vintage glue type for veneer?

[VAsunshine]

Hi everyone! I have been asked by a friend to repair his glovebox from a 1969 Sunbeam Alpine coupe. I have never even seen that car and know nothing about it other that what's obvious in the photos. It has a peeling veneer problem.

I'm a professional woodworker and have enough experience with glues and repairs to know that simply adding glue of the wrong type to a failed glue joint is a recipe for failure again. My hope is that British makers were tradition bound enough into the late 60s to still be using hide glue for veneering their woodwork.

Does anyone here have actual knowledge of typical factory/workshop practice among automotive woodworkers in England circa late 60s?
What sort of glues were used?
I know that a number of synthetic adhesives were developed for the aircraft industry during WWII and I'm afraid that post war industry took them up in general.

This appears to be finished in old, possibly original, nitrocellulose lacquer and it's miraculously flawless with the exception of the lengthwise crack. The delaminated areas do press back together nearly perfectly and the best of all possible worlds would be to not have to do any finish work at all. Moisture behind the finish is likely to cloud it a bit, but that can be fixed.

Hide glue offers numerous advantages when it comes to cleanup of whatever squeeze out ends up on the surface after drying, but it's not going to be the right choice if the original glue was Cascamite or a 2 part urea formaldehyde glue. A PVA glue like Titebond almost certainly was NOT used. Hide glue may well have been used for the veneer and has a very long tradition behind it.

If anyone has actual experience with a similar situation with long term observation of the result afterwards, I'd certainly appreciate tips on what approach was taken. Most of what I've seen on YouTube etc. might looks sort of good in the video, but seems destined to fail with a few years of real world use.

 

[Grantura_MKI]

Why worry about the adhesive. I would use modern veneer with the sticky back already applied. This will solve the problem.

 

[VAsunshine]

But the problem is to preserve the original veneer and its finish. Someone else decided that.

I thought the reasons for worrying about the original adhesive were pretty well explained in my original post. If you have more specific questions let me know and I'm happy to do what I can to answer them.

I have worked with veneer since the late 80s. There is absolutely nothing that I would use sticky back veneer for. If you're happy using it, then more power to you, but it's just not a long term solution in any environment, let alone a car interior.

 

[NutmegCT]

VA - I'll ask a friend who worked on the Morris assembly line in the 1960s. At least it's a start - hoping it sheds some light.
Tom M.

 

[VAsunshine]

Thanks Tom! I'm pretty likely to go with hot hide glue after consulting with several glue technical consultants and some literally world class wooden furniture restoration experts.

But I'm still curious about what might have been used in the British auto industry at that time.

The primary advantage of hide glue is that it reversible. Heat and moisture will loosen it, which is also its primary disadvantage and is why plastic resin and other waterproof glues were developed for the aircraft industry around the time of WWII. The people I have spoken with have pretty much dismissed any concern about hide glue failing in an auto interior mostly due to lack of the amount of moisture required to soften it.

Reversibility is something that matters to me since I have been asked many times to repair things after a bad repair has failed. Careless use of epoxy or polyurethane glue seems to be the go to for a lot of would be restorers and it generally just makes the next round of repair a real nightmare.

 

[PAUL161]

Tom, check out this site and get tips from the pros!
The pros recommend Titebond wood glue. That is what I use.
Woodworkers guild of America!

Woodworking Videos, Classes & More | Woodworkers Guild of America

Watch woodworking videos to learn popular woodworking techniques. Join online woodworking classes learn woodworking skills from a Master Woodworker.

www.wwgoa.com

 

[NutmegCT]

VA - just heard back from the guy. He and his colleagues used Cascamite - altho' we have no idea if today's Cascamite is the same formula as the 1960s.
Hope this helps.
Tom M.

 

[Grantura_MKI]

VA, I figured I’d get slapped at a reply.
The fact is that you can purchase the dash done with the proper lettering, etc already done. Why redo a part that is cracked?
I have used sticky backed veneers in the past with excellent results, and trust me the vehicles are worth way more than a Sunbeam.

 

[VAsunshine]

Very interesting Nutmeg and thanks! I hadn't thought about the Morgan ash frames. Their makers were probably among the earliest automotive of adopters of what was being developed in the aircraft industry. I believe the benefits of those glues would have led to their general adoption relatively quickly.

Cascamite was developed as a replacement for casein (milk protein) based glues in the early 20th century. Casein, like hide glue isn't so great in hot humid environments and wooden aircraft were, at least anecdotally, coming apart at the seams so alternatives were needed.

A PVA based glue like titebond would be wholly inappropriate for use ln any sort of lamination that is subject to stress. It's a thermoplastic that remains flexible, which has its place but not when trying to resist the shear forces a structural lamination is subject to. For repairs, if it wasn't the original glue, it's just one more dissimilar material added to the mix, Even if it was the original glue, it doesn't stick to itself like that.

For anyone who is interested, wooden airplane enthusiasts have been discussing these glues, their pros and cons, and best practices for repair for a while now. There is a great publication I believe put out by the FAA on the repair of wooden aircraft. Obviously the stakes are higher when a wing fails compared to a glovebox, but the principles and materials involved are the same and are well worth taking the time to understand.

Here's a load of information on that subject.

Aircraft Wood and Structural Repair

www.flight-mechanic.com

 

[NutmegCT]

Thanks VA. When Knute Rockne was killed in an airliner crash, as the wing's plywood and glue began to disintegrate, the days of the wooden airliner were numbered.

The cause of the damage was determined to be that the plane's plywood outer skin was bonded to the ribs and spars with water-based aliphatic resin glue and flight in rain had caused the bond to deteriorate to the point that sections of the plywood suddenly separated.

Knute Rockne - Wikipedia

en.wikipedia.org

Tom M.

 

[VAsunshine]

Grantura, I honestly don't know any other way to say that the goal is to restore the original veneer and keep the original finish, per the instructions of the vehicle's owner.

It's not my decision. I have been explicitly told that no other option is acceptable and trust me, not everyone who cares about things like antiques, cars, etc. considers the monetary value of their own possessions or anyone else's relative to them.

 

[Gliderman8]

When I re-veneered my TR6 walnut dash about 20 years ago I used powered pre-catalyzed resin. It has held up perfectly.... no de-lamination what-so-ever. After applying, I used a press that I made to keep the veneer under pressure for 24 hours.
This is what I used...

 

[vping]

This was an interesting read and learned something I knew little about. Done my fair share of woodworking, typically with just PVA. TIL about hide glue, UFG and Csscamite. Thank you

What was the final result? How did this come out and was the client pleased?

 

[Gliderman8]

This was an interesting read and learned something I knew little about. Done my fair share of woodworking, typically with just PVA. TIL about hide glue, UFG and Csscamite. Thank you

What was the final result? How did this come out and was the client pleased?

I can tell you that the glue I used (pre-catalyzed resin) worked perfectly. Twenty years later and no problem at all.
Since I couldn't find a vacuum press, I made my own press from two pieces of plywood with wing nuts to tighten so the veneer was under constant pressure.