First attempt veneering - raw or paper-backed?

[Paul Ebert]

The speakers I'm currently building will be my first attempt at veneering. Somehow I'd gotten the impression that paper-backed veneer would be easier for a novice to apply. But, I'd really like to use birds-eye maple and two sheets of paper-backed birds-eye would be > $600. Then, I noticed that I could buy sufficient raw birds-eye veneer for a few hundred bucks. Now, that is in my price range.

So, is it crazy to attempt raw veneer (without a vacuum press) as a first-timer? The speakers are quite large and have an Avalon style enclosure as you can see here:

http://www.flickr.com/photos/[email protected]/3096942642/

[Todd G.]

Re: First attempt veneering - raw or paper-backed?

I would suggest paper backed, but I would look here http://www.formwood.com/sale_items.php and call them even if you don't see what you want before I bought anywhere else.

[Jed K.]

Re: First attempt veneering - raw or paper-backed?

I'd worry about the veneer cracking, if going without the paper backing. Especially if you are going to use the iron on method on such large panels.

Jed

[greysplash]

Re: First attempt veneering - raw or paper-backed?

gorgeous design! is that of your own doing or did you find plans somewhere??

[randy]

Re: First attempt veneering - raw or paper-backed?

Do not use paper back.Use white wood glue,thin it 10 to 20 % spread a thin layer on both the veneer and the box ,let the glue tack up some,almost dry,apply veneer to the box,do opposite sides of the box at one time (two sides),pre cut some scrap wood that is slightly larger than the side that you are gluing, for both sides,and clamp.After it is dry,place the vereered side of the box on a flat surface that can be cut and trim off excess veneer.This is where it is critical.Use a very sharp razor knife (snap off blade stlye) keep the blade close to the side of the box so that the cut is square to the box, and make several light cuts.They make a rubber type mat used for cutting that is self healing that works really well.Do all sides of the box first, then front and back.Once it is done, use a very fine sand paper to carefully smooth up edges.

[tomzarbo]

Re: First attempt veneering - raw or paper-backed?

Paul, first off, those speakers are absolutely beautiful, even in the raw.
Secondly, I don't have tons of experience with veneer, but any veneer with a backing material will be less prone to cracking if you use the wood glue and iron-on method.

Recently, I veneered a medium sized subwoofer with unbacked Japanese ash veneer. It had very dense areas and also very loose-grained areas. The dense areas were no problem to me, but the looser-grained areas acted more like a soft wood - like pine - and those areas really soaked up the glue, much more than the denser areas.

When the looser-grained areas soaked up more glue, it caused them to "pucker up" like our fingers do when they get wet for a long time. Then, when I ironed the veneer, the puckered up areas of veneer tended to crack from the heat and drying and shrinking process of ironing on the veneer. When a veneer is backed with something, paper, or even another type of wood, it's easier - I think - to use the iron on method and get good results because the veneer is inheritly more stable to changes in temperature and moisture.

That said, I think that maple you are contemplating is fairly stable wood and variations of density are minimal - which should make the iron-on method a little easier and less stressful. Others have used veneer conditioner beforehand and say that it helps in this process, I haven't used it myself, I probably should have, though. Test some scraps after you dibby out enough veneer to cover both cabs and try it before you do the real thing.

Good success finishing those beauties up, I remember seeing previous pics of them, and I really enjoyed seeing them come to life. Not that you need it, but some friendly advice -- don't scrimp now, those speaks deserve the best finish you can afford. Take your time and I'm sure they will come out great.

Please post pics of your progress, I'd love to see them.

TomZ

[Paul Ebert]

Re: First attempt veneering - raw or paper-backed?

Tod - thanks for the link. I'll give them a call.

Jed - yes, I'm worried about cracking too. I thought I'd only use the iron-on method for the smaller sides (facets) and use the cold press method for the large sides, but I'm not sure how much that will help.

Greysplash - well, it's some of both. It's sort of a combination of Jon Marsh's M8ta and Modula NeoD designs with my own variations. You can read about Jon's designs here:

http://www.htguide.com/forum/showthread.php4?t=3430

and here:

http://www.htguide.com/forum/showthread.php4?t=27218

You can read my build thread here:

http://www.htguide.com/forum/showthread.php4?t=31184

Randy - thanks for the method - lots of good ideas. I recall reading that waterbased glues could be a problem with raw veneer (something about it soaking through). I assume you've found that not to be the case.

TomZ - thanks for the compliment (Greysplash, too). Regular maple is quite stable and uniform grained, but birds-eye is not. No doubt it's going to be a challenge and I will certainly have to use softener, if I do go that route. Ongoing progress will be documented at the link above, if you care to follow along.

I think what I'm going to do is buy a sheet of the raw veneer and do some practicing. That way I'll not sink a lot of money into it and, even more importantly, risk wrecking the enclosures (which have been a ton of work, matching their weight :D ).

But first I'll give Formwood a call.

[Jim Holtz]

Re: First attempt veneering - raw or paper-backed?

Hi Paul,

My favorite veneer companies are Oakwood and Tapease. I prefer their veneer over Formwood based on my VERY limited experience with each.

I've pasted in glue on instructions from Oakwood that you might find useful.

Jim

Iron on Veneer / PVA glue method
An alternative to using contact cement when traditional press methods aren’t available is this method using white or yellow PVA glue and a standard household iron. This process will help you achieve a better glue bond and allows for the use of 10 mil paperbacked or raw veneer which can save you money. Follow these steps for best results.

Surface Preparation:
The surface or substrate you are veneering must be clean and flat. MDF, particle board or cabinet grade plywood are all satisfactory substrates. If applying veneer over a hardwood substrate, be sure all finish is removed and repair any gouges or scratches that might telegraph through the new veneer. It is not advisable to veneer over old veneer as the heat and moisture generated in this process may actually cause the old veneer to delaminate.

Glue Application:
You can use either white glue or yellow woodworking glue. It is recommended when you use yellow woodworking glue to thin it with 10% water to allow easier spreading as it can be very thick. With a brush or roller coat the back of the veneer and the substrate with glue. If you are rolling the glue a foam roller applicator works well. In almost all cases you should apply two coats of glue to the substrate because some of the first coatwill soak into the surface. Be very careful not to get any glue on the face of the veneer as this will surely be a problem during the finishing process. Once applied, allow the glue to dry to the touch. The yellow glue will probably dry quicker but as a general rule, wait 20 to 30 minutes. An important thing to remember is to apply even, thin coats of glue. Generally speaking, you want to end up with approximately 6 to 8 mils ( 1 mil = 1/1000”) of glue thickness.

Ironing Veneer to Substrate:
Place the veneer on the substrate and position accordingly. Unlike contact cement which bonds on contact, the veneer can be allowed to make contact with the substrate while positioning. Use a lightweight cotton material between the veneer and the face of the iron. An old bed sheet or cotton t-shirt work well for this purpose. With your iron set on a high heat setting, begin to iron the veneer from the center out using a slow and deliberate pace. The cloth should prevent the hot iron from scorching the face of the veneer. Keep moderate downward pressure on the iron as you move it across the surface. Make sure you have covered every square inch of surface and examine the veneer for any loose spots that may not be bonded. If there are any areas that appear as though they aren’t bonded to the substrate, just go back over them with the iron. Allow this assembly to cool for 2 hours before trimming the veneer to finished size. Allow 24 hours for glue to fully cure before doing any finishing.

Finishing Veneer:
Veneer can be finished just like any hardwood. The first step is proper sanding starting with a medium grit paper followed by a fine grit paper. This can be done with an electric sander if you are confident enough or by hand if you are not. Remove all sanding residue with a brush or tack cloth. From this point you can either stain the wood or finish with a clear finish. For finishing tips consult our website at www.oakwoodveneer.com or call with specific questions at (800) 426-6018.

Oakwood Veneer Company
3642 W. Eleven Mile Rd.
Berkley, MI 48072
(248) 542-9979
Toll Free (800) 426-6018
www.oakwoodveneer.com

[bobbarkto]

Re: First attempt veneering - raw or paper-backed?

If you use raw veneer I'd strongly suggest not using the iron on method or any other method that introduces heat and moisture, most especially with the birdseye maple and on large surfaces.
It is very difficult with well behaved wood, the wild grain of birdseye would be more of a challenge. Add the wide expanse on those cabinets and you are in for one heck of a challenge. I wouldn't risk it myself.

If you cold press, do yourself a huge favor and get some PPR (powdered resin glue) or better yet a resocinol glue like Unibond 800 or Urac 185.

PPR gives you a long open time, lets you get things aligned and gives you time to clamp.
It's less likely to bleed through under clamp pressure. This is a real problem on birdseye maple and other open wood.
Dries hard so the veneer won't creep.
Shelf life is long if unopened. Once opened use it up.

Unibond and Urac won't introduce moisture and this is a definite plus with unbacked veneers, especially on larger surfaces like the sides of your cabinets.
It's less likely to bleed through under clamp pressure. This is a real problem on birdseye maple and other open wood.
Dries hard so the veneer won't creep.
Has a shorter open time than the PPR.
Comes in three shades, light, medium and dark. Get the light for maple unless you plan on a dark dye or stain.
Has a short shelf life so buy it when you need it and expect to waste a good bit.

Both these adhesives need to be clamped solidly for about 6 hours and will see shorter open time and accelerated cure time as temperature increases. You'll need a barrier between the cauls and veneer, waxed paper works good.

Another option is epoxy like West Systems or System3.
Can get greatly extended working time with the slow setting hardener.
You need to add some thickener, wood powders or wood flour are best.
May actually be cheaper than Unibond/Urac since smaller quantities are available.
Requires longer clamp time but less pressure.
Can be tinted any color.

Another option is hammer veneering with hot hide glue.
Thats another story, I'm tired...

Hope this helps.

[mgrabow]

Re: First attempt veneering - raw or paper-backed?

Ask 10 people a question and get 10 different answers... Boil them all together and give it a try.....Your design looks like Avalon speakers. You did a great job.... Save the $600 veneer for when you have done it a dozen times or so.

Raw veneer cracks are 99% controlable with blue painters tape. Tape all the edges and across the grain every couple of inches. It takes practice dealing with the tape as it shrinks fast and curls the veneer... I find staggering the tape helps with that.

a cold press method can be hit or miss with me... I still get bubbles from time to time and wind up needing to use an iron anyway...

[Paul Ebert]

Re: First attempt veneering - raw or paper-backed?

Thanks for all the ideas and pointers. I've decided that I will not go with the raw veneer, despite the cost savings - just too risky. And I think I'll do some practice runs to decide between the iron-on and the cold press method.

It sounds like epoxy might be a good way to go. Would MDF dust be a good thickener? I sure have a lot of that (all over my workshop)! :D