doomdart

Thinning Devcon: prefer rubbing or denatured alcohol?

27 posts in this topic

For those that thin Devcon with alcohol, do you prefer rubbing alcohol or denatured alcohol? I know there must be reasons why folks use the denatured type, but honestly don't know what the specific benefits are. Rubbing (isopropyl) alcohol has worked just fine for me, but am curious what all of you have to say.

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Denatured is 100% alcohol whereas Rubbing is usually 91%. Denatured evaporates a whole lot faster, not being "watered-down". Rubbing alcohol will probably slow down final curing; I've added water-base paint to Devcon before and even after several days it wasn't fully cured. It did cure okay though when I put the hair dryer to it for an extended period. You also need to be more careful with denatured, it is more volatile.

Dean

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I try to stay away from stuff "cut" with water. Some of the water content gets high enough that it is a pain to thin the devcon. I have had some that wouldn't mix. I typically use acetone, lower boiling point than all the others mentioned. But then again the only time I really use thinned devcon is to coat molds for foamies or softplastics. For cranks I usually use a is and when I need a more flowing product just have a heat lamp or blow dryer near by.

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rubbing alcohol is 70%. I think you can get some iso alchol that is 91% or something close to that. DNA (denatured alcohol) has meth in it so its not 100% alcohol but very close to it.

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I haven't used rubbing alcohol but have used many other solvents: lacquer thinner, DA, acetone, etc. The main consideration to me is how fast a particular solvent evaporates. We're all lucky that epoxy seems to cure regardless of the stuff we throw into it!

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rubbing alcohol is 70%. I think you can get some iso alchol that is 91% or something close to that. DNA (denatured alcohol) has meth in it so its not 100% alcohol but very close to it.

I guess I have confused the terms. I always considered "rubbing" and "isopropyl" to be the same, but I guess not, huh? So really I've not used rubbing, but had good results with iso.

Dean, when you mention the volatile nature of it, do you have specific things to avoid? Obviously you'd want proper ventilation and never use stuff like this near open flame, but what else?

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Doomdart,

Why are you thinning the devcon?? You really don't need to.

Rod

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My pharmacist (me) says to go to the liquor store and get some everclear or 95% or 180 proof alcohol. It won't give you the headache that the acetone will. If you absorb it in your skin, it will be better for you than the acetone.

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Dean, when you mention the volatile nature of it, do you have specific things to avoid? Obviously you'd want proper ventilation and never use stuff like this near open flame, but what else?

Doomdart,

Methanol is bad stuff, cannot be made non-poisonous; fumes or vapors can accumulate quickly and can also be absorbed through the skin rapidly. Respect as you would any poisonous solvent.

Rod, I use denatured only to sometimes thin 2-ton for better penetration into balsa for sealing particularly thin lures to add strength & stiffness without adding the extra weight of a thicker coat.

I would not thin it for topcoating, though some prefer to do it that way.

For cleaning brushes or wiping baits before painting I use isopropyl just because it is safer.

Dean

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None of the above for me I use M.E.K. exclusively, after 1 day the epoxy is as hard as if I never used it. Although MEK is very toxic and volatile it has worked better than Acetone or Denatured alcohol

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Dean,

I understand that for sealing balsa. I think that it would have negative results for top coating for hardness, but maybe the M.E.K. as blackjack says doesn't hurt it. I know that denatured alcohol effects the hardness of the devcon finish.

Rod

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Rob,

If blackjack says that about M.E.K., then I'm satisfied it is so. I've used it for cleaning and as a gasoline additive, with 2-stroke oil for dragracing purposes (not recently). It is nasty stuff, but if I was going to topcoat with thinned Devcon (I'm not) it is what I'd use to thin it.

Dean

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Thanks for all the replies here, guys. This is kind of what I had in mind. I don't want to go waste money trying each type. I also have virgin lacquer thinner (stinky AND volatile) and regular old paint thinner (is this MEK?). I have not attempted to thin D2T with either yet.

With the isopropyl I have not noticed any significant "softening" of the final cure. Like the others I think it eventually evaporates out during curing.

Doomdart,

Why are you thinning the devcon?? You really don't need to.

Rod

I rarely thin when topcoating. Only if I screw up the first coat and need a thin second coat to cover a blemish or two. Or if I'm working a small pool of D2T and find it is setting up before it hits the lure. I will extend the working time that way. Or if using as a sealer, which is very rare for me.

Also need to thin while making POP molds and using D2T as the sealer.

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I have had good luch with thinning with isopro alcohol. I was afraid of the denatured because of what is would do to the paint. I was able to smear creartex paint with denatured alcohol during a test. I think the thing you need to watch for when you thin is getting bubbles in your final coat. I am just putting on a protective coat over paited plastice baits so if I brush a thin coat I do not have problems.

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Look, I know this thread has died. But now I'm curious if anyone has any comment on thinning Devcon with virgin lacquer thinner or regular paint thinner. Is this a really bad idea? Iso works OK for me, but always looking for the better way. Are either of these "dangerous" to combine with Devcon? I'm not worried too much about the flammable nature, but more about the chemical properties. I'm curious both about short term and long term considerations.

Maybe I should contact the company that produces the Devcon, but I suspect they will say don't mess with it regardless of whether or not there is a danger.

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Yeah I agree with RJ.. But I am still the rookie..Why are you thinning it.. am I missing out on something to save me time in the future.. Has anyone ever tried to thin it so much you could just dip the lures.. would be cool if that was possible.. then I would see the advantage of thinning it..

The_Rookie

Blank You.. jo boo.. if you cant hit curve ball I do it myself!! :pissed::pissed::pissed:

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Hey Rookie thats exactly what I do to seal my baits, I cut it way back depending on the type of wood more so than any other reason, hard wood like white oak or Maple I get the stuff to run like water, it soaks in and makes a rock hard surface, I do 2 3 coats sanding between, for Ceder it can be a touch syrupy, I highly recommend it, I only use denatured Alc for cutting, it works great so I'll stay with that, the reason I cut it for coating a lure is most Muskie baits have allot of surface area, some of my big baits the epoxy would be set up before I got it covered, more importantly it makes application allot smoother off the brush, cutting add's a bit more to the window, but not much you still gotta MOVE, lol, hope this helps.

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Muskiefool - I kinda know what you mean with the devcon setting up before you completely cover the lure. I don't make muskie lures but I have been making lures that are over 4". I'm using the 30 min. devcon but after mixing for a few minutes and applying to the lure it starts to set within about 5 minutes! how much denatured alcohol, iso alcohol, etc. is recommended to mix a batch of devcon for a 4" lure?

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About 1 to 1-1/2 teaspoons per package, so I'm guessing about 10-15% roughly, I've done it with more lets say 20-25% and that works too, I would say it's not a perfect science now for me, I was getting very particular with my mixing but I sorta use the Julia Childes method now, LOL, the main thing is to mix the epoxy first incorporating it as fast as possible then add the best Denatured Alc you can find, mixing in a clear glass with a clear plastic spoon so you can see when it's clear of the oil and water look, and remember this is very flammable. Good Luck

John

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Muskiefool -

Q. How much denatured alcohol, iso alcohol, etc. is recommended to mix a batch of devcon for a 4" lure?

A. Envirotex-Lite

:) Dean

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What Dean says is applicable...you may be better served by a different product that you don't have to modify.

While extending working time of epoxy with iso (maybe denatured)regardless of the method of mixing, etc. I feel it is best to add in small amounts, stir, check consistency, add, etc. until it gets what you want. A "small" amount can be as little as a single drop. Depends on how much D2T you have mixed and how much it has hardened.

You can extend actual working time of Devcon close to or maybe beyond the stated time on the package by using iso. I think the working time they claim doesn't apply for our use of the product, but that depends on temperature among other things.

To those who asked why I might thin, I refer back to my original answer.

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