Hi Folk just a quick Question on Resin Casting.

What is the easiest, simplest and Quickest way to build mould boxes?

I do not simply mean an old tin or container, or for that matter plastic building blocks (which leak like a hole in a Dyke) but something more like a wooden, adjustable frame or something similar that can be used a multiple of times.

As I have broken my modelers block for the moment and the mate that does my casting is very busy I thought I would do my own again but would like to set it up right from the word go to make it easier on myself.

Thanks
Cliff

PS> Tread you are good at designing things

Cliff,

The way I make my casting molds is by taking four pieces of thick styrene strips (about 2 - 3 mm thick and 5cm wide). I then make a "frame" or a "box"out of them and tape all pieces together so that they don't fall apart. Then, I use non-hardening modeling clay and apply it all the way around the frame pressing it firmly to the base. This seals all the edges at the base of my box and also prevents the "frame" from moving. When I am done making my mold, I simple collect the clay, styrene and remove the tape and set it aside for next time. I hope this makes sense to you.

I have seen some that were made of metal plates and were hot glued together. This is a neat way to have some reusable molds that can be made in different sizes. I have used these types and find them great. I make mine out of thin aluminum The hot glue holds them without leaking and they come apart easy and the glue will peal off easy.

thanks guys I never tought of the hot glue method

I use legos for my mold boxes with no leaks.. They work great and you can build some pretty complex molds with them. The trick is to use hot glue to attach the "walls" to the base and seal the corners. I do use other things if I need a quick box, such as scrap styrene or acrylic.

Why o why do we try to make such complicated structures. The shape of what we mold in is not important, it's the model itself...

So if I need a quick container to pour the silicone, I make one out of plasticine (or play-doh as it is known in the US of A).

Quick, your model sticks to it so no elaborate fixings and once your silicone mold is solidified you just peel it off...

If you want I can post some pictures of a demo I did on a modelling show where we were present with an Armorama stand.

Kris

Yep, I have made quite a few out of plasticine clay also. This works especially well for molding, say, a part on a weapon when you can't remove the part itself, i.e., sights and such.

I make the molds so that I can use them over again. to make a lot of the parts. I find that if I box shape the part with thick sides I will not get any distortions in the new part or in the mold itself. I sometimes make 50 to 100 parts of a single item and I need the mold to be very sturdy.

I would love to see some photos of your method. I am always looking for new ways to do things.

Hey guys-
Where is the best place to learn about resin casting? I would love to be able to give it a try. Any info would be greatly appeciated. Thank you

I've used Lego's and I have some small craft plastic storage boxes.. about 6 inchs by 4 inchs that are divided up into compartments... (have several different ones with differnt size and number of compartments)

I use white glue to glue the parts into the bottom of the box and pour my mold materrial in that. (sprayed with mold release of course) and it works great.

makes a nice mold with smooth even sides and corners..

course they only work with stuff that has one flat side..

I havn't done anything that requires a double sided mold yet..

I learned about resin casting by reading a lot of stuff here on the net and I've done a little of it using Micro-Marks resin kit starter set the sell for about $70 u get everything you need to make molds and resin parts. in a easy to use kit.

There are some features here on pouring resin.

https://armorama.kitmaker.net//features/150

https://armorama.kitmaker.net//features/373


You could use the technique in this for resin too.
https://armorama.kitmaker.net//features/248

To address the 1st question asked - I would use any of the previously mentioned methods, legos, styrene, wood etc Then line the basic mold with kitchen foil.

One way to build a mold frame is out of plexiglass 1/4" (6mm) or better. Then I hold it together with putting the seams. I haven't used this method with resin yet but I do use it on wax and plaster mold and it has worked well.
You can get scrap plexiglass from glass shops and big box stores (i.e. Home Depot, Lowe's) for little or better no money.
If it is a very large mold you can use cut pieces of old counter tops or if you know someone that installs counters you can get the sink cut out and cut you "walls and floor" from it.

Hope this helps.

Dave

Oops, misinterpretation here... I don't use the plasticine as mold material, I just use it to make the container. The molding material is silicone (well special type). This stuff allows you to make a couple of hunderd copies without problems.




As I already told Dave (Grumpy) I'm currently preparing an article on the subject (in different episodes due to the nature of the subject).
Because I have noticed, a) there is a lot of interest, b) some people have tried, but were dissapointed in the end result due to the fact that minor attention points were missed, c) people think it is rocket science or magic, when in fact it is very simple if you take in account those all important details.

So I hope to publish the first episode on friday.

Kris

Quickest and easiest way I have found is with the Lego's building blocks. Yes they will leak, but this can be prevented by applying a thin layyer of rubber cement to the inside of the blocks. It dries quickly and solves the problem at hand. I place my boxes on a rolled out piece of clay and press it into the clay for a nice tight seal. I make the boxes quite a lot taller to allow for expansion as I place the mold in a vaccum chamber to evacuate the air and obtain better molds. The rubber swells due to the air leaving and the taller boxes provide for this expansion. Once de-aired, I let it cure out at least 24 hours before even thinking of demolding the master. When I cast I will pour the resin into the molds and place the mold in a pressure chamber and hit it with 40-50 psi of air pressure. This ensures that the resin gets into all the little nooks and crannys and the I have nice crisp parts each and every time. "Q"