast and gave up entirely on a third cast.

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In addition, there was a big problem with holes in the cast part. In my first attempt I tried to cast the part with holes. That didn’t work. In my second attempt I tried to spot the placement of the holes, and then drill them out later. This wasn’t very accurate. I then started contemplating putting the part in the mill after casting it, and drilling precision located holes… but this started to sound time consuming and I felt like i was veering away from the spirit of 3D printing. So back to the drawing board!

Third times a charm! So I took another swing at this problem and I think I came up with a winner. This time when I printed the part I set it to print without any infill, which basically means it was hollow. This worked well.

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Then I simply drilled a hole in the bottom of the part and filled the hollow part with the polyurethane (the same two part casting material I used earlier). It worked GREAT! Now I had a quick solution. The part printed in a third of the time it normally took. Infusing it took minutes. And the end result was a really strong part, with precision located holes, and a finish color of my choosing. So, figuring I had a winning solution I moved forward in perfecting the process.

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There were a couple problems to overcome. First, I wanted a better way to fill the part. So I added two holes to the model and reprinted. Why two holes… one is to fill, and the other serves a dual purpose. The first purpose is to allow air to escape as the polyurethane filled the cavity. The second was to see when the part was full. After printing, I then drilled out the holes, progressively making them bigger, until the tip of a syringe could fit. Once that was complete, I did a wet test. This served two purposes as well… the first was to let me identify any leaks (which there were), and the second purpose was to determine how much polyurethane was required.

Leaks are always going to be present… this is because you are printing hollow, and without the infill the top side of the part becomes an overhang. The printer did a pretty good job, but you still get some gapping in the first or second perimeter layers which leads to leaking. I tweaked my design slightly to help with this… but some of it was unavoidable. So to solve this I located the leaks (which were always in the same place every time) and I applied a little silicone to them. This would be easy to remove later, and you really don’t even need to wait until its dry to proceed.

Now with my improvements I tried again, and it worked great. Parts were produced quickly with a lot of strength. There was a little work to do to clean up parts. Using a probe you can easily pick away excess polyurethane.

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Finally, if you so desire, you can gloss the finish of the part with a little ABS slurry.

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Quick Note: Polyurethane is an elastomer in the rubber family; it is not a plastic. Plastic and nylon can be compressed, and it does not return to its original size; polyurethane has memory. Also, plastics and nylons have a shorter life expectancy than any urethane, especially the hardest compound polyurethanes. We also exclude the use of Delrin in our mounts and suspension bushings due to its brittleness. Poly 75D has virtually the same hardness as Delrin, but is not a brittle material.

I Love 3D – Part 2

Friday, May 24th, 2013

Part 2 – Applications:

Before we get to the fun stuff… It’s important to point out the way in which 3D printing works, and the challenges to overcome when designing a part.

First, the printer prints in layers, and that impacts finish and strength. Here is a great picture that shows the same part printed in two different orientations. The one on the left was printed with the largest flat surface (the bottom of the part as shown) against the printer bed. The part on the right was printed standing on its end.

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Another issue is corner warping… Its one thing to keep the part stuck to the bed during the print… Another thing is keeping it flat and un-warpped. Due to the heat involved in the process, corners of larger parts tend to warp and pull up from the bed.

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This is challenging to overcome with some parts, especially larger parts with a large surface area touching the bed. One thing I’ve been doing lately is printing a large brim. This is a Slic3r feature… You can turn it on and configure it in the Slic3r configuration screen. I print a 12mm brim and that seems to help.

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That said, these printers (yes, I own two now) have opened up so many possibilities. Parts that I’ve wanted to make for ages, even ones I had already designed but didn’t start fabricating (due to the time commitment they would require), have been printed in hours as opposed to days.

Example… I’ve wanted for ages to experiment with a larger grip on my Ultra, and now my Ultra2. I’ve always liked the feel of the grip on the MK-V, XCS, etc. I didn’t have a design yet, but said “what the heck.” Let’s see how quickly I can tackle this problem. I took some measurements, opened Solidworks, and spent about an hour drawing the part. The design required two halves that would clamp over my existing handle. So I exported the two halves as STL files, and loaded them into Repetier. You can print multiple parts at the same time, so I positioned them on the bed together and ran Slic3r. Clicked a button and 4 hours later it was finished.

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I then installed helicoils, clamped it on, and added grip tape that I like. The entire process took about 6 hours (only two of those hours required my involvement). Had I made this part on my lathe and mill… It probably would have taken two days (with me there and present the entire time) assuming no mistakes. And if I got it wrong or wanted to make a tweak I would have been back to square one. Here, if I want to change something I just tweak the model and re-print… And if I need another one, the gcode is saved, so just click print. Here is the finished product… It works great!

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Another great application is for producing custom connector housings. Have you ever needed to make an adapter for a cable, but one of the connectors had to be a chassis mounted connector? This happened recently just prior to a ZipCam job. We use mil-spec amphenol connectors for our motor cables. I needed to make an adapter, but the female connector was only available in a chassis mounted receptacle. So I simply made a connector housing. Basically, it was a custom project box that came out of the printer with all of the mounting holes and clearance holes for the amphenol connector on one end, and a strain relief clamp and cable pass-thru on the other.

(Picture of amphenol adapter coming soon!)

Speaking of clamps, I have been designing a new mounting bracket for my gyros that incorporates a universal clamp accommodating 15mmx60mm, 19mmx100mm, 0.620×3″, and 0.620×2.5″ rods. This is an example of a part I had designed years ago, but never got around to making. The gyro mounting bracket itself has posed some challenges…but I’ll go into that in Part 3. Interestingly, I experimented with dipping the ends of this part in liquid rubber to see if I could get a better grip on the rails without as much clamping force. It worked great, but made adjusting the position in the clamp on the rails difficult since the clamp didn’t want to slide easily. I may however use this trick again elsewhere!

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I could go on, and on regarding all the fun and amazing things I made. Like this rose for my wife for Mother’s Day. The flower pot itself printed all as one, and the stem and rose printed as two separate parts that I glued together. The designs for this came off a website called Thingiverse.com which is a free, model sharing website. I love the concept, and I’m sure the selection of models is going to expand very quickly over the coming years!

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I’d like to finish up though with this more practical set of parts. Several years ago I had made a dovetail plate that slides onto the base of my sled and provides IDX mounting plate. The plate was not wired into anything, although you could use the PTap connector to provide power to devices. Alternatively, it functioned simply for additional bottom weight.

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I never got around to making more, even though I would have liked to, for a couple reasons. First, dovetails are very hard to machine. They are time consuming to get just right. Second, the clamping system was primitive and needed improvement. In this original design I simply used plastic thumbscrews that were driven directly into the dovetail. They tended to break eventually… It wasn’t pretty.

But now, with the 3D printer, I could easily produce dovetails. Once I got the dimensions correct I could pump them out. And I was able to improve the clamping design. In a matter of a couple days I produced several different plates. One set if plates had mounting holes for both IDX and Gold plates.

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Another set of plates were shorter and clamped a brass plate between them. On one side is a female dovetail, and on the other a male. This allows stacking. I’ve had this raw brass sitting around for years for this very purpose… And I’m not finally putting it to use.

(Picture of bottom weights coming soon!)

As you can hopefully see by now, the possibilities are endless. The speed in which parts can be produced, tweaked and perfected makes this technology ideal for our industry… And I’m sure it’s impact will be profound. In Part 3 I will discuss more advanced applications such as designing parts to overcome weaknesses in ABS and printed parts in general, rapid prototyping, and casting… Yes, casting!

I Love 3D – Part 1

Thursday, May 23rd, 2013

It’s been a long time since my last post and I’m so excited that my first post back is this topic… Cause I’m loving 3D! Not 3D cinema… 3D printing!

This all started thanks to my wife who, in retrospect, probably regrets forwarding me an article about gun legislation vs the new and inexpensive consumer grade 3D printers hitting the market. This article basically pointed out that new gun legislation is going to be ineffective since people will be printing guns very soon (and they are). But what really stood out to me was that this article indicated 3D printers were available as low as $500. Five hundred dollars!!!

This began my journey into the world of 3D printing. As there is SO much to share… I decided to break this post into 3 parts… Or you could say the 3 dimensions of 3D printing!

Part 1 – The Technology

Part 2 – Basic Applications

Part 3 – Advanced Applications




Part 1 – The Technology

There’s a load of information out there already… And I don’t want to be redundant. At the end of this section I will include a couple links for other information.

In this section I want to focus in a more subjective way on my experiences. When I started looking into 3D printing I saw that printers for consumer use were avail starting at $500 and going up to around $2500. These printers use a process of extruding ABS plastic in thin layers… It’s an additive process wherein two motors (X & Y) move an extruder, a third motor (Z) raises or lowers the table or bed from the extruder, and a fourth motor (E) drives a plastic ABS filament into the extruded where it melts and gets pushed out in very small amounts onto the table.

This process differs from higher end 3D printers which use stereolithography (laser into a solution that hardens when hit by light) or other proprietary techniques. Incidentally, a company called Formlabs just began shipping a desktop stereolithography unit for $3200. Although the precision is higher, the parts are intended more for rapid prototyping rather than use.

Back to my story… So I did some research and decided on a printer from Solidoodle. It seemed to offer the largest print area (8″ cubed) and the most advanced control from a software side. Price for the printer was $799.00. The down side is that there is an 8 week waiting period for a Solidoodle printer… So if you are anxious to get into this new world of printing… Place your order now or look at other manufacturers.

The Solidoodle printer is very basic… Not polished like some of the other offerings. It’s a sheet metal frame…not polished at all. In fact you have to be careful with the sheet metal… It’s sharp. I’ve cut myself a couple times. But a little tape along sharp edges will do the trick.

What’s cool about the Solidoodle unit is that they have used 3D printed parts in the design. Ultimately that is where this entire push came from… The idea of creating a machine that can self replicate. This is just the start.



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Getting Started:

My printer was finally ready to ship while I was on location in Chicago… So I had it shipped to the hotel. In retrospect, the housekeeping service must have thought I was crazy. The machine comes pretty bare bones with the printer, power cord, one piece of paper with instructions on assembling the filament holder, a sample bit of green filament, and a USB cable.

Now, the Solidoodle people are making a big effort to increase their support, documentation and videos…but you can imagine my surprise at the limited information in the box.

I’m obviously anxious to get started, so I dig in… and I don’t want to get too deep into my trials and tribulations… But there were definitely growing pains. I’ll go over this briefly.

The first hurdle I ran into was software. I found the Solidoodle site to be a bit outdated when it came to software. Here’s what you need to know about the software. First, you can print from either your Mac or your PC. In both cases you will need to intall the printer drivers (yes, even for Mac) and then install Repetier Host (whichever is the latest version). All of the software is free and independent of Solidoodle. I’ve used the program both on the PC and Mac side and they are pretty much the same.

Link for drivers
Link for Repetier Host

Included in the download and install of Repetier Host is a program called Slic3r. You can configure and run it from Repetier… So it’s pretty seamless. Slic3r basically takes your STL files (a generic 3D file that you can output from your 3D design program or download free from a site like thinginverse.com) and breaks them down into code for printing (this printer uses gcode… A very basic language for CNC machines… I use it on my mill). Don’t worry though… You don’t have to learn the code.

Here’s basically how you operate the software:
1) Open Repetier & click “connect”
2) Load the STL file (in PC version click “load” at top, in Mac version you need to select “Add STL” on the first tab.
3) Click the slic3r tab, select your presets, and select “slice”
4) Once its finished slicing you simply click “Run Job” at the top

As I mentioned you can tweak Slic3r settings from the Repetier app. Click on the Slic3r tab and select configure. This will launch Slic3r and you can start tweaking. The PC version comes with presets for Solidoodle which is nice… Not sure why the Mac version doesn’t but you can easily add these yourself. If you are using the Mac version, just try and get your hands on the PC version and copy all the settings manually. It would be nice if there was a presets file that you could just copy over… But this is not the case.

I’ve tweaked my settings a bit… But the most important tweaks to share would be to go to the section where you can add custom code and add the following… In the first field (for the beginning code) add “M140 S95″ and in the second field (for the end code) add “M140 S40″. This will tell your printer to turn the bed header on and set it to 95 degrees Celsius at the beginning of the job and then turn it off when done printing. I always manually turn my bed heater on ahead of time since it takes a while to heat up… But at least if you forget… this helps… And since I always print unsupervised, it turns the heater off for me at the end.

Perhaps the most common and pervasive issue people have is getting the print to stick to the bed. The model I purchased has a heated bed which is supposed to help… But doesn’t solve the problem entirely. The solution is a combo of: bed calibration height (z-tab); heated bed; and hair spray (yes, hair spray… Specifically Suave Extra Hold). Also, I’ve recently started rubbing some steel wool across the kapton covered bed just before spraying the hair spray.

That brings me to the kapton. The bed is covered with kapton tape. This is supposed to help adhesion of the part to the bed. However, when you combine the aforementioned tricks to get a better stick… It becomes very difficult to remove some parts. So much so that you have to use a putty knife to pry it off. And when you do that you will eventually destroy your kapton. The people at Solidoodle claim the kapton is NOT intended to be an expendable… But I don’t see how it can’t be. So I’ve gone ahead and bought a 6″ roll of kapton. It doesn’t cover the 8″ bed along one axis… But I couldn’t find 8″ rolls of kapton. I change it every dozen prints or so. Sometime less often.

Finally, one last hurdle. The printer kept clogging or jamming on me. By this I mean, the filament would stop feeding through the extruder. I spent days if not over a week troubleshooting this… And I finally figured it out. Let me preface this by saying I really like the guys at Solidoodle. They have been eager to help me. They have even called me on the weekend to help figure things out. I like their machine. I think it’s a great unit for the price. That said, I found that the filament I was buying from them was the problem. This might not be the case for other users, but I found it to be too soft. The gear that is used to bite into the filament and push the plastic through the extruder was ripping off bits of plastic and getting clogged constantly. No amount of tweaking would fix this. I realized this when I received a roll of filament I had ordered on Amazon from a company called Octave. The moment I opened the box I knew there was something different about it… And it printed perfectly. Since then I haven’t had to clean out the extruder gear once.



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Now, lets get to the good part… Printing in 3D! See above my first successful print ever. I took this to set and showed everyone. I was so exited.

Printing in 3D is amazing. It’s so liberating. I have a comprehensive shop in my house. A mill, lathe, bandsaw, drill press, belt sander, and a TIG welder. Probably spent $25,000 on it all. For $800 I have a machine that does it all… By itself… Unsupervised… In a fraction of the time it would take for me to fabricate conventionally.

Of course it is only plastic… So there will certainly be applications that require aluminum or steel. But there are plenty of things I had wanted to make that work great in ABS! And for those things that need to be in metal… To be able to prototype first in plastic is huge. I can’t tell you how often I spent weeks fabricating something only to realize I overlooked something… Then got mired in the process of salvaging the work (if even possible).

Keep in mind, it is only an $800 piece of equipment. And as you are all aware… You get what you pay for! Some of the drawbacks are as follows:

1) Since it prints in layers, the parts are weaker with the grain than against the grain
2) Overall, keep in mind the tensile strength of plastic is significantly less than aluminum
3) The precision is only 0.01 roughly.
4) The finish is only smooth on one surface, the surface the is against the bed. The rest of the surfaces have a ribbed finish.



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That said I’ve done some amazing things with it. Here is a list of must haves to compliment the printer:

1) Most important… Hair spray (suave extra hold)
2) Helicoil set… This is critical if you want to install any tapped holes. You can tap the parts without helicoils, but they wont be very strong. Helicoils aren’t cheap but god it works good!
3) Acetone, which melts abs, is useful for cleaning
4) Alcohol for removing the hairspray from the bed
5) Filament obviously
6) Putty knife for removing parts
7) Roll of kapton

In the next part I will get into describing the applications for which I’ve used the printer. Stay tuned!

HP Video’s HD-SDI Transmitter

Tuesday, January 10th, 2012

HD video transmission is upon us… and there are more and more solutions available every day. The question bears asking… “Is the Steadicam Operator still responsible for transmitting video?” 20 years ago Steadicam was one of the only modes of operation that required being wireless. Today, not only are there new support options that warrant or require wireless transmission, but the availability of wireless tech makes almost every other mode of operation easier. With that… productions are equipping themselves with camwave’s, boxx meridian’s and other solutions right out of the gate. So are we still responsible?

If we are still responsible… how good of a system do we need to provide? There are systems out there for hundreds of dollars… and then there are systems (like the Boxx Meridian) that cost upwards of $18,000.

In the pursuit of the answer, I did some research and found a product by HP Video. Their big claims are:

- 5.1-5.9 mhz range
- similar range as the Boxx
- transmitter the size of a Modulus with only (2) antennas
- free / built in Marshall monitor
- uses the same connectors as the modulus
- range 200-250 ft line of sight, & 100-150 ft indoors
- price tag of $7500

In addition, they back their product with a 3 day trial – no questions asked. So we gave it a try.

I found the system to be built well. Indeed it’s a nice compact package. I’m not sure if it is truly as small as a modulus, but its close. The unit does indeed use the same 6 pin Hirose connector found on the modulus, but the connector on the HP Video transmitter is only wired for power. You have to input your SDI signal through the BNC input. This is a little inconvenient since all of our modulus cables are wired to carry both power and signal. Plus many of our support systems (including our ZipCam) are wired to output video and power on the same connector. So that was a little disappointing… but not a deal breaker.

The receiver has a built in Marshall monitor. It’s a nice display, and great for carrying around… but as a stand-alone receiver, I’m not sure if its that convenient to have the monitor built in. The unit is a little awkward to mount anywhere. It might be better if it came with an adapter for a c-stand’s 5/8″ pin. We placed it on a table and found it to be a little unstable. Also, there’s no way to input a video signal if you wish to use it as a monitor only.

Finally, there’s the issue of performance. Let me first say that we tested the system with our ZipCam System, which is a point-to-point suspended cable camera system. We tested it outdoors in a field, with very little reflective surfaces nearby. With that said, the range of the signal started to break up at approximately 100′ max. In addition, we mounted the transmitter to the base of the head, so at times it was blocked slightly by the camera body or other parts of the head. In these instances the signal broke up much faster and was very unpredictable. Unfortunately, once the signal is lost it takes quite a long time to reconnect. HP video claims (I believe) 7-8 seconds. This made the system quite unusable for our purposes since we operate the camera from the transmitted image.

On the flip side, picture was sharp & there was <1ms latency. I would have liked to have tested it for Steadicam purposes on a stage or location, but since it clearly wasn't a match for our ZipCam, we decided to return it. If anyone would like to share their experience, please feel free to add your comments to this entry.

Tiffen Service: Turning a New Leaf?

Friday, December 9th, 2011

Tiffen historically has had a pretty bad rep when it came to service. Not to name names, but I think this had a lot to do with personel that was previously employed there. In the past few years, service has been handled by Michael Craigs, and service has improved dramatically. Turnaround on parts is quick, and if not they always seem to have a loaner. And they seem to have become pretty reasonable with their fees. So I’m here to say… If their device reputation was the only thing holding you back from buying a Tiffen Steadicam product… You might want to give them a try.

For the record, this entry was in no way solicited by Tiffen. Just thought they deserved some credit.

Ultra2 & 12V Cameras

Monday, September 26th, 2011

Let me begin by saying that most of what I’m about to write about could have been avoided if I had just read the damn manual! But who reads manuals anymore?

I am a relatively new owner of my Ultra2 Sled. Bought it back in December of ’10, so I’m about 9 months in. On one of my first jobs I was flying a RED. I thought to myself, why don’t I just use the rig in 12v mode. Unfortunately, I got very little run-time in that mode. Hmmm. I had two PowerCubes on there… should be getting better performance. But, I’m at work. No time to diagnose… just switch over to 24v mode and let the down-converter do the work. Viola, better run time on the two batteries.

Then, a couple months pass, and I’m back on another job with the RED. This time I can’t even get the rig to boot properly in either mode. Camera gets 50% through booting and dies. Weird! So, again, no time to diagnose, just slap on the camera battery and go!

Now a couple months go by… in the meantime I’m flying the Alexa a lot. Back to a job with the Red and again, camera not booting. Here I have a bit of time so I decide to figure this out. I start trouble shooting and realize that if I power the monitor via 12v the camera dies during boot up… if I go with 24v, then it makes it through boot up. Hmmm. Guess what else is happening!?!? The battery bracket is getting scorching hot!

So, its pretty clear what’s happening… the RED pulls so much current that its overworking the 24-12v down-converter. It in turn is getting VERY hot. AND if you add the stress of the addition current demand from the monitor (if you connect the cable so as to power it off the down-converted 12v source) then you officially hit the limit and the camera shuts down.

Great, now I know what the problem is, but how do I fix it. Here are a couple answers to that question which might benefit others!

1) Its important to note that out of the box the Tiffen Steadicam Ultra2 is configured as follows: Switch the unit on in 12v mode (indicated by | on the switch) and you are ONLY using the rear-most battery in 12v mode. Switch it on in 24v mode (indicated by || on the switch) and you are now using both batteries in series – giving you 24v and implementing the 24 to 12v down-converter which is housed in the battery bracket. My guess is that this down converter maxes out around 8 or 9 amps… so beware. HOWEVER, if I had only read the manual I would know that I could configure the unit in 12v mode to use both batteries in parallel. This is done by removing the battery plate closest to the post and swapping around some cables (see your manual for details). This effectively eliminates the 24v mode, but sure does solve the problem described here! Only pain is that you have to open the unit up to switch back and forth. Shame they didn’t build in a switch… will work on a solution for that.

2) Another alternative that I implemented and like is to use the IDX E-HL9 batteries instead of the PowerCubes. These are essentially the same exact guts as the PowerCube, but have the ability to stack onto one another. So what I’ve done is to switch the rig into 12v mode, and just place two stacked batteries on the one active battery plate. It does essentially the same thing as achieved by the procedure mentioned in #1. Furthermore, you can combine these two solutions and fly 4 batteries at a time! I’ve done this when flying gyros.

So I hope this has helped some of you that were also scratching your heads about using power hungry cameras like the RED with your Ultra2 or other similar Tiffen model.

Gatorade “Go All Day” Steadicam Shot

Thursday, September 15th, 2011

TheBerrics.com recently posted a video sponsored by Gatorade featuring Chaz Ortiz, a 17 yr old skateboarding phenom. I was given the honor of operating, and it turned out to be some of my proudest work. Thank you to TheBerriks.com and thanks to all of the operators in the Steadicam community that took notice and have shared their thoughts and kind words.

We shot the video essentially MOS with a scratch track. We used the AWESOME Arri Alexa and with an Optimo 15-40 zoom… although we did not zoom at all in the video. I flew the camera on my Ultra2 with an MDR2, CamWave, and a pair of Ken-Lab KS-4 gyros powered off my own custom made gyro inverters.

The biggest factor in the success of the video was that the producers realized we needed time to pull this off. I think less seasoned producers would have pushed for a 1-day shoot. Fortunately, they understood the complexity and we had 2-days to make this happen. For those of you that might not have guessed, the video was shot in 3-pieces (2 cuts only). The two cuts bookend the time-lapse section… but I will get into that more later. The three sections were “Arrival,” “Time-Lapse” and “Skateboarding.”

So, since we had 3-sections to shoot, we spent Day 1 rehearsing & shooting the more complex section… “Skateboarding.” We figured that if something went wrong, it would be in that section and we would have Day 2 in order to resolve the problem. Day 2 was spent first rehearsing the first section of the video, “Arrival.” We then shot the “Time-Lapse” section, and then shot the “Arrival.”

Now there’s never enough time, but I have to say it was nice having as much as we did. The AD would work with the extras for the first couple hours of the day to work out a rough blocking. Meanwhile we were setting up the camera, discussing the days schedule, etc. Then we would spend a couple hours walking through the section we were shooting that day. No camera! Just working out logistics. This obviously included the shot and blocking, but we had to also consider communication with extras for cues, vehicles & safety (more on this later), and coordination of a spotter, my AC, the DP, and at times the AD.

Once we were satisfied we had addressed every detail, we started running through it with the camera. We would walk through the shot, piece-by-piece, stopping and starting to make minor tweaks to blocking until we had it down, and then ran through a full pass or two. When we came back from lunch we had specific things to tackle each day. On the first day we had to give Chaz time to practice his tricks. The ones in the hallway seemed like cake for Chaz, but that giant rail slide was a different story. It took about an hour for Chaz to warm up to it. It was amazing to watch. He approached it very meticulously. He first took a couple dozen approaches to it stopping right before the rail. Once he was finally ready he took to the air, and didn’t quite get it… but I’ve never seen any one take a fall so well from that height. That was it… after that he was a machine.

While we were actually shooting he did 10 takes in a row without fail… it was amazing. What was even more amazing was he had to wait at the top of the stairs while the shot continued, listening to the marching band playing, and waiting for a cue to go. Not the ideal scenario for prepping yourself for a big trick like that. Nonetheless he was a champ! We did 11 takes (I think), and he only fell once.

On day 2 we shot the “Time-Lapse” section between rehearsal of and shooting the “Arrival.” This was done with a lock off camera, but during one of our tech scouts I suggested that I shoot a minute or two of the hallway on the steadicam (without anyone in the frame) and that the visual effects person map the “float” from that onto the finished time-lapse footage. They loved the idea and it worked great. It really sells the move as a single take.

“Arrival”

The “Arrival” was shot on day two. It was certainly the shorter and less complex of the two. What was lost in the edit was that we actually built a platform on the front of the car Chaz is arriving in and drove for a couple hundred feet at the head and tail of the shot. Then stepped on/off the platform as Chaz got in/out of the car. Problem was there was a lot of time killed in the slowing down and stopping of the car. I had suggested a crane step on/off instead, but I think budget was prohibitive. So in the edit they just cut out the gimmick… oh well!

The stairwell inside the school was of course challenging. I didn’t want to just follow or precede the entire way. I find this so boring. It needs to move the story forward or there is no point. I also had to consider the two or three others from the crew that were following along to make sure they weren’t in the shot. We knew we wanted to start the stairs following, and end preceding… at least that’s what the director envisioned. But I wanted to make the transition at the first landing. So I worked with the director to come up with an action that would allow this to happen. This is where the two girls came in (one of which was the daughter of our focus puller Al Cohen). The girls toss some paper at Chaz, this draws our attention over to them, which in turn allowed my AC, DP & AD to pass camera left. Once they were on the landing, I used the girls look to draw camera back to Chaz. This allowed the crew to get ahead and above me on the next set of stairs, which I climbed walking backwards if I recall correctly.

After this, it was simple stuff. Chaz puts skateboard in locker and goes to class. Of course I had to land and lock off on the same mark each time, at the same lens height, with the same tilt. To do this, we set up the end frame before rolling either the “Arrival” or the “Skateboarding.” Then we placed an apple box on the mark with a furniture pad on top of it, and of course marked it like crazy in case it moved between takes. During the arrival I used the pan at the very end of that segment to hide a very slow boom down. This was in order to kiss the bottom of my rig down onto that furniture pad…which told me I was at the right height & position. Then I held the shot locked off for about 20 or 30 seconds. At the beginning of the “Skateboarding” section I started with the rig just barely touching the furniture pad and floated away. We were able to get the camera within an inch or so every take… and this was acceptable for visual effects to stitch the shots together.

We did 11 takes. In my experience on these long takes… take 7 is the one everyone nails… then it kinda goes to crap for some reason for a couple takes, and then everyone finally nails it again on take 10 or 11. That was of course the case here… we nailed both “Arrival” and “Skateboarding” on take 7, then again on take 10 or 11 which was the last take we did for each. Once we had two keepers we went home.

“Skateboarding”

The “Skateboarding” section is probably the more interesting section from a technical perspective. Again, I started the shot with the camera floating just above a furniture pad, with the post over the mark we set for the end of the time-lapse. The camera then floats away as Chaz sneaks out of class and heads to his locker.

The stairs again posed a challenge. The client (Gatorade) was not too aggressive in getting product shots… but they did want some visibility. In all, we have Chaz drinking from the Gatorade bottle twice, a Gatorade water bottle sticking out of the basketball players gym bag, and an orange Gatorade cooler carried through the background right before the rail slide. So they were pretty hands off. However, this was where we needed to show Chaz drinking from the product. So we needed to be in front of him going down the stairs.

I took the first set of stairs in Don Juan with my crew just below me on the stairs. Then they all tucked against the wall as I switched out and followed Chaz down the second set of stairs. We needed to follow down this set of stairs so we could establish a trash can at the bottom of the stairs that he would stop at and throw out the bottle. However, this made it really tough on the crew. They got stuck behind me going down the stairs. So when we reached the bottom they needed a way to get by. We were already working with a tight space and close to minimum focus on the lens. So at the bottom of the stairs I had to play it just right to stay outside minimum and leave just inches for three people to clear (my AC, DP & AD).

After they cleared they flew out the door and loaded onto a golf cart. Many people suspected a segway, but this would have been tough (but not impossible) to step onto… AND, you have to remember I have three other people with me. So instead, the key grip (Gus Vasquez) built a platform on the front of a golf cart just inches off the ground which made the step on/off really nice.

20110915-035241.jpg

I worked with the directors to create a beat for the step on… it made sense anyway that since he was sneaking out of class that he would pause to check if the coast was clear. Then we chased Chaz as he nailed the three tricks in the hallway.

As we approached the third trick, Gus and I worked it out that so that he would slam on his breaks. This essentially propelled me off the golf cart at the speed it was moving and I continued the chase for the next 100’ or so on foot. This gave Gus enough time to throw the golf cart in reverse and back up beyond the bend in the hallway.

Finally, the big trick. For me, there wasn’t much to it… I just needed to make sure the camera was pointed in the right direction. I would have felt terrible had I missed even one take. Sure enough I was in place for every one!

The original vision for the shot at this point was to then follow Chaz as he walked across the school lawn back to the car that was picking him up. For logistical reasons I thought this was going to be difficult, and not really pay off. So I suggested that especially at this moment of climax it would be so extremely cool if he hit that rail, landed and walked a couple steps right into his car. Colin & Steve weren’t sold, so I showed them and sold the idea. I think it really punctuates the video nicely.

I’d like to give credit to TheBerrics.com for having conceived such an application for Steadicam. TheBerrics.com is owned by a couple skateboard legends, one of whom is Steve Berra. Steve is not only an accomplished skateboarder, but a gifted filmmaker. His film “The Good Life” with Bill Paxton was featured at the Sundance Film Festival in 2007. I’m not sure if the shot was Steve’s idea (Steve acted as EP on the job), or the director’s, Collin Kenedy… but nonetheless it was a cool idea to approach a skateboard video this way! I got involved with the job through Patrice Cochet, the DP for the spot and whom I’ve worked with for years now. He was the cinematographer on Steve Berra’s Sundance Pic.

Thanks to all those in the Steadicam community for taking notice, and for your kind words regarding this piece.

Exploring the 3rd Dimension – Part 1

Wednesday, May 11th, 2011

I’ve recently began my study of 3D. At first, I must admit, I was a bit resistant to 3D. I probably used all of the cliche arguments. I am, now, warming up to it for a few reasons. First, I’m discovering that there is truly an art to 3D cinema, and that it’s not just a gimmick. There are quite a few good and bad examples of 3D out there. Having seen enough of both now, I can truly say that I do enjoy watching good 3D!

The second reason I’ve warmed up to 3D is because I believe it’s here to stay. From a financial standpoint, any movie released in 3D makes more money. And the people that make decisions on what we shoot are the money people. So if you can’t fight ‘em, join ‘em! With that, I’ve decided to embrace the new trend and learn as much as I can about it.

The first thing I did was participate in the ICG Stereoscopic Workshop at the Sony 3D Technology Center. This workshop is free to members of Local 600 and is well worth the time. It doesn’t focus too much on the technical aspects of 3D, but more on the aesthetics. You learn the vocabulary of 3D… and boy does it open your eyes up to a new world.

Since the workshop I’ve been trying to watch as much 3D as possible. I realize that I need to be able to understand 3D as well as I understand 2D Cinema. Most recently I saw Thor in 3D (which was converted from 2D), Hoodwinked (which we only made it halfway through) and Rio (which I had previously seen with my son in 2D and was excited to compare the experience in 3D). Without making this into a movie review, I’d like to comment on things I’m learning about 3D.

1) Thor & 2D Conversions – these really don’t work for me. It just reads like a bunch of cardboard cutouts placed in space. Of course, all of the CGI is rendered in true 3D… but anything acquired in 2D looks odd. Plus, the lens choices were made for 2D, but when converted, I believe it forces post production stereography to make compromises with inter-axial settings that just don’t work for me. Basically, many over the shoulder shots and even shots where two characters were having a conversation in the front seat of a car, felt like the actors were much further apart than geography would dictate. I hope this trend ends and we start seeing studios make the call to go 3D earlier on in the development of projects. I can’t believe its a good financial decision since it costs $8,000,000 on average to convert a movie and you end up with a sub-par product.

A big challenge that I’m beginning to notice is that extreme wide shots that include people, or animals, just don’t work well in 3D. The people and/or animals begin to look like little models in a diorama. Its really weird, and I saw examples of this in every movie I reference here. I suspect that the filmmakers are choosing an interaxial that is way too big in an effort to make this ultra-wide shot look 3D. Past 30 feet or so, we can’t see 3D. Everything becomes 2D… but we are able to use our knowledge base to determine distance to objects beyond that point. However, I think filmmakers are insisting every shot have as much 3D as possible. So they widen the IO and this changes the relationship of space to size of objects beyond the point we are comfortable with and things begin to look “wrong.”

2) Lighting in Theaters – make sure that the theater turns the overheads off completely. I was in a theater and they left the overheads on, but dim. It wasn’t until about halfway through the movie that I realized why I was having so much trouble watching the film. The overhead was flaring either the left lens of my 3D glasses or my left eye. This was essentially causing an iris mismatch between eyes. This is one of the violations you want to avoid in making, and watching 3D… it makes it very uncomfortable to watch. Once I repositioned myself it was fixed. So if you are in a theater and they don’t turn the overheads off completely… complain! Damn you Regal Cinemas! Where’s an ArcLight when you need one!

3) Hoodwinked (into going to this movie) – besides the movie being pretty bad, so was the 3D. Actually, I take this back… I’m not sure the 3D was that bad… it just didn’t work for this picture. Hoodwinked uses a rather simple style of animation. Definitely not photo-realistic in any way. Feels a bit like the “Far Side” comics… which I have no need to see in 3D either. Probably a bit lax on the textures. So it seemed a bit silly to me to see it in 3D. I suspect it works much better in 2D.

One very interesting thing they tried, which didn’t work for me, was a split screen. This 2D convention just doesn’t work in 3D. Perhaps had they framed the split screen to make it look a bit more “fish bowl” like, but this particular execution doesn’t offer too much encouragement. With that said, I’m not a huge fan of the effect to begin with.

4) Rio – This picture was surprisingly good in both 2D and 3D. I wasn’t surprised it was good, just that it worked well for both! I have to admit, out of the three movies I saw this weekend, I think I learned the most from Rio… but to point out just a couple things…

Dissolves don’t work for me in 3D. Or perhaps the ones I’ve seem are odd. In 2D we are dissolving two, flat images over each other. It works. In 3D, we are dissolving between two spaces with different depth. We could be going from a close up of a picture frame on a night stand, where there’s virtually no depth to the shot, to a wide shot of an expansive room like a church. Ultimately, the dissolve forces these two volumes to fit into each other… its a bit odd! Maybe it just requires some serious storyboarding and planning to be sure the two shots will compliment each other.

And finally, volumetrics. This refers to things in the air that define space like smoke, fog, dust, etc. These are hugely important for defining the 3D world and providing depth cues. However, what I noticed while watching Rio was how amazing volumetric objects looked… not sure if I’m using the correct term here, but I’m referring to things like glass. Objects that have volume, but are transparent or translucent. It was amazing having watch Rio in 2D where I didn’t notice the rendering of glass at all, to 3D where all of a sudden glass just popped! It suddenly had volume and dimension. It was almost as if they couldn’t “dumb” down the glass to match the animation style. Perhaps this is a characteristic of any transparent solid in animation… as soon as its given a 3rd dimension it becomes photo-realistic! Regardless, incorporating glass and reflective surfaces into 3D in both animation and live action is a must!

More to come in Part2…

Cut, Polish, & Finish

Thursday, May 5th, 2011

No, I’m not talking about anything to do with filmmaking! I’m actually talking about fabrication. Many Steadicam Ops (myself included) have gotten involved, to some degree, with fabrication of parts and/or equipment. I must admit… its a blast! Seeing that shiny new part in use is quite a high. But of course, if you end up with a heap of junk… you’re note going to find yourself receiving too many compliments. So what’s the key to making good looking parts?

The first is a good cut. This is too complex for just one blog entry, but if you are cutting the part yourself you need to be sure you:

- hold the part well
- use the right machine for the job
- use the correct cutting tool
- set the machine to the proper RPM’s
- use cutting oil when appropriate
- feed the part or cutting tool at the appropriate feed rate

It’s taken me quite some time to figure it all out… and to be honest, I am still learning. It’s a bit Zen! Your best bet (if you are doing it yourself) is to buy some books, rent a video, and or google as much as you can on the topic. AND BE CAREFUL!

Second… Polish! This is so important, and seems so obvious, but the key is how… STEEL WOOL! Even a great cut, which produces a pretty good finish, will benefit from a little polishing. What most novices don’t understand is that the bright anodized finish they see on camera equipment results from anodizing a shiny part. Anodizing does not inherently made a dull finish look brighter. It’s not glossy paint. If you have a dull, ugly, matte finish… anodizing will just make that same finish black (or whatever color you choose). So you need the brightest finish possible before sending it off. The key is Steel Wool. Buy yourself a bag of coarse, medium and fine wool. Then go at it.

Finally, the finish. This is the key to making your part look professional. I have to admit, I don’t always do this myself. Often times its because I’ve installed electronics in the part that would require a ton of work to remove, or because I’ve put a part into use right away, and remembering to pull it out and send it in is a challenge. Another issue is that any plating company you hire to anodize or plate your work will chart a batch or lot fee. This means it will cost the same to process one piece as it will to process a couple dozen (typically about $75). So you want to send a bunch of stuff in together. This is difficult seeing as you probably won’t have a bunch of things ready all at once. So you’ll start using some, and then forget to get them plated.

Here are some things to remember when getting your parts anodized or plated:

- plating companies charge a lot fee… so save your parts up and do them all at once
- try and use the same alloy for most of your projects… you’ll pay a lot fee for each alloy (I like aluminum 7075)
- if you’ve been using the part and the finish is dull, hit it with some steel wool before sending it off