DIY Arrow Cut Off Saw

Tuck

New member
Maybe a daft question... Has anyone tried spinning the shafts up against an abrasive cutting edge?

Mount the shaft in a normal drill, and present it to a fixed cutting edge. It sounds so obvious (though I can think of some complications) that I'm kind of surprised I can't find anything mentioning it as an approach.
The main issue is consistant and accurate shaft length, with a drill you are driving the arrow from the end you want as a measuring base.
 

wingate_52

New member
I tried truing up one broken shaft on a stationary belt sander with a fine 240 belt. The end of the arrow just crumbled away. I have used a Best arrow saw, that was great. Now I use my own with plenty of backup diamond discs. The larger diameter the better.
 

Rik

Supporter
Supporter
The main issue is consistant and accurate shaft length, with a drill you are driving the arrow from the end you want as a measuring base.
That's kind of the point. Fixing the end in place so that you get a consistent length. I'm assuming here that you'd clamp the drill in place and measure from there to the cutting edge. I'm also assuming that you'd set things up so that a tiny pressure on the shaft would move it into the cutting edge. Not sure about rollers. Might not be necessary. The cutting edge could be a normal cutting disc clamped in place...
 

chuffalump

Well-known member
A fixed abrasive edge would wear at the cutting point whilst a spinning disc spreads the wear around it's circumference. I don't think you'd get the quality.

Maybe a fixed hardened steel cutter from a lathe might do it. Definitely need support for the shaft though.
 

carl7

New member
Since I have the metal lathe setup, I'm thinking of a way to mount a rotary cutter on the tool rest with microfeed. The tailstop can be used to gauge how much shaft is to be cut off.

Also have to make a adapter for the 3 jaw chuck to hold the arrow shaft gently.

Carl
 

geoffretired

Supporter
Supporter
How about putting the cutter in the chuck and mount the shaft in the tool rest? I have thought of that with my own lathe, but it is far too short. If it was convenient to use it that way, I would probably make a way to hold the round shaft in the tool rest, in such a way that the shaft wasn't damaged.
To hold the shaft gently in your chuck, if you go that way,a round bar of delrin ( or similar) with a hole through the centre, done on the lathe, that is a tight push fit on the shaft will do the job.
I use a block of wood in my jig with holes drilled through for the shafts I use. Most of the holes are pretty standard drill bit sizes( some metric, some imperial). The cutting action does not put much strain on the shaft, so a push fit is good enough to hold the shaft in place during the cutting.
 

Tuck

New member
That's kind of the point. Fixing the end in place so that you get a consistent length. I'm assuming here that you'd clamp the drill in place and measure from there to the cutting edge. I'm also assuming that you'd set things up so that a tiny pressure on the shaft would move it into the cutting edge. Not sure about rollers. Might not be necessary. The cutting edge could be a normal cutting disc clamped in place...
Rotating a 30 inch arrow at say 10,000 rpm is going to need serious support and protective covers, how to grip the arrow end with different sizes and nocks would be a real issue. The arrow to motor connection would need to resist the cutting forces. Just too complex and dangerous.
 

carl7

New member
How about putting the cutter in the chuck and mount the shaft in the tool rest? I have thought of that with my own lathe, but it is far too short. If it was convenient to use it that way, I would probably make a way to hold the round shaft in the tool rest, in such a way that the shaft wasn't damaged.
To hold the shaft gently in your chuck, if you go that way,a round bar of delrin ( or similar) with a hole through the centre, done on the lathe, that is a tight push fit on the shaft will do the job.
I use a block of wood in my jig with holes drilled through for the shafts I use. Most of the holes are pretty standard drill bit sizes( some metric, some imperial). The cutting action does not put much strain on the shaft, so a push fit is good enough to hold the shaft in place during the cutting.
Hey thanks Geoff for the tips, I hadn't thought of that, and that would free me from trying to use the Dremel with it's limited ability for cutoff disks. I have lots of 3" cutoff disks but won't fit the Dremel.

On second thought, I have collet chucks, that might do the arrow holding job too. Maybe wrap tape on the arrow to prevent any marring.

Amazing the capabilities this old (1936) lathe has opened up.

Carl
 

wingate_52

New member
Don't rotate the arrow in the lathe. use the lathe to drive the cutting disk. If the lathe is not long enough, make an extension. You don't hold the arrow in the tailstock, but hold the arrow parallel to the bed, with the "tail end" of the arrow offset from the centre of the lathe. You don't need rollers to support the arrow, just a smooth shelf to the arrow side of the cut off wheel, which needs to be thin, and driven at 25,000 rpm, a bit fast for a lathe or electric drill. Woodwork router, sewing machine motor drive, pulleys from a motor? Buy a "dremel", Aldi/Lidl have decent ones, and make up a cut off saw. There is plenty of inspiration on the web, but do be careful and wear goggles/facemask plus dustmask for the carbon dust. Even though my cut-off saw looks simple, it is well engineered in wood and the Dremel is a good tool, as is the inexpensive ebay sourced diamond disc.
http://s130.photobucket.com/user/wingate_52/media/Arrow Saw/P1020820_zps1d115333.jpg.html?sort=3&o=5
 

Tuck

New member
Don't rotate the arrow in the lathe. use the lathe to drive the cutting disk. If the lathe is not long enough, make an extension. You don't hold the arrow in the tailstock, but hold the arrow parallel to the bed, with the "tail end" of the arrow offset from the centre of the lathe. You don't need rollers to support the arrow, just a smooth shelf to the arrow side of the cut off wheel, which needs to be thin, and driven at 25,000 rpm, a bit fast for a lathe or electric drill. Woodwork router, sewing machine motor drive, pulleys from a motor? Buy a "dremel", Aldi/Lidl have decent ones, and make up a cut off saw. There is plenty of inspiration on the web, but do be careful and wear goggles/facemask plus dustmask for the carbon dust. Even though my cut-off saw looks simple, it is well engineered in wood and the Dremel is a good tool, as is the inexpensive ebay sourced diamond disc.
http://s130.photobucket.com/user/wingate_52/media/Arrow Saw/P1020820_zps1d115333.jpg.html?sort=3&o=5
Sounds just like a standard arrow saw configuration.......


Eat, Drink, Shoot, Enjoy.
 

Rik

Supporter
Supporter
Rotating a 30 inch arrow at say 10,000 rpm is going to need serious support and protective covers, how to grip the arrow end with different sizes and nocks would be a real issue. The arrow to motor connection would need to resist the cutting forces. Just too complex and dangerous.
Holding the arrow might be simple enough. Tighten the chuck on a Better nock adapter. The nocks just snap into that, centred and secure.

All speculation, mind you. I guess the only way to test this would be to try it out... I've got some dead shafts, somewhere... Just need that missing piece. The "round tuit".

Damn autocorrect... Morphing nock to mock, I can kind of understand, but "snaps" to "emails"? What is this? My phone trying to tell me I'm a Luddite...?
 
Last edited:

Rik

Supporter
Supporter
Okay, scratch the nock adapter idea... (Unless you want the shaft doing a "fan" impression...).

On the other hand, placing the shaft itself in the chuck seems to produce a stable rotation.

And it's possible to bend the shaft out of the straight line without disturbing that situation (if anything it seems to add to the stability).
Now if I could just find where I put those cutting discs...
 

carl7

New member
Finally a productive day. Mounted the string jig posts on the square tubing, rock solid. Turned a 3/8" arbor for some 4" cutoff disks I had, mounted it on the lathe, (thanks Geoff and wingate_52) and it does a great cutting job on some throw away arrows. Mounted a V-Block on the lathe turret to hold the arrow. Next will turn a 1/4" arbor for the die grinder which spins a lot faster than the lathe, around 15000 rpm. I'll look for some smaller cut off disks, around 2".

Even got in some shooting practice.

Carl
 

carl7

New member
Turned a 3/8" arbor for some 4" cutoff disks I had, mounted it on the lathe, (thanks Geoff and wingate_52) Mounted a V-Block on the lathe turret to hold the arrow.

Update: Turns out the 4" cutoff disks were too course, while the cut was usable, it left scratches on the cut surface. Found some Dremel reinforced 1-1/4' cut off disks, (much stronger than the very thin Dremel disks) so chucked that in a small 1/4" drill chuck, (the Dremel shaft is 1/8") put the small chuck in the large lathe chuck...perfect!

Cuts the arrow shafts clean as a "Dremel" tool. The V-block setup on the lathe turret works great and I can use the tailstock as a length stop gauge.

Carl
All in all, a successful day for a change.
 
Top