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Resin Casting Wheels


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I only make two part molds. Small parts like wheels and dash parts, etc, I mix up a small amount of silicone and pour it in the detail and run it through my vacuum chamber a few times. If I just put in a little and let it set it just about always gets a tiny air bubble in it and in this scale it looks bad. You could put just a drop of silicone in to start out with. Take a tooth pick and baby set it until you are certain no air bubbles still exist. Let the silicone cure completely and then build up another layer until you get what you want from it. If you don't do this or have the equipment to vacuum it a tiny bubble will form next to some detail. When you make the resin part a tiny bump of resin will appear on your part. Most of the time they will remove very easily because it is round it should knock right off

I have also experimented in the beginning to correct molds that have had air bubbles in them. It is a tedious task. I have used super glue, silicone grease and of course the silicone I use to make the mold. Resin casting is a huge learning experience. It takes a good bit of equipment and space to do it in. I have built a good bit of shelving to store molds on too. I would like to see how Modelhaus stores and keeps track of his molds. That in itself is a big task.

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Wheels are easy. Steve, the simplest way would be to file the back of the wheel flat (so remove the lip on the back of the wheel). You'll also want to do this to the wheel back (inner wheel) which you also posted pics of. Then, simply make a one piece mold of these. If you want to avoid bubbles or any imperfections on your cast piece simply take a small paint brush and brush on a layer of silicone mold making rubber on to your master to ensure there are no trapped air bubbles. Afterwards simply drizzle in your silicone rubber into your mold and let it cure. I've done this countless times with flawless results. If you want the back of your wheel (and wheel backs) to be flat and clean when cast simply pour in your casting resin into the mold and place a piece of 1/4 inch glass on top of the mold (carefully). You can watch the resin cure through the glass and when fully cured carefully pull the MOLD from the glass. Your cast wheels (or whatever) will now be stuck to the glass. Simply use a flat razor blade and work the finished resin edges free from the glass. You now have perfectly clean cast wheels with perfectly flat and clean backsides. This technique works best if you mist your piece of glass with mold release prior to setting on top of your mold. Every couple pours its best to spray a lil more mold release on the glass to make it easy to remove your resin pieces. Thats how I would do it. It would give you the best results and its the easiest. A two piece mold would be extra work and the only point of that is to have the detail present that is on the BACKSIDE of the wheel. However, there is normally no point to this because you cant see the back side of a wheel once its placed in a tire. Of course there are lots of other tips and tricks but if your already experimenting with resin casting than I take it you know the basics. You do not need a vacuum chamber whatsoever for simple things like this.

These wheels were done exactly as I described above-

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Edited by shucky
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how would you do tires with white wall inserts?

A bit more complicated. MOdelhaus does this kind of whitewall tire--black resin tire, with white resin whitewall insert pressed into it. To master this will take a small lathe, and some practice to get masters that fit cleanly together.

Art

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I'm sorry, but I don't see what a lathe has anything to do with casting a tire with a whitewall insert. I'm a very amateur caster that makes parts for my own use, and I didn't need a lathe to cast tires with whitewall inserts, just some casting rubber and resin. And here I thought I didn't have the knowledge of casting to make a 1/350 scale ant, but the way it sounds now I'm a master!! :huh::blink::unsure:

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I'm guessing Art is referring to black wall tires that do not already have slots cut in them to accept the white wall "insert." In order to make tires such as these into usable masters you would need to machine the fine slot required into the side of the tire in order to accept a white wall insert.

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I'm guessing Art is referring to black wall tires that do not already have slots cut in them to accept the white wall "insert." In order to make tires such as these into usable masters you would need to machine the fine slot required into the side of the tire in order to accept a white wall insert.

That's the only way I can see doing a tire that takes a separate whitewall insert. Barring that or making your own master from scratch, I don't think a lathe would be necessary, though.

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Chuck that depends on what you want to do with it. If your making these for yourself you could get by with simple hand tools. If your making a master for a production run my best guess would be you'd want the master to be as perfect as possible. For that, I would say a lathe would be my choice. This would ensure the tire is completely round and the slot cut for the white wall insert is centered and the tolerance is tight. Just my 2 cents as I've tried this myself.

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