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Questions on forging rasps & files

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I recently traded some bottle openers for a large bag of horseshoes and 10 Bellota farrier rasps.  Separately I got a large assortment of old files that I plan on making strikers, small knives, basically anything I think people will buy or trade for.  From reading this forum, I see the general recommendation is to start with steel of known quality vs. going with unknown material.  That said, money is tight, I've paid for all my smithing tools and earned extra income by working with what I can get.  I live close to a railyard and the workers there are more than happy to trade me beer & openers for steel they have lying around (and I saved all the emails arranging the initial trade in case it ever comes up).  My big sellers have been gardening tools, spike & wrench bottle openers and the sometimes despised spike knife, which I quench in ice water and don't temper.  So far no complaints on the ability to hold an edge or being too brittle.

 

My questions are:

 

- I've seen mixed comments regarding the quality of steel in the Bellota rasps which I plan on experimenting with first.  Suggested method of heat treating and your experience with them?

 

- Other ideas on what to make that's fun & profitable besides knives with rasps or files?  I saw a post on making rasp spurs, another on a rasp alligator and snakes.  What have been your best sellers?  Pictures please if you have them.

 

- If making a knife out of a rasp or file, do you anneal and grind the teeth or ridges first before forging?  Do you bevel the edge?

 

- Ever since I saw these kitchen knives I've been dying to forge one for myself, for gifts and to sell.  I know many people who love to cook and would pay a reasonable price for a unique knife such as this.  The rasps I have are Bellota Raptors, 14" long by 2 1/4" wide.  How would you cut the file to maximize the number of knives you could get out of it?  I think I'd start with a cardboard template and lay it out on the file with the handle or tail running straight behind the blade.

 

Thanks!

post-34362-0-00616900-1365520741_thumb.j

dc, cool rasp knifes.  I bought a mixed lot of 10 farriers rasps off ebay that I have about worked through.  What I did was get the rasp good and hot and quench in water.  Then taek it over to the anvil and with an inch or so hanging off hit it with the hammer and see it it breaks off.  Some bent and some snapped.  The ones that snapped you can work like its a typical high carbon like 1080.  The other ones can be case hardened and are basically mild steel not good for a knife but plenty good for openers, a tomahawk, etc.  I am not a very good blacksmith but I think this is good information.

You may also find some useful information in the knife makin lessons on  this site....

  • Author

Thanks Momatt. When you forged the rasps did you do it with the teeth on, or anneal it and grind them off first?  I'll check out the knife making lessons.

My best seller here in New Mexico is rasptlesnakes using bottle caps with a punched hole to slide onto a drawn down "tail" for "rattles"    They are loose and so sound a lot like the real ones when shook correctly.  Helps to anneal the tale end so you can curl it over to hold them on *cold*.

 

I also made a nice kindling hatched from a rasp by bending it double around a hammer handle mandrel and forge welding the overlap.  Left the teeth on for both items

  • Author

Rasptlesnakes...I love it!  Those would go over well where I live also.  Would you have any photos of the snakes or hatchet?  Do you anneal the files before you forge them?  I saw posts where it was recommended, but annealing before forging doesn't make sense to me unless you are doing it to soften the metal to shape or grind.

 

What color are you forging at?  Less than a dull red and it risks cracking, though more carbon > chance of burning it up in the forge.

I've always been told that farrier rasps were case hardened A36 (mild steel) but I think it depends on what brand your using. Just try a small piece of what you have, worse case, you'll have to make snakes and gators instead of knives.

  • Author

I'll post an update when I've had a chance to experiment with the Bellota rasps and what I forge from them.  They're going to have to wait a little longer before I can do something with them as I know have several new orders from people w/ cash in hand.  I'm going to set at least one aside for hot rasping.

 

I did find this thread which answers my question regarding annealing and removing the teeth.  http://www.iforgeiron.com/topic/1975-kinives-from-files-advice/?hl=%2Brasp+%2Bfiles#entry15303 

 

It would make sense if making a knife to anneal it first and grind off some of the teeth, whereas if doing something else with it I'm not so sure.

  • Author

Test results look promising, I'll definitely try forging some knives with the Bellota rasps.  Heated the end of one to non-magnetic and then quenched it in water.  Broke clean with one hit with an inch hanging off the anvil.  The picture quality isn't very good, but hopefully you can see that the grain appears small & compact.

  • Author

Picture failed to upload, trying again.

post-34362-0-20927100-1365649580_thumb.j

  • Author

Digging thru the archives on rasp files & knife making, here are some that I've found.  This might help someone or myself later not have to do so much searching.

 

Info regarding how to make a rasp snake, various brands & hardening tests

http://forums.dfoggknives.com/index.php?showtopic=4295&page=2

 

Ways to harden & temper

http://www.iforgeiron.com/topic/27222-farrier-rasp-steel-type/

 

Richard Hanson Knife Making

http://www.iforgeiron.com/topic/30540-richard-hanson-knife-making/?hl=%2Brasp+%2Bfiles

 

Kukri Rasp Knife

http://www.iforgeiron.com/topic/10294-kukri-with-feathers-8/?hl=%2Brasp+%2Bfiles#entry101839

 

Summarization of steps involved

http://www.iforgeiron.com/topic/9704-file-knife/?hl=%2Brasp+%2Bfiles#entry95607

 

How to draw file

http://www.iforgeiron.com/topic/6213-wow-draw-filing/?hl=+rasp%20+files

 

Annealing, soaking & the teeth

http://www.iforgeiron.com/topic/1975-kinives-from-files-advice/?hl=%2Brasp+%2Bfiles#entry15303

 

Files & filing

http://www.iforgeiron.com/topic/23326-files-filing-primer/?hl=rasp

Spark test the inner part of the rasp.

  • Author

Any grinding I do, I plan on annealing first though would leave on enough to show that it was a rasp in former life. 

 

Interesting thought on folding the teeth back down.  I have enough of these, so when I have time I can experiment.  Good idea on spark testing the center of the rasp, I'll see what that shows.

Test results look promising, I'll definitely try forging some knives with the Bellota rasps.  Heated the end of one to non-magnetic and then quenched it in water.  Broke clean with one hit with an inch hanging off the anvil.  The picture quality isn't very good, but hopefully you can see that the grain appears small & compact.

 

Not sure why you felt you had to heat and quench ? 

 

If you had put it in the vice covered it in a cloth and hit it, if it bent, it was case hardened, if it broke, then it would be a higher carbon steel fit for heat treating, most files are quite brittle and so snap quite easily.

  • Author

I'm learning, this is new to me.   What I read on this forum, as well as other sites recommends heating to non-magnetic, quenching in water and then testing it on the anvil to see if it gets brittle hard and breaks.  I just tried it without heating & quenching and the rasp bends.  Then I tried a couple of old files as you suggest, one being a Heller and they all snapped as you said.  I noticed on those files that you can't really see the grain, it looked more clay or glass like.

 

I also did a spark test on the inside of the breaks for both rasps & files.  The Bellota rasps spark the same inside the break as outside, and noticeably more than a HC railroad spike, but less than the Heller or other old file I tested.  I can't see any demarcation on the rasp that would indicate it was case hardened though. 

  • Author

Stefflus, did you forge the Save Edges into knives?  If so did they hold their edge well and what process did you use to heat treat them?  I plan on forging a knife out of the Bellotas and then giving it to a friend who hog hunts to test it for me.  If it can hold it's edge while field dressing a hog it can handle about anything.

 

I guess next I should see if they harden in oil.  When you say fully harden, how do you know, compare spark test, inner grain, etc?  I don't know much at this point about HT & hardness, but it is obvious that there are different degrees of hardness and how much you temper afterwards will depend on the type of steel, how it was hardened and how the tool is going to be used.  Which using steel of a known composition makes sense unless you are going to be able to get a steady supply of a material and can take the time to experiment with it.

 

Side note:

 

Seems like the forum is unable to post additional replies that would normally go to the next page, or you just can't navigate to the next page if it's there.  If that's the case then this thread is dead until the problem with the forum is resolved.

I am suprised that your rasps bent when not heated and quenched. Did you try the part of the rasp that was hard or only the tang which has been drawn back considerably, so that a screw on handle will bite into it?

  • Author

For the rasps I only tried the tang w/o heat or quench, whereas the old files I tested the opposite end.  Good catch, I didn't consider that being a factor, but it could be.  It'd be interesting to test.

  • Author

For the rasps I only tried the tang w/o heat or quench, whereas the old files I tested the opposite end.  Good catch, I didn't consider that being a factor, but it could be.  It'd be interesting to test.

  • Author

For the rasps I only tried the tang both with heat & quench and without.  Whereas the old files I tested the opposite end of the file.  Good catch, I didn't consider that being a factor, but it could be.  It'd be interesting to test.

  • Author

For the rasps I only tried the tang both with heat & quench and without.  The old files I tested the working end of the file.  Good catch, I didn't consider that being a factor.  It'd be interesting to test.

I leave some of the marks in the steel from the rasps and they come out very well just have to find the right quench medium for your perticular steel

I leave some of the marks in the steel from the rasps and they come out very well just have to find the right quench medium for your perticular steel

  • Author

Thanks for all the responses & information.  I'll post some pics when I've had a chance to forge them into something.

  • 2 weeks later...

 

John B:  This might hold true for files, but I was given 10 Save Edge and 2 Mercury farriers rasps. When hitting in a vice, the Mercuries broke and the Save Edges bent.
However, when heated and quenched, the Save Edges broke. It actually fully hardened in oil. Maybe they just harden the teeth at the factory with a blast of air or something?

 
With regard to this "Case Hardening" of files, I think these are not so much case hardened, but are actually induction hardened which would account for their behaviour when I recently came across some that bent amongst others that were brittle right through.

I just raised them to hardening temperature and quenched in water, placed in vise and whacked, nice clean break. Will have to try forging hardening and tempering when next I get a chance.

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