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Anyone hear of a Epoxy & Aluminum Foil Emblem Copy Technique?


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Has anyone heard of a technique using aluminum foil and epoxy to make emblem badges & name script copies for cars? I remember something in an old defunct forum, about making copies of your emblems and scripts with foil and expoxy, so you can save the detail of emblems & scripts when doing lots of layers of painting. Basically you would just paint in the emblems or scripts or use bmf on your "epoxy copy", and then glue them on the appropriate placements when you're done. Anyone out there know how this is done exactly?

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Yeah I was thinking something like a rubber latex would work better than using foil for it. The epoxy I'm sure would work fine in your mold. I've heard of people using it for small parts in molds. I've also heard of a product called Amazing Putty, its a two part putty you can make a mold of. I'm thinking that might work easier than trying foil.

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There might be a few topics here on it I will have to search through. I know of one for sure using an epoxy putty in conjunction with clear plastic for making windshield replacements. I wish the other forum wasn't closed down so I could of saved the topic on file. But I'm sure these other techniques will work much better.

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There was an article in Scale Auto Enthusiast magazine back in 1986 or '87 that had a very brief mention of using 2-part epoxy to stiffen a foil impression of an emblem. This article was reprinted in Kalmbach's Building and Detailing Scale Model Muscle Cars by George S. Bojaciuk in 1998. I tried it many, many years ago and it didn't work for me, but I think I was using the wrong kind of epoxy. The emblem was still too flexible after the epoxy cured (or did it ever cure?). If I were to try this method today, I'd use a toaster oven to heat the epoxy-filled foil emblem because with that small mass it'll take forever to cure.

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There was an article in Scale Auto Enthusiast magazine back in 1986 or '87 that had a very brief mention of using 2-part epoxy to stiffen a foil impression of an emblem. This article was reprinted in Kalmbach's Building and Detailing Scale Model Muscle Cars by George S. Bojaciuk in 1998. I tried it many, many years ago and it didn't work for me, but I think I was using the wrong kind of epoxy. The emblem was still too flexible after the epoxy cured (or did it ever cure?). If I were to try this method today, I'd use a toaster oven to heat the epoxy-filled foil emblem because with that small mass it'll take forever to cure.

If you mix the epoxy correctly (half resin, half hardener), the amount mixed is irrelevant. Epoxy will cure no matter how large or small the total amount as long as the 50/50 ratio is correct. And it doesn't even have to be exactly 50/50, just reasonably close. More resin than harder means a longer cure time, but it'll still set eventually.

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If you mix the epoxy correctly (half resin, half hardener), the amount mixed is irrelevant. Epoxy will cure no matter how large or small the total amount as long as the 50/50 ratio is correct. And it doesn't even have to be exactly 50/50, just reasonably close. More resin than harder means a longer cure time, but it'll still set eventually.

I know that. I was young and I probably either didn't mix the small amount properly or I didn't allow enough time for the small mass to fully cure. The larger the mass, the more heat is created in the reaction, therefore the epoxy cures in a reasonable amount of time. Adding a little heat for small masses will help them cure faster.

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I haven't done it, tho I very much want to. Here is my understanding of the process (someone with more experience please correct me where necessary):

1. BMF the emblem, do not trim it, rather leave like a 1/2" area around it. 2. Make a dam out of modeling clay around the emblem area. 3. Pour epoxy inside the dam and cover the emblem with some extra thickness. 4. After the epoxy has cured, remove it with the BMF from the car. This is the mold. 6. Pour epoxy in the mold and allow to cure. 7. Sand the back of the emblem until you just sand thru the BMF that is not in the cavity of the mold. 8.Take the finished emblem out of the mold, already covered with the remaining BMF. I hope someone who has actually done this will chime in. don't worry about hurting my feelings if i am totally wrong.

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I haven't done it, tho I very much want to. Here is my understanding of the process (someone with more experience please correct me where necessary):

1. BMF the emblem, do not trim it, rather leave like a 1/2" area around it. 2. Make a dam out of modeling clay around the emblem area. 3. Pour epoxy inside the dam and cover the emblem with some extra thickness. 4. After the epoxy has cured, remove it with the BMF from the car. This is the mold. 6. Pour epoxy in the mold and allow to cure. 7. Sand the back of the emblem until you just sand thru the BMF that is not in the cavity of the mold. 8.Take the finished emblem out of the mold, already covered with the remaining BMF. I hope someone who has actually done this will chime in. don't worry about hurting my feelings if i am totally wrong.

I can't comment on that particular method, but the method that was in Scale Auto Enthusiast was much simpler. Take a small piece of common kitchen foil-- the thin kind, not heavy-duty-- and place it over the emblem you want to copy. Using a soft pencil eraser, carefully press the foil over the emblem. This action should leave a finely-detailed impression of the emblem in the foil. Take the foil and flip it over. Mix up some epoxy and fill the depression with epoxy just until it's level. Let the epoxy cure (this could take a while :D), and then carefully trim away the excess foil with a new #11 blade. The epoxy-backed foil emblem is now ready to use on the model.

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I've never tried using the epoxy method, but I use RVT Silicone 2 part putty to do the same thing. It seems more convenient than epoxy. The silicone I use is from Micro Mark and is over 15 years old and still works fine. I just knead the two equal parts together and press it over the logo or door handle, etc.

For things like interior door handles I've even cast them with just melted sprue.

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I have no shame. Here's what Art said about foil casting the other forum, where he's known as Biscuitbuilder (2nd post on this page). It's pretty much what Chief Joseph describes.

http://cs.scaleautomag.com/sca/tips_techniques/f/9/t/64136.aspx?sort=ASC&pi209=1



I have also seen recommendations to use Testors clear glass cement as a filler in the foil.

Edited by sjordan2
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I had a few minutes today so I thought I'd just try the method I described in my earlier post. I first saw this method in Scale Auto Enthusiast magazine in 1986 or thereabouts.

Using plain, thin kitchen foil, I embossed these two emblems from the 1/25 Revell '68 Firebird:

th_JO066282.jpg The arrowhead quarter panel marker light (bigger pic: http://i101.photobucket.com/albums/m72/fireballmodels/JO066282.jpg)

th_JO066284.jpg The "400" emblem from the decklid (http://i101.photobucket.com/albums/m72/fireballmodels/JO066284.jpg)

I used a pencil eraser to press the foil around the raised features and get a good, smooth surface in the foil. I used the foil's shiny side as the outer surface so the final emblems would be chrome-like.

I mixed up some 5-minute epoxy (J-B Kwik) and filled the depressions in the backside of the foil:

th_JO066281.jpg (bigger: http://i101.photobucket.com/albums/m72/fireballmodels/JO066281.jpg)

th_JO066286.jpg (http://i101.photobucket.com/albums/m72/fireballmodels/JO066286.jpg)

I made sure to carefully "screed" the top of the epoxy so it mostly filled the depression and did not leave much excess outside the depression itself. I placed the two pieces of foil in a toaster oven at 150F for about 30 minutes to cure the epoxy. This particular brand of epoxy is great because the dark gray color contrasts with the foil and you can see what you're doing. A clear epoxy might be more difficult to work with. I cut away the excess foil from the edges of the emblems with a fresh #11 blade. To show the emblems actually in use, I tacked them onto a 1/24 '69 GTO body with white glue:

th_JO066287.jpg (http://i101.photobucket.com/albums/m72/fireballmodels/JO066287.jpg)

th_JO066289.jpg (http://i101.photobucket.com/albums/m72/fireballmodels/JO066289.jpg)

A little red paint will make these particular emblems decent replicas of the originals. There are limitations to this method-- it works better on solid shapes like the arrowhead than lettering scripts-- but it's not all that hard and can add a cheap custom touch to a model.

Sorry if this became a "how-to" post in the "q&a" section :)

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did you try removing the emblem from the foil once it was cured?

I seem to recall in the tutorial I read (probly in that other magazine/forum) that the cast item was removed from the foil (or vice versa) then attached to the model, maybe I imagined that.

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did you try removing the emblem from the foil once it was cured?

I seem to recall in the tutorial I read (probly in that other magazine/forum) that the cast item was removed from the foil (or vice versa) then attached to the model, maybe I imagined that.

Not with this method, since the foil "is" the part and the epoxy is just meant to back up the foil and give it strength.

Question for Joseph: How fragile is the foil mold? Did you have any trouble removing it from the car and filling it without damaging it? That certainly looks like an easy way to get the job done.

Quite fragile, since it's just thin foil. It doesn't stick to the surface, so the hardest part might be keeping the foil in place while you press it with the eraser. A couple of strips of tape would be prudent to hold the foil in position during the embossing phase. I used a toothpick to apply the epoxy, so I had to be careful not to press it into the foil and spoil the part. I did both of these parts without any problems, but if I were doing these to use on a model, I'd make a few extras in case I boogered something in the process.

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did you try removing the emblem from the foil once it was cured?

I seem to recall in the tutorial I read (probly in that other magazine/forum) that the cast item was removed from the foil (or vice versa) then attached to the model, maybe I imagined that.

That's what I posted a link to, above. Art made the foil mold, sprayed the inside of the foil with PAM nonstick cooking spray to act as a release medium, poured in Devcon, let everything cure, removed the part and finished as necessary with an X-Acto blade and paint or BMF.

My only question about that process is that PAM doesn't lay down in an even, fine mist - I use it for cooking almost every day and it gets kind of spotty - and I wonder how that may affect the end product.

But finally, someone - Chief Joseph - has come up with an illustrated tutorial of a way to do it. Thanks.

Edited by sjordan2
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If you mix the epoxy correctly (half resin, half hardener), the amount mixed is irrelevant. Epoxy will cure no matter how large or small the total amount as long as the 50/50 ratio is correct. And it doesn't even have to be exactly 50/50, just reasonably close. More resin than harder means a longer cure time, but it'll still set eventually.

I need to add several caveats to this, in the interest of making complete information available. My 28 years closely involved with aviation composites has given me some insight into the realities of epoxies.

1) Epoxy cures by an exothermic reaction, meaning that it generates its own heat during the cross-linking of the constituent components. If the ambient temperature is below a material-specific threshold (commonly 60deg. F) the reaction will often fail to initialize. In very small quantities the reaction may also fail to initialize because the tiny amount of heat released bleeds off faster than necessary to sustain the reaction. Insufficient heat during cure will result in a network with incomplete polymerisation, and thus reduced mechanical, chemical and heat resistance.

2) Not all epoxies are 50/50 mixes. In reality, only the bottom of the performance curve epoxies are so. Also, as epoxy performance increases, mixing ratio to achieve complete cure and design-strength becomes critical. We mix the avaition stuff on gram scales, and have to maintain accuracy of 1/2 of one percent. While it's true that the next-to-useless 5-minute stuff is forgiving of variations in mixing ratios, the real stuff isn't, and some modelers may encounter problems if they're led to believe sloppiness in epoxy-mixing is universally acceptable. This goes for polyesters and polyurethanes too, and accounts for why some resin casters produce rubbery junk; the reason is often failure to observe correct mixing ratios (but even so-called experts do it, even in 1:1....why, I don't know).

3) The REASON mixing ratios are critical as you go up the strength scale with epoxy is that specific numbers of molecules of each part of the mixture have to be available to interlock with each other. Significantly too much of one or the other (significant being defined by the design of the particular resin system in question) will lead to incomplete curing , poor adhesion and low strength.

This can be a factor even in the 30 minute epoxy systems commonly used on RC airplanes, which vastly out-perform the 5-minute junk, and are in turn vastly out-performed by the real stuff.

The reinforcements I do of roof pillars and other major body surgery on model cars simply will not work with low-strength and / or incorrectly mixed / cured epoxies.

Edited by Ace-Garageguy
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I haven't done it, tho I very much want to. Here is my understanding of the process (someone with more experience please correct me where necessary):

1. BMF the emblem, do not trim it, rather leave like a 1/2" area around it. 2. Make a dam out of modeling clay around the emblem area. 3. Pour epoxy inside the dam and cover the emblem with some extra thickness. 4. After the epoxy has cured, remove it with the BMF from the car. This is the mold. 6. Pour epoxy in the mold and allow to cure. 7. Sand the back of the emblem until you just sand thru the BMF that is not in the cavity of the mold. 8.Take the finished emblem out of the mold, already covered with the remaining BMF. I hope someone who has actually done this will chime in. don't worry about hurting my feelings if i am totally wrong.

I've used this method with good sucess. However there is one step that I changed. Instead of pouring epoxy in the dam in step three, use white glue. The advantage is this: When you have reached step 8 all you need to do is throw it in some hot water and let the white glue desolve. This solves any problems with braking the part to get it free.

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I have no shame. Here's what Art said about foil casting the other forum, where he's known as Biscuitbuilder (2nd post on this page). It's pretty much what Chief Joseph describes.

http://cs.scaleautomag.com/sca/tips_techniques/f/9/t/64136.aspx?sort=ASC&pi209=1

I have also seen recommendations to use Testors clear glass cement as a filler in the foil.

What I wrote on that forum was a description of the way Juha Airio made foil-cast scripts. It might be wise to point out however, that with many model car bodies, the scripts have been engraved into the tooling pretty much to scale as regards the "height" of the detail (thickness of the script above the body surfaces) which can make any casting of such details a very delicate matter indeed.

In thinking about this factor, I reached back into my "memory bank" to an earlier time: Back in the 70's, I was very deep into replicating Indy cars, and found myself in need of instrument details for race car cockpits. Not wanting to tear up a possibly difficult-to-replace dashboard or instrument panel, I hit on the idea of making my own epoxy resin castings of instruments thus:

I used, for making small molds of instruments, "Silicone II clear sealer" which back then was a GE product, but is now produced by DAP, and is available in just about every hardware/home improvement section of the big box stores, not to mention Home Depot, Lowe's etc. This is the old fashioned air cure silicone rubber sealer used to seal up shower stalls against the rim of a bathtub, and is thick enough to not require any sort of "damming" around the detail you may wish to copy.

To start with, you will need something to act as a :"mold release", as DAP Silicone II does stick readily to styrene. This can be Vaseline petroleum jelly, but it takes only a little bit, wiped on, and then wiped down thoroughly to rid the surface (and the cavities in whatever script or detail you want to copy) so that the Vaseline doesn't have a buildup which would obscure a lot of that detail. Next, squeeze a small drop of the stuff onto the detail, and use a toothpick to ensure that no airbubbles are trapped against the script or emblem. Next, squeeze out a large blob of the stuff on top of that, gently spread it out a bit, but try for say, a 1/8 thick layer over the area where that script or raised detail is, and then let it dry thoroughly--generally about 24 hours. Once cured, you simply peel the cured Silicone II blob off that surface, and you have a mold!

Now, I always smoothed the back side of such molds by shaving any peaks off of the cured silicone rubber, the idea being to get it to lay reasonably flat on the workbench. Next I mixed up some DevCon 5-minute epoxy, spread that onto the mold, and again used a toothpick to make certain that all the details in that mold are filled, and not worrying about how thick the layer of epoxy might be.

After the epoxy has cured, it will still be a bit rubbery (flexible), so I simply would put the castings on an old cookie sheet, and bake them in a tabletop oven, but nowadays, a food dehydrator will do the same thing, at a lower temperature, but of course it will take a bit longer. This hardens the epoxy considerably.

Finally, to thin down such details, I simply used a sheet of 400-grit Wet or Dry sandpaper, laid grit side up on a flat surface (used to use the kitchen countertop, but now use a sample of thick plate glass), with a small puddle of water between the back of the sandpaper and the flat surface, which keeps the sandpaper flat, and prevents it from moving around easily. Next, I put a few drops of water on the grit, and placing the casting detail side up, simply scrubbed it gently in circles on the sandpaper, until I had sanded away the excess material to just the thickness of thin flash as one might see on model kit parts. That flash could then be trimmed away with a brand-new #11 Xacto blade, and the detail will be ready to attach to the model.

Yeah, it is possible to break the epoxy details made this way, but if you break one, just make another one.

Art

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Art, I've heard of this technique, possibly from you long ago. I've only seen one photo of a completed script though. Do you, or does anyone else, have any shots of a finished procuct? It sounds like a fine way to do it, but boy oh boy, so delicate. What do you use to color the final script, and what do you use to attach it to the model so no adhesive shows around the edges?

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