During or after?

[Anonymous]

Hi all

Well, after years of applying finish only after the project is completed I have decided to try finishing before final assembly on my latest project.

So, how do members stop the finish covering glue surfaces? tape? other method? Seems like a lot of effort applying tape.

Also, do many people finish before final assembly and why?

 

[devonwoody]

How about making the joint oversized and then after finish has been applied take the joint down to size and that would then be virgin timber :x

 

[Evergreen]

Hi Tony

Yes, according to what I've read, you're suppposed to put masking tape in the dados or on the exposed joint surfaces. But the only advantages that I can see of applying the finish after gluing are that it improves access to awkward areas and it avoids any risk of contaminating the surface with excess glue pre-finishing. But then - won't cleaning up excess glue afterwards from your nice new finish also spoil it, I ask myself?

I only ever use oil or, sometimes, a matt acrylic varnish and I've never had problems getting it into tight corners.

Regards.

 

[Evergreen]

Sorry - just read my last post. The second line should read

"But the only advantages that I can see of applying the glue after finishing are ...."

Got a bit muddled there.

Regards.

 

[Gill]

Hi Tony

I've heard that severing the wood fibres with a sharp knife stops finish from bleeding into wood that you don't want to be treated, but I've never tried it myself.

Gill

 

[SketchUp Guru]

I think one benefit of prefinishing would be in the production of paneled doors or case sides. If you prefinish the panel, you don't need to worry about an unfinished area showing when the panel shrinks. You also don't have to worry about the panel being 'glued' in place by the finish.

 

[Chris Knight]

Tony,

It depends on the piece I am building but I generally pre-finish parts that will be difficult to finish later or where I would find it difficult to remove glue squeeze-out. I use green 3M masking tape (the stickiest sort- designed to be "lacquer-proof" - just make sure to get it off as soon as possible because it sticks harder, the longer you leave it) to protect parts that must later accept glue.

Sometimes, this pre-finishing is little more than a protective coat of finish which will prevent glue getting into the wood where I don't want it and as such - depending on the final finish to be used be shellac or wax. Sometimes, I want to go the whole hog with grain filling, staining. finishing and polishing.

If doing the "whole hog" be careful that any surface preparation involved doesn't for example, inadvertently reduce the thickness of a jointing surface otherwise unexpected gaps can be created. Masking the jointing areas up at the start helps one to avoid this.

 

[Anonymous]

Thanks all, interesting. Must admit that I did expect more reponses to this one but I guess most simply do as I did and apply finish after the glue up?

Philly, I thought you applied finish before glue-up on some projects?

 

[Philly]

Tony
Sorry, meant to reply earlier
I'm a fan of pre-finishing. Oil, shellac-piece of cake! I sometimes use masking tape to cover joints, etc, but usually just be careful when applying the finish.
To me, the big advantage of pre-finishing is not problems with glue squeeze-out. You can remove it easily and you don't have to worry about blotches where the glue has touched the timber. Also when you clamp the piece up you really are FINISHED with a project-just a wax if you feel like it.
I've not encountered any problems with working this way. You also never get a build-up of finish in those tricky corners.
Hope this helps
Philly

 

[tim]

Tony,

I'm with Philly on this. The advantage for me is speed esp for inside carcases - I can lay the panels flat on the bench and spray, pad or roll on a finish without having to do any internal corners or twist into awkward positions.

Cheers

Tim

 

[Anonymous]

Tim - roller, now that I like!!! Danish oil with a roller on panels? Buying a small roller is now on the tuit list, thanks for that

Philly, I was a bit worried about using Shellac as prefinish and bottled out and applied Danish oil in the end. I mixed some blonde de-waxed up ready but thought it might be more prone to marking during assembly

 

[Philly]

Tony
Shellac goes off REAL quick, as I'm sure you know. If you should scuff the surface of the finish when clamping up a quick wipe over with your rubber will re-melt the surface, leaving it fresh and new.
Just give it a go, you'll be hooked!
Philly

 

[tim]

Tony,

I use these:

http://www.screwfix.com/app/sfd/cat/pro.jsp?cId=102099&ts=83765&id=17048

they are small enough to keep 'wet' in a small, lidded jar which keeps mess down.

Cheers

Tim

 

[Bean]

Hey Ho
I just spotted your post, I always finish the insides of projects before glueing up, not sure why it just seemed sensible, as someone said earlier it aviods build up in corners and the occasional bare patch.

Bean

 

[devonwoody]

I DON'T DO FINISH INSIDE (drawers or boxes anyway).

Does anybody else?

 

[DaveL]

I DON'T DO FINISH INSIDE (drawers or boxes anyway).

Does anybody else?

I always finish both inside and outside. If you leave the inside unfinished there is always the chance of the timber taking on or losing water through those surfaces which can make things move and twist. I don't work the finish up on the inside of cabinets to the same degree as outside but all of the surfaces should be treated.

Do you paint the top and bottom of a door? I do. :roll:

 

[devonwoody]

So if you don't work a high finish insides, why bother putting a finish before glueing up?

 

[Philly]

I try and use only shellac on the insides of a project-it doesn't smell when dry (unlike most other finishes :x ). If you've ever finished the inside of a drawer or box with oil I'm sure you know what I'm talking about..... :lol:
Philly

 

[Bean]

Ahh but the more aromatic oils like Organoil (he he) smell great so they can add to a finish on the inside of a box, but I would not use them on a drawer :lol:

Bean

 

[Philly]

True, Bean! I have used Chestnuts lemon oil inside a few boxes. Yumm!
Philly