31 replies to this topic

[tjallen]

Neils,

Yes, the yellow chassis is the Shapeways Yellow Polished Strong & Flexible Plastic.

 

The plastic looks fine for a static application, but in my jail door design, this plastic is too flexible for a runner. In the image, I twist the chassis almost 90 degrees, and I could probably twist more, but I do not want to break it. With this much flex, the motor will twist itself away from the gear, or maybe the motor will droop and contact the track.

 

 

 

On the other hand, the chassis integrity is high. As you see, twisting does not damage it. I have dropped it several times from about 4 feet - it bounces around!

[munter]

Because the material is lightweight perhaps you could add structures that counter the flex...kind of spaceframe style.

[tjallen]

Alas, my quest for a Shapeways 3D printing material appropriate to this application continues unfulfilled.

 

We can mark the material called "Black Acrylic" as too flexible. The material is also too brittle, as I cracked it during the flex test. And it came warped, although maybe I can fix it with hot water. That is unfortunate, because this material had the best finish of all of the materials I tried so far.

 

 

 

A further note: As of this week, Shapeways has discontinued this black acrylic plastic, and several other materials. Maybe I will have to be looking at other 3D printers and other venues to offer my items. That is, if I ever get one that works.  :-)

[Dennis David]

See if you can have it done via SLS (Formlabs) using Grey Pro Resin.

 

[MSwiss]

I admire your work, but I'm not seeing this as a runner, and hoping Shapeways was going to come up with an appropriate material, seems totally unrealistic.

The pic in my post 13 is an example of the thickness required to aggressively run a 1/24 chassis, without constant fear of breaking.

That chasis was redesigned after parts of it, when originally thinner, were breaking.

You are taking a chassis, designed for metal, and trying to make it work in plastic/resin.

124 hemi, on EBay, sells complete cars with real jail door chassis, by the dozens, if not hundreds, for $75 to $100.

Again, great work, getting the CAD work done.

[brucefl]

If you come up with a way to easily machine ceramic, please share.

yeah Mike the dentists cad cam machine for dental crowns,they cost around $70,000.and use blocks of ceramic only big enough to make a crown,but maybe outside of dentistry they may have done something I'm not aware of.

[Dennis David]

5-Axis Wet/Dry Dental Mill

 

https://mode-smart.c...-4/products/dc1

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