Help! Rough surface after poly coat!

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What's going on!?!? I'm using a varnish brush to apply satin poly (Minwax) to maple, and my surfaces are rough to the touch!
I've eliminated almost all of the dust in the room, as this has happened before & I thought that dust was the cause. It could even be miniscule air bubbles in the coating, but how do I prevent it!!!?!
Help!!!!
DK
"If you can't beat them, arrange to have them beaten." ---George Carlin
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If I had a dollar for every person who has complained about Minwax products on this NG, I'd could buy a pad next to Bill Gates. If you are going to use that stuff, folks here have suggested thinning it down a bit. Others have thinned it and put on umpteen coats with a rag. Fun, huh? That's why I'm in the market for an HVLP...
dave
DK wrote:

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I probably should buy a HVLP, but my Fitz& Fitz trim gun (aka: Door-Jam gun) works so well, I'd have a hard time justifying anything else. It does make a healthy cloud of spray that will permanently weld your nostrils shut if not wearing a respirator, but sure puts on a smooth finish. I bought this back when I painted cars (hobby).
Post your results if you get one.
FWIW, I've used Minwax products for over a decade. Always had to thin the poly due to the high temps in my garage workshop (typ 90-95 degrees). I built a project at work last month in our air conditioned shop (76 degrees). I used no thinner, and the poly flowed out beautifully on red oak only using a foam brush. I put on a few coats, smooth as a baby's rear. Too bad it isn't that easy at home.
Robert

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Robert, I've used a foam brush a few time with their poly and still got the bubbles. It was non-critical work--baseboards, but just as bad as the bubbles were the bits of foam coming off the brushes. Maybe there are better foam brushes out there than the ones I got.
I sprayed latex with a HP gun one time in my garage onto a night stand. That left the most hellacious mess imaginable. Paint dust was everywhere. Even inside tool box drawers. I learned my lesson. I'm intending on spraying precat laq outside, away from sources of ignition with an HVLP.
dave
2manytoyz wrote:

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Well, I already have one coat on, but am willing to make the switch. I'm pretty desperate. What would you recommend that would stick to the existing poly?
Thanks DK
wrote:

"If you can't beat them, arrange to have them beaten." ---George Carlin
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can you sand it smooth when it's dry enough (careful not to sand thru to the stain if there is anything) and thin the next coat?
dave
DK wrote:

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scotchbrite pads, or 0000 steel wool. -- Jim in NC
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Thin your poly a little so bubbles can escape. Sand lightly with 220 between coats.
Robert

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Thin with what? (Okay, the obvious answer is lacquer thinner, but sometimes the obvious answer isn't right.)
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Eek! Mineral Spirits. Add a lot less than you think you'll need, try it on some scrap. Still doesn't flow quite right, add a little more. I've sprayed quite a bit of automotive paint, so I can quickly judge the mix by watching it drip off the stir stick. Like asking a cook how much salt do you add.
The amount needed will also depend on your shop conditions. It's so hot in my shop this time of year that the poly quickly dries. I can sand and apply several coats in a single afternoon. I apply multiple light coats rather than one or two heavy ones. Less sag, drips, and soft spots.

sometimes
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Rule of thumb for thinning. Whatever the containers lists for clean up can be used for thinning.
--
Mike G.
Heirloom Woods
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Soap and water?
-Jack
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First coat is always rough. The unsealed wood soaks up some of the poly unevenly. Sand it and add another coat and things will even out.
As for air bubbles and dust. They are almost impossible to eliminate entirely when brushing. Myself, I prefer to thin the first coat 50% to seal the wood then around 15 % for the rest of the coats. I also prefer, with the thinned poly to wipe it on with a lint free rag. It eliminates a lot of the things that are problematic with brushing, air bubbles, runs, sags, etc.
It does mean you have to add a few more coats to get the same build but in the long run I find it saves times.
--
Mike G.
Heirloom Woods
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DK wrote:

First coat? Of course...always need to sand after the first coat.
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Chris Merrill
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Honestly, it's all in preperation and execution. I have HVLP, and it's a PITA to use & clean on small projects. I like a nice $20 brush - china bristle I believe it's called.
Once the surface is smooth from sanding, you can begin (at least to 220)
First thin the junk a little bit. 10-50%
Then soak I mean soak your brush in the thinner. Dip 1/3 of the bristles in poly. Start 6-10 from where you would start at the edge, go to the other edge, then come back and get the beginning. Use a 45% angle, then apply pressure down at the end. Standard - how to apply poly stuff. If you do more than 5 or so square feet, resoak in thinner.
Re dip in poly, and do the rest.
I like you, had bubbles, dust, all kinds of nasty stuff. I bought an HVLP, compressor, the works. Not worth it (well compressor was). Read a book, that's what they are there for.
My instructions above are incomplete, but they might help. I did terrible finish work till I got this book: ISBN 1-56158-299-9 (no affiliation)
Look it up, get it at a local book store. Or any other book for that matter. Some other poster here said this to me (prolly not the same book) and I blew it off. Why a book? I have high speed internet. Hehe. 2 months later I got a book, and now I have a piano bench I can shave with (used as a mirror, not a razor).
Charles
PS: Hobbiest, never made a penny from this, but I sure like the end results. And I gave up with poly and now use Shellac (the premixed gunk) it's easier for me, smells like a screwdriver (the drink), and dries pretty fast. Poly works good as above, but it's a pain to clean up. I like using the denatured alcohol, as it's already in my system, why mix things up?
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I make quite a few "trophy" projects for folks at work (shadow boxes, flag boxes, etc.) Have used minwax wiping poly for several years, and I love it. It is really just thinned poly, which is what most folks are recommending to you. However, I have discovered a finishing trick that is really cool. I was browsing at Woodcraft, and came across these foam polishing pads that fit my hook & loop random orbit hand sander. I usually apply two to three coats of poly, with a very light sanding with 400 grit sandpaper or 0000 steel wool on the hard to reach places between coats. I really spend as little time doing this a possible. I then use regular liquid automotive wax with the polishing pad for just a couple of minutes. It slings the wax all over the place if you are not careful, and will sling some even if you are very careful, but the finish is as fine a rubbed finish as you will find anywhere.
Bill
DK wrote:

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OK, I've read most of the messages, and their 'patented bitching' about MinWax products.
High cost spray equipment is nice a) if you can afford it . . . and the compressor to supply air, and b) if you have the space to use/store it. NEITHER of these things answers YOUR problem NOW.
I have had good results using MinWax products . . . I'm not 'dedicated' to any one particular brand, by any means. It goes along with the 'KISS' principle . . . what works and gives you the results YOU want in the least complicated way.
Are you using Oil or Water based Poly? What was your 'prep' schedule? What were the conditions Before and After you applied the Poly? Where did you do the application?
A few years ago I built a kitchen storage cabinet for Joanne. While it was Pine, I made the top & rear trim from Maple. I used water-based poly and it's STILL 'like glass'. She uses the top like a 'side table' with a lamp, a couple of cups, and what ever she drops on it to look at / sort through during dinner. I haven't touched it since I built it.
Prep - Sanded with 80 grit, just 'broke' the edges. Vacuumed off the dust, and out of the pores Filled the pores with Bartley's 'Natural' colored filler. Sanded smooth with 80 grit to remove any filler on the surface Vacuumed Stained lightly {MinWax Gel Stain} to get close to the tones of the walls, cabinets, and table 'Deglossed' with a 3-M pad Vacuumed
Poly Application - IN THE BASEMENT - relatively constant, cool temperature {because this is a mostly 'uninhabited' part of the house, I keep the heating/cooling ducts closed and taped} With a 'decent' foam brush, applied the first coat of the poly. Lightly flowed it on, tipped it off, and LEFT When dry, the next day, 'scuff sanded' with 220 grit, & applied 2nd coat of poly {DITTO . . . 3rd coat {Ditto . . . . 320 grit 4th coat {Ditto . . . . 400 grit 5th coat {Ditto . . . 600 grit 6th coat When this was dry, the next day, I gave it a good rub down with a FINE 3-M pad, followed by a 'rub-out' with some automotive compound, and finally 2 applications of well rubbed-out, hard, automotive wax. The 'application time' was probably 30 minutes per 'step', more in 'getting ready' & 'cleaning up' than the actual 'doing'. The rest of the time was simply waiting.
Other than the final 'rub-out' steps, this is how I apply varnish to a Mahogany transom or trim.
The ambient conditions, or time of day is IMPORTANT. What you think of as bubble IN the poly, may actually be bubbles coming THROUGH the poly. In it's simplest explanation, it's 'outgassing' from the wood as the temperature increases. One reason for having a constant, cool environment, or doing the application late in the afternoon - as the temperature is dropping from the heat of the day. Also, by filling the pores, you eliminate almost all of the places where the 'gas' comes from.
You may have 'eliminated' all of the dust, but did you? How soon after did you start the application? What small 'dust' particles {for instance, smoke} are still in the air? Air conditioning/heating on? Ducts open, etc.
The amount of 'sticky' time is dependent on the material. One of the reasons I like water-based poly is that it dries quickly. When I was re-finishing some interior doors, I basically used the same schedule; except I was able to apply a coat every 4-6 hours. In the case of the Maple top . . . I chose to wait 24-hours. Varnish, or oil-based poly dries much more slowly, so remains 'sensitive' for a longer period.
Long winded, but that's my point. 'Instant Gratification' with an 'Instant Finish' . . . spray the hell out of it, and spend your time on the 'learning curve' and the clean up. KISS principle . . . you get OUT of it what you put INTO it. Plus, I really think it's quicker !!
MinWax vs 'high-priced spread' ? Can't really say. I'm cheap. I use stuff that is from decent companies, with a decent reputations, with Laboratory Technicians that can answer SPECIFIC questions. There is at least one MinWax stain that I WON'T use . . . and I can't get a straight answer as to why the color is completely DIFFERENT than either the 'printed' chart or the ACTUAL finished 'samples'.
For what it's worth . . .
Regards & Good Luck, Ron Magen Backyard Boatshop

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Any slow drying film finish is subject to dust capture and bubbles unless you put down an extremely thin layer. It is not a function of brand. Polyurethane fits this category. Put down as per the directions on the can and you will have a medium thick slow drying film. Dust settles into the finish before it has a chance to dry. If the finish is too thick, it will not enable trapped bubbles to pop and it will not have a chance to level before it starts to cure. One solution is to thin the poly with 15-25% mineral spirits. You can put it down with anything at this dilution except a rag. I usually use a foam brush and scrub it into the wood to the point where a foam has been produced. I then tip it off to remove all the foam and any other bubbles. You can thin it more and use a rag which puts down a very thin film. You will have to lightly sand each dried coat to remove any dust nibs or bubbles that may remain but the initial result is much better than using the finish full strength with no tipping off. Another solution is to spray but it is not worth it with poly. You are better off using lacquers or conversion varnishes. You might also consider a water borne polyurethane. These dry very quickly. To a very small extent, these can be thinned with water but it is best to use one of the cellosolves to keep from tampering too much with the formulation.
Good Luck.

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If you read the directions you wouldn't have problems. Almost always rub down a coat of poly. Use either 220 (or 320) paper or 0000 steel wool. Poly has a tendency to bubble attract dust, etc. Rubbing down is a good idea. Part 2 of this is that every coat left longer than a certain period (like 8 hrs.) needs scratches for the next coat to adhere to since poly application is not based on solvents softening the layer underneath. This property is what makes people love it for its durability and hate it for its looks.
--
Young Carpenter

"Violin playing and Woodworking are similar, it takes plenty of money,
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because of sanding fuzz. You need to raise the grain and remove the fuzz. dampen the wood to make the gain raise and sand it real lightly at about 22 to remove the fuzz. or just sand the first coat. now if you planed or scraped the wood you would not have the problem.
--
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