HeatLok glue / Veneering

[andrew whicker]

Hi,

What are your thoughts on using HeatLok glue on raw veneer?

I'm still wading these speaker boxes. I'm pretty good so far at small boxes, but I'm so tired of clamping with slippery PVA glue. it's way too easy to misalign the grains. It simply won't work on a large speaker cabinet. I'm waiting for my Urea glue to see how that works. Maybe it is more tacky.

I was thinking of using a vacuum bag from day 1 of trying to get this work. However, I'm slowly moving away from that idea. I get so much conflicting info. The positives seem to be that I can use high quality adhesives. I was also hoping that moving veneers would be partially / mostly solved in a bag. Other positives are that I could use veneer on other furniture projects. It's not an investment I'm worried about making long term if I can have some confidence that it will work for this contract work.

I ran across HeatLok glue w/ clothing iron. Seems like an interesting idea, but I don't want to end up using an adhesive that causes me problems in the future... these are high end speaker cabinets.

If you have experience with the glue, how has it held up long term?

I'm really trying to find reasons to use the bag method (complicated shapes, lots of future uses, etc). I'm having a hard time finding out what people WITH ACTUAL EXPERIENCE do versus armchair quarterbacks when it comes to using vacuum presses. Seems experts DO use vacuum presses with success, but it's hard to find details. I'm about to just go for it and learn by experimenting. Maybe when I'm an expert, I'll actual post good info :D


cheers,

PS:

I have tried using blue tape to locate the veneer panel on my small boxes (5" x 5" x 5" ish) with good luck keeping location. However, the pressing causes the tape to damage the wood surface when I remove it (it pulls off some of the veneer). Are other tapes better?

[Stewart Lang]

How thick of veneer are you using?

[andrew whicker]

As thick as I can find. I found some 1/25" ("thick") to 1/50".

I'd like to do re-sawn stuff in the future (1/16").

[roger wiegand]

I used it for the first time this summer. It worked great and was extremely easy to use. Much better result in my hands than using a vacuum bag in terms of getting a perfectly flat application (caveat, I'm just trying vacuum bagging for the first time in the last month-- my third attempt was better than my second, which was way better than the first that went into the pizza oven as fuel).

I can't speak to the longevity of the bond, but things I veneered forty some years ago using the same technique with Titebond have held up perfectly so far. The heatlock is better for sanding than Titebond.

The biggest pieces I've done are about 2x3 ft. It was a breeze to use on some curved corners.

[Kevin Jenness]

If you have no choice but to veneer pre-assembled boxes and require accurate alignment of the grain around the corners then Heatlok or hammered hide glue will probably give the best results. As you have found, it is difficult to keep veneers from swimming around on a film of liquid glue. You will have the same problem with UF glue, or any glue in a vacuum press. A vacuum bag is the most versatile and economical press for a small shop, but it is not going to solve your specific problem.

If you are going to be using paperback veneer, consider using FSV glue.

As far as longevity, hide glue has been used for thousands of years and its characteristics are well known. You might be able to track down the reviewers of Heatlok on the veneer supplies website for a more in-depth assessment.

For the "best", "high end" solution, use UF glue in a press, whether vacuum or otherwise, with a balancing backer veneer of similar characteristics as the face veneer. Lay up a continuous panel, then miterfold a box together. I understand that is not what you are faced with, but that is the best way to get a perfect match at 3 out of four corners.

The thicker the veneer, the more your corners will show end grain when veneering an assembled box, and I suspect you would have more difficulty getting heat on the glueline with an iron.

I believe the veneer supplies site has some adhesive tape that they recommend over blue tape for veneer. Worth a try. Veneer tape will release without tearout. It works well for seaming veneer, but any tape used for alignment of veneer on a panel has always been iffy for me.

For general info on veneering, register on the vacupress veneering forum. There is an extensive archive you may find helpful. Daryl Keil has experience with the "bladder inside bag" technique, and can probably give you as good advice as anyone on your project.

[Don Stephan]

For years I have used clear packing (shipping?) tape to hold veneer in place for vacuum veneering. Care is needed when removing as some woods will want to lift slivers. Lifting across the grain may help. Once I used an iron on just dried PVA to glue book matched olive ash veneer onto a five sided sculpture stand (no bottom). The heat of the iron caused the seams to separate in places, spent two days with shellac and touch up fresco powders trying to hide the filler. I'll never use an iron again with veneer.

Veneer is likely to slip with almost any adhesive. If necessary, modify the design so a "neutral" veneer is around the edges - for example a fine burl pattern with no grain, quartersawn grain parallel to the edges, figure and grain pattern free - so there is no matching across edges of a speaker box or similar.

And experiment as many times as needed.

[Mel Fulks]

Andrew, read up on the old art of using hot hide glue for veneer. It’s old and fast ....but a skill . Try it . I’m sure there are some guys here
who will be glad to help you learn something that most don’t even try.

[Phil Mueller]

I’ve experienced the same fiber damage using blue tape. I found soaking the tape with a little mineral spirits helped reduce tear out considerably. I switched to a cheap walmart masking tape (almost see through) and had better luck, but still use either mineral spirits or Goo Gone first. I’ve also heard just warming it with a hair dryer will work also, but haven’t tried it. Seems like you’re beyond the tape thing though.

I just watched a Peter Rawlings vid where he used HeatLok and iron method to cover a couple of speaker boxes. Really seems like the way to go.

[roger wiegand]

I'm no expert, I've used the old-fashioned gum-backed paper veneer tape (https://www.veneersupplies.com/products/Veneer-Tape-34-x-650.html) to hold pieces together for gluing. It seems to work just fine. What am I missing? It seems like painters tape or packing tape would (literally) gum up the works. The paper tape comes off readily when slightly moistened and the gelatin glue residue sands away easily.

[Phil Mueller]

Roger, if it’s critical that a piece of veneer is aligned “perfectly” in a certain orientation to the substrate, it’s not unusual to apply the glue, put down the veneer, and then tape the veneer to the substrate to keep it from moving when putting between cauls, applying clamps or putting it into the vacuum bag, or whatever. Even when applying pressure, it can move slightly which effects the outcome.

Standard veneer tape needs a bit of time (albeit not long) to dry...often more time than what is ideal before the glue starts to set up. I’ve never tried doing this with veneer tape, however, given how sticky it is, it may work fine. Might have to try it on the next project.

[andrew whicker]

Mel,

You're talking about 'hammering' on veneer?

[Mel Fulks]

Yes, look it up. It’s really more of a squeegee.

[andrew whicker]

I've been looking it up. I initially dismissed it (due to complexity), but I'm starting to see the value. I especially enjoy zero clamping. I am curious about the veneer thickness limit.

And does the hide glue soak all the way thru the veneer? That must obviously change the look of the wood. I'm still figuring it out...

[roger wiegand]

Thanks, I misunderstood the use.


Roger, if it’s critical that a piece of veneer is aligned “perfectly” in a certain orientation to the substrate, it’s not unusual to apply the glue, put down the veneer, and then tape the veneer to the substrate to keep it from moving when putting between cauls, applying clamps or putting it into the vacuum bag, or whatever. Even when applying pressure, it can move slightly which effects the outcome.

Standard veneer tape needs a bit of time (albeit not long) to dry...often more time than what is ideal before the glue starts to set up. I’ve never tried doing this with veneer tape, however, given how sticky it is, it may work fine. Might have to try it on the next project.

[Mel Fulks]

What I’ve heard is that if the hide glue does go thru in some places is that it does not make those spots take stains differently or change the
wood color.

[Mel Fulks]

Oops! Neglected the thickness . I think you could go up to 1/16th without clamps if the veneer is flat...not all bubbled up. I do remember
that if the veneer is close to a 1/8th it’s often called a “facing “. I’m guessing that today’s thin veneer would be pretty easy to “hammer”.
And with today’s plastic grocery bags ,you could use that between two pieces of same size and put a few spring clamps around the perimeter.

[andrew whicker]

There's an interesting video of a guy flattening veneer with hide glue with clamps and plastic wrap over a few days. After the veneer is flattened, he then hammers it on to the drawer face.

I've now seen two main ideas:

- using a clothing iron for heat
- using a hot air blower (shop type) for heat

As with most things, there's apparently different methods for different people.

[Mel Fulks]

In a large shop providing furniture for several branch retail stores , the wood parts would be warmed on thick sheet steel resting on gang
radiators. Crock Pot electric cooking pots are a lot like electric glue pots and are a lot cheaper.