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Minwax Polycrylic

31K views 15 replies 13 participants last post by  BillWhite 
#1 · (Edited by Moderator)
So in between coats the products says to sand lightly with 220 sandpaper… I thought that seems awfully course…. Now, you can see scratches in the finish when in the light…. Anybody else had the experience?

I am reluctant to apply liberally since this stuff runs pretty easily… I am not terrible pleased…

I was just going to use Oil based poly, but this is a knife box and even though the knives will not touch the outside, I thought water based was on th safe side…

Also, if you use the spray can, it sputters once and a while and blows a clump on the work piece

Thoughts?
 
#2 ·
I have used some of these water based products to cut down on the VOCs in the shop. I found brushing it out to be OK if it wasn't important work, but it is very hard to build up a finish unless you spray it because it leaves brush marks and runs very easy. It gun sprays pretty well if you thin it a little and and strain it through a fine funnel filter before putting it in the gun. You have to be careful to not get it too heavy and let it dry some between coats and then spray out more. I've never used it from a spray can but seeing how lumpy it is out of a can, I can't imagine it could work very well for finer work.

For the first sanding between coats, 220 is probably OK, as long as you stay with the grain but I never use new paper to do this, cuts too much. The scratches should fill in as you build up the finish. I use 400 for subsequent sanding between coats as needed. It doesn't sand well with a vibrating sander either. Gums up the paper real fast.

Clean-up is the best part of the process and probably for me the best reason to use it and for a quick finish on a shop or utilitarian project it is nice to have around.
 
#3 ·
Schweib,

Thanks for the reply- I used 400 in between coats, and sprayed with the surface flat… I was ale to get a nice, thick coat on and it looks glassy and consistent….

The issue becomes time as I have 5 sides to finish…. The oil based finished seem to have better ability to spry and not run…..
 
#5 ·
If you use 220, do it very lightly, just to knock down the high spots. Then then finish should fill in the scratches. But you can't go wrong with finer paper, even if it takes a bit more sanding. But make sure it is really dry or that fine paper will gum up fast!
 
#6 ·
If your project is small, you can use an airbrush, if you have one. I've had good luck that way. The manufacturers of both acrylic water base finishes, and nitrocellulose lacquer say not to spray, but as long as you protect yourself from inhaling the stuff, you should be OK. In some cases I wet sand with up to 600 grit, depending on the look I'm after.
 
#8 ·
I use the MW Polycrylic Gloss a lot and have had best results lightly sanding with 320 grit between coats 1-2 and 2-3.

After 3rd coat I use "0000 synthetic steel wool pad and end up with somewhere between gloss and satin finish. On large flat surfaces I use a sanding pad with rubber face with the synthetic steel wool pad to make a uniform pass and with very little pressure.
 
#9 ·
I use Modern Masters water based on lots of stuff. Apply with a good synthetic bristle brush (Sure Line 2" for me). Scuff sand with a sanding pad between coats. 4 or 5 coats for hard use surfaces, less for others. Finishing wax for the final softening to a semigloss or satin sheen.
I quit using the MW stuff a long time ago.
Bill
 
#10 ·
A year ago at this time I was doing an officeful of stuff out of Juniper, and matching the existing satin finish. I used Minwax Polycrilic, the subject here.

Here's what I developed: I let the first coat dry overnight and then sanded it with an oscillating sander, 220x. Seems aggressive, I know, but it gave me a great flat surface with flatness and the subsequent coats went on as described, lightly hand sanded between, using the 2 - 3 hours dry time.

The results were high on the acceptable meter.

Kindly,

Lee
 
#11 ·
I've refinished the same tabletop 4 times because the 600 grit Abranet scratches from the random orbit sander keep coming through. I finally resigned myself to using 800 grit wet sand paper on a block going with the grain end-to-end. I think it is working but it is building very slow which is OK since the thinner coats also dry pretty fast and keep the dust nibs down. If I ever get the top finished out I will post the table on Projects.
 
#12 ·
I'm reading through on the topic and still have a question. I recently used polycrylic to cover my countertop surface. I have put about 4 coats on letting it dry between 2 to 24 hours between coats. I also sanded between each coat. It has been 24 hours since my last application and I am happy with the look…but if I get a drop of water on it and it is there for a couple of minutes it starts to leave a white water mark on the surface. When the area dries the mark will go away. However, it seems as if the surface isn't fully protective because it seems to be weakened when water gets on it. What is going on? Should I be using a different finish? Is this normal?
 
#13 ·
I'm one of the few fans of the product here but then again I violate all the label instuctions. I give it no more than an hour between coats if it is dry to the touch (depends on temp and humidity of course). I use 00 steel wool between coats (vac and wipe of course). And I use foam brushes…let it start setting but keep working it until I start doing more harm than good.

Sorry Minwax but it works for me! And I love your product.

I have found that semi-gloss is the best. Gloss might be your problem. Satin turns out about the same as semi-gloss though with a little more final buffering.
 
#15 ·
Once the water base is fully cured it will be water resistant. And it will be no more or less food safe than the oil based version of poly.

Water base will take time to cure even after the water and solvent evaporate. The molecules of the finish will crosslink over time (like oil base poly) to form a barrier. You probably have to wait for it to fully cure. It can be harder to tell when water base has fully cured because it doesn't stink as much as oil base.
 
#16 ·
Purrmaster hit the key word-CURED.
Dry and cure are two different issues.
The MW spray nozzle sucks big time. Lots of product not atomized well. I've shaken 'till my arm is numb, and still get blobs from the can. That's why I've shied away from the product.
Bill
 
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