Rasping

[Pete W]

Any tips on rasping technique gratefully received

I seem to have great difficulty with rasps and files, usually producing a lot of broken splintery edges instead of the beautifully-shaped curves I see on various forum posts around the world.

Is there a particular technique? Do they only work well on close-grained hardwoods? Words from the wise would be welcome!

 

[engineer one]

in metalworking terms, rasping is the removal of a lot of metal, but in wood working terms it seems to me, that your technique must be different.

i have found that using for instance a micro plane, or an old surform type tool, that the best technique is "draw filing" ie using a motion rather like with a spokeshave, rather than a planing motion.

don't try to remove wood over too large an area at a time. use it almost like sand paper with a light touch, but also don't forget that rasps are very coarse and will attempt to remove tons of material, so your technique is most important.

hope this helps
paul :wink:

 

[Philly]

Pete
Rasps come in many different grades-from very coarse to very fine. The rougher rasps are used to remove material quickly-but they leave a pretty rough surface (as you have found out). It might be a good idea to buy a finer toothed rasp to refine the surface (Auriou's come in a wide range) but I prefer to rough out with a rasp and then use a spokeshave and scrapers to refine the surface. And my "favorite", sandpaper. :wink:
Hope this helps
Philly

 

[bugbear]

Auriou's come in a wide range

Yep. All the way from expensive to inconceivably expensive, and covering all the points in between

BugBear[/quote]

 

[Alf]

Don't dismiss the lowly file; you can do alot with a trio of half round files to make up for general coarseness of the average rasp. This is what I used on my spokeshaves, and a drum sander to clean up:



Of course there are rasps and there are rasps... You don't have to get an Auriou, but there's a good chance you'll do better with something other than a set of 4 for a tenner from the nearest Shed.

Cheers, Alf

 

[MikeW]

Any tips on rasping technique gratefully received
...
Is there a particular technique? Do they only work well on close-grained hardwoods? Words from the wise would be welcome!

Hi Pete,

Aurious are very nice rasps--I have many and use them daily.

But we also have and use several of the Nicholson #49 and #50 rasps, which are more reasonably priced.

The brand is probably less important than just obtaining the best ones that fit the budget. What makes the Aurious better is that they are hand punched, which makes for a more random pattern of the teeth. The Nicholson approximate the randomness via machine.

When rasping, a light pressure is all that is required. Some woods spelch--a form of tearout--easier than others. One form of spelching is where wood is literally tore out deeper than the teeth are penetrating. Also, a dull rasp can crush fiber deeper than the teeth penetrate, only to be revealed as one goes deeper. This effect can also occur with dull files: fiber is smashed appearing to be smooth, but in fact the rougher surface is hidden below bent wood fiber only to be revealed when one sands.

We use rasps on nearly every type of wood, but not all wood will allow a coarse rasp to be used without spelching. On woods that spelch easy, use sharp files if you do not have fine rasps.

Again, good rasps come in a full-range of aggressiveness. We use coarse rasps to ones fine enough to lightly sand afterwards on our saw handles. Good rasps and files can often be found used and then restored to near new to better than new performance. In this country, we send our rasps and files to a place called Boggs Tool. But all they do is soak the files and rasps in acid. For what ever reason, the acid attacks the body of a rasp/file faster than the cutting surfaces.

I have tried doing my own with mixed results. Boggs has near perfect results every time. So we send them in. Perhaps someone in the UK knows of a business which does the same? I've paid as little as one-tenth of a US dollar for used rasps, which I in turn have sent to Boggs and for $8 US and postage costs had them come back better than when they were made. Not a bad investment for something that would have cost $100 US new.

I've also had good success buying rasps and rifflers from ePay and sending them in. So that may be a good source of used rasps and files--if you have someone there that can restore them to use.

Files and rasps should be stored so they never touch other metal. In use, they should also not be allowed to either touch each other or other metal bits on one's bench.

OK, I've said enough...time for turning the heat on in the shop.

Take care, Mike
I owe, I owe, so off to work I go...

 

[Derek Cohen (Perth Oz)]

Alf wrote:

Don't dismiss the lowly file

Agreed. I make use of quite inexpensive Nicholson files.

The other rasp type that is useful is a set of Rifflers (in the background).

Regards from Perth

Derek

 

[Alf]

Boggs has near perfect results every time. So we send them in. Perhaps someone in the UK knows of a business which does the same?

Sheesh, I hope no-one's been keeping that to themselves if there is. [-X Although Blightly being Blighty I bet'd cost a bit more... :roll:

Cheers, Alf

 

[AndyBoyd]

I'm a great fan on the Microplane set of rasps (more like cheese graters but very fine ) I got my set from Dick http://www.dick-gmbh.com

The love chairs I'm working on currently plus many other projects have benefited from them, and relatively cheap.

 

[kygaloot]

Some woods spelch

Hey, I learned a new term today. I like that one. Kind of an onamonapia.

Sometimes, when wood spelches, or more accurately, when I am spelching wood, I find that simply changing directions solves the problem. Those rifflin' rasps react to grain too!

 

[kygaloot]

Royally spelched that one. Should be "onomatopoeia"

 

[MikeW]

Some woods spelch

Hey, I learned a new term today. I like that one. Kind of an onamonapia.

Sometimes, when wood spelches, or more accurately, when I am spelching wood, I find that simply changing directions solves the problem. Those rifflin' rasps react to grain too!

Onomatopoeia is the word I think you were going for...maybe, perhaps?

Yes, changing directions works when one sees spelching.

But then again, one more reason to have a wide range of rasps--switch to a finer one before the spelching goes deeper than the desired finish surface.

And the Microplanes do work well on wood, not just the kitchen. And don't discount the firmer Stanley et al versions. They do not flex like the Microplanes do and sometimes that is a benefit. And they are very inexpensive.

Take care, Mike

 

[Pete W]

Thanks all - I knew I'd get some good info

Most of my rasps and files came courtesy of eBay and include at least a couple of good Nicholsons among the no-names. I'm inclined to think my technique is at fault - probably trying to do too much too quickly.

On the other hand, my 50th birthday looms in the not-too-distant future and a couple of Aurious would probably be suitable for such a major milestone... :lol:

 

[ydb1md]

I just received one of these in the mail and it's a gem.

It's smaller than I had envisioned -- about the length of the usual 4in1 -- but that's a good thing. I'm doing more and more rasping on my projects -- as I make more handles, curves and such. I couldn't afford an auriou but for less than the price of one auriou I ordered a Nicholson #49 and this Grobet detail file. The coarse and fine ends work well in combination and it fits nicely in the hand. It gets into pretty tight spaces and does a great job removing the rough teeth marks from the #49. If you like your 4in1 rasp -- I use mine a lot -- you'll love this. Highly recommended.

For more info, check it out here.

 

[MikeW]

Thanks Dave--I had seen these sold by another vendor, and while they are made by Grobet, still wondered about them.

Just might have to give Joel some more money...

Take care, Mike

 

[ydb1md]

I got a good deal on them from Di Legno. They had both the #49 and the detail file on sale.

 

[Philly]

Gave
That looks handy!
Sadly, the Nicholson rasps are not easy to get hold in the UK (this is the point where everyone posts comments to the contrary :lol: ) otherewise I would of recommended them The 49 and 50 seem to be the "go to" rasp combo in all the books I read.
Apologies to all for mentioning the "A" word. It won't happen again.....probably
Cheers
Philly
Who has bought some nice Chinese hand cut rasps off the 'Bay

 

[ydb1md]

Apologies to all for mentioning the "A" word. It won't happen again.....probably
Cheers
Philly

If you're gonna drop the "A" word, at least preface it with a gloat warning. (sheesh) :roll:

Philly,

What sort of saw did you order from Mike? How bad is the shipping?

cheers,
Dave

 

[Pete W]

Sadly, the Nicholson rasps are not easy to get hold in the UK (this is the point where everyone posts comments to the contrary :lol: )

Wouldn't go quite that far, but I did come across some Nicholsons on the Toolshop Direct website when looking for sawfiles t'other day.

Have a rummage around here:
http://www.toolshopdirect.co.uk/handtoo ... _%26_Rasps

I haven't yet been able to decipher the company's descriptions and codes - what the heck are 'horse rasps??) - but there may be 49s and 50s lurking in there somewhere :roll:

 

[ydb1md]

what the heck are 'horse rasps??) :roll:

Horse rasps are used by farriers to profile horses hooves while installing shoes or just grooming the animals.