Sharpening Rasps

[Prashun Patel]

I need to sharpen some rasps. I've heard good things about Boggs, but I'd like quicker results if possible.

Is sharpening with Citric acid hard to do? Is it an old wives' tale?

[Paul Saffold]

A search on the creek will give you good information. Many use it to de-rust and watch the process closely to prevent etching the steel. If you are using the process to sharpen the etching is just what you want. I have left items in for a couple of days if they were in bad shape. These were flea market rasp with nothing to lose.

This link gives detailed info and was posted by another creeker, Ken Shepard.

http://www.tttg.org.au/php/tttg_Page.php?n=15&a=28

Good luck. Paul

[Scott Cardais]

Watching a video of Sam Maloof on the Woodworking Channel yesterday, he suggested sharpening rasps by putting them in a bath of muriatic acid. The acid needs to be in a glass bowl (Pyrex for example) and he also suggested doing this outside so the fumes don't rust the metal tables of the equipment in your shop.

I think muriatic acid is available at DIY centers. It's used to etch concrete.

Hope this helps.

Scott C.

[Prashun Patel]

Thanks, Guys. Yep, I did a search here on SMC and found a couple threads, but I couldn't find detailed descriptions - and I was left with the distinct impression that there's a good chance you can ruin a rasp this way based on how it was hardened. Just wanted a little more detail.

Muriatic is a might stronger than citric acid. I'm staying away from that. My company uses citric acid by the buttload; I love the stuff...

[george wilson]

I hope they don't use it by the buttload!! :)

[Rod Sheridan]

I hope they don't use it by the buttload!! :)

I think that much muriatic acid would result in diaper rash:D

[Rick Whitehead]

Yes, I have sharpened files and rasps with citric acid.It does work!
I don't remember the concentration of the acid I used. I think it was about 1 oz/gallon. It was fairly weak, as it took a while before the files were sharp.I just kept checking them every couple of days until I thought they were sharp enough.
Hope this is of some help. I'm not an expert on this, just a guy who's done it once.
Rick

[Brian Kent]

Are you talking about your new dragon rasps? They shouldn't be dull so soon.