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dp
09-12-2010, 12:01 AM
Found this thread tonight on another forum. Just might have to give it a try as even a cheap Biax is not cheap.

http://www.machinistweb.com/forum/showthread.php?t=501

darryl
09-12-2010, 12:59 AM
Ironic- here I am having just finished scraping a mess of pvc handles I made. All the while I'm thinking there must be a power tool to do this kind of thing. And this post shows up-

darryl
09-12-2010, 01:09 AM
I've been looking for a good way to smooth the saw-cut surfaces on all this pvc stuff I've been working with. Scraping leaves about the best surface finish so far, out of the various methods I've tried. Right now I'm envisioning a belt with a large number of scraper blades poised on it- it would work like a belt sander except it would not smooth the surface by putting millions of narrow grooves in it, but by dragging a hundred or more scraper blades across it. Comments?

The belt would probably be a nightmare to sharpen.

Forrest Addy
09-12-2010, 01:23 AM
Yup works great. If you look you can find a dozen candidate gadgets on which to base a Biax-like scraper.

Consider for light and finishng work: a Porter Cable Cable reciprocating detail sander and a speed control to bring the 4000 strokes per min to a more reasonable level. Make a gizzie that attaches to the P/C mounting feature to hold the blade at a 25 degree angle and make up some smaller than Biax scraper blades.

Black_Moons
09-12-2010, 01:36 AM
Right now I'm envisioning a belt with a large number of scraper blades poised on it- it would work like a belt sander except it would not smooth the surface by putting millions of narrow grooves in it, but by dragging a hundred or more scraper blades across it. Comments?

The belt would probably be a nightmare to sharpen.

Uhhhh.... Maybe im just being silly, But I think we call those files...

darryl
09-12-2010, 01:45 AM
Dang! Already been invented:(

dp
09-12-2010, 02:54 AM
Yup works great. If you look you can find a dozen candidate gadgets on which to base a Biax-like scraper.

Consider for light and finishng work: a Porter Cable Cable reciprocating detail sander and a speed control to bring the 4000 strokes per min to a more reasonable level. Make a gizzie that attaches to the P/C mounting feature to hold the blade at a 25 degree angle and make up some smaller than Biax scraper blades.

I'd considered the HF sawzall clone as it has variable speed, but it did not occur to me that it would be possible to drop in a scotch yoke arrangement to adjust the stroke. That is damned clever.

Black_Moons
09-12-2010, 03:30 AM
Darryl: As an intresting subnote, there is also some 'ordered' sandpapers, like 'trizact'

http://www.eastwood.com/media/catalog/product/cache/1/image/9df78eab33525d08d6e5fb8d27136e95/p28967.jpg (Microscopic view of trizact sandpaper)

http://www.trugrit.com/images/ad-main.jpg (Other weird ordered sandpaper)

Very nifty stuff. Wish it was easyer to find localy.

Evan
09-12-2010, 06:04 AM
I'd considered the HF sawzall clone as it has variable speed, but it did not occur to me that it would be possible to drop in a scotch yoke arrangement to adjust the stroke. That is damned clever.

Considerably less clever but much cheaper and easier is to buy this power scraper from Canadian Tire. I just picked it up on sale for fifty bucks to remove tiles in our bathtub area. It works very well and is very controllable. It has three speeds with a 2mm stroke from 6500 spm to 9600 spm. The actual scraping action is engaged by lightly pushing the scraper blade until it begins to make contact with the reciprocating element inside. This allows for any degree of action from just barely working to full power. I haven't had time to do more than a quick test on some metal but it seems to be very suitable for the job.

http://ixian.ca/pics7/scraper.jpg

DFMiller
09-12-2010, 11:07 AM
Evan.
I see they seem to be stock for $99.00 at local store. Very interesting. Looks useful even if it sucks for metal.
Thanks for the tip

wierdscience
09-12-2010, 11:23 AM
Hmm..I wonder about an air body saw.

lakeside53
09-12-2010, 11:41 AM
As I just bought a nice used Biax, I refuse to read this thread futher :D