Resin Alternatives for Small Molds

[Snake45]

I occasionally have to make a small mold (think emblems and things of that nature) out of either foil or common silicone sealer. Not wanting to mess with resin, I've had luck filling such small molds with J-B weld, common epoxy, and even carpenter's sandable wood glue (cures harder than common Elmer's, but requires several thin layers over several days). Now I'm interested in doing some larger parts (specifically, rocker panels for C2 Corvettes). Been wondering if something else might work better for these. How about hot glue? What about melting styrene sprue in something like a large spoon and pouring that in? Has anyone tried either of these materials to make small parts?

And before someone says "Just use resin," let me reiterate that I'm looking for ALTERNATIVES to resin. I don't want to get into resin for various reasons if there's any way to avoid working with the stuff.

[gtx6970]

Same here. Think I want to get into making small pieces , ( mirrors, door handles , emblems , arm rest pads etc )

This is just a thought. But I've repaired 1/1 plastic grilles by taking a baby food jar fill it about half way with scrap pieces of another grille and pour in acetone. Put the lid on and let it sit maybe 24  hours or so .

 

It melts the plastic into this glue like substance and works perfectly for 1/1 grilles. And I keep thinking about trying it with stryene

Edited December 24, 2016 by gtx6970

[Xingu]

There are folks who make a witch's brew of chemically melted styrene and use it for body filler, so it may be possible. Just need to figure out how to get it to release properly.

[StevenGuthmiller]

How about "Laser Bond" or "Bondic"?

I've been making small parts with Laser Bond for some time.

It works well.

 

Steve

[Snake45]

Same here. Think I want to get into making small pieces , ( mirrors, door handles , emblems , arm rest pads etc )

This is just a thought. But I've repaired 1/1 plastic grilles by taking a baby food jar fill it about half way with scrap pieces of another grille and pour in acetone. Put the lid on and let it sit maybe 24  hours or so .

 

It melts the plastic into this glue like substance and works perfectly for 1/1 grilles. And I keep thinking about trying it with stryene

I used to use a lot of that stuff for putty. It would work for this application, BUT I found for it to properly cure/dry, you have to use very thin layers. For what I want to do, it would take a month of applying and drying.

Also, I've tried this before on a small part, and found that the cured part was VERY brittle.

[Snake45]

How about "Laser Bond" or "Bondic"?

I've been making small parts with Laser Bond for some time.

It works well.

 

Steve

Now this is an idea! I'm going to have to check that stuff out.

[John Pol]

What do you guys use to make your copys of badges and door handles and that

[Snake45]

What do you guys use to make your copys of badges and door handles and that

Either common household kitchen foil (especially if the part needs to be "chrome" anyway), or in other cases Permatex black silicone.

[Mike Kucaba]

I'' ve mentioned it before  use 30 minute epoxy mixed with micro balloons.

 

[Snake45]

I'' ve mentioned it before  use 30 minute epoxy mixed with micro balloons.

 

The microballoons isn't a bad idea, if I can find any locally. Thanks!

[Ace-Garageguy]

The cheapest and most readily available home-brew mold-making material that actually works is plaster of Paris.

Like all home-brew cheapo alternatives to using the real stuff, it has its limitations...

Liquid brushable latex can also be used effectively, and is widely used for mold-making, but because it also dries by evaporation (like dissolved styrene) it has to be applied in relatively thin layers.

I've seen hundreds of second-rate and downright awful results using both, and even a few decent ones.  

What I've never understood is the widespread reluctance to use commercially available materials that work perfectly, every time.

 

Edited December 25, 2016 by Ace-Garageguy

[Steven Zimmerman]

You can purchase resin at Hobby Lobby w/ coupon for around $14 bucks. I understand wanting to find other alternatives, but why ?

[StevenGuthmiller]

You can purchase resin at Hobby Lobby w/ coupon for around $14 bucks. I understand wanting to find other alternatives, but why ?

I use resin as well, depending on what I want to make, but some of the alternatives do have their virtues.

The nice thing about using something like Laser Bond for casting small parts is, the parts can be cast instantly.

If you're in need of something "right now" you can avoid waiting for curing times & have the part in hand & ready to use in seconds.

Plus, If I'm just casting a set of window cranks, It's a lot less "mess" than dealing with mixing 2 part resins & cleaning up afterwards.

 

Steve

[Ace-Garageguy]

I use resin as well, depending on what I want to make, but some of the alternatives do have their virtues.

The nice thing about using something like Laser Bond for casting small parts is, the parts can be cast instantly.

If you're in need of something "right now" you can avoid waiting for curing times & have the part in hand & ready to use in seconds.

Plus, If I'm just casting a set of window cranks, It's a lot less "mess" than dealing with mixing 2 part resins & cleaning up afterwards.

OK, sounds reasonable.

What kind of mold-release do you use for these alternative materials? 

I assume the UV-curing resins stick both to styrene and to themselves, so a mold release would be required...correct?

[Snake45]

So far, I've never had anything stick to the Permatex Black silicone*, and I've never used mold release. It just peels right away.

If I'm "casting" into a foil-copy mold for an emblem, I'm not worried about release, as the foil is the top "skin" of the part.

*Except itself. A second layer of the stuff will bond to the first PERMANENTLY, as if it had been done as one piece to start with.

[Jon Haigwood]

I mix baby/talcum power with superglue as a filler. Dries fast an works like regular model plastic. May work for smaller items 

 

Then there is Sprue-Glue   https://www.youtube.com/watch?v=8E64rsyuTo8

Edited December 25, 2016 by Jon Haigwood

[gtx6970]

Im gonna have to find this laser bond stuff

 

Ive got some small emblems i want to make...and interior window cranks

 

 

[Mike Chernecki]

This is interesting, one of my projects is the AMT '72 Blazer. I have wanted to cast the side marker lights and a few other bits on the body. So if I put a dab of Permatex Black silicone directly on the body, it will peel off without damage to the kit body? Or do I need to apply the kitchen foil first?

[peteski]

For foil-casting things like emblems or door handles I used 5-minute epoxy.

 

I don't see any viable alternatives for larger pieces. Other materials either shrink when drying, take forever to dry, or are too soft/flexible or fragile to be useful. 2-part resin is IMO the only option.  It hardens by chemical reaction (not by evaporation of a solvent), it is very thin when liquid (allowing it to easily fill the mold) and hardens to a durable material.

Edited December 26, 2016 by peteski

[Foxer]

OK, sounds reasonable.

What kind of mold-release do you use for these alternative materials? 

I assume the UV-curing resins stick both to styrene and to themselves, so a mold release would be required...correct?

I use Bondic a lot for small parts and no mold release is required. It is advertised as a "glue" but it hardly sticks to anything. It does come out with a slightly sticky feel and clouds when touched so a spray with acrylic clear takes care of that. This stuff is so easy and quick to use that I don't get why everyone keeps looking for something to cast small parts when this material is available. It should be in everyone's toolbox. Resin is the most user-unfriendly material I ever used ... unequal mixing ratio, VERY expensive, especially for small parts, as shelf life makes me throw out 95% of it, bubbles everywhere to fix, wait for it to cure and just plain nasty stuff, IMO.

I use Silicon rubber 2-part molding putty

Edited December 27, 2016 by Foxer

[Snake45]

This is interesting, one of my projects is the AMT '72 Blazer. I have wanted to cast the side marker lights and a few other bits on the body. So if I put a dab of Permatex Black silicone directly on the body, it will peel off without damage to the kit body? Or do I need to apply the kitchen foil first?

For side markers, I wouldn't even use silicone. I'd just make a foil copy, and then put J-B Weld (or other epoxy), or yellow carpenter's glue, or superglue gel right into the backside of the foil. When it's cured, trim the foil back to the part and glue it on your model. I've done this kind of thing many times.

I've only had the Permatex sort-of stick on me once, and I think that was an old tube that was going bad. Get some and experiment on things like the tops of chassis and the undersides of interior tubs until you're comfortable with it. The smoother the plastic is, the less chance the silicone will stick to it. (I've never tried it over primer so have no idea what it would do in that case.)

[Snake45]

 Resin is the most user-unfriendly material I ever used ... unequal mixing ratio, VERY expensive, especially for small parts, as shelf life makes me throw out 95% of it, bubbles everywhere to fix, wait for it to cure and just plain nasty stuff, IMO.

 

We are on the same page, my friend.

[Steven Zimmerman]

We are on the same page, my friend.

To each his own, I guess....I have never seen resin offered with any mixing ratio than 1 to one, and it's very forgiving, you can eyeball it in a clear mixing cup, no need to measure it exactly by weight or eyedropper ;  As far as price, you can buy 'amazing resin' at hobby lobby , with the 40% off coupon for about the same price as one of those glue / infra - red pens, and you get a lot more.  Bubbles can be frustrating, but learning how to deal with that is easy, using a toothpick, and mold filling procedure. Cures in less than a half hour, with you can accelerate with a food dehydrator; most resin has a year shelf life, as long as you keep it 'closed', and storing in the refrigerator can extend that. IMHO, there is no other product I know of that closely resembles styrene, either in stability once hard, workability, tensile strength, sands and preps like styrene, etc.. with the added benefit that you can paint it with just about anything - lacquer, enamel, acrylic;  and it reacts to none of those........ As far as being 'just plain nasty'.......no worse than superglue, or two part epoxy. Just like everything else in this hobby, use of resin has a learning curve. Did your first paint job come out perfect, or did you learn better techniques, etc,  as you progressed . I do realize, that coming from someone who pours gallons of resin a year, vs. one who just wants a quick, easy one time fix,  resin may not be the answer....that whatever works is OK  for you, .....'Z'

 

[Snake45]

 I do realize, that coming from someone who pours gallons of resin a year, vs. one who just wants a quick, easy one time fix,  resin may not be the answer.

 

Hence my original post.

[StevenGuthmiller]

I use Bondic a lot for small parts and no mold release is required. It is advertised as a "glue" but it hardly sticks to anything. It does come out with a slightly sticky feel and clouds when touched so a spray with acrylic clear takes care of that. This stuff is so easy and quick to use that I don't get why everyone keeps looking for something to cast small parts when this material is available.

I use Silicon rubber 2-part molding putty

Ditto.

I use Laser Bond, but it's basically the same stuff as Bondic.

I also use the molding putty.

I've not gotten into the foil molding.

I just mold the parts in Laser Bond & then spray the chrome on with Alclad.

 

Steve