Veneering Technique Question

[JimK]

I need some advice on veneering. (yes, I have read many of the existing threads). Lets say you have a large CC channel box in MDF that you plan to cover with unbacked veneer using the TB II iron-on technique......because that is exactly what I am planning.

When you start to apply the veneer sheets, is it preferable to start with the least visible side first, ie the bottom, and then trim the veneer to size? It would seem that doing this would allow each successive sheet of veneer to cover the edges of the less important sides. Moving from bottom to back to sides to front to top, would result in the top and front sheets "capping" the edges of the other sheets, and leave a more appealing boundary. Is this logic correct?

I was also planning to use contiguous sections of veneer to cover the left side, top side, and right side, so that I could have continuity of grain across the edge boundaries. To do this well I would need to pre-cut the sheets with very little overhang for trimming. Is this a good idea, or more trouble than it is worth for a non-expert?

[Bill Schneider]

Applying the sheets in a sequence that hides joints is common. I'd do it.

Same for the continuous grain question.

However I wouldn't use iron-on for unbacked veneer though. You'll likely encounter splitting from the heat.

[cjd]

However I wouldn't use iron-on for unbacked veneer though. You'll likely encounter splitting from the heat.

Just want to reiterate this.

It can be done, but takes lots of care - a veneer softener, and probably a slightly more application-specific glue like Heat-Lock. Depending on the species it may not be worth trying though - no matter what you do they'll split.

[JonMarsh]

Just want to reiterate this.

It can be done, but takes lots of care - a veneer softener, and probably a slightly more application-specific glue like Heat-Lock. Depending on the species it may not be worth trying though - no matter what you do they'll split.

+1 on this. If you're serious about going that way, do a test sample of similar size to one of your cabinet surfaces- will give you some idea how feasible it is.

[CADman_ks]

I need some advice on veneering. (yes, I have read many of the existing threads). Lets say you have a large CC channel box in MDF that you plan to cover with unbacked veneer using the TB II iron-on technique......because that is exactly what I am planning.

When you start to apply the veneer sheets, is it preferable to start with the least visible side first, ie the bottom, and then trim the veneer to size? It would seem that doing this would allow each successive sheet of veneer to cover the edges of the less important sides. Moving from bottom to back to sides to front to top, would result in the top and front sheets "capping" the edges of the other sheets, and leave a more appealing boundary. Is this logic correct?

I was also planning to use contiguous sections of veneer to cover the left side, top side, and right side, so that I could have continuity of grain across the edge boundaries. To do this well I would need to pre-cut the sheets with very little overhang for trimming. Is this a good idea, or more trouble than it is worth for a non-expert?

+1 on the hide the joints thing. Just plan it out so that they are the most hidden.

I did the same thing when I veneered to make it look like a contiguous piece. That's not reallly that hard to do, BUT it also takes some planning to plan that out so that you don't cut one too short.

One thing that I haven't seen mentioned yet is that I would definitely recommend making sure that you have ALL of your MDF joints covered with something like bondo so that they don't show up. I think that the best way (although, I've never done this) is to do double veneer.

My joints haven't cracked, YET, but they are visible, or maybe I should say, at least to me. See the thread on woodworking tips about, "letting it go". Sometimes, you just have to do your best, and let the rest go...

[JimK]

OK, I may have a change of plans here. I ordered the Pau Ferro (south american rosewood) from Macbeath, and assumed that it was unbacked because the web site did not say that it was. I had taken a quick peek at it when it was rolled up, and saw the back side that looked very similar to the main color of the wood.

Now that I have unrolled the sheet, I notice that I cannot see any grain on the back side, and it has what looks like a very fine woven texture on the surface. Is this paper backing? I had thought that it would be more obviously distinct from the wood, based on some paper backed veneers that I had seen pictures of.

If this is paper (or some other backing) do I stick with the TB II plan, or go to a non-water based adhesive like urea or urethane? I am covering a fairly large CC cabinet: the top side is 32"x14".

Thanks for all the suggestions so far, this is a great forum!

One more thing, the front side of the veneer is gorgeous!

[PMazz]

Sounds like fleece backed. I've never heard of full or half sheets using it tho. From the website, it shows 2 x 8' sized pieces, so I'd assume it had some sort of backer on it. Try a small piece on some scrap and try to pull it up. Should be fine I'm guessing.

[cjd]

If you want to take as few chances as possible but still do iron-on, use Heat-Lock. You can get it at veneersupplies.com at the least. In theory, PVA has creep issues. In practice, it seems to work better than theory suggests for speaker projects.

C

[Hdale85]

I love Heat-Lock, it's not that much more of an expense and it's designed for this use.

[JimK]

I just called the distributor, apparently it is just regular 10 mil paper. Sorry for the noob confusion. ops:

I guess this puts me back to using TB II or something like heatlock for the adhesive. Both seem to have been used here to good effect. I will be finishing up the MDF work this weekend, and probably applying the veneer next weekend.

I found a another nice writeup of someone's first veneering process here:

http://www.ohio.edu/people/schneidw/audio/veneering.html

One thing I found interesting is that he states in one of the tables that TB II takes 350 degrees to reactivate. Is the required temp actually that high?

He also cautions against using any steam from the iron, which I actually saw recommended somewhere else. It would seem like steam might help to keep the veneer from shrinking/drying as much under the iron. Do any of you have any thoughts on the steam issue?

Finally, given that I am going to be covering some surfaces that are 32x12, am I ok with the iron-on method? In digging through every thread I can find on veneering on this site and others, I have seen conflicting opinions about whether splitting will be an issue on a surface of this size.

Thanks.

[Steve Manning]

Jim,

I'm not a veneer expert by any means, but I'll add my vote with cjd and Hdale85 for Heat Lock. I've used it a few times and it's real easy to work with. Joe's site http://www.joewoodworker.com/veneering/glues.htm has some very helpful information on veneering. Having meet Joe, (he lives around the corner from my in-laws), and spending some time looking at his products and asking him questions, he was very helpful in explaining how Heat Lock was developed to help prevent any creeping, a very nice guy.

Steve

[JonMarsh]

I'll chime in for Heat-Lock, also- it works on projects like my M8ta, which have side panels with a veneer area of 43" x 17".

Now, I've never met Joe, unlike Stever, but I have spent a fair amount of time on his site and bought a variety of their products.

Recommended. :T

[PMazz]

Make sure you apply enough glue. Most stories involving bubbles and what not stem from too little. One generous coat on the back of the veneer is usually sufficient but 2 coats are almost always needed on substrates like MDF. Pay special attention to raw edges as they will absorb more than the panel faces. The glue, when dry, has to built up on the surface. If you don't see this, do another coat.

If you have a week in between assembly and veneering, do the final flat sanding right before you veneer. MDF will swell from glued joints and really needs to settle down. If you can, move the raw enclosures into the house for the week instead of leaving them in a garage.

With backed veneer, size doesn't matter () as it's the backer sheet that is bonded to the veneer itself. The adhesive you're using won't interact with the veneer and the finish you use won't interact with the adhesive.

[Steve Manning]

Make sure you apply enough glue. Most stories involving bubbles and what not stem from too little. One generous coat on the back of the veneer is usually sufficient but 2 coats are almost always needed on substrates like MDF. Pay special attention to raw edges as they will absorb more than the panel faces. The glue, when dry, has to built up on the surface. If you don't see this, do another coat.

If you have a week in between assembly and veneering, do the final flat sanding right before you veneer. MDF will swell from glued joints and really needs to settle down. If you can, move the raw enclosures into the house for the week instead of leaving them in a garage.

With backed veneer, size doesn't matter () as it's the backer sheet that is bonded to the veneer itself. The adhesive you're using won't interact with the veneer and the finish you use won't interact with the adhesive.

+1 on the 2 coats thing. I found that out the hard way on my equipment rack build, I got some bubbling. I believe it was due to the paper backing that was on the veneer not being as porous as brands I had used in the past. I discovered some info. (after the fact) on Joe Woodworkers site that would have been helpful up front .......

What kind of substrate can I use for my panel?
Heat Lock will work with a variety of substrate materials such as wood, plywood, MDF and particle board. Make sure the substrate is clean and porous. Some substrates can be made more porous by scuff sanding with 100 grit sandpaper. You can test the porosity of the substrate by placing a few drops of water on the substrate. If the water is not absorbed by the substrate within 10 seconds, you may find that the Heat Lock glue will not work.

What's that they say about reading direction first? h:

[JimK]

Thank you all for the great advice. Based on the numerous favorable responses I have ordered a bottle of heatlock and a glue roller. My wife claims that I am unteachable, but here is proof that that is not always the case. We'll see what she says after I glue up her iron. :P

In a fit of idiocy, I also screwed up part of the routing for the front piece of the baffle. I really like the jasper jig, but it is very easy to put the index pin into an incorrect hole. They really should make alternating index lines out of different colors or thicknesses. I will now get a chance to further practice my skills by re-cutting that piece. It will give me something to do while the heatlock crawls toward me via UPS ground. I am also working on the crossover. It might be time to start an actual build thread....

[PassingInterest]

After a successful test-route, I always mark the pin hole with a sharpie marker on the clear-plastic side. A tissue damp with alcohol will clean off any old sharpie marks. It works for me.

[Hank]

I'm the die-hard contact cement user here - many years of use with zero bubbles and detachment. I've used Heat-Lock, but for me it took as much or more time than contact cement. Secret is apply several psi after positioning and smoothing of the veneer (I only use 10-mil paper-backed) I use a 3/4" thick oak board with one edge slightly sanded to break the sharp edge. I set the cabinet on the floor, hold the board (which is longer than any cabinet side dimension) with both hands, and lean into it, rubbing across and then with the veneer grain. My veneer application sequence is:
Back of cabinet
Bottom of cabinet
One piece wrap of front (3/4" radius vertical edge roundovers) and sides.
Top

We'll see what she says after I glue up her iron.

Conflict avoidance: buy your own iron - cheap insurance against messing up your supervisor's iron :W

I do the PassingInterest Sharpie thing too, on pivot points that aren't covered by my router base.

[JonMarsh]

After a successful test-route, I always mark the pin hole with a sharpie marker on the clear-plastic side. A tissue damp with alcohol will clean off any old sharpie marks. It works for me.

My standard technique, too!

[CADman_ks]

...

Conflict avoidance: buy your own iron - cheap insurance against messing up your supervisor's iron :W

That's great advice indeed, and a cheap iron from Walmart is pretty cheap insurance.

But one thing that I did was to use an old t-shirt between the iron and the veneer. That kept the glue away from the iron face, and kept me from burning the face of the veneer accidentally, more cheap insurance...

[JonMarsh]

That's great advice indeed, and a cheap iron from Walmart is pretty cheap insurance.

But one thing that I did was to use an old t-shirt between the iron and the veneer. That kept the glue away from the iron face, and kept me from burning the face of the veneer accidentally, more cheap insurance...

Also my standard technique- and good material for the woodworking thread. Will have to see if I can copy, not just move, some of these posts.

[CADman_ks]

Also my standard technique- and good material for the woodworking thread. Will have to see if I can copy, not just move, some of these posts.

While I wouldn't even consider doing this without "something" between the iron and the veneer, I did watch some youtube videos of a "professional" doing it with an iron, and it was doing it without anything in there.

I wouldn't take that risk, but I guess that it works...

[Mark_1042]

I'm the die-hard contact cement user here - many years of use with zero bubbles and detachment. I've used Heat-Lock, but for me it took as much or more time than contact cement. Secret is apply several psi after positioning and smoothing of the veneer (I only use 10-mil paper-backed) I use a 3/4" thick oak board with one edge slightly sanded to break the sharp edge. I set the cabinet on the floor, hold the board (which is longer than any cabinet side dimension) with both hands, and lean into it, rubbing across and then with the veneer grain. My veneer application sequence is:
Back of cabinet
Bottom of cabinet
One piece wrap of front (3/4" radius vertical edge roundovers) and sides.
Top

Conflict avoidance: buy your own iron - cheap insurance against messing up your supervisor's iron :W

I've been thinking about switching to using contact cement myself. I used the heat lock glue for my sub and one other project, and like you say I found that it took a fair amount of time to get the job done. And in addition, Heat Lock glue can get a little expensive (I don't think I'm getting the amount of coverage stated on the bottle).

I've also been considering just using Titebond or Titebond and iron on method, but still need to try a couple test pieces. I guess I'm still sort of searching for a method that works for me.

[cjd]

I don't think time is the reason to avoid contact cement - I think that it's more finicky and tougher to recover from mistakes like "oh shit, a corner just touched and stuck and wasn't aligned right at all!"

Some of the solvent based contact cements are also just plain horrible to work with due to fumes, too.

C

[CADman_ks]

I don't think time is the reason to avoid contact cement - I think that it's more finicky and tougher to recover from mistakes like "oh shit, a corner just touched and stuck and wasn't aligned right at all!"
....

LOL! I've never done contact cement on veneer, but I have done it a couple of times on Formica.

Even there, you get everything lined up, and then you "hope" for the best! The last time that I did it, I thought that everything was PERFECT, and then I started pulling the dowels that were holding it up. Something wasn't quite "perfect" in the first one that I pulled, and I ended up not quite in the right place on the other end. Had no choice but to put a bigger bead of caulk on there. There's no getting it off, or at least I don't think so.

It is definitely one of the she-ot moments indeed...

[PMazz]

While I wouldn't even consider doing this without "something" between the iron and the veneer, I did watch some youtube videos of a "professional" doing it with an iron, and it was doing it without anything in there.

I wouldn't take that risk, but I guess that it works...

I only use the iron directly because I follow it along with a veneer scraper. If your surface (or iron) isn't perfectly flat you'll heat the area but not apply sufficient pressure to achieve a good bond. If you're scorching the veneer, you're scorching the adhesive.

[PMazz]

If you want to try contact adhesive, 3M has a new(ish) spray available. Series 20 spray is a clear spray that's much easier to apply than the old tried and true Spray 90.

Spray 20

[Hank]

thanks Pete - I didn't want to venture into "advertising" - been there too much with the blue painter's masking tape :B

[PMazz]

Well, if your company would stop making great products I would stop using them! :T

[CADman_ks]

I only use the iron directly because I follow it along with a veneer scraper. If your surface (or iron) isn't perfectly flat you'll heat the area but not apply sufficient pressure to achieve a good bond. If you're scorching the veneer, you're scorching the adhesive.

I follow too with a home-made veneer scraper, made out of a piece of MDF. Not as effective as following directly behind, but it appeared to work. I was able to "hear" the areas that were not adhered totally, and then I could go back over those areas and then hit them again with the scraper block.

Another reason that I used the t-shirt, was that I was scared that the iron might leave "skid" marks on the veneer. Is that something that happens?, or is that not something to be concerned about? (that might depend on veneer species as well)...

[JonMarsh]

I follow too with a home-made veneer scraper, made out of a piece of MDF. Not as effective as following directly behind, but it appeared to work. I was able to "hear" the areas that were not adhered totally, and then I could go back over those areas and then hit them again with the scraper block.

Another reason that I used the t-shirt, was that I was scared that the iron might leave "skid" marks on the veneer. Is that something that happens?, or is that not something to be concerned about? (that might depend on veneer species as well)...

You know, you can get irons with teflon coated bottoms if you don't buy the cheapest one... :W

[PMazz]

I follow too with a home-made veneer scraper, made out of a piece of MDF. Not as effective as following directly behind, but it appeared to work. I was able to "hear" the areas that were not adhered totally, and then I could go back over those areas and then hit them again with the scraper block.

Another reason that I used the t-shirt, was that I was scared that the iron might leave "skid" marks on the veneer. Is that something that happens?, or is that not something to be concerned about? (that might depend on veneer species as well)...

You can't wait too long to apply pressure. I work with both hands and follow right behind the iron with the scraper.

I've been leaving skid marks for years but that's kind of personal. :E The iron I use has left some darker marks from the bottom of the iron but nothing that wouldn't sand right off. If you're burning the veneer you're applying too much heat or moving too slowly.

[Mark_1042]

One thing I've been wondering about lately is which types of glue are better when it comes to seasonal humidity changes. Wisconsin winters can get pretty cold, and you can only humidify the house to about 30% when the temps are near zero (unless you want a nice layer of frost on the inside of your windows - or if you have some awesome windows).

Veneer Supplies indicates that urea-formeldahyde is the best, but I haven't seen too many people report issues with different types of adhesives. Most of the problems I've read about on the forums seemed to have more to do with the manner of application than the type of adhesive which was used. There was one guy at the Tech Talk forum though, who said he veneered his speakers in the middle of a cold/dry Michigan winter and had some bubbling problems when the more humid summer air rolled in - bad enough that he had to re-veneer the speakers, apparently.

[JimK]

You know, you can get irons with teflon coated bottoms if you don't buy the cheapest one... :W

You can also now get irons with ceramic coated, titanium bottoms. :T

I love titanium. It makes me happy.

[PMazz]

Most of the problems I've read about on the forums seemed to have more to do with the manner of application than the type of adhesive which was used.

Bingo!

[PMazz]

I love titanium. It makes me happy.

I much prefer unobtanium. :B

[JonMarsh]

You can also now get irons with ceramic coated, titanium bottoms. :T

I love titanium. It makes me happy.

Ooh, I have a new reason for living- upgrading my iron! :rofl:

[JimK]

veneer trimming bit?

One more question on the veneering: I have a Bosch Colt trim router that I am planning to use to do the final edge trimming of the veneer. I will need to buy a new bit for this purpose. What would produce the cleanest edge cut?

I'm thinking of something from Freud with a bearing, but straight cut or spiral? Up cut or down cut?

I'm hoping I didn't just step into a holy war...

[PassingInterest]

Spiral Down-Cut.

[PMazz]

I just use a sharp 2 flute trimmer but a down-cut will be the surest.