@bob-wickham

Hi Bob

I think the answer is in the 1926-31 Fisher Body Manual found here:

https://chevy.oldcarmanualproject.com/fisher/2632fbsm/2631fbsm006.html

Hope that helps.  🙂

@ole-olson thankyou Ole, that’s exactly what I needed to know.

Back then they used "hide" glue. Over the years it deteriorates leaving only a discoloration on the originally glued joint. 

@chip  @bob-wickham

I believe hide glue is what was and is used in musical instruments.

My engineer son used it when he built his own nyckelharpa.

Apparently it is what was used in all of the old violins etc.

I asked why it would still be used when there are probably much better glues made today.

He told me it is because it can be steamed apart if necessary to disassemble an instrument for repairs.

Musical instruments of course are usually kept in an environment of fairly well controlled temperature and humidity.

Old cars usually have not.

Maybe that explains why there are really old intact violins, while the glue disappears from the wood joints in old cars?

@bob-wickham, @chip, @ole-olson:

Check out this thread in the old forums: https://vccachat.org/ubbthreads.php/topics/425487/glue-vs-preservative.html

In particular, read ChisTech's post. He is a well-known and respected restorer who frequently works on wood body structures.

Cheers, Dean

I know a member who used hide glue when building his 32. He was very appreciative of the fact that heat released the glue as he had made a major error in assembly. 

I have a booklet written by a person who did wood auto body restorations. It mentions using glues and epoxies (liquid and paste type) . 

@rustoholic @bob-wickham @chip @steve-d

I just had coffee with my son.  🙂

He reminded me of a couple of interesting things.

Another reason that hide glue is still used on musical instruments is that it does not suffer from "creep" when under constant force as a strung instrument is.

Also, a huge advantage to the stuff is that if you heat/steam a joint apart, you don't need to sand down to clean wood again to get good adhesion.

Hide glue will apparently adhere to the old layer of glue just fine, unlike most other wood glues.

This is of course a major consideration with instruments where loss of wood is unacceptable.

(this would likely be a consideration with mortise and tenon joints as well)

Hide glue is processed natural material so is susceptible to being "eaten" by bacteria and molds and mildew in warm humid environments. While it may be nearly perfect for instruments it is not as long lasting in vehicles subject to the outdoor environment. 

Thank you everyone, some very good information there. Good tip about the soap to help with the screws. The brand names of products in the US or Canada are almost never available in Australia but we do have some high quality wood glue products. 

Soap on screws is a long held urban legend. Yes, it can lubricate the threads but at what cost. Soap is a surfactant that draws and holds water. Anything waxy, even lip balm is better.

<CLICK ME>

Let me offer a slight correction. Soaps have an attraction for water depending on how they are put together. Soaps are a combination of a metal (Sodium, Potassium, Lithium) salt or oxide and fat or fatty acid. The metal end of the molecule is soluble in water. The fat end is soluble in oils. They work by suspending oils in water. There are few real soaps on the market. Lye soap in one. Most of what we call soap is actually a detergent. It is similar in structure but uses man made components not naturally occurring molecules. In most cases the attraction for water is less than the cellulose in the wood. If you are concerned that a soap might attract moisture then use a wax like paraffin or candle wax to lubricate the screws. It is a good use for the unburned ends of birthday candles. 

I can verify that it is easier to put wood screws in with paraffin (candle wax) smeared on the threads.

Another use of paraffin is in removing stuck or rusted bolts. I learned this trick from a good friend who is a local high school auto shop teacher. Just heat the stuck bolt using a hand-held propane torch (it doesn't have to get red) and touch the candle to where the head of the bolt is seated. The wax will 'wick' down the threads and act as a lubricant that helps to get the bolt out. I've used this method quite a few times with a lot of success. 😉

Cheers, Dean

Thank you everyone. All great advice and very interesting about the musical instruments. 
Once I have completed the frame is it the done thing to paint it, or treat it in any way?. 
I’m using eucalyptus hardwood. I know eucalyptus grows in places like California and is almost a weed, but here it’s a very hard durable timber that would last forever if protected from the elements