# Form 2 Corner to Corner Max length

I own a scale modeling company and have recently purchased an antique 1800’s collar crimper. It has brass crimping rollers that can be replaced. I want to print new ones to make scale corrugated aluminum roofing material out of .005" thick sheet aluminum.

The rollers are 1-1/4" in diameter and 7" long. I figure these should fit, one at a time, orientated lower left corner to upper right corner. Has anyone come up with the maximum dimension that way on a Form 2?

a = width b = depth d = height
a^2 + b^2 = c^2
c^2 + d^2 = your anwser

145^2 + 145^2 = ~205^2
205^2 + 175^2 = ~269.5^2
269.5mm = 10.6in is the theoretical maximum length for a straight line print in the form 2

Thanks, that’s close to what I figured it would be using a tape measure in hand. My parts will easily fit in that.

Now to the engineering of the pieces. They have to mesh and the scale is small. I’ll just make one design and then duplicate with the different shafts needed. Since they aren’t geared the corrugations on the roller do that. I’ll be forming .005" thick aluminum pieces.

Remember that 10.6 is for the center of object that’s aligned corner to corner. Consider the difference between a tube shape that’s 1/2" diameter oriented corner to corner vs. a tube that’s 2" in diameter. The center of the object isn’t what matters, it’s the corners furthest from the center that matter. those corners protrude outside the build volume. The larger diameter the roller, the shorter it has to be. And you need a base and supports.

I have the trigonometry skills to figure this out, but it’s late and I’m too lazy. Easiest thing to do is import the object in to PreForm and see if it fits, no?

Randy, Yes, I understand this. The object is cylindrical and 1-1/4" diam. by 7" in length. Well within the 10.6".

Here’s a photo of the equipment and the brass rollers are what are to be replaced with resin printed ones. The serrations will be much finer so my real concern is slippage between the two.

Here’s a screen print of the 3D drawing of the Top Roller actually. The bottom is the drive roller. I still have a bit of work on this but it’s close to being printed.

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I printed these overnight, 10 hrs. and they turned out great. I was able to do both rollers in the same build. They are in the UV hardening oven right now. That’s a towel sanitizer as others also use.

Looking forward to seeing the final result, both the print and the bent aluminum. Which resin did you use?

Well, I’ve back burned that project. I did get the rollers printed. Took 10 hours. But found a few issues I need to address. One end of the rollers run on a hole in the end of the shaft while the other end runs on the outside of the shaft. That end was a bit undersized and the rollers weren’t tight causing the aluminum to screw in a turn. Last the design of the corrugation in the rollers is twice the size it should be. That was done by a friend in South Carolina who love O scale. [grin]

I’ll fit the machine back together and put a piece of aluminum through and take a couple of photos and post them.

OK, here’s a couple of photos of the Crimping Machine. First with the rollers out and the second with them in. The sheets of aluminum have already been run through it. As you can see it has a tendency to scew the pieces as they go through. These have been through two or three times trying to keep them straight. The crank ends of the shafts need to be enlarged. Also a add-on piece is needed for the crank roller to get the crank out far enough to clear the table clamp. The roller would be too long to print so that is a third piece needed.

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