Step by step How-To make bodies with resin

Just updated on muy website.

In this tutorial I will explain how to realize the molds that will be needed to be able to realize our pieces in resin. There are several ways or methods to do them but I will show to you one which is perfect if you don't have the vacuum pump etc. This tutorial basically will work for the thin pieces and for the motorcycle or cars body.

Materials

*Silicone/catalyst : The basic material for the creation of the mold

*Mold release : Indispensable material, without it, the pieces might remain caught inside the mold in the moment to throw the second part of the silicone, definitively to be able to separate both parts of silicone..

*Plasticine: For the mold preparation.

*Scales: to be able to calculate the proportion silicone - catalyst.

*Container or glass: to do the mixtures of silicone - catalyst.

*Sticks: to be able to do the mixture.

*Gloves: The silicone is a very dirty material, to the effect that it is very viscous and difficultly the water and the soap, could help us.



The first step, will consist of refilling the piece that we are going to copy, of plasticine, like shown in this image, you can see the clear lilac colour part is because is filled with plasticine too. In this step is advisable to wash or spray the plasticine with mold release because will be more easy to separate the plasticine of the silicone once dry.

The image shows the body of the motorcycle in the side view that is not solid, it has a thickness.

http://www.rocascalemotorcycles.com/tutoriales/carrocerias/howtocopy1.png

Once we have it ready we will start to create a box with carton or pieces from lego etc. we should make sure that this is ok and well locked so one good thing is to put the plasticine in the corners of the box.

Later we will go to calculate the weight of the silicone and make the mixture with the catalyst ( read the instrucions of the manufacter to see the % of catalyst for the silicone )
A good tip to throw the silicone, is throw it from height to allow it to eliminate the bubbles while the jet is thin

In the following image you can see how the silicone is filling the mold.

http://www.rocascalemotorcycles.com/tutoriales/carrocerias/howtocopy2.png

We will have our first mold done. The next image that shows two squares is from the down view. The next step will consist to remove all the plasticine from inside the mold/piece but attention!! do not retire the piece because it will delimit the thickness of the piece once with resin

Here is the picture that shows the mold from the side view with the piece in and without the plasticine.


http://www.rocascalemotorcycles.com/tutoriales/carrocerias/howtocopy4.png


The next step will consist in fill the mold with the piece inside but ATTENTION!!!! we have to put in the interior of the mold the separator material to separate the two pieces of silicone!! only separator in the silicone part not in the interior of the piece

http://www.rocascalemotorcycles.com/tutoriales/carrocerias/howtocopy3.png

Here is the explanation of these steps with photos:

In this photo the positive mold (right) will be the first step when the plasticine holds the piece.

http://www.rocascalemotorcycles.com/tutoriales/carrocerias/howtocopy5.jpg

Here you can see the positive mold is the interior part of the piece and the negative (the one with the hole) is the exterior part.

http://www.rocascalemotorcycles.com/tutoriales/carrocerias/howtocopy6.jpg

Here is the exterior part of the body in the negative mold.

http://www.rocascalemotorcycles.com/tutoriales/carrocerias/howtocopy7.jpg



Second Part

Creating the piece in resin.



Here is the explanation of the second part of this How-To to create our motorcycle or car bodies in resin.

Materials

*Resin - catalyst

*Gloves

*Glasses of plastic

*Sticks to remove the mixture

We start with the mixture of the two parts (catalyst and resin) with the same quantity for both we have to do it hurriedly because the resin dry fast so once the mixture is completed we have to throw it inside the negative mold but REMEMBER!! do not fill all the mold with resin because once we put the positive mold the remaining resin will go out.

http://www.rocascalemotorcycles.com/tutoriales/carrocerias/howtocopy8.jpg

We move and incline the mold in such a way that the resin wets the whole interior part of the mold.

http://www.rocascalemotorcycles.com/tutoriales/carrocerias/howtocopy9.jpg

Now with a lot of care we introduce the positive mold in the hole, slow in order to allow the air goes out, finally once the mold is fitted, we will see as the remaining resin has gone out, this is a good sign , otherwise we would not have the piece complete. (This is the same effect if you fill a glass with water and you put the hand inside, the water will rise the level)

http://www.rocascalemotorcycles.com/tutoriales/carrocerias/howtocopy10.jpg

We withdraw the remaining resin, once dry, and proceed to withdraw the positive mold carefully.


http://www.rocascalemotorcycles.com/tutoriales/carrocerias/howtocopy11.jpg
http://www.rocascalemotorcycles.com/tutoriales/carrocerias/howtocopy12.jpg

And here we have the piece, now we should remove the surplus with a knife or with the fingers, for the posterior work of painting, decals , etc.

http://www.rocascalemotorcycles.com/tutoriales/carrocerias/howtocopy13.jpg

I recommend to leave the piece in the positive mold until it dries

http://www.rocascalemotorcycles.com/tutoriales/carrocerias/howtocopy14.jpg



I hope you like it and how I said in the first part there are many ways to make it and this is mine.

Remember to use gloves and mask, also work with suitable clothes.

Where to find this products??

In Spain: www.feroca.com

In USA: www.alumilite.com



If you have questions, reply here.
Bye!
Roca.

Brilliant, thanks for sharing

WOW super cool stuff! I need to take my time to read it carefully! Thanks a lot for sharing!

great write up. I hadn't thought of using a displacement type mold like that. do you have any problems with air bubbles (pin holes and gaps in the finished parts)?

I'll have to try this methon on some wheels I'm working on.

How do you line up the positive mold with the outer mold? Also, how do you keep the positive from pushing all the way down to the bottom?

Thank's
great write up. I hadn't thought of using a displacement type mold like that. do you have any problems with air bubbles (pin holes and gaps in the finished parts)?

I'll have to try this methon on some wheels I'm working on.

The bubbles are not the main problem, sometimes the problem is on the cylinder small parts they are not filled completely but maybe if I try to move the mold once the resin is inside I can solve the problem, the other option is fill the negative cylinder and then put it in the positive.

How do you line up the positive mold with the outer mold? Also, how do you keep the positive from pushing all the way down to the bottom?

The 2 molds fit perfectly in other words is impossible to put the positive mold in other way to the negative mold, the hole is the same shape as the positive mold.For the positive mold I only have to push a little and then for remove it I open the hole with the fingers for the sides and take the positive mold and I remove it from the negative carefully.

I hope I resolved your questions.
Roca.

When you first started with the "master", what did you fill it with, before placing it in the box and pouring the silicon RTV around it?

I re-read your wording, and I think the answer to my question is Plasticine. Where can you purchase this?

Also, what brand of mold release are you using?

How do you line up the positive mold with the outer mold? Also, how do you keep the positive from pushing all the way down to the bottom?

The method I use is to box the female mold (outer) with the box extending about .5 inches above the mold and pour the male (inner) mold to the top of the box. When cured the inner mold piece will have a lip on it like the cap of a container. on some molds it is advisable to carefully cut vent channels in the inner mold from the part to the surface.

This is a good writeup, but one important thing that was left out is that some brands of RTV will react with the clay you use to form the inner mold. You should use clay (referred to here as plasticine) with no sulfur content. In the USA a good brand to use is "Kleen Clay" It is available at most art supply stores.

the alumilite set comes with a sulfer free clay, as does the set from micro mark.

I'm guessing that plasticine is another word for modelling clay?

I'd like to find a clay that will make a form, harden to an rtv consistency so it would come out of the master part cleanly.