Resin Casting Part II Making the part

edit by jay: in case you missed part I: Resin Casting Part I - Making the mold (http://www.automotiveforums.com/vbulletin/showthread.php?t=188447)

Okay folks as promised Part II

In Part I we discussed making the mold. 1 piece flat molds are pretty easy. For multiple piece molds you need to think about how the mold will come apart to allow the master and subsequent cast parts to be removed. Don't follow me? Take a look at a kit body for example. Those unsightly seams we all have to sand off are actually mold lines where the pieces of a mold meet. Now visualize all the pieces that would be required.
Another thing about multi piece molds is that you need a way to pour the resin in and a way for the air it displaces to get out ( vent ) otherwise you will have huge air pockets in the finished piece.

Lets look at the 2 piece tire mold I made. Remember the nails that held it in place while I poured the first half? I left 2 in when I did the second half and now its time to enlarge the holes they left and clean them up a bit.Carefully cut the groove wider with an Exacto
http://images54.fotki.com/v1613/photos/1/11686/415169/IMGP1514-vi.jpg
When the halves are rejoined they should look like this
http://images23.fotki.com/v860/photos/1/11686/415169/IMGP1515-vi.jpg
Now that that is ready a few more words on mulit piece molds. Sometiems even with a 2 piece you need a way to hold the piece up while Part 1 is poured, for this surfboard I made a 1/4 thick slab of clay on my glass and buried and blended the surfboard into it right up to the part ( halfway ) line.I poured the first half then turned the piece over, removed the clay added a few more legos to make the form deeper and then poured the second half.As you can see I also used a few small Legos as keys to hold the 2 halves together
http://images116.fotki.com/v699/photos/1/11686/415169/IMGP1513-vi.jpg
If you want to learn more about multi piece molds I suggest you do some research into sculpture techniques and so on, theres way more than I can cover here.

Allright time to pour. The same rules apply here, clean work area, clean molds, air bubbles are your enemy. Oh wait did I mention air bubbles are bad?!? LOL
Prep all of your molds, check for dirt, stray bits of RTV, Cat hairs ......
You don't wnat anything to mess up your part.
Now its time to add the mold release. Careful not too much, if it puddles it willl create a pocket in your completed part. And as always spray in a well ventilated area and use a mask. I should point out DO NOT DO THIS ANYWHERE NEAR YOUR PAINTING AREA!!!!!m Airborne silicone spray particles in your paint area will really screw up a good paint job.
http://images116.fotki.com/v700/photos/1/11686/415169/IMGP1518-vi.jpg
I like to hold the 2 piecers together with a few rubber bands, not too tight you don't want to distort the mold
http://images23.fotki.com/v859/photos/1/11686/415169/IMGP1519-vi.jpg
I am currrently using a 1 to 1 thin clear resin ( cures white ) that sets in about 40 minutes. Again accuracy is the key, if it says 1 to 1 it means 1 to 1. Pour equal amounts in seperate containers and then combine in a third. Gently mix with a craft stick and avoid introducing any air into the mix.It should be poured in a thin stream just like the RTV, remember this helps to eliminate any smalll air bubbles.
If any do occur-such as this wheel that seems prone to air pockets in the center cap- I found you can use a big straight pin to coax it to the surface
http://images55.fotki.com/v1618/photos/1/11686/415169/IMGP1520-vi.jpg
As you can see I overfill the one piece flat molds slightly. Then I take a credit card ( save the fakes that come in the mail with all those annoying credit card offers ) and gently scrape off the excess leaving a nice clean flat back
http://images17.fotki.com/v1621/photos/1/11686/415169/IMGP1521-vi.jpg
http://images56.fotki.com/v1602/photos/1/11686/415169/IMGP1522-vi.jpg
For multi piece molds I like to use a tiny funnel to direct the resin into the hole
http://images54.fotki.com/v460/photos/1/11686/415169/IMGP1523-vi.jpg
Fill until the excess comes out the vent hole(s)
http://images21.fotki.com/v843/photos/1/11686/415169/IMGP1524-vi.jpg

Sit back and wait, this is where the patience comes into play.
Soon you will notice the resin begin to kick and turn slightly white
http://images54.fotki.com/v460/photos/1/11686/415169/IMGP1525-vi.jpg
http://images55.fotki.com/v1618/photos/1/11686/415169/IMGP1526-vi.jpg
a little more but not quite cured
http://images114.fotki.com/v288/photos/1/11686/415169/IMGP1527-vi.jpg
http://images17.fotki.com/v1621/photos/1/11686/415169/IMGP1528-vi.jpg
When it turns completely white its almost done. Just to be safe wait another 10 or 15 minutes because if its still warm from the curing action when you remove the part it can warp.
http://images59.fotki.com/v419/photos/1/11686/415169/IMGP1529-vi.jpg
Tired of wating? Gently demold.
http://images114.fotki.com/v271/photos/1/11686/415169/IMGP1530-vi.jpg
Big Brakes anyone? The light flashing can easily be sanded off
http://images56.fotki.com/v702/photos/1/11686/415169/IMGP1531-vi.jpg
Did you say slicks ?
http://images55.fotki.com/v1604/photos/1/11686/415169/IMGP1532-vi.jpg

There you have it, now its time to clean em up and paint em. You will need toi remove the mold release, I do this by washing several times in a degreasing dish soap.
You may have some very thin flash on the back of the pieces from the 1 piece flat molds, this can happen when you scrape the excess resin. Its easily taken off by sanding the back of the piece on a flat surface. Fill any pinholes with putty ( I use Bondo Glazing Putty ) Sand any seams flat.
Follow your normal painting steps.
I have been thinking that since the tires are cast in white I could paint them the correct shade of black and then sand back through to the white where the lettering is. Hopefully producing a nice tire with raised white lettering.

Peace and Good Luck
Dag

Thanks for sharing this with us!

Great work! :)

how did you make the molds?? It looks very nice

nvm about the question. it looks great,makes me wana do it myself!!

This is a F*cken tight ass how to DAG65 now i can mold seats and wheels. Im going to get all of the supplies tommorow and start making seats, Wheels, Brembo Brakes and Engine parts :biggrin::biggrin::biggrin:

really well made.. Hope this one found id way to the FAQ..

man..40 minutes to cure??? the resin i use cures in 10..and it's the thin clear/white stuff.

really well made.. Hope this one found id way to the FAQ..
it better :smile:

this will help thanks i always wonders bout that

nice it will be very usefull!

:iagree:

Thanks! Thanks! Thanks! Thanks! Thanks! Thanks!

Great tutorial.Plan on using it.

man..40 minutes to cure??? the resin i use cures in 10..and it's the thin clear/white stuff.
Like I mentioned before there are all types and each has its own properties, I prefer one that is a little slower setting as it gives me a little more pour and fiddle time. As it is there is only a 7 minute pot life befor it starts to kick

Great tutorial, I was at the store today talking about casting and the tech told me that you can cast urethane for rubber like tires, and you can tint it black.

Great tutorial, I was at the store today talking about casting and the tech told me that you can cast urethane for rubber like tires, and you can tint it black.
Yes , there are actually two part resis that remain somewhat soft, almost like hard foam rubber.

Do you think it would b possible to make a whole body using that method?

Do you think it would b possible to make a whole body using that method?
Bodies require a more complex mold however the methods and materials are the same

cool

holy shit, old thread batman

awsome!

Amazing tutorial. Thanks for sharing this with us! :)

Very cool, awsome tutorial,
I would love to do this, so i can replicate so many cars.
But just don't have the money/place/time to do this.

sorry for the threadbump i haven't seen any answer to this yet and this seems to be the best thread to ask it.

would it be possible to make a negative of the part that you're casting? example, use a left hand as master and as end result, the right hand is made?

would it be possible to make a negative of the part that you're casting? example, use a left hand as master and as end result, the right hand is made?

A negative is quite different to a mirror image or the symmetrical opposite of the part.

To answer your question, if a part is handed (LH is the opposite of the RH), there is no way I know of to make both parts from one, in your case, LH master.

thanks ray!

is there any resin that cures to chrome?

is there any resin that cures to chrome?

If you're referring to a chrome finish, no there is not. This is why chrome paints and chrome plating exists.

In future, please don't revive old threads for questions such as this.

Thanks for the info on how to cast....this will really come in handy duplicating a gear in my RC......

lol....2 gears....1 stripped....1 handmade from bigger one lasted 1 day....gonna cast it now! last longer!! lol

Oops....double post....lol

hi the photo's appear to be absent front the resin casting tutorial part 2.
can this be ammended as i'm using it as a guide for anoher young modeller..

thanks and brilliant tut. by the way

test

http://images55.fotki.com/v54/photos/1/11686/415169/IMGP1495-vi.jpg

hi the photo's appear to be absent front the resin casting tutorial part 2.
can this be ammended as i'm using it as a guide for anoher young modeller..

thanks and brilliant tut. by the way

Looks like the fotki links changed over the years. Wow has it been 7 since I wrote this thing, dang.
Well I fixed up the links for everyone.
Peace

So, are you back, or have you just been quietly lurking all this time?

So, are you back, or have you just been quietly lurking all this time?

Just dropped in to fix a few links to Fotki by request. My modelling projects are full scale these days. Hope to get the Ghia done this year.

this alumilite resin will work for that? :confused:

wow, I remember this thread; it was one of the two I refered to when I first started casting my own bits and pieces.