Thermoforming and mold making (1 Viewer)

[TheDeparted]

Anyone here have experience with this? The basic ideas are really simple, of course, but I want to make a mold of a car seat bottom and can't really figure out how I want to go about doing this without damaging the seat (and retain quality details like the pleats).

I don't have a 3D scanner or a 3D printer. But if I did, that would be awesome.

Right now I'm thinking about getting some very thin ABS or other thermoforming plastic to make the initial cast and filling that with clay or concrete or something to make the working mold. The thinking is that the thinness of the material will limit the exposure of heat to the seat material. However, I'm slightly concerned about the plastic sticking to the seat or otherwise transferring oils - so I'm not sure if I should use anything between the plastic and the seat or not...what would fit tightly enough to the seat to allow details to be imbued without providing its own "details" like crinkled aluminum foil might do? All-purpose flour?

 

[The Mongoose]

Optimus is your robot. And bob's your uncle.

He knows about this stuff.

 

[Bleu Raeder]

Is the car seat bottom cloth?

 

[Saint_Ward]

What's the end purpose?

Thinner material just means it will get to temp and lose temp faster, but the heat will still damage the seat. And in order to thermoform, you either need enough mass due to gravity and time, or (like in most cases) vacuum.

 

[TheDeparted]

Is the car seat bottom cloth?

It's leather

What's the end purpose?

Wouldn't you like to know?

Thinner material just means it will get to temp and lose temp faster, but the heat will still damage the seat. And in order to thermoform, you either need enough mass due to gravity and time, or (like in most cases) vacuum.

I don't want to vacuum form onto the seat, I want to make a mold of the seat which will be used for vacuum forming a thicker piece of plastic.

I was thinking that, with a heat gun and a thin plastic that could get to temp and cool easily while I form it by hand, I could make an inverted form of the seat from which I could make a heavier duty mold for proper thermoforming.

 

[Saint_Ward]

It's leather




Wouldn't you like to know?




I don't want to vacuum form onto the seat, I want to make a mold of the seat which will be used for vacuum forming a thicker piece of plastic.

I was thinking that, with a heat gun and a thin plastic that could get to temp and cool easily while I form it by hand, I could make an inverted form of the seat from which I could make a heavier duty mold for proper thermoforming.

I'd test the idea out on something leather you don't care about then first. Try with no powder. Then try with baby powder. Then maybe try with silicone mold release.

Then, make sure whatever you use, you can easily wash off of your seat.

I haven't done much thermal forming myself. We make parts that use that process but someone else does it. I don't know how tacky - if at all - the ABS would get.

Also, depending on the geometry of the shape you're trying to mold, you may not be able to remove the mold (you want a drag angle of 2-4 degrees usually). That's why I was asking the end purpose or what this looks like to get an idea to visualize it.

 

[TheDeparted]

I'd test the idea out on something leather you don't care about then first. Try with no powder. Then try with baby powder. Then maybe try with silicone mold release.

Then, make sure whatever you use, you can easily wash off of your seat.

I haven't done much thermal forming myself. We make parts that use that process but someone else does it. I don't know how tacky - if at all - the ABS would get.

Also, depending on the geometry of the shape you're trying to mold, you may not be able to remove the mold (you want a drag angle of 2-4 degrees usually). That's why I was asking the end purpose or what this looks like to get an idea to visualize it.

Good suggestions. There are no sharp angles, so release won't be a big issue.

 

[staphory]

You could use thin plastic or aluminum foil as protection for the seat and lay fiberglass over that. That would crest your mold. No heat needed.

 

[TheDeparted]

You could use thin plastic or aluminum foil as protection for the seat and lay fiberglass over that. That would crest your mold. No heat needed.

Similar to the momentary thought of papier-mâché I had and summarily dismissed. But better.