suggestions for finishing veneer (1 Viewer)

[jack x]

Hi guys,

I am in the process of building ACI Sapphire III speakers with 3/4" MDF. The veneer is ordered and on the way.

1) Since I am using veneer, should I still seal the MDF first - and if so, with what?? Can I use diluted titebond or white glue?

2) I have ordered 2-ply veneer. What is the best type (and brand) of adhesive? pros/cons.

3) I already have a gallon of Minwax polyurethane from another project. I think the sheen in "Satin". Is this OK to seal the unfinished veneer? I don't plan to stain the cherry veneer. Will the poly slightly darken the veneer?

Anything else I should consider?

You guys are the best! Thanks!!

 

[Brian Fellmeth]

I would not seal the MDF before veneering. The porosity of the surface will help make a good bond.

For veneer adhesive, avoid water based contact cement. I have used solvent based contact cement, 3M spray adhesive, and iron on wood glue all with good results, except it is important to NOT use any stains/finishes/solvents on the veneer that might weaken the adhesive. Forexample, wet sanding with mineral spirits will weaken the bond formed by solvent based contact cement or 3M spray.

For finishing, I prefer french polishing schellac because I have poor brush skills and lack spray equipment. I don't think poly will darken cherry much, but exposure to sunlight will.

 

[jack x]

Hi Brian, Thanks for your reply. Good point about not sealing the veneer on the veneer side. is there any point to sealing the inside face of each MDF panel before I assemble each carcass?
Can I use gorilla glue - is that poly glue? or would yellow glue be better as opposed to solvent based contact cement?
I don't have spray equipment either.
Whats the deal with French polishing shellac? is that rubbed on/off? Where can I get some.
Does anyone else know if you can get rub on/off polyurethane??
As always - Thanks !!

 

[Pete Mazz]

Pick up some cans of the 3M spray adhesive. Don't use Gorilla glue!!! It would be bad. Spray an even coat on the cabinet and the back of the veneer, being careful not to get any on the face of the veneer.
You can wipe on regular Poly. Thin it down a little with naptha or mineral spirits and apply with a soft lint free rag. Multiple thin coats is the objective. If you use naptha, it will dry pretty quickly.
Pete

 

[Cam S]

what is this Naptha stuff?? can I just pick it up from Revy. Aldo, how much do I put of it into the Poly?

 

[Pete Mazz]

Naptha is benzene, I believe. It's basically used the same as mineral spirits, but less toxic and doesn't slow the drying process. Add about 1:10 of Naptha to the Poly. If you can't find it in a home center, try a paint store.

Pete

 

[Brian J Dupuis]

Jack,
How are the Sapphires coming? I've got all the parts, but am having trouble finding a weekend to begin them . Are they a fun one to work on?

 

[jack x]

Brian,
I started a few weeks ago, but then i got busy with other stuff, so they are currently on hold. Parly also due to the fact that the veneer I bought got wet and ruined during delivery. Secondly because I don't have any audio equipment yet and i have been trying to decide what to buy - receiver - separates, etc. I have been watching the Outlaw 950 situation.
To answer your question, they are not bad, except the shape of the woofer driver is not circular, so they are a bit challenging. I have a few dings with the router that i hope to cover with the veneer. Also, I routed the driver rebates based on the drawings from ACI and not based onthe actual drivers, and I really feel that 1/4 inch is TOO deep for the tweeter. However, it seems OK for the Focal woofer.
Good luck

 

[jack x]

Pete,

Thanks for the insight on the glue and the naptha. benzene is carcinogenic so I think i'll go with mineral spirits. Not that the mineral spirits are not toxic...

 

[MarkDesMarais]

When you say it got wet and ruined during delivery, what do you mean? It may be recoverable. . .

Markd

 

[jack x]

Hi Mark,

The shipping box was not properly sealed, and sat in the rain for almost 2 weeks. After it dried out, it was warped, stained and moldy.

I hope to obtain a replacement soon.

 

[Justin Bowser]

I don't work with wood veneers that much, I always get the hardwood plywood when building cabinetry, but I would think the contact adhesive used with plastic laminates would work pretty good. I use a narrow, short-nap roller with good results then trim the edges with a router.

Apply two coats to each surface if porous, let it tack up, and then place carefully and press down. I got a "J" roller at Home Depot that works well for putting the pressure to it.

The finish I normally use is Deft brand brushing lacquer. It is almost impossible to goof up with it. Lay it on heavy and the brush marks flow out well. After three coats buff with 4-0 steel wool and you have a real nice satin finish. The lacquer dries very fast so it's unlikely it would stay wet long enough to soak through and react with the adhesive. I use quite a bit of iron-on veneer edge banding and have never had any adhesive failure.

 

[MarkDesMarais]

Yeah, that sounds pretty toasted. Warped is usually reversable, but stained and moldy is probably not. Oh well.

Markd