DrV

My Feedback: (2)

Does anyone know if Minwax Polyurethane (clear) is Fuel proof (20% Nitro)?

This stuff is made for furniture but I will be using it on ABS plastic cowl.

Thanks

Mike

Thud_Driver

My Feedback: (1)

If you mean the water based Polycrylic in the blue can and intend to use it for a glow fuel airplane - the answer is NO NO NO NO NO........

Others claim the solvent based Minwax IS....they also claim that it yellows. I haven't used it.

DrV

My Feedback: (2)

No, I mean Minwax POLYURETHANE (clear Gloss)

That's what it says on the black can. It will be sprayed over 2 tone alluminum and yellow.

teleplayr

If this is used to apply fiberglass to a model then painted and topcoated with some kind of clear poly or epoxy, it should be alright then, yes?

-Joe

Thud_Driver

My Feedback: (1)

DrV I believe you are refering to a solvent based product. The blue can Minwax Polycrylic IS polyurethane and comes in clear gloss or satin or flat, but it's water based, not solvent based (reducable with paint thinner).

Others say the solvent based minwax is fuel proof. I don't know, I've not used it, but I can assure you the water based Minwax is not. I can only suggest you try it out on something else first. I usually put a coat of paint on a piece of poster board and clear it with the material in question. Take a day for each to harden then find out - put raw fuel on it and see what it does. The results are usually apparent within minutes or less. Others have said the solvent based poly will yellow. If you can stand that effect on your finish and if it proves to be fuel proof to raw fuel, then go for it.

I have also used the water based poly to put down glass cloth using two diffent brands and also a solvent based laquer sanding sealer product. I have been disappointed with all. The water based stuff is soft and rubbery and left a ton of pinholes, even after 3 coats. The sanding sealer needs to get cured in a manner that doesn't cause it to bubble up in the hot sun. I've gone back to epoxy and polyesther resins which always work, always fill and which get very hard.

My $.02 worth of personal experience.

DrV

My Feedback: (2)

Thud_Driver, Thank you for your input. Well, I'm not sure if I have the solvent or water based product.

The blue can poly that you are referring to, I believe is either the flat or satin. Each finish comes in different color can. The clear gloss comes in a black can. So maybe I do have the water based stuff. I did try it out on a scrap ABS plastic and it does not come off with raw 20% nitro fuel or 70% Isopropyl Alcohol. I found that I had to apply at least 2 or 3 thick coats before it was fuel proof. However, the paint did come off in the areas where the poly coat was very light. In addition the directions suggest complete cure time of 72 hours. I got the above-mentioned results in 20 hours. I'll wait the whole recommended 72 before trying out more tests.

Now, is there anything on the can that tells me this is solvent based or water based? How do I know? What else can I use from the hardware store? As you may or may not know, the Environmental Protection Agency (EPA) has banned LusterKote and 21st Century paint in California. My options are limited.

Thanks

Mike

Dzlstunter

You can determine the base of the product by what the label says to use for cleanup and thinning. If it's water, the product is water-based. Dzl

toyking23

My Feedback: (4)

I used the water base, and it didn't work, it is peeling up on a fiberglass cowl.

DrV

My Feedback: (2)

To clean up, instructions on the can state that "mineral spirits" should be used. Thus, I'm assuming this is the solvent-based poly.

If this is the case then the yellowing effect would not be noticeable on aluminum and yellow paint.

Mike

Thud_Driver

My Feedback: (1)

Minwax has several lines of polyurethane, some solvent based and at least one waterbased. All the lines have gloss, satin and flat clears. The blue can Polycrylic I have is water based Gloss.

I'm led to understand all the brands of solvent based clears for furniture have linseed oil in them which causes the yellowing. Like I said, if you can prove that it's fuelproof and can stand the yellowing then have fun.

k_sonn

My Feedback: (32)

Nelson Hobbies sells a water based clear that comes in gloss or flat. It is nitro fuel and gasoline proof. It will not yellow and sells for $19.95 for a quart. You might want to give it a try.

Vulturetec

I used Minwax Polyurethane Gloss (out of a can, brushed) on a Taube I built. I sheeted the entire front end of the fuselage (from the wing trailing edge forward) with birch veneer, stained, then put about 6 coats of the gloss polyurethane over top of that. The only problems I ever had was some fuel/oil seeping under the gloss coat where I had the breather come out the bottom of the fuse - otherwise it seemed to be perfectly fine for me.

coop02

My Feedback: (4)

Minwax water base polyurethane is NOT fuel proof.

If you want water based poly that IS fuelproof, get Carver-Tripp SUPER Polyurethane. I got mine at an Ace Hardware. Be sure it is the SUPER, the regular is right next to it on the shelf.

George

PJC

I use a marine grade Poly. It is fuel proof. Spray the inside of all my fuseswith a light single coat, and then reapply a thicker coat or two to the fuelish spots wing saddle, control rod exits, etc. It comes in a spray can, a gold can I believe, Diesel, Gas, Nitro, it works. It is used to proof wood transooms on sportfishing boats, ahh so many hobbies so little time...

Thud_Driver

My Feedback: (1)

I've noticed that in order for us to have any chance of getting the right product the first time is that we need the brand and entire name of the product as printed on the can and even then sometimes the color of the label and whether is water based or solvent based. The Carver Tripp and Minwax products are prime examples. On many threads a lot of us just mention a generic product or polyurethane or a brand with the word polyurethane.

I you have something that works, could we please have the exact product name. Hate to waste money on the wrong thing.

Thanks!

dant-RCU

My Feedback: (3)

OK.

After having all the associated problems trying to use MinWax Water borne PolyU I found the answer (at least for me).

Varathane Super Diamond Floor Finish. It is a water based poly-u and dries hard and tough (as hard as epoxy in my estimation). Fuel resistant to at least 15% nitro (that is the most I use). Glasses as well as epoxy (doesn't initially stick the glass as good on compound curves as epoxy but a little dab of "77" spray contact cement fixes that). Sands better and quicker than epoxy. Dries much quicker than epoxy. Easier to fix "oops and mistakes". Accepts paint as well as epoxy. Doesn't yellow if sprayed as a topcoat (I doubt any water based poly-u would but the oil based ones do). I use it to fuel proof bare wood also. It is very thin so it penetrates wood well and gets into all of the hard to reach places.

Biggest drawback might be that the current price I saw at Lowe's was $39.85/gallon. They do make quarts but I have never seen one. I got a gallon a few years back at $25.00 from a person who was in the building trades. I pour off some into a glass pickle jar and use from that and keep the gallon can sealed.

I am told Carver-Tripp also makes a similar product but I do not know either the name nor anything else about it.

My .02 - "your mileage may vary"..

Dan

PJC

Sorry do not remeber the name of the Marine grade stuff
I use. I will take a look and get back to you on it. Have no idea of the paticulars at this point though. To give you an Idea how well it works when I had the stopper blow out in my stick, the light coat did not let the fuel soak in. It is good stuff and I will probably post next week what it is. It is a bit pricey, about 10 bucks for a spray can.