Wood flour?

[Bruce Kershaw]

I already have it.

Any reason I should use something else, and shouldn't use wood flour to thicken epoxy for gluing?

Thanks

[Charlie Jones]

nope- use it all the time, except when I want a really high strength join. Like in a highly stressed area. Then I'll use micro fibers or silica

[capt jake]

I already have it.

Any reason I should use something else, and shouldn't use wood flour to thicken epoxy for gluing?

Thanks

No reason to use anything else.

Yes.

I have found that I like maple flour better than Pine.  Also, Walnut is great stuff also.  The Maple and Walnut seem to mix in smoother and the Pine seems to have a rough consistency. 

[Konrad]

The range of trade off's among the various thickening agents is Strength vs. Sandability.

e.g. Silica = high strength, but hard to sand.  On the other end of the spectrum is microbaloons: easy to sand, but low strength.

Wood flour falls into the middle of that range, so it's a good all-around agent.

As a side note, I checked several hardwood suppliers in Lincoln and Omaha, and when I asked for "wood flour" they kind of looked at me like that RCA dog into the megaphone.  Their reply was always, "Uh, say again..?"

:

[capt jake]

I had to mail order my flour.  I bought the Pine from Raka, the Walnut and Maple from boatbuilder.org .  Though I am not sure what Joel's status is presently.

[Bruce Kershaw]

Thanks, Guys.

I have maple flour that I got from Raka back when I got the epoxy for my Weekender.

Yep... It's all been sitting in my garage all these years.  :

I'll make sure nothings growing in it before I use it.

[lewisboats]

dont ask for wood flour ask for thier disk or belt sanding dust from the collectors. you'll get a bit of microscopic grit from the sanding medium too but it can only strengthen things. 

Steve

[Bruce Kershaw]

dont ask for wood flour ask for thier disk or belt sanding dust from the collectors.

That'll work if they aren't hooked up to the same collector system as the planers, shapers, moulders, etc. :-\

[PAR]

There's a huge difference (literally) between wood flour and the dust from a sander. Most of the flour you buy is ground very fine, filtered and strained to insure uniform partial size. The stuff coming from the belt sander is very coarse by compairision, which usualy makes it lumpy, and difficult to spread, when mixed with epoxy, not to mention a lot more work to fair, plus it's also weaker.

[Greg Luckett]

I agree as I get wood flour from Duckworks, and also save saw dust from the band saw (mostly) and the belt sander too.  I usally mix it partly with microfibers but do not use the collected dust unless I am trying to match the color.  I have a jar with mahogany sawdust, another with white oak, another with Okume, and one that is just a mix of whatever was available.  The clumping is a problem so I use the flour most of the time.

[lbrewer]

I usually buy mine as well, but in a pinch I'll use dust from the collection bag on my belt sander.  If I am trying to match the color of a wood, I'll specifically put on a 120 grit or finer belt on it and add a bit of fumed silica.  Without the silica, the sanding dust/epoxy is usually darker than its corresponding wood.  The silica lightens the color some and helps smooth out the fillet.