View Full Version : How to make a easy Casting of ours works

04-02-2012, 04:13 AM
A good way of " backup" copies of our work and at the same time to give the opportunity to others of being able to study the work of other engravers, is make castings (exact copy molds) of them. Castings are a great source of study to be able to learn engraving, because it offers to us the possibility of having in our hands exact copies of works of other engravers and studying them to the minimal detail and at the same time a great tool to be able to make a copy of the works that we do and that once sold ,in most of the case we will not return to see in our life. I am going to you to explain the technique and materials briefly. This he is casting of my last Hobo Nickel that I have been carving the past week in the Steve Lindsay's videochat.

Step 1

it is necessary to build a container where vertes the liquid silicone, in my case I have used plastcine clay for the base, a crystal like work plane and a glass of plastic for the sidewalls .....


we flatten the surface so that it is a straight plane with the aid of something of the same thickness and an aluminum tube in my case, but serves any thing .....


Once we have the flat base, we put the model to reproduce with the face " good" by above ..........


and we used the glass of plastic with the trimmed bottom to create the vertical walls of the mold being sunk to him a little in the plasticine clay.


Step 2


We are going to prepare now the mixture of liquid silicone, in my case I have used bicomponent silicone of the Smooth-On mark, exactly model OOMOO 25, this silicone has a very low viscosity, is mixed in equal parts 1:1 and the advantage is that it is very simple to use for people does not have experience with molds and practically does not create bubbles consequently is very indicated by these types of works.


We mix the two parts until we have a uniform color ..........


and we spill in the mold that we finished doing ....... we left silicone it frague by 75 minutes, in this east case type of silicone is quite fast.

Step 3


Spent 6 hours we stripped ...........


and now, we have our ready the silicone mold, which we have obtained is a negative clearly, it will serve that us to realise our definitive copy.

Step 4


In order to realise our positive we are going to use a liquid plastic resin in this case I I have used the mark Smooth-On Smooth-cast 300 is a very good plastic resin of a white color that it hardens to room temperature in 10 minutes, she is very fast, it leaves a working time of 3 minutes, but that sufficient for the type of works that we are going to realise


we make level the mold to have a perfectly horizontal plane


we mix as before the resins 1:1 is equal parts as in the previous case .......


and we spill in the silicone mold ........


when the resin start to harden we see as it begins to take a color white ........


after the ten minutes casting already he is ready, we can appreciate since he has become totally white.


We strip and already we have our exact plastic resin copy!


Now we only have left to give the finished one casting, in this case I am going to do the same with the original one, because clearly if you need thought to make a copy the model must be perfectly clean, for that, I use latex gloves for protection (the ink spot) q-tips to paint and etching calcographic ink to obtain all the details, as much for casting that for the original one.


we cover with in the nickel and the casting and we retired the leftover with a piece of newspaper paper or with a soft paper.

And here the result .....

The Casting


The Original Nickel


As you can observe the reproduction of the detail is perfect and now you have a copy of your work;)
We can to realise hundreds of copies with the same mold, to make that you only follow the instructions of the manufacturer to keep from suitable way the molds

I hope is to you of utility.

Expecially thank to Gert to eplain to me how make it and where buy all the components heare in Europe!!!
And To Steve too to allow me post it!

Superior Design
04-02-2012, 04:22 AM
Paolo great tutorial!
The casting looks great and exactly like the original piece. It was nice to see you working on it in the conference room.
Thanks again for all of your explanations!

04-02-2012, 04:23 AM
Mrthe, Thanks for posting this. A lot of information here. I'm sure a lot of us can use this helpful information. Gary

JJ Roberts
04-02-2012, 05:33 AM
mrthe,Nice carving of your hobo nickel & casting,I think you could save a lot of silicne rubber compound if you just set the nickel on a peace of class and rolled out your clay and made a frame around the nickel and then poured in the rubber compound you could get mileage out of your rubber mold compound.My molds are only 1/8" thick saving a lot of rubber compound,hope this helps.:thumb[1]: J.J.

04-02-2012, 05:49 AM
yes JJ in the next i will make the molds more thick ;) this one is too high for the size of the nickel ,Thank you ;)

Willem Parel
04-02-2012, 06:09 AM
Thank you mrthe for this tutorial !!!:thumb[1]:

Carol Carter-Wientjes
04-02-2012, 06:55 AM
Mrthe, An excellent tutorial and thank you for doing it! It's amazing just how well this works so I'm anxious to try it as well.

Always enjoy seeing your nickels too :) CaroL

04-02-2012, 08:44 AM

A great tutorial Mrthe,Thank you.


04-02-2012, 12:21 PM
Thank you, Love the gauze.
What durometer is that rubber you're using?
Also, is it a special kind ov plastecene? I have t touchd plastecene for years because it loosened my molds.. That said, I've had mold poisenings over the years, for verity of things.... Perhaps my brand is just over sensitive?
Anyways, looks great.

04-02-2012, 01:04 PM
The rubber is a shore A hardness 25,no problem with the plasticine,all the way you can make the mold walls and the base with a lot of materials,like say JJ you can cast directly the silicone using the glass like a base and make the walls with lego for example ,is a easy ang good tip use it in this way:


and use the plasticine only in the external sides to seal it ;)

04-02-2012, 01:19 PM
Thank you for that! Very very helpful!:thumb[1]:
I hope someone makes this a sticky. :thankyou[1]:

04-03-2012, 11:27 AM
Awesome tutorial! And great subject matter for the nickel, too. ;)

04-03-2012, 11:41 AM
Thanks to al for the nice comments,i'm glad to see that is helpfull for us .

Hey Kaitlin i'm happy to see that you like the subject too hehehe ;)

Sam Welch
04-03-2012, 12:13 PM
I did a siminar on casting many years ago for FEGA. It used to be available on VHS but I do not know if it is still available. Check www.FEGA.com

04-04-2012, 06:05 AM
That was wonderful! Now I just need to track down the components. Thanks for such a useful post.

JJ Roberts
04-04-2012, 07:37 AM
myazel,You can get the components for casting from Smooth-On Easton Pa. phone 610-252-5800,they will refer you to a dealer in your state.:cheers2[1]:J.J.

bram ramon
04-04-2012, 09:50 AM
Gracias amigo! Great turtorial!:whoo[1]:

04-04-2012, 02:19 PM
Gracias amigo! Great turtorial!:whoo[1]:

De rien mon amis ;)

04-07-2012, 11:44 AM

Paolo sent me his original mummy nickel in the mail!!

Paolo, you are incredibly talented and generous. The pictures do not capture how sculptural the engraving is-- beautiful work. And you even wrote a tutorial to help share your knowledge with others.

I just completed my Master's thesis work dealing with an Egyptian mummy-- The nickel is a really neat memento to go along with it. Thank you so much!!!


04-07-2012, 12:33 PM
Of nothing :) i'm very happy to know that the nickel are arrived save in yours hands and you have appreciate and like it, is a pleasure for me share my little knowledes with the folks of the forum ,since they do with me,and thank you very much for your nice words are an encouragement in my engraving learning way for me ;)
I wish you all the best for your master's thesis and your future!

04-10-2012, 12:42 AM
What a brilliant tutorial. Thank you. :thumb[1]:


04-10-2012, 10:44 AM
Thank You for the Fine Tutorial mrthe!

04-12-2012, 01:31 PM
Thanks mrthe,

I believe it will be some time before I have anything worthy of casting but Ill be ready if I need it.

Thanks again, Bob

Daniel Houwer
04-14-2012, 03:36 AM
Very nice tutorial Mrthe!
The lego is a wonderfull idea. For small things the cups or anything works fine. For bigger castings I have been fooling around with strips of wood gleud together or held together with ducktape. It works but takes to much time.
The lego seems to be the perfect solution for that.
My stuff for the mold is pink though. I am wondering if there is any difference. Yours cures a lot faster, mine takes 16 hours. Could you tell me what you pay for it?

04-14-2012, 03:54 AM
the 1 liter pack of rubber cost around 25 euros
the 1 kg liter plastic around 18 euros

Daniel Houwer
04-14-2012, 04:14 AM
Wow, I have to check but i am pritty sure I payed like 60,- for the both.

04-14-2012, 04:44 AM
Daniel the same shop heare in barcelona where i buy this product have another one in netherland if you want i can pass to you the info i will entry in the video chat in 5 minutes ;)

04-14-2012, 08:47 AM
Sorry i had made a mistake in the tutorial,the rubber that i use in it,the oomoo 25 cure in 75 minutes not 6 hours sorry,i have correct it ;)

04-15-2012, 06:53 AM
JJ i Have followed your advice,now i only need 5 ml for one mold,with one liter i can make 200 molds! hehe thank you ;)


JJ Roberts
04-15-2012, 07:41 AM
Paolo,Glad I was able to help you with advice on using less molding compond for your coin castings,wish are looking great.:thumb[1]:Keep up the good work. J.J.

04-15-2012, 07:45 AM
JJ you always help us with your knowledges and experience!
thank you very much another time ;)

07-01-2012, 10:07 PM
I am not much of an engraver, the work on you hobo nickel is fantastic. I am a jeweler with 35 years experience. I do stone setting CAD and mold making. I have found this material to be great for a quick simple mold http://www.riogrande.com/Product/Rio-Cold-Mold-1-oz/701042?pos=2
For a simple fast mold it works great just kneed the 2 parts together like clay. Lay your coin on a clean flat suface press it on and about 5 minutes later you have a mold with 0% shrinkage..... FWIW

07-09-2012, 05:17 AM
So, where do you get this stuff from in Europe? :)

07-09-2012, 05:32 AM
I buy it in my city Barcelona,that os the dealer for Spain
Heare you can find the dealer most near to your city
I have see that there was one in Estonia but the link don't work,the Spanish one all the way send to Europe if you want buy in Spain i think that will not have problems ;)

07-01-2014, 06:38 PM
I make musical instruments in the same manor. I build wooden masters and build silicone molds from smooth on Platinum silicone and cast them in a pressure chamber. The pictures from this post where gone.