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It's a different product, the easycast I use is white not clear. I do have a clear resin from the same suppliers but it cured all right, after 2 days!

I'm pretty sure I have used Smooth Cast a few years back and I had a lot of success with it so if you are in the states it is definitely a good option.

Thanks alot for the tips!!!

Got a new batch of Oomoo in today, but none of my projects can be posted here. Someone send me something original to do a 2 part mold tutorial on.

LOL, if I wasn't so far away I would definitely do it!

Today I'm doing the second part of my custom base mold, which is taking a set of pulls from my original mold of 3 and using them with the masters to make a mold of 6 bases.

This is beneficial in 2 ways:
1st you can now cast up to 9 at a time instead of just 3.
2nd you can save your master mold to make future pulls to make subsequent molds from. The more you cast resin, the more compounds are leeched from the silicone and eventually the mold needs to be replaced.

I also recommend using a higher quality silicone for master molds such as the one I did last week using GE RTV662a which is a 10:1 rubber. It has a VERY high strength and thus doesn't flex nearly as much as Oomoo 25.

I'll get pics up in a few hours, just waiting for this mold to cure.


Automatically Appended Next Post:
So today I made my expanded mold for my ruined flagstone bases. I used Oomoo 25 which
is a 1:1 RTV silicone.


As always I glued my masters down onto glass.


I then made my form around it with Legos. Sidenote: this mold is the same size as the
original mold, but has twice as many bases on it.



I used Alumilite Rubber to Rubber mold release, which technically isn't for this application,
but I find it works just as well. Mold release is more or less low viscosity grease and will
make your masters look wet.


After my form was ready and glued in place, I mixed up my silicone by eyeballing it.


For best results, mix by pouring one into the others cup. Mix as well as you can, then pour
the silicone out into the other cup. This is to help the unmixed parts on the side of the cups
get mixed in and helps with the overall strength of your mold.

Once you are ready to pour, pound the cup on your desk for a few minutes to force out as
many bubbles as possible. Oomoo 25 has a 15 minute pot life, which is plenty long enough to
get bubbles out before it cures in the cup.

Now we are ready to pour. I hold the cup about 10-12 inches above the form and only let a
very thin stream of silicone touch down in a corner of the form. We want the silicone to
cover itself over the masters, and to prevent bubbles we never pour directly onto the pieces.


The reason we use a thin stream is to continue breaking apart bubbles as they fall. The silicone
stretches and the bubbles are forced to pop.

The silicone will naturally settle itself level as long as it's on a level surface. Oomoo 25 has a 75
minute demold time, so to err on the side of caution I gave mine 3 hours to cure before using
it.

Once everything is cured, pull the mold off the glass, pull out the masters, and mix up some
resin. With resin you don't need to go from one cup to the other as it is generally thin enough
to not need such rigorous mixing. My Smooth Cast 300 only has a 2 minute pot life, so I have
to work fast, and any mistakes are likely going to be a miscast.

Here's both molds from this past week together.


And a finished tile.

This was a learning experience as I forgot to wash it off before priming.
If you don't wash the parts in soapy water then paint will slide right off after a little bit of
handling.


Now that I can make enough at one time, I'll be offering these bases in sets of 5. I am still
sculpting the 25x50mm bases. If I get a big enough order I'll do other sizes as well. $.50 per
base is what I'm thinking at the moment. Perhaps a wee discount with larger orders.

Fantastic Aerethan! Thanks for another great tutorial, OOMOO looks like a great product, 3 hours is a decent demold time for a silicone.

Hope you get some orders for your bases!

Wow, that's really cool aerethan, thanks for taking the time... and really neat tiles!

As soon as I find something worthy of my time that I'm allowed to post(meaning not illegal) I'll put a 2 part mold tutorial up.

This is a great little bit. A long time ago i cast up some of my own bases, craters and armour bits for tanks using Silicon from a little (now closed hobbyshop) and Car body work repair resin id bought from Halfords.

That resin got very hot and in the end damaged the moulds. Does the stuff you recommend get hot as it sets ?

You reckon you can get the stuff to do this from Hobbycraft ? as a new one has opened up in Aberdeen.

Also for bigger terrain pieces could a bigger version of these moulds work with say Plaster? or maybe even modelling Clay ?

Clay wouldn't likely work. Plaster would work quite well. I refer you to www.hirstarts.com for plaster technique. His molds are far superior to anything I'm making as well.

All resin will cause some heat when mixed and curing. Large pieces of resin will have much higher temperatures. Slower cure times may help with this although I am not 100% sure.

For larger pieces I'd recommend using plaster despite the weight issue.

For bigger pieces I would probably pour in sections with resin as it adheres to itself well from what I gather. Depending on the size and application of the piece though I don't see why you couldn't use plaster or clay, though I'm not sure what the times for it curing/going off would be.

Clay is too thick to be very useful at casting, and it would be too brittle in such small items. Gypsum Plaster is what you want.

@DaHedd: Speaking on behalf of BLACKHAND and myself, as we both use the same products, the heat issues are negligible.

As you could find we use Pinkysil for moulds and Easycast for the actual pours.

I have noticed with some deeper pours like the bases there can be a bit of heat generated, although it does not warp the pinysil as it either does not expand enough or expands at a contained rate with heat.

In any case the heat is not enough to cause problems with pours of less than 5mm thick. Haven't tried any thicker.


Klaw

I personally pour the resin themn sit a heat lamp about 5cm away and heat up the resin, it make sit cure faster!

I have yet to notice any degradation in the pinkasyil moulds but over time I gues I will find out.

Nothing like a 5 minute demould time for a resin addict

Thanks. This has been very insightful.

How I love the speed of pinkysil and easycast. I'd rather greenstuff a piece, mould it, cast it, then see if it's any good rather than wait for greenstuff to cure.

Lol, patience Klaw! I know what you mean though, I have sped through many a casting in a night.

I am currently working on yet another shoulderpad and chest piece combo for my Sabre Legion Terminators so I will try and remember to take pics and post em up....

...and as soon as a little project arrives at a friend's house and he posts pics of the finished product up here on his painting blog I will be able to post pics of the casting process for that.

Wow I'm not sure if that last bit made a lot of sense but you'll get the idea.

Looking forward to it. With....patience.

Just poured my first mold. I however completely forgot to spray it with release agent, so not sure how its going to come out.

Depending on the product you should be fine, next time spray or use talcum powder!

It came off the plastic bits fine, but stuck to the Plexiglas I used as the foundation.

Question for you casting vets. How do I prevent the bubble inside the shoulder pads? I couldn't get a tooth pick in there. I don't think it will ruin anything, as I can just cut the resin out when cast.

talcum powder or degassing.

Edit: nothing new to add

Does talcum powder work with pinkysil?

@Captain Klaw - yep talcum works, usually don't need it though

@whalemusic - Can you post some pics of your mould so we can get an idea of your setup?

Sorry, should have specified: does it help in reducing bubbles? With pinkysil moulds it isn't such a problem as you can manipulate them when you pour the resin to get some bubbles out, but still there is a high rate of miscasts in shoulderpads due to bubbles...

If you are miscasting it may be due to how fast you are filling the mold and if you are flexing it while you pour.

Also the type of resin you are using can make a difference. Smooth Cast 300 is self degassing, so as it sets the bubbles make their way to the top. The only trouble I have is with very fine detail molds which I'm hoping to remedy with my longer cure time resin.

Sorry guys I don't have too much of a problem any more, I just poke (pretty viciously) into the areas I know will be a problem, the edges of the mould and such, and I get most of the bubbles.

Without seeing how you have set up the mould I can't really give you a good idea how to fix the issue.

My mould is the same as yours, I think I posted pics earlier. I'm thinking I need some eye-droppers so I can make smaller batches and focus on each pour more without worrying about the resin drying before I can use it.

I use 10cc syringes for my 2 part molds. You may want to try those out.