Farrier's Rasp Knife

by Skrew37

29K41916

Intro: Farrier's Rasp Knife

This is my first instructable, so I'm not sure how to begin... I made a knife from a heavy 14" x 1/4" thick farrier's rasp I bought for $5 at a flea market.

STEP 1: Grinding Down the Teeth

This is after some initial grinding that took forever. Files and rasps are apparently hardened, but not tempered, so they're very hard to work with.

STEP 2: Tempering to Remove Some Hardness

I tempered the file back to make it a little softer and closer to finished knife hardness. This is after two 2-hour tempers in my kitchen oven @ 400 degrees... I was looking for a light straw color, but the blues and plums tell me I may have had it in too long. I turned the oven back to 350F and heated it for another 30 minutes and got the color I was looking for.

STEP 3: Laying Out the Pattern

This patten came from some aspects that I liked from 3 different survival type knives. I think the pros use a dye and scribe the pattern on... I used white spray paint and sharpie, because why not?

STEP 4: Rough Cut

...as the title says.

STEP 5: Cleaned Up a Bit...

Yup. Then I stripped the paint with a spray-on paint stripper and scrubbed with a toothbrush.

STEP 6: Template for the Handle Scales

I had a few ideas, but ultimately went with this. It was some exposed file for the butt or pommel or whatever it's actually called and to drill a lanyard hole through. Also, I started the initial grind on the bevel.

STEP 7: Grind, Grind, Grind, Drill, Heat, Drill, and Swear...

I was aiming for a flat grind, but there was just soo much grinding to do. The best I could do, (which by the way I'm very pleased with) was a 3/4 height convex grind. This will be a great chopper, hopefully.

I found it very difficult to drill through, even with a cobalt drill bit, so I took a propane torch and heated the handle up until it was as red as I could get it and let it air cool, slightly annealing the tang. The hole closest to the blade still wouldn't drill and I was afraid to heat it up more for fear that the heat would creep onto the blade and ruin the temper. So, after a little researching on the dozens of knife forums, I found that a simple carbide-tipped masonry bit would do the trick.

STEP 8: Which Brings Us Back to the Finished Product.

I used curly maple for the scales and 40d nails for the pins. The nails are slightly less than 1/4" diameter and fit perfectly in 1/4" drilled holes. I buffed the blade to almost mirror with a dremel, buffing wheels and compound. The handle was first stained with 2 coats of black Rit clothing dye, then sanded back to reveal the stripes. This also left uneven gray and purple splotches which looked like crap. So in a last ditch effort I applied the only other dye I had which was dark brown leather dye that I use for my sheaths and it saved it. I think it looks like an old rifle stock now. I applied 3 thin coats of boiled linseed oil and 3 coats of paste wax. I don't quite have the finish I'm looking for, so it was suggested I wipe it down with acetone, then apply some Tru-Oil which is actual gun stock finish. For now, I'm overall pretty pleased and I hope you like it too. Thanks!

16 Comments

bobski_horner 8 years ago

on drilling holes n tempered material a trck that was taught to me (after burnng numerous ordinary drills) was this. A normal drill tp is at an angle of 56degrees if I remember . But an old fella told me to flatten the angle of from that to about 20 degrees roughly ,he then got hold of one of my discarded drills changed the angle and the bugger cut through like butter..

Akjamx 8 years ago

We're did u get the arrow from in the picture I lost my arrows and need more those look like the same has mine

Skrew37 8 years ago

https://www.amazon.com/gp/aw/d/B000AM19M6/ref=mobile_oh_details_?ie=UTF8&psc=1

graydog111 8 years ago

Beautiful knife. I really like the rasp pattern on the blade. Great instructable. Now you can publish more. :)

OHELLIFINENO 8 years ago

WRITE LOUDER CANT HEAR OVER ALL THAT GRINDING...WHAT...???I DIDNT HEAR ANY SWEARING...SWEATING MAYBE...VERY VERY NICE KNIFE.!!!

GaryH8 8 years ago

Temper with heat and oil next time.

unclelar 8 years ago

I love the look of your knife,what kind of wood did you use for the handle? That really helped with the finale look of your project.Very nice job! Thank you so much for sharing it with us.By the way,you did an excellent job on your first instructable as well.

Skrew37 8 years ago

I used curly maple scales for the handle. I think it's also called tiger maple.

amberrayh 8 years ago

Wow! This is impressive. What did you cut the rasp with?

Skrew37 8 years ago

Thank you! I used a 4-1/2" angle grinder with cut-off and grinding discs for the bulk, smoothed the edges and did the bevel with a 1" x 30" belt sander (I've just recently upgraded to a 2x42 belt grinder), and the small radii (radiuses?) with a dremel tool with a tungsten carbide cutting bit.

jackowens 8 years ago

Very nice knife! Building knives from old files is great, you know the steel is very hard when you are using a file. Love the way your knife turned out!

tomatoskins 8 years ago

That turned out looking great! Thanks for sharing you process!