Ipe preparation

[Jan Westphal]

Hi folks, just sanded some Ipe laminations for a trilam but have no experience with this wood and read a few scary reports of failing glue lines due to the oily Ipe.

How do you treat this wood before glueing?

I am planning on using a locally made two component glue (no epoxy) called Bindan, made for sea water resistant constructions.

[macbow]

Most recommend scoring the Ipe and all pieces with a toothing plane.
I make lighter weight bows with bamboo and Ipe. I don't score and have never had a problem.
I use Unibond 800 for glue.

When it comes to finish I use shellac as a sealer coat then poly types.mwith out the shellac the poly's sometimes wont work right.

[mikkekeswick]

It's easy to blame a bad glue-up on oily woods....
I used to sand to 80 grit and used titebond 3 for years and never had a single failure.
I now sand to 60 grit and use smooth-on - still no problems.
Whatever you do don't use acetone to 'degrease' it.

[macbow]

Certainly agree with Mike on the no Acetone. It just pulls oil to the surface.

[Ringbill]

I have never heard of not using acetone for prep on oily woods. I have done a fair amount of work with teak (not for bows) and it is considerably less oily to the touch afterwords. I am new to bow building and because of my expierence with teak when I built 2 bows with IPE I sanded with 80grit sandpaper and used acetone before glueing with Unibond 800. Both were under 40#. Another reason I use the acetone is to clean the surface. What would be the recommended way to remove any dust and debris before glue up if not using acetone?

[Roy from Pa]

Denatured Alcohol..

[mikkekeswick]

Or a brush! Compressed air etc
If you use acetone to remove any oil then what you do is simply take a bit of 'surface' oil off. Yes you will get a dirty rag and common sense would tell you that the surface is cleaner now but what happens is more oil get pulled out of the rest of the timber.

[Jan Westphal]

Thanks a lot, first thing is building a toothing plane. Did you know Paul Sellers' poor man's tool videos? Great stuff, I like it simple and functional.

 

[macbow]

Good link, thanks

[PEARL DRUMS]

I've made a bunch of ipe bows. Hickory or boo backed. Zero degreasing done - zero failures. I do it exactly as Mike described. 50 or 80 grit to rough it up and blow it off clean. Sometimes TB3 and sometimes Unibond 800.

[J.F. Miller]

Originally posted by mikkekeswick:
Or a brush! Compressed air etc
If you use acetone to remove any oil then what you do is simply take a bit of 'surface' oil off. Yes you will get a dirty rag and common sense would tell you that the surface is cleaner now but what happens is more oil get pulled out of the rest of the timber.

I totally disagree. how in the world is that pulling more oil from the rest of the wood? unless you are literally submerging your stock in acetone for some amount of time, that isn't going to happen. I've been using many solvents for many purposes for many years in my line of work, and I've never seen anything that would support this claim, which I've heard repeatedly among bowyers. using acetone, MEK, naphtha, lacquer thinner, alcohol or any relatively fast drying solvent will clean the glue surface quite nicely, removing oil and other contaminants from it and flashes off in seconds(acetone and denatured alcohol, anyway) and isn't going to draw more oil from somewhere inside your bow wood. I'm not suggesting that anyone must use solvents to clean their wood before gluing. with the quality of the epoxies we have today, it is probably not necessary, but I've been cleaning all my glue surfaces for over 20 years with acetone, and I recommend it highly. just don't get it on your skin.

[Jan Westphal]

Originally posted by J.F. Miller:
 how in the world is that pulling more oil from the rest of the wood?

I am not a scientist but to me it appears quite logical: oil is taken away (at the surface) by acetone which throws off the balance within the structure of the wood, kind of low pressure situation.

Imagine a water soaked sponge, if you press a towel gently on top some of the water will get soaked off and the surface of the sponge becomes almost dry. Wait some and it will be wet again.

[J.F. Miller]

that analogy doesn't hold much water. what takes minutes with a wet sponge and towel likely takes weeks, months or years for the oils present to leach back to the surface on a piece of heavy, dense hardwood. I'm operating under the assumption that my glue will be quite dry before then. if it were that big of an issue, no sort of film forming finish would ever stick to Ipe. or osage or any other oily wood.