Fullers

[Tim Cook 22]

Question for you intelligent blade-smiths.  I have a client wanting a BIG fantasy knife (it is about 20 inches long).  It needs a fuller that is about 3/4 inch wide and about 6 long.  My grinder does not have a large contact wheel and I am not sure how to make it except using a curved piece of wood and a ton of sandpaper.  Is there an easier way?

[Brian Dougherty 1,422]

Forging one in greatly reduces the amount of sandpaper you need to use.  It is still a pretty time consuming process to hand sand one to finish it though.

 

Some people manage to do a good job with a rotary tool or a die grinder.

 

There is also a thread on here somewhere that demonstrates using a hand scraper to do fullers.

 

If you have a friend with a machine shop, a milling machine can be handy for this

[Jaron Martindale 111]

This thread may be useful In Determining If you really need a large Wheel for a 3/4" wide Fuller based on the thickness of the blade.

 

An alternative to using a larger wheel or scraper is to use a small wheel to create a fuller with a much flatter curve by grinding in the shallow initial fuller line and then moving the piece up and down vertically as you grind down the fuller to slowly widen the fuller.  This can still require a piece of wood and lot of sandpaper though, lol!!

[Jeroen Zuiderwijk 322]

With a scraper?

[Doug Lester 409]

Yep.  Basically works on the same principle as a sen except it has a single "tooth" that scrapes the fuller into the blade.

 

Doug

[Alan Longmire 3,881]

Scraping is great for narrow fullers.  In my experience, the wider the fuller, the harder to scrape it in well.  Too much chatter.  I know, that means I need to change the angle of the edge, but it seems I can never get it really smooth if it's wider than about 1/4" / 6.5mm.  I've had great results on wide shallow fullers using a 6" wheel. Wide deep fullers use a 4" or a 2".  That thread Jaron linked is good for figuring out what wheel you need.

 

If you're ambitious, you can also make a cow-mouth chisel and cut it in one go.  You'll still have a lot of cleanup to do, but if you can clamp the blade well enough it's not that difficult to cut a long chip with hammer and chisel.  

[Aiden CC 522]

YMMV, but I’ve forged in a fuller like that and cleaned it up with an angle grinder, rotary tool, and sand paper. It was time consuming but it came out well. You can also rough one in with an angle grinder but it’s a bit challenging and I’ve only done that for for narrower ones (1/4-1/2”).