Tooling Dough write up

Well I finally had the opportunity to use some of PolymerProducts epoxy tooling dough. It’s a two-part resin/hardener system with a 1:1 mix ratio. You need a scale to weigh out each part, then once they weigh equal…grab it in your gloved hands and begin kneeding the two parts together. Both parts are white colored, just slightly different shade of white… so mix thouroughly until it is one consistent shade of white ( i mixed mine in my hands for about 20 minutes. The pot life is 2 hours. I’m glad i had thick, tight fitting rubber gloves on because one tear in a glove your hands will feel the chemical burn. I was careful to make sure it didn’t get anywhere but on my hands, the plug, and the cup used for weighing. The mixed dough takes 24hrs to cure rock hard. You do have two hours with which to work it onto the plug surface.
If you do use this spread out some paper or plastic sheeting on a table or bench where your mixing. Little bits will fall from your hands.

I mainly bought this product to test it and see how it does, how hard or easy it is to work with. I’d say on scale of 1 to 10 (1 being the easiest) i’d give this product a rating of 5 for ease of use.

I wished i had more time to level out the dough on the plug surface, but it was late at night and i was feeling the effects of a 10 hour work day. Try it when you’re not tired or feeling lazy because it does require patience when working it.

My finished dough surface is very lumpy. I bet a makita grinder with a 4" sanding wheel would level it out the cured dough if i had the time and energy.

I spread the dough about 1/4" thick. You can press your finger through the dough to see what kind of thickness you have…or use a plastic ruler. This stuff is REALLY sticky, but once it is on the plug it stays put, don’t lay down one big lump on one spot of your plug, instead apply small “patties” of the dough to the surface. Also a word of caution… Make good and sure your surface coat is cured before you use this stuff. I also took another forum users advice and layed down two layers of f/g over my surface coat, let it cure 6 hours before i applied the dough.

http://s210.photobucket.com/albums/bb186/Fastrr_photos/SinfulDragon_CarbonFiber/?action=view&current=epoxy_tooling_doughf4i.jpg

how tough is the dough to knead? what sort of pressure do you need to make it stick to the surface of the mold you are making? does it squish easily?

Good questions…

It kneeds together very easy, it’s super squishy. You do need a B-staged coat before you apply this dough, it needs the extra stickiness from the epoxy coat. Or if you added a couple of layers of fiberglass wait 4-6 hours (with a 24hour curing epoxy) then apply the dough. It does take some pressure to push it down against the plug surface. So if you have a foam plug and only foam… i would not recommend the epoxy dough. Also on flanges, if yours are thin on the plug… I would just reinforce flanges with glass and epoxy only, no dough. My flanges are so thin so i decided to not use the dough on those. I will reinforce the flanges with f/g and epoxy only. Also once i’m done building up my flange reinforcements, I plan on going over the entire mold with two more layers of fiberglass for added durability.

This is going to be one heavy mold once done. I’m guessing it will weigh around 18-20lbs.

good stuff man, keep us posted.

I may have to buy more for the other half of the mold… this was a half gallon kit ( i do believe they give you much more than 1/2 gallon though).

Yeah, once i’m done with this half i’ll post up more.

is the tooling dough used to strengthen the back of a mold?

yep… it is used in place of cloth or mat reinforcements. I’m not sure if this epoxy tooling dough would be compatible with polyester gel coat or not… but maybe someone can test that sometime for us.

Next to metal I think Polyester Tooling Gel Coat is the best mold surface. It’s hard as a rock and can be polished to a miror shine.

I’m forced to use epoxy surface coat instead. Smell/fumes.

This stuff i bought on ebay for around $60-70 delivered. PolymerComposites is the seller’s name.

Poly is good for tooling surface shine but it is more of a pain to work with IMO. I find that it gets a bit brittle with time too.

I’ve come to really like working wiht epoxy.

I just wish i could mix up an epoxy surface coat that cures as hard as tooling polyester gel coat.

I may have to buy some aluminum powder and try some of that in the mix.

I thought of a new idea ( to me) is to smooth out the tooling dough on your plug, try using a walpaper roller…sprinkle some calcium carbonate on the roller so the dough won’t stick to it.

maybe this helps? http://shop.ezentrum.de/4DCGI/ezshop?hid=27&sprachnr=2

they have some very nice fabrics on that website!

Are you post curing? Look at the data sheet and it should specify a certain post cure for increased hardness and strength.

FASTRR
Try this company, I use this stuff with very good results.
They have 3-4 surface coat options.
non filled (very shiny and can buff like polyester), aluminium filled iron filled and carbon filled.
They also have tooling dough and various temp rated epoxies.
I have been using this material for 10 years or so for all the carbon car bodies and car chassis molds I have made.
http://resinservices-reklein.com/contents.htm

Thank you Carbon7…wow nice site and products selection:cool:

I’m wondering if just foam ( like polyurthane foam) wetted out would make a good sandwhich mold… using the 7500 fiberglass cloth and first two coats of epoxy surface coat. I know urethane foam will suck up a lot of resin ( perhaps too much making it cost prohibitive?) but it would be very strong wouldn’t it or no?

It seems i could use a strong core material to build up my mold thickness/strength? TET?

That dough says “foam dough” the stuff i used is heavy. Hmm.

FASTRR,
It says foam but it is the same/similar to what everyone else sells.
It makes light, strong molds and is good for high heat moldings.
I have made entire car bodies from it.

Grid scored Balsa sheet with scrim backing help A LOT to stiffen molds. But put at least 30oz of materials between gelcoat and core.

Thanks guys. I did find the balsa at Fiberlay.com I believe it has a scrim back. Picture attached of what i found.

Thank you Carbon7… good to know i’m on the right track with the tooling dough. About how much do you pay for yours from that company who’s website you showed me? I don’t think I found prices on there. Do they have good $deals$ on other items?

Currently I pay about $7 per 38" wide linear yard for tooling fiberglass cloth in plain weave with shipping.
Tooling dough … one gallon $65. (includes shipping cost).
Epoxy… three gallon kit $145.