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DSEL74
17th April 2018, 08:45 PM
https://uploads.tapatalk-cdn.com/20180417/500a26af64877bbe633927fc3f90798c.jpg
https://uploads.tapatalk-cdn.com/20180417/713e743118ba4b93a9326b948c235ab8.jpg

I have the Tomahawk eye mandrel as shown. I can import the 19” long handles as shown but postage is more than the handles. The handles have an even taper from end to end.

I’m wondering if it is possible to turn these on a standard wood lathe or is is a job for a copy lathe?

BobL
17th April 2018, 09:34 PM
These are normally done with a copy lathe but a standard WW lathe will get you most of the way there.

Start by by rough turning the shaft about a main centre, and then two opposite off centres to produce what I call a double pointed "Eye" profile.
Then set up back on the main centre to take off the points of the "Eye" down to about 3/4's of the way to the end of the handle.
The use a spoke shave to take one point of the eye off up near the end of the handle.
I have done a couple like this and they are a PITA and would only do them if I no more than 2-3 to do

DSEL74
17th April 2018, 09:38 PM
These are normally done with a copy lathe but a standard WW lathe will get you most of the way there.

Start by by rough turning the shaft about a main centre, and then two opposite off centres to produce what I call a double pointed "Eye" profile.
Then set up back on the main centre to take off the points of the "Eye" down to about 3/4's of the way to the end of the handle.
The use a spoke shave to take one point of the eye off up near the end of the handle.
I have done a couple like this and they are a PITA and would only do them if I no more than 2-3 to do
Hmmmm sounds complicated.

KBs PensNmore
18th April 2018, 12:48 AM
Using a copy lathe would be the easiest, not something like Symtec Copy Lathe, but one that rotates the sample at the same speed as the turning. It has a follower that has similar to arbortec cutter attached. Have attached a youtube clip for you; https://www.youtube.com/watch?v=JfamgMe3DTE
You might be lucky to find a member on here that has one.
Kryn

Mobyturns
18th April 2018, 07:48 AM
A very similar cross sectional profile can be replicated on a standard wood lathe using three centres as BobL has described. However the profile shown is not three simple curves, it is a mirrored complex curve quite similar to the curves used in road design - a spiral transition from a straight into a circular curve..

This is how they are traditionally made -

https://www.youtube.com/watch?v=GZ8DW7JBQvE

https://www.youtube.com/watch?v=X5dALI0QngE

ps, in case you are wondering a spiral transition is used in road design so that passengers sense a gradual increase in centrifugal force when changing direction from a straight into a circular curve :cool: , and to greatly minimize the potential for vehicles to skid off the road. :D

BobL
18th April 2018, 08:05 AM
Hmmmm sounds complicated.

Not that complicated but it's a PITA if you have to make more than a few

BTW The only reason I suggested my method was possible was because the's handle is (apart from the section end) inherently straight. The method I suggested will not work on no straight shaped handles like axes.

DSEL74
18th April 2018, 08:31 AM
Mobyturns that is a different style of axe handle in your video. And KB’s video is way different.

The tomahawk is the same tear drop profile end to end just straight taper of same to a smaller version. The head slides in from the small end and wedges it self at the top. Similar to a pick and sow hoes.


KB,
I think there are two members with copy lathes. I remember a discussion on them a while back. One maybe Rob (Auscab). I have no idea if the discussed machines are even set up and running.

BobL
18th April 2018, 08:56 AM
Mobyturns that is a different style of axe handle in your video. And KB’s video is way different. .

Sure but the same machine can make your tomahawk handles as well

DSEL74
18th April 2018, 08:57 AM
Sure but the same machine can make your tomahawk handles as well

Oh yes I’m sure it could.