Milling blade bevels with tapered end mills?

A

AWGunS

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Sep 16, 2006
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I have seen a post or two about milling blade bevels. One I remember reading tilted the blade on 3 degrees with an angle vise, milling, then 3 degrees the other way for the opposite side bevel. Easy enough if you have an angle vise, or the time to make a jig. But has anyone tried using a tapered end mill? They are available with 3 degrees per side taper, and other than making up something to keep against the off side while milling to keep the blade from deflecting, it seems doable, without having to purchase a special vise or angle plate.

a 1/4 EM runs about $25. I may just make a little investment and experiment.

Curious as to what you guys think.

A Smith
 
In the real world I run a Bridgeport Mill every day and in my spare time I make an occasional knife with a belt sander. I am sure I can grind a blade ready for HT faster and better looking than I could get the mill set up properly to rough mill a blade and then have to use the grinder to blend the mill cuts into a useable blade. Sorry about not being more encouraging.
 
This may work on a knife like a tanto where all the bevels are straight, but how do you plan to follow the curve of a drop point knife? You will also get some chatter marks in the blade which you will have to get out.
 
but how do you plan to follow the curve of a drop point knife?
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CNC would do this pretty easy. If you designed the profile in CAD...then you would have the grind line tool path. I would hold the blade partially in a vice with edge up.

In the CAM softeware , put the edge profile in the X-Z plane to generate the tool path. Adjust the blade edge thickness with cutter comp offset.


Yes...the more I think about it.....the easier I think it would be for someone with CNC and CAD CAM.

The knife would have a Flat bevel...which would be easy to finish by hand, with a Rotary platen, or a RO-sander.

-Rob
 
I'm curious, why would the bevel have to be flat? Using a small diameter end mill you could easily set up a contour for different hollow and convex grinds. We have a cnc router at my school that you can make things like that. Also, I would lay the knife on its side and do one side at a time.
 
I have a 1" Delta bench sander. I have tried to do bevels on scrap material, but I am not at all happy with my results.

I am not to the point of spending upwards of $600+ on a belt grinder. I have a CNC mill available at work, and if I can turn out flat grinds (or mills if you will) on that, it will save my hands and fingers the pain of roughing out with files. I realize I will have to take out the tool marks one way or the other, but it would still save a huge amount of time.

I am going to give it a shot. If I am not happy, or successful for that matter, I'll think about my next move.

A Smith
 
I read an article in a recent tactical knives mag about a knife. I think its called an airlock. This knife is made entirely from CNC milling. The blade bevels are also cut by CNC.

It seems viable, but i think you would probably be better off just doing it on a belt grinder.
 
AWGunS said:
I have a 1" Delta bench sander. I have tried to do bevels on scrap material, but I am not at all happy with my results.

I am not to the point of spending upwards of $600+ on a belt grinder. I have a CNC mill available at work, and if I can turn out flat grinds (or mills if you will) on that, it will save my hands and fingers the pain of roughing out with files. I realize I will have to take out the tool marks one way or the other, but it would still save a huge amount of time.

I am going to give it a shot. If I am not happy, or successful for that matter, I'll think about my next move.

A Smith
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I hav the 1x42 delta and with a lot of practice i hav goten decent bevels
 
AWGunS said:
I have a 1" Delta bench sander. I have tried to do bevels on scrap material, but I am not at all happy with my results.
Click to expand...

There are a couple things that could cause your unhappyness that occur immediately to me:

- Have you been using good belts? Especially in a 1x30 or 1x42, Alum. Ox. belts will just vanish without doing much work. Try a good ceramic/zirconium/SiC belt and see if it helps at all .

- You may just need more practice. Nobody said knifemaking was easy. If it was, all these great custom makers around here would be out of a job!

I know at least one full-time maker (on this forum) who until VERY recently didn't have anything but a Delta 1x42 for a grinder, and he turned out some marvelous work with it.

I'm not trying to bash your idea at all, I'm just thinking that in the long run, milling your bevels may take more time and be more work for you. Even on a 1x42 I'd bet a lot of folks here could rough grind bevels in 5-15 minutes. I could probably only manage to screw up a milling setup a couple times in that amount of time... :)

-d
 
who me:D
the milling thing was something i was thinking about tring to do a while back cause of the kabar projects i was working on
i thought that since i was already milling the fullers why not mill the bevels
gave up on it real quickly as my mini mill just is not goingto do it

on the 1x42 thing that are some helpfull things abut the little grinder one it makes you go slower and you find that you get belt edge grooves fast so it sorta makes you a better grinder least i have thought so now that im up to a kmg
any how i might have to put up a little if using a 1x42 tip sheet some time
 
I think if a CNC is used to make the bevels, the entire knife should be cut with it. The tool marks are attractive if the programmer is good and sharp tools are used. Ceramic bead blast and/or tumbling finishes would be cool. Otherwise belly up to the grinder like the rest of us poor saps.
 
Don - do you have any pics to show us how? and what you use?
 
I know practice makes perfect (or something like that), so more time on the belt grinder will certainly help. I will have new quality belts soon, and that might make a difference.

I am going to pick up a tapered endmill this week. Might take me a week or two to get to using it (on scrap). If it doesn't work out, then I'll think more of getting a good grinder.

We will see. Thanks for the comments and opinions-good, bad or otherwise. Thats what I came to this board for:D . I will post my experience.

A Smith
 
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