cutting taper on a shaft

A

almarktool

AzB Silver Member
Silver Member
I have a shaft that i want to cut the taper down on approx .025-.050,
I assume the correct way to do this is to remove the ferrule and cut
the shaft then replace with new tip and ferrule ?
how many cuts should i make ?
I have never done any cue making work before but own my own
machine shop making medical devices holding .0001 tolerences
so i figured it couldn't be that difficult
any tips would be greatly appreciated

www.almarktool.com
 
On a finished shaft go no more than 0.005 a cut. Wait at least 3 weeks between cuts and use live tooling and seal between cuts.
 
That sounds like a bit of a large cut for a finished shaft to me. Are you wanting to reduce the tip diameter? reduce the overall size of the shaft? Different shafts have different tapers, and if you don't want to change the taper profile, you just want to reduce the size, you should take some measurements every inch and cut along the same profile, reducing the cut towards the joint to feather it in.

Kelly
 
almarktool said:
I have a shaft that i want to cut the taper down on approx .025-.050,
I assume the correct way to do this is to remove the ferrule and cut
the shaft then replace with new tip and ferrule ?
how many cuts should i make ?
I have never done any cue making work before but own my own
machine shop making medical devices holding .0001 tolerences
so i figured it couldn't be that difficult
any tips would be greatly appreciated

www.almarktool.com
Click to expand...

If your shaft is not PERFECTLY straight, or perfectly centered, you will cut more off of one side, than the other & ruin the shaft. Since you are taking such a small amount off, I would recommend that , you cut the ferrule & tip down to the finished size( leave a little extra for sanding), then chuck the whole shaft up & sand the wood down to match the ferrule size. Sand from the ferrule towards the joint end. You don't have to sand the whole shaft, only the last 20 inches or so....JER
 
You don't have to remove the ferrule.
But you will need center holes on both ends.
I wouldn't mess passed 16 inches from the tip. You can hand sand that to blend with the new taper.
I wouldn't take more than 20 thousandths off. Then let it sit for 6 weeks if you want to cut again.
 
Kelly_Guy said:
That sounds like a bit of a large cut for a finished shaft to me. Are you wanting to reduce the tip diameter? reduce the overall size of the shaft? Different shafts have different tapers, and if you don't want to change the taper profile, you just want to reduce the size, you should take some measurements every inch and cut along the same profile, reducing the cut towards the joint to feather it in.

Kelly
Click to expand...
Let me elaborate on 0.005 max on the cut. 0.005 dia. which is 0.0025 tool depth. I know what I mean just didn't convey it too well.
 
You need to set up a router or a nice fast spindle with a 2 or 3 wing slot cutter.... then you can take .010 per pass pretty safely. I would wait a day or 2 between cuts.
 

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does that blade cut pretty smooth,Sheldon?we are using the two blade red one from Porter Cable and it is pretty smooth,but always looking for smoother.
 
masonh said:
does that blade cut pretty smooth,Sheldon?we are using the two blade red one from Porter Cable and it is pretty smooth,but always looking for smoother.
Click to expand...
Try Everlast 3-wing slot cutter from Mytoolstore.com.
I have the 1/8 kerf one and it cuts smooooth . Can make a one-inch dowels into cones in three passes. But, you need a rheostat to slow down the router.
Sheldon, what kind of spindle is that? NSK for 10 grand?:eek:
 
masonh said:
does that blade cut pretty smooth,Sheldon?we are using the two blade red one from Porter Cable and it is pretty smooth,but always looking for smoother.
Click to expand...
Yeah, it does a pretty good job. Easy to sharpen, and keep both tips at the same diameter. A slightly slower feed speed is required to get very smooth cuts.
JoeyInCali said:
Sheldon, what kind of spindle is that? NSK for 10 grand?:eek:
Click to expand...
NSK Planet 500. Hits something like 60K RPM at 70 PSI. :D
 
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RocketQ said:
Let me elaborate on 0.005 max on the cut. 0.005 dia. which is 0.0025 tool depth. I know what I mean just didn't convey it too well.
Click to expand...

Hey John. I meant I thought his .050 sounded a bit large, not your .005! :D

Kelly
 
No problem still that is what I meant. .050 is 2 mm so unles he is taking a breaker down that is a bunch. I have never had much luck taking already finished shafts down on the lathe. PIA as far as I am concerned. It is easier to build a new one. Too much junk out there that doesn't have an accurate center in it.
 
RocketQ said:
No problem still that is what I meant. .050 is 2 mm so unles he is taking a breaker down that is a bunch. I have never had much luck taking already finished shafts down on the lathe. PIA as far as I am concerned. It is easier to build a new one. Too much junk out there that doesn't have an accurate center in it.
Click to expand...

I use a saw machine and have no problems what so ever turning down shafts. I don't trust any one Else's centers anyway and always put in new ones. With the saw shaft machine, small warps can be cut away. 1/4 mm or less and I just sand to final size with same tip. More than 1/4 mm and I use the shaft machine with new centers and replace the tip.

Dick
 
RocketQ said:
No problem still that is what I meant. .050 is 2 mm so unles he is taking a breaker down that is a bunch. I have never had much luck taking already finished shafts down on the lathe. PIA as far as I am concerned. It is easier to build a new one. Too much junk out there that doesn't have an accurate center in it.
Click to expand...

.050 is just a little over 1mm. 2mm would be .0788 inches. & it is MUCH easier to take a shaft down, than to make a new one. I did 2 today. I have a chart with increments of 1" It took me about 5 minutes to measure the shaft. Then I centered the shaft (using a dial indicator), in the lathe & cut the ferrule & tip down from 13mm to 12.75mm. Then sanded the shaft to meet the ferrule. Then I cleaned & burnished the shaft. Lastly I sealed the shaft. The whole thing took me about 20 minutes per shaft. I charge $15 for this repair...JER
 
rhncue said:
I use a saw machine and have no problems what so ever turning down shafts. I don't trust any one Else's centers anyway and always put in new ones. With the saw shaft machine, small warps can be cut away. 1/4 mm or less and I just sand to final size with same tip. More than 1/4 mm and I use the shaft machine with new centers and replace the tip.

Dick
Click to expand...
What do you do about the threaded end? I know the chamfer should be the center but not always the case. Do you have a pin with a shoulder to use as a center?
Thanks JER 25.4mm =1" I swear my brain has quit working.
 
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Insert a piece of wood or a cheap joint protector. Put it in your lathe and cut an accurate center in it.
 
RocketQ said:
What do you do about the threaded end? I know the chamfer should be the center but not always the case. Do you have a pin with a shoulder to use as a center?
Thanks JER 25.4mm =1" I swear my brain has quit working.
Click to expand...

Once a new shaft is fitted to a butt or with an old shaft that has been fitted to the butt, I put back in lathe chucking on the deco-ring and running true like I was going to face it. Instead of facing, I use a 60 deg. router bit in the tail-stock chuck and put a slight 60 deg. chamfer on the inset or end of the threads. This now makes the center concentric with the deco-ring so when it turns on a center the deco-ring runs true even if the insert is not centered. Sheldon's way, using a joint protector or such will work also but you need to make a new one for each shaft or at least after every few shafts after re-centering so many times.

Dick
 
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