Tube Amps / Music Electronics
For current discussions, please visit Music Electronics Forum. New: view Recent Searches.
New: visit Schematic Hell!
The sunn still shines online!

Listen to great tunes streaming live right now!

ampage archive

Vintage threads from the first ten years

Search for:  Mode:  

Minwax Polyshades Thinning

9/4/2003 4:43 PM
swingin.little.guitarman Minwax Polyshades Thinning
Bruce, you are correct. Mineral spirits is the solvent for Minwax Polyshades.  
Minwax specifically recommends NOT thinning the poly for two reasons. 1. The EPA and environmental agencies are trying to reduce the amount of organic solvents in the atmosphere. 2. Most people will not take the time to properly mix the poly and mineral spirits in the correct proportion.  
You CAN use mineral spirits to thin polyeurethane, but the proper proportion is 8 oz of mineral spirits to 1 gal of poly. (16 parts poly to 1 part mineral spirits). Mineral spirits evaporates much more slowly than alcohol or lacquer thinner. Mixing polyeurethane products 50/50 with mineral spirits will increase the drying/curing time from several days to a couple of weeks.  
Here in Florida, the relative humidity usually stays in the 50% to 90% range. Most guitar builders and finishers I know have special rooms set up to keep the relative humidity at under 20% to allow glues and finishes to dry properly.
9/4/2003 6:24 PM
Bruce /Mission Amps

I'm going back to straight tinted lacquer and hot thinner!  
There seems to be too many probelms with everything else and lacquer dries super fast here when sprayed.  
9/4/2003 12:39 PM
Todd HEpler Re: Minwax Polyshades Drying Time
Owen -  
I had similar issues with my tweed project. Splotchy stain and long drying times. Unfortunately, the tweed seems to soak up the stain unevenly, and it did'nt change as it dried. Next time I would seal the tweed with a clear poly, then stain to taste.  
9/4/2003 1:49 PM

heh. been following this thread and your problems, owen, and i dont mean to make light of it, but I kind of like the idea of a non-pristine splotchy stain. provided it doesnt look piebald, just a healthy unevenness. evidently the cab i got from bruce already has a single coat of clear poly, so i'll actually have to *try* to achieve unevenness once i start on it :)  
9/4/2003 3:36 PM
TD Madden

Hmmm. Based on how my cabs from Bruce took the shellac, I don't think they had anything on them as-shipped....they turned out a BIT uneven (particularly around the "seams" on the top), but I think that's a GOOD thing.
9/4/2003 3:47 PM
Tom S

I had good results recently using Bullseye clear shellac, not the amber, on my tweed twin clone. It says on the can it dries with a slight amber tint and that's what I was after. To me, the amber shellac is too dark and brown-even cut 50/50. I was also careful at the seams to try to prevent it from getting too dark  
I also read, I think, that to cut down on the likelihood of the seams soaking up too much to use a diluted clear solution for the first coat so as to seal it for subsequent coats of tint.  
My deluxe clone got really dark at the edge of the tweed but dried down to where it was barely noticeable. I waited a day or two between coats also.  
9/5/2003 2:26 AM

Hey everyone, thanks for all the advice etc. Tom, your amp looks awesome! I think I prefer that to even a tinted look.  
Well, my amp seems to be a lot less splotchy. I think if I let it dry a few more days it will be as good as it is going to get. Then I don't think it will be anything another UNDILUTED coat shouldn't cover! Basically at this point, as diluted as the poly was, it looks like one coat of the honey pine. It looks nice, but I'd like a little more gloss.  
So, hopefully some others will learn from my mistake. Humidity is definitely a determining factor in the result of the staining. At best, I think the whole undertaking is risky.  
On a good note, I fired up my Marsh 5E3 today and it worked perfectly, a bit of hiss, as expected. Looking forward to plugging in tomorrow.
<<First Page<Prev Page 2 of 3 Next> Last Page>>