Upper Cab to Door seal project

[MightyMike]

Hi Tom - trying to order the same but couldn't find the items using the Shapeways search box. Would you please point me in the right direction. Thanks!

[Angry_Truck]

OK TPU Prints are on their way! I'll post when they arrive! Again thanks Brian!! Oh and Brian .... do you have the STL files for the rear door/cab seals????

Attachment 3451

Teking -
I didn't make any CAD data for the rear seals because of the way they attach to the cab. The rear seal is overmolded over the metal bracket which mounts to the cab. That bracket would be too flimsy if it was 3D printed.
It had to be made by making a pattern, then a mold, the overmolding the rubber on top of a metal bracket.

[jeepdan]

I also wanted to see if I could re-make the seal at the top of the door frame. This one turned out to be a real hassle. It is an odd shape, it has a weird, overmolded metal bracket with tabs on different planes - in general, a troublesome part. I wanted to make it a little larger than the original, which would allow for some "tuning" by material removal once I had it fitted to the truck.

I tried making a pattern several ways and then ended up taking some modeling clay and smashing it in the door:




This gave me some idea of the correct shape, and I then morphed that shape with the original to make my pattern. The pattern is some polymeric modeling clay, epoxy, and styrene sheet:


A silicone mold was then made around the pattern. This took me several patterns and molds to get right.


This picture shows the bottom half of the silicone mold with the overmolded mounting bracket, ready for urethane.


Picture after urethane, ready to be removed from the mold. This part ends up with a lot of flash and extra material due to my sloppy mold technique, but it cleans up ok with a little work. This picture shows one of my earlier attempts, and you can see the bracket poking through the material. I tuned that with some later shots and the bracket is now buried about 1/2 way into the seal.


New part on the truck (the old round bumper is in the background). Like I mentioned before, it is a little larger than the original, so I can sand away a little material to get it to seal well on the door frame and door.

Great work! Can you provide links to the materials that you used in making of the rear bumpers? I would like to try making a few rear bumpers for my truck, but rubber casting is new to me.

[Angry_Truck]

Jeepdan,

I used products from Smooth-On. There may be others out there but these seem to work well for me.

The molds are made from "Mold Star 30"
https://www.smooth-on.com/products/mold-star-30/
The trial size is more than enough to make a mold for the bumpers.

The parts are made from "Vytaflex 20":
https://www.smooth-on.com/products/vytaflex-20/
I tried both the 20 and 30, the difference being the hardness of the final part. Subjectively, it is very hard to tell the difference, so you might just see which is cheaper.

I bought my stuff from Amazon but the prices have gone way up recently (especially the Vytaflex).

The overmolded metal backing plate is a penny that I drilled a hole through. Cheaper than a washer!

[teking]

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