Making Wood Flour

[Tom Hoffman]

After spending an hour trying to sand enough WRC to get some fine dust for wood flout filler to use with some epoxy, I finally got so frustrated, that I vacumed up a big pile left over from sanding with 36 grit paper and took it to the kitchen where I ran it throught the.....

ULTIMATE CHOPPER!!!!

You know the one where the guy goes A-one, A-two, A-three (with a german accent) and chops up a brick.

Well, it worked.....

Screened the fist batch and re ran it and it is quite acceptable.

Now just have to hide the CHOPPER from SWMBO....

[Bob Cleek]

Next time around, you'd do a lot better to buy the additives for your epoxy. A few bucks for microbaloons or whatever and you'll save a ton of time. They work better, too. Adding sawdust to epoxy is a pretty primitive approach, although it does work. The specific materials now available have pretty much eliminated the need to make your own sawdust!

[Tom Hoffman]

The reason I did it is because WRC is not available at least in the sources that I have, and I wanted to try it just to see. I am always a little backward anyway.

[MJC]

Chuckle. Laugh. Laugh louder. I've done thaat!

[Scott Rosen]

Sawdust is okay. Sanding dust may not be. When you create wood flour by sanding, you will get some of the sandpaper residue and grit in your wood flour. That may or may not matter depending on what you use the wood flour for, and depending on what kind of sandpaper you use.

I'd take Bob's advice and buy the wood flour, unless you have a ready-made source handy; say if you mill a lot of lumber and and are careful about the dust collection.

[George Roberts]

Tom Hoffman ---

I just take the sanding dust off my plywood floor and add it to epoxy.

Very few materials around my shop will bother the epoxy curing reaction. A bit of sandpaper grit doed not seem to be a bother.

[landlocked sailor]

I save the dust from the collecting cup on my Random orbit sander. It tends to me fine clean and uniform. Rick

[dmede]

Originally posted by landlocked sailor:
I save the dust from the collecting cup on my Random orbit sander. It tends to me fine clean and uniform. Ricksame here, seems to work fine, no issues with contamination from the paper that I am aware of.

Its a good source of free filler. I often mix it with store bought filler 1:1 just to sreatch it. It is not a good choice if you want a easily sandable filler.

[ 06-08-2005, 07:25 PM: Message edited by: dmede ]

[Tom Lathrop]

I buy wood flour but I also save sanding dust from any machine that has a dust bag. Also use sawdust occasionally for large filets that will not be finished bright. Coarse dust should not be mixed as thick as wood flour since the large particles will soak up a bit of resin and could end up too dry.

There is no problem with sanding grit.

[JimConlin]

More Mouse Milking!

Google for "wood flour" and you'll find that it's fairly quality controlled and as cheap as dirt. That's reasonable because it's not much good as a boo-boo filler being much too dark and hard to sand. I use it occasionally as a structural filler material where its coarse texture will be ground out.

[Cuyahoga Chuck]

In the pantheon of thickeners each can be rated for strength. Fiobers, liked chopped 'glass are at the top. Wood flour is rated as medium strength. Some of the thickeners designed for easy sanding are at the bottom of the chart.
So wood flour is cheap and somewhat muscular. And wood flour can be had in a dizzying array of tones to match or contrast the decore of your hull. Not a bad deal!

Charlie

[Scott Rosen]

I've found that some sandpaper imparts an unwanted color. The 3M gold papers are ones I've had problems with.

Whatever floats your boat.

[Tom Lathrop]

Originally posted by JimConlin:
More Mouse Milking!

.I would agree that sanding just to make dust is not a good use of time, machines or sandpaper. I use my belt sander mostly as an edge sander or thickness sander for ceiling strips, etc. Sometimes the bag must be emptied several time for a single job.

Put it in a container for myself or for the local boatbuilding class or dump it?

Never tried to milk a mouse. Just how do you go about it?

[John Turpin]

Psssst. Your wife's kitchen sifter might just be useful in the production of contraband wood flour. You didn't hear it from me. I would never do that.

[Nicholas Carey]

Originally posted by Scott Rosen:
I've found that some sandpaper imparts an unwanted color. The 3M gold papers are ones I've had problems with.Also bear in mind that that unwanted gold "color" is the stearate coating 3m applies to the sandpaper.

Stearates (usually zinc stearate) are metallic soaps and are applied to sandpaper to make the paper "non-loading". They've been implicated in causing finishing problems such as fisheyes, and I suspect might cause problems with glue adhesion.

Given how cheap structural additives are:

* 5 quarts of wood flour runs about $11.30
* 5 quarts of fumed silica runs about $12.36
* milled cotton fibers runs about $2.82 per pound

I can't see anyone spending the time to make your own dust.

[David W Pratt]

For wood flour, I use table saw dust. But have recently fallen in love with PVC microspheres. They are nearly as strong as high density filler, and sand like low density. Pure white.

[Tom Hoffman]

Nick, The reason I did it was for color match, as WRC wood flour is not available any where that I have looked, like I said in my second post, it was an interesting experiment. Besides I am building a boat that will take 300-400 hours, whats one more 1/2 hour????

[Nicholas Carey]

Originally posted by Tom Hoffman:
Nick, The reason I did it was for color match, as WRC wood flour is not available any where that I have looked, like I said in my second post, it was an interesting experiment. Besides I am building a boat that will take 300-400 hours, whats one more 1/2 hour????I suspect that if you experiment, you'll find, regardless of species, that wood flour mixed with epoxy winds up as a dark brown.