Any experience duplicating chess sets in resin?

I'm thinking of taking up the hobby of resin casting in order to duplicate (or, in some cases, make some replacement pieces for) some vintage plastic chess sets that I own.  This would involve creating silicone molds of the pieces and casting the pieces in resin, possibly mixed with other materials to achieve a metal, wood, or stone appearance. 

Does anyone here have any experience or advice they'd be willing to share? 

Best advice I could give would be to watch Robert Tolone on YouTube in order to get solid knowledge of the craft of duplicating Chess pieces in Urethane resin using Silicone rubber molds from project start to finish, and see if it's really a process you wish to involve yourself in. https://www.youtube.com/watch?v=81TqBw7dn8k 

Additionally, I would watch Robert's video on 'Top Ten Tools For A Resin Casting Studio'; to understand what tools and equipment you will need. https://www.youtube.com/watch?v=qDLgTtQybiQ&t=7s

Lastly, I would watch Robert's resin casting project on the fish sculpture, as this piece has features which will represent casting and issues you will face doing certain Chessmen. Although Robert uses a different molding technique on this one - which you will not need to use to do Chessmen, which only require a plastic tumbler as the so-called 'mold box' -  the fish sculpture has spiny fins which are much like the spikes on the Queen's crown; and, the opening for the mouth of the fish on this sculpt is somewhat similar to what you will be dealing with in trying to get a clean and proper casting on the cut which creates the mitre on the Bishop's hat. https://www.youtube.com/watch?v=8gmajR913Qc

Of course, the piece which will prove most difficult in creating bubble-free castings is the same piece which causes the most issues for wood carvers; and that is, the Knight - the more highly-figured and detailed the more care is required; and, the higher the probability of unsatisfactory results.

Look for other videos by Robert Tolone on his channel where he addresses proper venting of undercut sections and those pieces with fine surface detail - again, in preparation of what will be required to successfully cast intricate Knights.

You'll be in good hands under the teachings of Robert Tolone.

Best of luck to you if you decide to give it go!

Feel free to PM me, if I can help you further.

Thank you @Boydcarts and @CampwoodsRD.  I've been going down the rabbit hole with both Smooth-On and Robert Tolone's YouTube channels for the past week and their videos are my main inspiration. 

@CamwoodsRD, you hit the nail on the head with some of the specific questions I have, like where are the problem areas for chess pieces where I will need to put vents.  My initial plan is to cast a few replacement pawns for a Gamine-like set (an early 60s copycat that I found at a thrift store).  Luckily there aren't any holes, divots, or sharp corners on those pieces, so it will hopefully be a good test project.

One question that I have is how many resin castings I get from a single silicone mold.  But some quick searching on google tells me that it depends on a lot of factors.  I guess I should just try and see (and then pester you with PMs ). 

No worries, PM whenever you wish.

So glad to hear you are studying with Robert - He is THE MAN! The Crafsman, who is less geared toward 'Pro Casting Shop Production' and more geared to 'Dollar Store Home Production' is also very, very good. https://www.youtube.com/@TheCrafsMan/videos

However, no one beats Robert at identifying potential problem areas on a part to be cast and selecting venting strategies.

To answer your question: How many pulls a mold can birth depends on many factors. The rounder and smoother a casting is, the longer the mold will last; and, the sharper and rougher with more highly detailed and/or tight crevices a casting has, the more each pull creates wear on the interior of the mold surface. Eventually, you mold will reach a point where the casting are missing details, etc.

Also, how long you leave the casting in mold before demolding will affect it's long-term life, the more aggressive and the hotter the exothermic throw the resin formulation you have chosen matters too; as well as, if you use a mold release agent or not. Robert does not normally subscribe to using a mold release unless he is dealing with a mold that has extreme tight areas; whereas, I used to always use a mold release agent for long-term mold health and increased longevity.

Would you post a picture of the pieces you plan on casting, please. I would like to see them.

Thanks.

I picked this set up from a local thrift store for $3, but it is unfortunately missing 3 black pawns.  It's a small hollow plastic set put out by Western Publishing in 1963 and is a copycat of the Gamine set (except that they kept the Staunton knight and rook for some reason).  The kings are 2 5/8"; the pawns are 1 1/2". 

I like the style and my plan is to cast replacement black pawns to make this a usable set.  If that works, I'm thinking of casting an entire set with a different appearance (e.g., wood, metallic, or stone) as I think it would look better than the white and black plastic. 

The pawns are only 1.5", so I'm guessing that I can just use a Dixie cup when making the mold.  I'll need to plug the base of the pawn with some clay or something because the pieces are hollow.  My "to-do" list is to determine what materials I need, determine their quantities and cost, allocate space for a work area, and then execute the plan.  If this goes like my other plans, I should get around to it sometime by the end of the decade.

Clear Plastic dixie-sized cups work much better at releasing the silcone mold; whereas, wax-lined paper may bond to the silicone, and a pain to remove cleanly.

As you will be casting these pieces upside-down, the underside of the noses and chins will be the areas which will naturally try to trap bubbles. Since smaller quantities of resin fire-off slower than larger pours, and considering the undercuts do not appear all that extreme, you might want to try doing a partial fill, and then slowly rotate the mold by hand, helping any bubble to escape the nose/chin undercut areas; then, complete the fill and tap the mold on your table top to use a bit of vibration to help move and bubble out of the trap area - hopefully.

As I say, depending on the working time of your resin and the small amounts your will be pouring, you should have adequate time to manipulate your mold, without having to worry about making a mad dash for the pressure pot - presuming you will be using a pressure pot to cast in. 

As far as weighting your pieces, you can try 2-part Plumbers Putty from your local hardware store; see that doesn't give your pieces the heft you are desiring them to have.

My question to you is, since you asking about materials to plug your pieces with, I must presume you are going to hollow cast them(??).

Alternatively, you can do the casting in 2 separate pours. Pour would only up the where the base begins, or maybe only half way full, which you would allow to harden; then, to the cured partial casting, add your Plumbers Putty plug - keeping an allowance all the way around for some wall thickness of the base and the piece itself. Top the mold off with Pour #2, which will completely entomb the now hidden plug and complete the casting.

Hoping that's helpful to you.

Thank you, @CampwoodsRD.  You have been amazingly helpful!

I'm not planning to use a pressure pot.  I just don't want to incur that kind of expense until I know that this is a hobby that I want to pursue.  I found a few Robert Tolone videos where he shows how to cast without a pressure pot.  If I understand correctly, I might need to prepaint some resin into the mold even before using the method you describe in order to avoid air bubbles in the sharp features.  Even then, I might still get some air bubbles that I have to repair.  Since I'm only planning to cast 3 pawns in this initial project, I'm ok doing some manual touch up work (if that will work).  I'm fairly certain that this won't come out perfectly the first try and I'm ok with that.  A couple of malformed pawns is better than no pawns at all.

I'm not planning to hollow cast the pieces. Although I'd change my mind if you say that hollow casting is easier.  Is it?

I just meant that the originals are hollow (with open bottoms) and I don't want the silicone to enter the hollow bottom of the originals during the mold making process.  To prevent that from happening, I was thinking of plugging the hollow bases of the originals with clay before making the molds.  Watching some of the videos, it looks like I could just secure the bases to the bottom of the Dixie cup with wax and that should be sufficient to stop silicone from entering the base of the original.  The castings would then be solid.

I REALLY like your idea for using two pours to allow for the addition of weight to the pieces.  The originals are light as a feather and I'd like something with more heft.  I was also toying with the idea of (eventually) making a magnetic version of the set.  I'm assuming that I could add a magnet in the same way.  Is the join that forms from two separate pours as strong as just doing a single pour, or does that result in a weak point?

Again, thank you very much for all of your help!

You are more than welcome, I am glad to be a help to you!

Yes, correct; if you are not going to be using a pressure pot, then pre-painting with resin is the way to go; HOWEVER, then you are talking about making a 2-piece mold as opposed  to a 1-piece cut mold - the likes of which which Robert champions.... otherwise, if you want to pre-paint in a 1-piece mold, you going to make a small pour, and slowly turn it, rolling the resin around and around to coat the inside cavities while pushing air out... and pray.

Both Robert and Crafman have excellent videos on both types of molds. Just understand that a 2-Piece mold will require claying-in one side one side of each piece, pouring the first half, curing, removing ALL the clay, applying release agent, and then, pouring the second half to then cure. Of course, having 2 open mold halves which lay flat will allow you to pre-paint with resin and fight any bubbles which may try to form with vibration and or a pin to move or break them up. AND, you will most certainly get a parting-seam in your casting; but, these are easily scraped down flat with an Exacto knife or razor blade, if you catch the resin right after you de-mold.

Hollow Casting is a giant P.I.T.A. which I used to try to avoid at ALL costs LOL! Again, see Robert's video on his methods. 

You can secure the pieces right the inside of the plastic cup and not get any leakage provided you have a prefect seal. If it were me, considering how small the pieces are, I would simply clay-fill the base and then secure them down; as if they were solid-based to begin with, and side-step the whole business.

Yes, this exactly how you would entomb a magnet in the base; correct!

Provided you are NOT using two different mixtures with pigment to make two separate pours, the fact that the piece was created in 2 pours should be totally indistinguishable to the eye and hand. No structural difference as the material wholly bonds to itself.

If you are going to do multiple pours with anything added to your resin - such as: pigment, metal flake, etc. - be sure to blend the entire quantity you will need in both the A-side and the B-side, but only mix enough A&B together when you are going to pour one side. The unmixed A&B with the additives will be fine until you need to mix them together for your  next pour. This way, everything remains the same, and will look the same when you de-mold.

Since you are not going to be using a pressure pot, can I assume you will also not be using a vacuum chamber to de-gas your Silicone rubber? If so, please see Robert's video which is called some thing like 'No Vacuum, No Problem'.

Also, there are other types of non-industrial 2-part Si rubbers which do not require degassing with a vacuum chamber. Check with the folks at Smooth-On; and, I have seen these 'home crafter' type Si rubbers at craft stores... for people who want to make rubber molds, but do not want to make a mold shop and the 'big boy' equipment.

IIRC, Crafman seems to specialize in stuff from craft stores which is simple and requires little extra gear; whereas, Robert shows you how the Pros do it (with Pro Gear).

Spend a little time with Crafman, and see if his methods and materials are not more in-line with what you wish to get involved with at this early stage of your casting journey.

I will say this, there is demand for high-quality resin castings of otherwise unavailable or unobtainable Chessmen. So, if you make a go of it, you may find yourself with a fun and profitable side-line!

Let me know how else I may be of service to you.

Wow, thank you again.  You have been more help than I could have possibly imagined.  You're right that I do not plan to use a vacuum chamber, so I have added that video to my watch list and am going through some more Crafman videos.  It was by randomly clicking on a Crafman video that I started down this path; he made it look fun and not-so-daunting.

I doubt I'll get to the point where I am selling resin cast reproductions of vintage chess sets on Etsy, but you never know.  Baby steps.

Of course, pleased to share my knowledge with you; after all, it does no good locked in my own head.

I remember when I first got into the world of duplicating via Si molds and 2-part Urethane resins, it was mind boggling to me too; but, a very experienced Hollywood prop man befriended me, and shared his knowledge with me to get me up and going... and there was no internet like there is today back in '90, we had to talk over the phone, and send diagrams on graph paper through the mail - "Stone Knives and Bear Skin rugs!" LOL!

So, I'm really enjoying our conversation.

Agreed, "baby steps"; and therefore, would definitely find a method/materials which looks as simple as possible for Crafman - with no power equipment used -  and try just using supplies from the craft store and dollar store - of which he is a champion of.

You can always move up in size and sophistication.

Who knows, you may make the pieces you need and feel that you interest in casting Chessmen in resin as a hobby has been satisfied. Well, if so, that's okay too. I like to see people get what they want out of life.

And, if you should discover that casting Chessmen is the coolest thing since sliced bread, that's cool too.

Either way, and in the meantime, I'm happy to be a small part of your personal casting journey.