Well as they say there is allways a first time. Today was the day! I made a copy of a Faller porsche 911 for my son.It was going to be a 2 piece mold but I screwed up and did not get the seal under the car good and the rubber got under it bad so it's a slosh cast mold.
Now for a few questions,
Where can I buy small stir sticks? I tried a hardware store ng. Also I am using the smooth cast starter kit, do I need to prime this resin before I spray paint? I bought krylon fusion paint, anybody ues it? Send all help!! Thanks!

Well as they say there is allways a first time. Today was the day! I made a copy of a Faller porsche 911 for my son.It was going to be a 2 piece mold but I screwed up and did not get the seal under the car good and the rubber got under it bad so it's a slosh cast mold.
Now for a few questions,
Where can I buy small stir sticks? I tried a hardware store ng. Also I am using the smooth cast starter kit, do I need to prime this resin before I spray paint? I bought krylon fusion paint, anybody ues it? Send all help!! Thanks!

You could always re-seal the master into the female side of the mold using a little vaseline and give it another shot.

Hobby or craft stores usually have nice big packs of popsicle sticks, thats what I used when I was doing a lot of casting. Need to get back into it, I got tons of diecasts sitting around waiting for some silicone.

What brand resin are you using? I used either smooth on or alumilite, and Id just give mine a good sand down with 400 grit then airbrush on model masters acrylic with good adhesion. But mine dont get raced hard or often so primer never hurts. Fusion is supposed to chemically bond to most plastics though. Id say pop a few test mules and try different techniques. This will serve 2 purposes: You get to figure out what will hold up, and gives you an excuse to ride a few cars good and hard!

Stir sticks you don't need no stinking stir sticks sticks :)

Remember silicone only sticks to silicone. I reach in the kitchen drawer and get me a butter knife preferably one without and cutting edges. Works great. After stirring just wipe it off with a paper towel. Any silicone you miss will peel right off when it dries. Also McDonald's plastic knifes are smooth with no edge. Next time you take the kids for breakfast pickup a few.

Roger Corrie

Sticks???
I agree with above. I go to the local Michael's and buy a "box" of pop sickle sticks. I think the box I bought was 1000 for $3. I still haven't put a dent in the total yet. I'm cheap, so I use the stick twice. I stir with one end, then the next go-around, I stir with the other end before tossing in the trash.

Mixing cups???

Go to the Jewel (or any like grocery store). I go into the party section usually by the liqour. I buy 50 count clear plastic shot glasses for $2.50. You can see your two part pour and they are usually smooth without the graduates lines that interfer with stirring.

Two Part mold suggestion....

Once I had the RTV sneak past the body subject causing the RTV male part to stick to the femalr part. What a mess. I pour the female part over the body subject in the mold box (legos). Once that is cured, I remove the female mold from the box, but obviously still leave the body inside the femaile mold. This is the important part. I generously coat the inside of the body and female RTV with vasiline. I even make sure I get enough vasiline to where it seals the gaps, if any, between the body and the female RTV mold. This way nothing RTV-wise sneaks to touch the other RTV. Hope that helped?

Gar

Mineral oil, or pam non stick cooking oil works great also for either coating the master copy or keeping the RTV silicone from sticking together. I had a small diameter wood dowell rod that I cut into about 6" lengths for stir sticks. I colored my resin with enamel paint so I didn't have to worry about painting or chipping etc. The sticks I would let dry because of the colored resin and I would cut the hardened resin off periodically with my pocket knife. Bought mixing cups for resin mixing at hobby lobby. Would let the excess mixture dry and it would peel right out, so they will last forever probably. Used a plastic bowl for the RTV. Same thing, the RTV would peel right out after it got hard. The Finish top coat wound be future floor wax. I will have to get some pictures up of some of my castings. Been a few years, have to dig em out. Sorry for the looong read. TomH

You could always re-seal the master into the female side of the mold using a little vaseline and give it another shot.

Hobby or craft stores usually have nice big packs of popsicle sticks, thats what I used when I was doing a lot of casting. Need to get back into it, I got tons of diecasts sitting around waiting for some silicone.

What brand resin are you using? I used either smooth on or alumilite, and Id just give mine a good sand down with 400 grit then airbrush on model masters acrylic with good adhesion. But mine dont get raced hard or often so primer never hurts. Fusion is supposed to chemically bond to most plastics though. Id say pop a few test mules and try different techniques. This will serve 2 purposes: You get to figure out what will hold up, and gives you an excuse to ride a few cars good and hard!

I took Rogers advice and started with the smooth on kit for newbies!

Stir sticks you don't need no stinking stir sticks sticks :)

Remember silicone only sticks to silicone. I reach in the kitchen drawer and get me a butter knife preferably one without and cutting edges. Works great. After stirring just wipe it off with a paper towel. Any silicone you miss will peel right off when it dries. Also McDonald's plastic knifes are smooth with no edge. Next time you take the kids for breakfast pickup a few.

Roger Corrie

I go buy a good knife thanks

Sticks???
I agree with above. I go to the local Michael's and buy a "box" of pop sickle sticks. I think the box I bought was 1000 for $3. I still haven't put a dent in the total yet. I'm cheap, so I use the stick twice. I stir with one end, then the next go-around, I stir with the other end before tossing in the trash.

Mixing cups???

Go to the Jewel (or any like grocery store). I go into the party section usually by the liqour. I buy 50 count clear plastic shot glasses for $2.50. You can see your two part pour and they are usually smooth without the graduates lines that interfer with stirring.

Two Part mold suggestion....

Once I had the RTV sneak past the body subject causing the RTV male part to stick to the femalr part. What a mess. I pour the female part over the body subject in the mold box (legos). Once that is cured, I remove the female mold from the box, but obviously still leave the body inside the femaile mold. This is the important part. I generously coat the inside of the body and female RTV with vasiline. I even make sure I get enough vasiline to where it seals the gaps, if any, between the body and the female RTV mold. This way nothing RTV-wise sneaks to touch the other RTV. Hope that helped?

Gar

The female mold. the silicone seeped under the clay, I tried to clean it up with an exacto knife ng. It makes nice porshes though. just need to do the wiggle the repour then grind out.

I took Rogers advice and started with the smooth on kit for newbies!

Good move, he steered you in the right direction. It has a good chunk of the main stuff you need to get started. The other thing Id suggest is getting ahold of some legos and a base plate. Thats the only mold box you'll ever need. You can score deals on the 'bay for that.

This has been great advice so far!!! :thumbsup:

If you're in doubt about two part RTV molds, I put up a photo tutorial over on a Yahoo group site.

Go to Yahoo.com, find the link "groups" and register. Use the search to find the site/page "hoslotcarcasting", once registered to their page, go to the "photos" link, then to the second page. The name of the album in "Mold Making Process". Or, once registered, use this link;
http://ph.groups.yahoo.com/group/hoslotcarcasting/photos/browse/21d7

The typed description is short, but the photos I put up may be worth a 1000 words to you. It will also show the use of Legos for the mold box.

Gary

This has been great advice so far!!! :thumbsup:

If you're in doubt about two part RTV molds, I put up a photo tutorial over on a Yahoo group site.

Go to Yahoo.com, find the link "groups" and register. Use the search to find the site/page "hoslotcarcasting", once registered to their page, go to the "photos" link, then to the second page. The name of the album in "Mold Making Process". Or, once registered, use this link;
http://ph.groups.yahoo.com/group/hoslotcarcasting/photos/browse/21d7

The typed description is short, but the photos I put up may be worth a 1000 words to you. It will also show the use of Legos for the mold box.

Gary

I just read you artical. Why didn't you pour the resin then place the male 1/2 in then top off the resin? (squish it in)

I am searching for another thread and stumbled on this one...

Lots of good information here so I am ploping it back into the NOW. lol

The Faller Porsche body is thin to begin with and started out with problems but, now can pull a nice one out with some carfull twist and tugs.

http://i59.photobucket.com/albums/g282/bobhch/adac3.jpg

Bob...good casting 101 information here...zilla

I just read you artical. Why didn't you pour the resin then place the male 1/2 in then top off the resin? (squish it in)

T-Jet, sorry for the late response. I completely missed this thread.

When I first started casting I did just as you stated. I would pour in a certain amount of resin into the female mold, slosh it around to coat the surface, then slowly push in the male part of the mold. However, I found that most times when I squish or push the male part into the female part it would catch air bubbles. The best way to describe why I pour from one end, is that it forces the air out the opposite end. I think it is referred to as a "Gravity Pour"? The only times I get bubble issues now, is in the little winglets or sharp corners where the resin doesn't get a natural smooth flow. Here's what I do now. Once my resin is mixed, I dip my mixing stick in the resin and let it drip into a corner or winglet "undercut" so I can turn the mold to let the resin flow into that area. I then place the male part into the female part. When I start to pour the resin into one end, I use the pop sickle stick as a ramp to pour the resin down while also using the stick to slightly pry apart the two mold halves. This creates a slightly larger pouring mouth without getting the two halves too far apart to catch or create a air pocket. Sometimes I just use the stick as a pry to make a bigger pour opening and pour the resin directly into the opening without the resin touching the stick.

Here is another tip. When I cut my vents and pour the first 2-3 bodies, I experiment by pouring the resin from the front end of the body/mold the first pour, then the rear end the second pour. Because of the shape of some bodies, I find the resin flows better from one end better than it does from the other end. After a few bodies, I will mark the pouring end that works the best. If I ever duplicate that particular body's mold due to demand, I will start the pouring on the new mold from the better end. Saves time and resin materials once you get familar with the pour characteristics of a certain shaped body. Hope that tip helps?

Gar