Balsa strops

blame it on god

blame it on god

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Feb 21, 2013
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What do you guys think? At what point does balsa become MORE abrasive than the stropping compound? Like is .25 micron a waste on a balsa strop?

Just wondering cause I love the balsa strops I have and have another one coming. So far I have 2, The lowest of them is 2 micron, the higher being 3.5 micron.

The last stone I use is a 10k chosera. Could I just face the strops I have and go 1m, .5m and .25m?

Or is balsa already naturally above .5 micron?

Thanks guys!
Jim.
 
I have a balsa strop that I run with 1 micron spray. There isn't any set grit range/stone I finish with before the strop, it could be anything from a 600 or 1000 ep stone to a EF or EEF DMT now. Sometimes I don't always strop either.

I would be interested in what the general consensus is too on the above question. I never really considered "balsa" to be an "abrasive", just a substrate to hold it (the spray).
 
Murray Carter strops with newspaper. I would imagine on the molecular level, balsa is a very thick newsprint.
 
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The balsa I've used seems very, very minimally abrasive by itself, at least when used against steel. Used by itself, with no compound, I haven't seen any indication that it abrades an edge at all. And the soft nature of it also limits it's ability to straighten a rolled edge, unless it's very fine & thin. I notice more of a benefit in stropping on bare leather, by comparison, and the leather's silicates are WAY smaller than even 0.25µ in size; perhaps by an order of magnitude.

I've read there are different grades of 'balsa'; some are apparently firmer/denser than others. That should impact, to some degree, how effective it could be on it's own. Still don't think they'd add much, in terms of abrasiveness; but they might be more useful for edge-realigning tasks, as with a bare-leather strop.

Balsa really excels in how it provides a great 'bed' for abrasive compounds to work. Balsa strops used with compounds really seem to load up with swarf very quickly, and that's a testament to how aggressively it allows a particular compound to work. Seems to be a great surface into which the abrasive can dig in & hold; the combination of the two is what's special about it, as I see it.


David
 
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I'd think the balsa by itself might act to burnish maybe but likely contributes very few abrasives. Any silicates in its cell structure would probably be water soluble (salts - not very abrasive) and probably not silica (oxides - more abrasive). I cannot imagine what other abrasives might make their way into the wood, but I don't really know much about it. Is possible the salts increase any burnishing effect, but will still likely qualify as a very small grit value if it could even be classified as such.

Paper has all manner of intentionally added silicates for binders and fillers, and titanium dioxide occasionally as a whitener. I can verify the burnishing effect of paper at higher pressure, and the polishing action at regular pressure.

Just a guess but I imagine you could go down to .25u on balsa.
 
Thanks guys.

I guess I'm gonna face mill the 3.5 tomorrow at work.

One of the reasons I like them so much is that they DO make a lot of swarf relative to their grit size. And there's no rounding of the apex.
 
Well today was almost a success. I was sanding the back of the strop to make sure all was good an flat. Then the piece of balsa came off, literally just slid off.

Got all the glue off and straightened the blank as much as possible. I'll mill it dead flat tomorrow, but I'm going to leave the glue side a little rough for extra grip. Then two part epoxy it all back together.

Actually doing this to both balsa strops. A little heat the other one lifted right off. Probably going to do the new one when it gets here. Whatever glue CKTG uses is not all that good. (I've had chosera stones lift before too.)
 
Thanks for the link, but I use these on my edge pro. Though now that I have a few blanks laying around I'll probably just make my own in the future.
 
blame it on god said:
Thanks for the link, but I use these on my edge pro. Though now that I have a few blanks laying around I'll probably just make my own in the future.
Click to expand...

Just make your own. That's what I did, blanks included.

Take a 1/8"x1" aluminum strip from lowes or home depot (if you can find a metal supply place it will be cheaper, but for one piece it's not bad). Then get you some 1/16"x1" balsa strips from Hobby Lobby or some other hobby store (ones that cater to the R/C hobbies and crafts usually have good selections, art supply stores too but they can be more expensive). Cut the aluminum in to 6.25" to 6.375" pieces (measure your EP's to get exact), then file or grind a chamfered edge at about a 45deg angle half way through the small edges, same side. Don't grind to a point, leave a blunt flat edge. Then cut 6" pieces of balsa. Lay over top the aluminum, chamfer side = balsa side. Use CA, super glue (same stufff), etc to bond together.

Just a bit of work, but for a few bucks you can have 3 or 4 mounted strops.
 
I don't like balsa as of right now, having good results with plain leather. Most of the time I get the burr down on my 5000 stone pretty well, and I really don't need to strop on anything else.
 
KC8QVO said:
Just make your own. That's what I did, blanks included.

Take a 1/8"x1" aluminum strip from lowes or home depot (if you can find a metal supply place it will be cheaper, but for one piece it's not bad). Then get you some 1/16"x1" balsa strips from Hobby Lobby or some other hobby store (ones that cater to the R/C hobbies and crafts usually have good selections, art supply stores too but they can be more expensive). Cut the aluminum in to 6.25" to 6.375" pieces (measure your EP's to get exact), then file or grind a chamfered edge at about a 45deg angle half way through the small edges, same side. Don't grind to a point, leave a blunt flat edge. Then cut 6" pieces of balsa. Lay over top the aluminum, chamfer side = balsa side. Use CA, super glue (same stufff), etc to bond together.

Just a bit of work, but for a few bucks you can have 3 or 4 mounted strops.
Click to expand...

I am a machinist and was eyeballing some materials today. Found some slightly magnetic stainless 1-1/8 x 1/4 that I think I'm going to use.

I rescued one strop today. Got the base flat within .002 and mounted a piece of 1/4" phenolic sheet to it and the balsa to that. Re-machined the 45° end cuts of the stainless base. Epoxy everything together, did some cutting and the final product is .001" parallel and .0006 flat.


20140312_235857.jpg
 
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