How do you glue intarsia pieces to wood that also needs finish?

[Goat]

Hello all,

I have some projects I cut that need to be glued to a plaque.  These will be trophies for a local club.  The thing is I'm not sure how I should apply the finish since the backer is a visible plaque that also needs finish.  I'm using a water based poly finish.  I've read you shouldn't glue pieces to something with poly applied.  I made some pieces a little over a year ago that I did just that, and they still seem to be holding strong.  However since these will be for someone other than myself I want to be sure the pieces won't easily fall off.  So how to you guys handle this scenario?

 

I was also wondering about gluing the piece to the plaques first, then applying a spray finish.  However I'm afraid the finish will look bad in the lines of the piece.  Wouldn't the finish pool and bridge the "gaps" between pieces?  It also seems like it would be tough to get an even finish on the plaque right next to the piece.  I'd like to try it out, but I really don't want to sand everything down in the event it looks terrible.

Thanks in advance

[JimErn]

I'll be interested in the answers you receive from the intarsia experts we have here, I am just starting in that aspect

I mark the back piece lightly, then tape that area off, it does not have to be exact like a pattern, just fill most of the area with blue tape.  Apply the finish or stain to the backer.  Then remove the tape and glue.

I spray with lacquer, and no it does not pool and fill the joints of the intarsia. 

[tgiro]

What Jim said --

I mark the area where the backing is covered by pieces and tape those areas. I usually make the taped area about 1/8th" smaller than the covering piece. Then apply your finish to the backing, peel the tapes and glue your pieces wood to wood.

I you have finish pooling on your projects your spraying to thick a coat. Back the sprayer up a bit and do more thinner coats.

[Scrappile]

I have had good luck with glues like Titebond "Thick and Quick".  It, and, there are others will stick pieces together that have finish on them. They are also thick, don't run as easily, and less squeeze out, dry quicker and dry clear.   For added assurance I will "rough" up the two pieces where the glue is going to be, (where possible), just to give a little more bite for the glue.  These pieces are not under stress like a joint in furniture or other applications, so the glue does not have to hold as solid.  I have not had a fail yet, least that I know of.

Edited February 25, 2020 by Scrappile

[spirithorse]

I've never had any trouble gluing the intarsia to the backer with any type of carpenter's glue
even if the backer was finished first but I seldom finish the backer first anyway.
If you glue the intarsia to the backer and then spray LIGHT coats of the finish from
whatever angle is necessary to get all edges you can get a nice looking, even coat.
Just try to avoid the temptation to get the spray can too close to the project to avoid the over-spray
(if you are using a spray can) and two or three light coats will not pool and should provide the
protection and nice finish you desire.

Good luck and God Bless! Spirithorse 

[Goat]

Thanks for the replies.  I'll say that I really don't like this step in the process.  No matter what I always seem to mess it up.  All that hard work for nothing.  Putting on finish it by far the hardest part for me when making these.  I'm kinda to the point where I want to leave them with no finish.

I first tried some water based spray poly (I have allot of aspen in my project so I wanted to keep it looking as white as possible).  I shook the can for 2 minutes and held it 12 inches away as the instructions say.  I did a nice even lite coat.  It just made a mess of things and went on like sand paper.  Long story short I had to rip it apart and sand everything down.

I then tried some oil based spray poly.  Instructions are pretty vague, just re-coat coat within 2 hours.  So no idea what the "right" time was.  I waited 30-45 minutes between coats.  The coats when on even and I thought it turned out OK.  However when I checked on the pieces in the morning it sadly wasn't the case.  While it did go on nice and even, it was filled with thousands of little "clouds".  Kinda like ice crystals on a windshield.  If looking at it head on and in normal indoor lighting it looks perfect.  But the second you see it in sunlight or at an angle it gets ugly.  I have stain on the pieces, but it has been over a week since the stain was applied, felt dry and didn't really even smell anymore.  So I can only guess the clouds weren't related to the stain.

So I'm lost at this point.  Do I have to wait 72 hours to sand all this off again?  Or do you think steel wool would fix it?  Its hard to tell how far down the clouds are.  At first I thought it was orange peel effect, but they are thousands of little clouds.

I hate to say it, but I think I'll just spray it with some shellac as I've had moderate success with that.

[JimErn]

First thing I suggest is get some of those nitril gloves the medical folks wear, the oil on your skin can affect the finish.  Use the gloves when final sanding an finishing.  I asked my Dr for some and he handed me a hand full, they can be worn more than once.

That said I am certainly no expert at finishing, and I have not stayed at the Holiday Inn Express lately, but those finishes are "layer" finishes. one on top of the other, and any defects in the lower layer will show in subsequent layers.  

Lacquer on the other hand, my understanding anyway, each subsequent coat "melts" the bottom coats and mixes to make one slightly thicker coat.  I tried one that said self leveling, and others that did not say that, and I can not find a difference afterwards.

If I am wrong in the descriptions, hope fully someone will point it out and we will both learn something

[spirithorse]

Hi, Goat,
I surmise that the cloudy appearance was due to the temperature when you sprayed them.
A consistent temperature of the can of spray and a warm area for the piece to dry really
makes a huge difference.  I think most of the spray finishes recommend 70 to 80 degrees and
low humidity.

Good luck and God Bless! Spirithorse