Removing varnish

[parnold]

I used lot's of clear silicone around my windows and doors, even though I had used butyl. Can't be too watertight as far as I'm concerned. I sealed the entire bottom of the trailer also, where it sits on the frame, with some very expensive (a gift from one of my vendors) flexible epoxy seam sealer, then I coated that with rubberized undercoating.

I figure if I ever fall off a bridge, I have a boat!

[Juneaudave]

Miriam...I have used acetone on oily woods to prep for epoxy. It's a bit stinky, but works well as a degreaser.

Got to say though...I've never seen varnish come off in sheets like that.

[Miriam C.]

Miriam...I have used acetone on oily woods to prep for epoxy. It's a bit stinky, but works well as a degreaser.

Got to say though...I've never seen varnish come off in sheets like that.

I guess you never used nail polish remover huh.... Boy when the girls get in here doing nails it really smells.

Well the pealing went wonderfully cause my daughter and Granddaughter helped. The 14 year old thinks this is great fun. She helped me sand last year. Gotta love em.

Giving some serious thought to epoxy this time. In the next couple of years this is getting covered. I am not into all this work..

ps---Minwax can kiss my tootsies. All 4 sheets are pealing.

[48Rob]

Miriam,

Did you use the water based Helmsman Spar varnish, and then use the Minwax oil based clear?
If you wiped down the raw wood with mineral spirits, then applied water based spar, and then applied oil based spar that would explain the peeling, as the initial bond to the wood was poor at best, and the top coat of oil based spar was likely not as stretchy as the water based bottom layer, which would have the layers struggling against themselves (moving at different rates).

I try to use the least potent solvents first, then work my way up if needed.

Alcohol, then mineral spirits, then Acetone, then lacquer thinner.
Go much higher though, and the finish may melt into a nasty mess...

When I sand and revarnish, I use mineral spirits to de grease and clean, then use a quick wipedown of Acetone to remove the mineral spirits residue.


Rob

[Miriam C.]

Rob I used Helsman spar varnish and last year used Minwax Clear Shield because the varnish was pealing in a few places like it is now. I am thinking the wood or the stain kept the varnish from sinking in. I do remember the varnish being thicker than I expected. Never varnished anything before.

I do think I will epoxy like I did the top. At least it will keep the water out for another year or two...

I do thank you all for your help. Your the best!

[SandyD]

My new tow is a black metalflake dodge and I am
starting to think about the black bedliner spray and
while its wet hitting it with micro glitter .................

I want to see this ~~ Bob is going to Bedazzle his tear

Miriam,

How's the sanding going? My TD, now SandyD's TD has been getting it's "every two year" sanding and recoating of Helmsman Spar Urethane. I used 220 grit myself back when I did it, sanding more where the finish had checked and less where it was still pretty good. I had a little peeling where I didn't scuff up the surface enough between coatings. I think Sandy was planning on sanding out some of my runs from my last coating job. She is taking very good care of my "baby".

I did do the sand dance this spring as Steve mentions. I took the runs out so sanded with 220 with a finishing sander and no muscle. Spar Urethane. Then by hand I sanded with 320 and added another coat. I had a few "chips" either from adhesion or possibly a rock hit but no peeling at all like you show. I think I would have sat down and cried if that happened.

Took out Steve's runs and added a few of my own in a different spot (dang vertical walls).

Shhhhhhhhhhhhhh Steve still doesn't know what happened on the way to Spring Mill. (peek in album for clue)

[Miriam C.]

Ouch Sandy! Hope no one was hurt....

Bob, I really don't think that will have the same effect as paint. You can always epoxy and spray on a neat finish. Love the PU....

[afreegreek]

220 is way too fine for removing finish. it should only be used after the finish is gone to prep the wood for new finish. if you're going to stain it's too fine for that too and with many woods it too fine period. it can lead to adhesion problems in the future. 150 to 180 is about as fine as you need.. I would use a sharp cabinet scraper to remove the old finish but if I was going to use sandpaper I would start with 80 or 100 depending on how thick the coating is. you have BB plywood and there's a mile of veneer there to get to the layer below.. tough work to get there even with a belt sander so there's no need to worry about sanding through the veneer unless you're a complete clutz and continue to sand once you reach the wood below.. I wouldn't play around spot sanding the bad areas either, strip it all off and start fresh.

[Miriam C.]

Does that mean I caused the adhesion issues. I sanded with 100, and 250 and I think I finished in the 300's. Smooth as a peace of glass....... Oh well I am chemically stripping the finish now. There is still stuff on the wood.

The plywood is only 3/8" so the veneer can't be too thick but I am pretty good with a light hand.....

Thanks again.

[Steve_Cox]

Thread hijack time

Shhhhhhhhhhhhhh Steve still doesn't know what happened on the way to Spring Mill. (peek in album for clue)

I do now!

[afreegreek]

:( Does that mean I caused the adhesion issues. I sanded with 100, and 250 and I think I finished in the 300's. Smooth as a peace of glass....... Oh well I am chemically stripping the finish now. There is still stuff on the wood.

The plywood is only 3/8" so the veneer can't be too thick but I am pretty good with a light hand.....

Thanks again.

sanding that fine may not have cause it but it sure contributed to it.. about the only time you should go finer than 220 is on end grain of hardwood like cherry and maple etc. the other thing is sanding to very fine grit clogs the pores with sand dust. it's very hard to remove because you've packed it in with pressure and heat. just blowing it off with compressed air or brushing it off won't get it very well.. a wood cell is like a grain of rice but hollow. when you saw plane and sand wood you open up pores. now the surface is like a bunch of canoes. if they're clean, there's tons of surface for the finish to adhere to, if you fill them/plug them with dust, all there is for the finish to adhere to is the rim of the canoe. people who sand wood very fine are usually doing it because they are going to use a penetrating finish (danish oil, tung oil etc.) rather than a film finish (varnish, urethane etc.). with those types of finish you don't have the adhesion problems and you can sand to whatever grit you want..

your BB should have 5 or 7 layers of veneer. they are all the same thickness at the start. most other plywood has fewer and thicker core veneers and a very thin face veneer. usually less than i/32 to start. they are then run through a wide belt sander at the factory and are much less than that once you get it. this type of ply is much easier to sand through especially on light coloured face veneers.. you don't need to go all the way through to ruin it. once the veneer gets thin enough you can see the core veneer through it. usually you don't see this until you put some finish on and POW! there it is..

chemical strippers are good but they are dangerous. use all the precautions you can. gloves, goggles, skin protection, all of it. even the enviro-stuff is nasty. I would suggest putting the sludge in old metal paint cans and poking a few tiny holes in the lid to allow any pressure to escape until all the VOC's have evaporated. once it's all dried out it's pretty safe.

there's no easy fix to your problem. in the end it's better to strip and start fresh.. it sucks but that's the way it goes.

[Miriam C.]

Well the good news is the chemicals will raise the nap on the wood and I might get away with starting over. Good thing I intended an old fishing cabin look...

I am just taking my time with it cause next time is FRP or something and that is more work. I just wanna go camping and fishing......

[Miriam C.]

OMG. Donotdothisathome.....

You know that wonderful smelling ORANGE stripper...well it leaves orange stuff on the plywood. If fact even Acetone won't get it off without some serious scrubbing. AND if you don't notice the orange stuff until the next morning....

Did I say I was trying to not hurt myself...... Gonna look like Popeye.... This was just plain dumb...

[Juneaudave]

:? OMG. Donotdothisathome.....

You know that wonderful smelling ORANGE stripper...well it leaves orange stuff on the plywood. If fact even Acetone won't get it off without some serious scrubbing. AND if you don't notice the orange stuff until the next morning....

Did I say I was trying to not hurt myself...... Gonna look like Popeye.... This was just plain dumb...

:DOH2::DOH2:I was going to paint trim today...but now I'm scared!!!

[afreegreek]

:? OMG. Donotdothisathome.....

You know that wonderful smelling ORANGE stripper...well it leaves orange stuff on the plywood. If fact even Acetone won't get it off without some serious scrubbing. AND if you don't notice the orange stuff until the next morning....

Did I say I was trying to not hurt myself...... Gonna look like Popeye.... This was just plain dumb...

you are better off just letting the wood dry after the stripper and sand the discoloured wood away.. try a test spot first to see if it hasn't penetrated too far but likely it is only the first few layers of cells and sanding should remove it.. if you use a thinner like acetone etc it is likely to just carry the stain further in..

chem strippers work well but they are risky. I've been in the trade for 25 or so years and I can count on the fingers of one hand the times we've used strippers. a proper cabinet scraper is the fastest safest way.