Oops. Finish Help Needed.

[Paul R.]

Hello all.

I've recently taken to woodworking, specifically home furniture.

Pictured is my second project, which I was feeling pretty good about until I damaged the finish on the top.

 

I followed the advice of many for the finishing process when staining, but when I went to 220 the first coat of poly in preparation for the final coat, the poly scratched up pretty badly. The top became cloudy all over and some of the stain even came off while sanding.

 

Maybe the poly was not fully dry? Too much sand paper pressure? Wrong sanding method (I used my hands - no tools)?

 

Regardless of which mistake I might have made, I'm thinking that I should:

 

1) Tape off the edges up to the top

2) Sand the poly completely off the top

3) Restain the top

4) Poly the top

 

Does this seem like a good solution?

 

Also, I'm afraid to try the whole 220 sand and second coat for the rest of the peice now that I've evperienced this frustration. Would just using one coat of poly be satisfactory for this project? I'm afraid maybe my finishing methods up to this point (120 sand, 220 sand, pre-stain, 2 coats of stain, poly, 220 sand...) may have made the final step in the process bound to fail.

 

Thanks for reading,

Paul

[AceHoleInOne]

I think you have figured out by now, you have committed the biggest finishing sin  Sand through!

 

You are best off to remover the poly with the color and start over. 

 

First off...do not sand your poly until you have enough finish built up, to sand. You need at least a few coats down before you sand. If you must sand a first coat or a second, use 600 paper and a very  light wipe to knock down nibs and whatever.  220 is too coarse of a paper to sand poly in my opinion. I like 320 foam backed paper and go easy and stay off the edges.

 

I would do at least 3 coats of poly. Remember when you are sanding back a finish you are removing a coat of finish. So you need to add back with another coat. 

 

-Ace- 

[Brendon_t]

Wow those are some deep scratches.

When I use poly, I don't go back to 220.after a few coats, I give it a LIGHT sanding on a shop made cork backed sanding block with 320 or 400.

My advice would be to grab a piece of the same wood scrap and go through any adjusted method on there first to work out the process

[Paul R.]

Thanks, Ace, Brendon.

So the poly was too thin and the paper too coarse. The Minwax site says 220, but I see that's just too coarse.

I have set aside a piece of scrap to work out the process on. I will begin that tomorrow.

 

Ace, when you say you would do 3 coats, do you mean you would lay down the first coat thick enough to sand, sand it lightly, and repeat the process two more times?

 

Thanks

[keith.d.mullins]

Agree that the best course of action is to remove what's remaining and work with a sample piece.  I'm just a beginner so take my advise with a grain of salt, but I have had great luck with using wipe on poly for the first 3 coats or so, using 0000 steel wool or 800 or higher sandpaper between each.  Then I apply a brush on poly, sanding after it cures well, usually 24hrs for me.  I very lightly smooth it with the 800 or 0000.  Always using gloss to this point.  Once I have it where I want it, I finish with a wipe on poly of chosen sheen or my favorite is to wax with paste wax.  The paste wax may not be a good choice for a table top, depending on how it will be used.

[Paul R.]

Thanks, Keith.

I'm definately gonna do the sample piece one step ahead of the table. As I sould have done and will do from now on.

So why do use 3 coats of wipe on and then a brush and another wipe on? Is that just a method that you have found comfort with? Seems like a LOT of poly. Are you making very high glass stuff?

 

I have heard to use polishing compound, so may give that a go when the time comes.

 

Thanks

[AceHoleInOne]

Typically it takes 3 coats for most woods. Woods that are thirsty or very porous can take up to 5 coats. because the first 2 are pulled deep into the wood and not building up onto the surface.

 

Did you thin the poly? If so...it will take you even more coats to get a 3 coat build if used straight from the can.

 

-Ace- 

[wtnhighlander]

Thjs is why I like shellac. Five coats on my coffee table in under 3 hours. Bam!

Finish for the impatient.

[Paul R.]

I'm definitely impatient. I'm going to start the repair process tomorrow. I'll post pics of my great success.

[Boatworks Today]

Quick tip for sanding between coats of poly; use a superfine (grey) scotchbright pad and gently wipe with a tack rag just before application..  This is roughly the equivalent to a 600-800 grit paper but it doesn't really remove material (just abrades it for adhesion).  I use this for the first few coats (3-4) then you can go over with traditional paper to knock down bumps, level, remove dust, etc.  Probably use 600 wet / dry for this.  Then 2 more coats using the SB pad between and you should have a decent film thickness.  Let this cure for a week before it see's any hard use.  Foam brush for application as it's a very thin material ..  Good luck!

[keith.d.mullins]

Thanks, Keith.

I'm definately gonna do the sample piece one step ahead of the table. As I sould have done and will do from now on.

So why do use 3 coats of wipe on and then a brush and another wipe on? Is that just a method that you have found comfort with? Seems like a LOT of poly. Are you making very high glass stuff?

 

I have heard to use polishing compound, so may give that a go when the time comes.

 

Thanks

It's really just what I found works for me.  I like the first coats of wipe-on just to get that just get everything sealed up without have as much risk for runs, dust nibs, etc.  After I get the initial layer (really multiple layers), I will brush on a thicker coat depending on the planned use.  I would like to build the entire finish with wipe-on but I'm not that patient.  Yes, I use this mostly for a glass finish.  I looks great but leaves finger prints.  I wouldn't want it for a table top.  I would probably add a satin  layer on top.  All I have experience with is Poly so I can't comment on the others, but the poly would certainly hold up on a table top.

 

Good Luck,