Tutorial - How to make a Silicone Mold and Resin/Plastic Castings

**tonyc206** · 12-05-2010 12:10

If you find this boring then blame old Kytey

These photos were all mocked up using using already finished components.

First thing to do is find a flat, non-porous, base (I'm using the glass of a cheap photo frame. Perspex is ideal) and place it on a perfectly level surface (check in both directions).

Place the items (Masters) on the base. I use a non-permanent adhesive to secure them from moving (double-sided tape in this case)

Now comes the Lego bit (KEN!!!)

Build a retaining wall around the masters to contain the liquid silicone. This can be made out of any non-porous material such as modelling clay etc. I always use Lego bricks as they are totally re-useable and it's so easy to make walls of any size.

Then mix up the silicone moulding compound. All of the ones that I have used are mixed 9:1 by weight.

I usually pour the required amount of silicone into a disposable plastic beaker, then place it on a set of digital scales (Yes I use the kitchen scales, but don't tell the Base Commander), poor in the accelerator, mix it until it has a uniform colour, leave to stand for about 10 minutes (or use a vacuum chamber), and then poor over the masters. Be aware that this will seep through the walls slightly, if you are using Lego, so you need to have about a couple of inches of clear space around the sides.

Leave this to cure, at least over night, or preferably for 24 hrs.

Once the silicone has cured remove the Lego bricks. This is another reason why I like them, because they are so easy to break away one at a time. This will leave you with a solid block of silicone like so:

Gently prise this from the base and turn over to reveal the masters.

Don't be surprised if the silicone has seeped under the masters. Just take a very sharp modelling knife and carefully cut as close to the edge as you can. Be careful to aviod going beyond the edge of the masters and damaging the mold.

Now flex the mold and carefully remove the masters to leave the mold ready for casting. A little trimming of any excess silicone may be require or desired here.

When you are ready to start casting, place the mould on a flat and completely level surface.

Then mix the casting compound.

This is a new liquid plastic resin compound that is mixed 1:1 and pours like water. You have 2 minutes working time to mix it and poor into the mold.

After only 10 minutes (much longer for fibreglass resin) the plastic has cured and can be removed from the mold.

Hey presto! You now have some lovely light weight plastic casting that is extremely strong...

...and very flexable. Now all you need to do is clean it up and away you go.

Any questions?

**Guntruck** · 12-05-2010 12:52

Thanks for that Tony. That's certainly fairly flexible. I also like the idea that the plastic is workable in a couple of minutes.

One part mould - interesting. I would have been inclined to to use a two part mould and poured the resin/plastic into the mould, but I guess you can get away with it with wings that have no undersurface detail.

How much shrinkage is there in the plastic compound?

Have you thought of using double sided tape to tack the wing to the baseboard? This might reduce or eliminate the seepage under the wing masters, and reduce work in cleaning the casting later.

Once you have poured the plastic, would placing a piece of glass or plasticard over mould give you a flatter underside (assuming it might squish out excess compund from the mould, but giving a bit of 'flash')? Not tried it myself but I think I will once the materials arrive.

And you shouldn't have shown those bottles again - Kytey's ordered three crates for the mess

**The Cowman** · 12-05-2010 13:02

Thanks Tony! Now I get the who LEGO thing! Will have to give this a try once I get my Gotha kits! (After the holidays... I have stretched my budget for WoW to the limit for now!)

**Jmac** · 12-05-2010 13:32

This looks REALLY cool. Are there any limitations on what types of materials the MAster can be?

Me "Honey, it's really cool, I'm making copies of that item you liked"
Wife "Is your work room on fire?"

Would like to avoid that conversation.

**Skullduggery** · 12-05-2010 14:09

very cool !!. Do you need to apply any release agent or wax to your masters? I would assume not on an easy to mold piece like wings.

**MayorJim** · 12-05-2010 14:38

Thank you for the very nice, step-by-step, explanation...and the pics really made it so much more enjoyable!

**Flying Officer Kyte** · 12-06-2010 00:04

Thanks for that very clear explaination of the process. On the strength of which I will indeed be ordering extra crates of mbfg for the mess.I like to make my orders flexible, rather than set in concrete.

Kyte.

**tonyc206** · 12-06-2010 02:18

Thanks for the nice comments guys. Now to the questions:

Originally Posted by Guntruck

One part mould - interesting. I would have been inclined to to use a two part mould and poured the resin/plastic into the mould, but I guess you can get away with it with wings that have no undersurface detail.

I toyed with a 2-part mold, but decide to do a one-part initially due to the lack of underside detail and the simplicity of a single silicone pour. I'm going to do a 2-part mold next time when I cast my new home-made wing masters, as they will have more detail and will be more accurate. From all the drawings that I've seen the Skytrex lower wing is incorrect (it should be almost the same shape as the upper wing), as is the rake angle on the upper wing and the aileron outlines, strut locations, etc.......

Originally Posted by Guntruck

How much shrinkage is there in the plastic compound?

Nothing noticeable really.

Originally Posted by Guntruck

Have you thought of using double sided tape to tack the wing to the baseboard? This might reduce or eliminate the seepage under the wing masters, and reduce work in cleaning the casting later.

Oh Gunners! I guess you didn't read the bit where I said "I use a non-permanent adhesive to secure them from moving (double-sided tape in this case)"? I think the tape actually caused more seepage. Nextime I think I'd seal the underside to the base with putty or similar.

Originally Posted by Guntruck

Once you have poured the plastic, would placing a piece of glass or plasticard over mould give you a flatter underside (assuming it might squish out excess compund from the mould, but giving a bit of 'flash')? Not tried it myself but I think I will once the materials arrive.

I've not tried it with this new plastic, but with resin it's more problems with the casting sticking to the glass. No I didn't use a release agent either when I tried it

Originally Posted by Guntruck

And you shouldn't have shown those bottles again - Kytey's ordered three crates for the mess

That's not the real problem. It's when I saw him disappear into the gents with the silicone compound I got concerned. BUT I'M NOT GOING IN THERE AFTER HIM!

Originally Posted by Jmac

This looks REALLY cool. Are there any limitations on what types of materials the Master can be?

Not really. The main thing to remember is that it needs to be sealed so that it is completely non-pourous. I've used wood, clay, plastic, Milliputt, green stuff, making sure to seal all joins (and varnish if it's a pourous material) before molding.

Originally Posted by Skullduggery

very cool !!. Do you need to apply any release agent or wax to your masters? I would assume not on an easy to mold piece like wings.

Correct. The plastic and silicone separate very easily.

Originally Posted by Flying Officer Kyte

Thanks for that very clear explaination of the process. On the strength of which I will indeed be ordering extra crates of mbfg for the mess.I like to make my orders flexible, rather than set in concrete.

Kyte.

Right you are sir, but just remember what I said to you before? You need the latex compound for molding body parts

**Lucky Bryan** · 12-06-2010 03:04

Excellent post my friend.

Lucky.

**Guntruck** · 12-06-2010 11:02

Originally Posted by tonyc206

Oh Gunners! I guess you didn't read the bit where I said "I use a non-permanent adhesive to secure them from moving (double-sided tape in this case)"?

'Course I noticed - just testing is all

**Flying Officer Kyte** · 12-06-2010 11:24

Originally Posted by tonyc206

That's not the real problem. It's when I saw him disappear into the gents with the silicone compound I got concerned. BUT I'M NOT GOING IN THERE AFTER HIM!
Right you are sir, but just remember what I said to you before? You need the latex compound for molding body parts

This part of your answer session made me wonder if you have any expertise in producing prosthetic buttocks? After Joanna's brush with the prop blade in the summer she is in dire need of some help from Silly con Man.

Rob.

**The Cowman** · 12-06-2010 11:34

Originally Posted by Guntruck

And you shouldn't have shown those bottles again - Kytey's ordered three crates for the mess

Originally Posted by tonyc206

That's not the real problem. It's when I saw him disappear into the gents with the silicone compound I got concerned. BUT I'M NOT GOING IN THERE AFTER HIM!

Originally Posted by Flying Officer Kyte

This part of your answer session made me wonder if you have any expertise in producing prosthetic buttocks? After Joanna's brush with the prop blade in the summer she is in dire need of some helf from Silly con Man.

Rob.

LOL Ya know... you guys are a bit odd... almost in a sick sort of way...

Definitely my kind of people!

**Attila57** · 12-06-2010 13:04

A good tutorial, Tony!

Attilio

**tonyc206** · 12-06-2010 14:15

Originally Posted by Flying Officer Kyte

This part of your answer session made me wonder if you have any expertise in producing prosthetic buttocks? After Joanna's brush with the prop blade in the summer she is in dire need of some help from Silly con Man.

Rob.

No buttocks, but I have been known to make the occaisional boob!

**Guntruck** · 12-07-2010 01:18

I've occasionally made an a**e of myself......

**flash** · 12-07-2010 01:42

Nice one Tony - not boring - inspirational !

I share your concern re certain persons & body parts

**Flying Officer Kyte** · 12-07-2010 03:44

Originally Posted by Guntruck

I've occasionally made an a**e of myself......

Can you tell me Gunners, do you work from a photocopy or a blueprint?

Rob.

**The Cowman** · 12-07-2010 05:55

Originally Posted by Flying Officer Kyte

Can you tell me Gunners, do you work from a photocopy or a blueprint?

Rob.

I would think he gets his instructions like most of us do... from a "how to" guide on an some internet forum!

**Flying Officer Kyte** · 12-07-2010 06:40

Originally Posted by The Cowman

I would think he gets his instructions like most of us do... from a "how to" guide on an some internet forum!

I had heard that forums like that existed Ken, but I have a blocker on to stop me accessing that sort of unsavoury site.

Rob.

**Khargor** · 12-07-2010 09:22

Brilliant tutorial! Thanks for taking the time to make it so straightforward and easy to understand

**phililphall** · 12-07-2010 09:37

And it is illegal if you use a master you didn't make yourself. Copyright laws, you know. Let's ask the Colonel how he feels about folks making copies of his smoke and flame markers?

**Guntruck** · 12-07-2010 10:15

Originally Posted by Flying Officer Kyte

Can you tell me Gunners, do you work from a photocopy or a blueprint?

Rob.

Been using a photo of you for reference

**Flying Officer Kyte** · 12-07-2010 10:53

Originally Posted by Guntruck

Been using a photo of you for reference

Very flattering indeed Gunners. Making a posterior of yourself using me as a model. Must be because I'm so po faced.

No I will not prosecute you for making a copy of my master as long as you don't offer them up for sale, After all I'm pretty safe there. Who would want to buy your ar*e with my face on it.
Rob.

**MayorJim** · 12-07-2010 12:58

Originally Posted by phililphall

And it is illegal if you use a master you didn't make yourself. Copyright laws, you know. Let's ask the Colonel how he feels about folks making copies of his smoke and flame markers?

Excellent point...unless for personal use or body parts?

**phililphall** · 12-07-2010 13:17

Nope. Not even for personal use unless it is a written item and you only use it to quote the article/book in a small way. You can't quote a complete book or article. Things like models are completely protected. You need the author/sculptors permission to make a recast of his work.

**The Cowman** · 12-07-2010 16:37

Originally Posted by phililphall

Nope. Not even for personal use unless it is a written item and you only use it to quote the article/book in a small way. You can't quote a complete book or article. Things like models are completely protected. You need the author/sculptors permission to make a recast of his work.

Ruh Roh Tony... you had better pack up and head for Australia!!!

**Guntruck** · 12-08-2010 01:04

Save yourself Tony - hide the moulds! I know, send them to me and I will hide them for you...

**tonyc206** · 12-08-2010 01:15

Originally Posted by phililphall

And it is illegal if you use a master you didn't make yourself. Copyright laws, you know. Let's ask the Colonel how he feels about folks making copies of his smoke and flame markers?

You are absolutely correct, although the laws do differ from country to country. However having had many converstaions with 'Mr Skytrex' and many others in the British wargame model manufacturers commuinty for many uears now (I used to be part of that community and 'Ground Zero Games' still carry some of my models that I made the original sculpts for) I can assure you that I there is no issue with me using these parts for a tutorial demonstration or indeed to replace the originals on my own models.

The main point as far as the manufactures are concerned (and not the anally retentive members of the legal community) is that any act of replication by an individual does not negatively affect the sales of their products or their profits in any way. Replicating these wings does not affect the sales of Skytrex products as I need to buy the model in order to replace it's wings with plastic ones. As would anyone else who did the same thing.

Making copies of the Colonels flames markers would be replicating a complete model. Reducing the need to purchase originals and thereby reduce the number of sales that he would otherwise have.

As stated above I will not be selling, or using, these wings that I have replicated and will be creating my own masters some time soon from which I will re-cast replacement wings for all of my Skytrex Gothas and those I will be able to sell (should I wish to). Even then it will not affect Skytrex in a negative way as I wiil only be suppling a replacement part that will still require the purchasing of an original model from Skytrex.

**The Cowman** · 12-08-2010 01:33

Originally Posted by tonyc206

You are absolutely correct, although the laws do differ from country to country. However having had many converstaions with 'Mr Skytrex' and many others in the British wargame model manufacturers commuinty for many uears now (I used to be part of that community and 'Ground Zero Games' still carry some of my models that I made the original sculpts for) I can assure you that I there is no issue with me using these parts for a tutorial demonstration or indeed to replace the originals on my own models.

The main point as far as the manufactures are concerned (and not the anally retentive members of the legal community) is that any act of replication by an individual does not negatively affect the sales of their products or their profits in any way. Replicating these wings does not affect the sales of Skytrex products as I need to buy the model in order to replace it's wings with plastic ones. As would anyone else who did the same thing.

Making copies of the Colonels flames markers would be replicating a complete model. Reducing the need to purchase originals and thereby reduce the number of sales that he would otherwise have.

As stated above I will not be selling, or using, these wings that I have replicated and will be creating my own masters some time soon from which I will re-cast replacement wings for all of my Skytrex Gothas and those I will be able to sell (should I wish to). Even then it will not affect Skytrex in a negative way as I wiil only be suppling a replacement part that will still require the purchasing of an original model from Skytrex.

Aww Pickles!! Here I thought maybe I could come hang with you in the Outback and learn some of your secret painting techniques... and find out what Roo steak tastes like...guess I will have to just keep watching for your tutorials for now!

**tonyc206** · 12-08-2010 03:50

Originally Posted by The Cowman

Aww Pickles!! Here I thought maybe I could come hang with you in the Outback and learn some of your secret painting techniques... and find out what Roo steak tastes like...guess I will have to just keep watching for your tutorials for now!

I think the room next door to mine in this nice hosptal is free. The walls are lovely and soft, and they give us lots of crayons (salavates...)

**phililphall** · 12-08-2010 07:38

Tony you are fortunate in having permission. I find that very few companies are willing to let you recast for your own use since they tend to be small businesses with a low cash flow and would rather sell you their product instead of letting you cast your own.

In the U.S. it is simply illegal without permission. It doesn't matter whether you intend to sell it or use it yourself.

**tuladin** · 12-08-2010 08:43

What is the penalty for making such copies? And how would they enforce the law? If caught, would you be arrested or just sued.

It doesn't matter too much to me - if it is illegal, I won't do it. I don't want to end up posting a thread entitled "Tutorial - How to Make a License Plate"!

**Von Rotherham** · 12-08-2010 10:25

Brilliant post! Thanks for the info, I've been wondering how to make moulds myself for some time. I'm interested in seeing how you go about making a double mould though!

**crashx** · 12-08-2010 10:50

This is great Tony. Thanks, this is explaned well. And thanks for the new idea with the Legos, now I have a way to deal with the landmines left on the floor by my son when I'm walking around the house barefoot.

**phililphall** · 12-08-2010 11:18

You pay damages based on how much the owner of the copyright could have expected from the sale of the number of pieces produced. You pay all legal fees of both sides. You can go to jail. Unless you have really produced a lot of items the biggest cost will be paying for both of the lawyers. Jail time is usually given if you ignored cease and desist notices from the owners attorneys.

**tonyc206** · 12-08-2010 13:38

Originally Posted by Von Rotherham

Brilliant post! Thanks for the info, I've been wondering how to make moulds myself for some time. I'm interested in seeing how you go about making a double mould though!

My pleasure. I'll probably do the 2-part mold sometime after Xmas.

Originally Posted by crashx

This is great Tony. Thanks, this is explaned well. And thanks for the new idea with the Legos, now I have a way to deal with the landmines left on the floor by my son when I'm walking around the house barefoot.

Yep, I got mine by stealing it off my grandsons

Not really. I just said "Grandad needs some pieces of lego" and 2 minutes later the youngest came in with a bag full. Aw bless!

**MayorJim** · 12-08-2010 14:25

Originally Posted by tuladin

What is the penalty for making such copies? And how would they enforce the law? If caught, would you be arrested or just sued.

It doesn't matter too much to me - if it is illegal, I won't do it. I don't want to end up posting a thread entitled "Tutorial - How to Make a License Plate"!

LOL! I remember when I was in college...had an "artsy' friend who made a great copy of the state license plate...out of cardboard. First heavy rain and the cops got us for fake plates! Fortunately, my buddy only got fined for not having legal plates vs fines for forgery or whatever...they did look good though!

**Stormkahn** · 02-21-2011 13:51

How'd you get on with the 2 part mold Tony, I'm curious how you create the 2 halves effectively?

cheer,

Dave.

**tonyc206** · 02-22-2011 12:46

Originally Posted by Stormkahn

How'd you get on with the 2 part mold Tony, I'm curious how you create the 2 halves effectively?

cheer,

Dave.

Haven't done it yet dave. I'll post it when I do.

Don't have much time or energy at the moment as we got a new puppy and he takes some looking after, but he's well worth it