46 Attachment(s)
Lathe drive center and soldering pick
Hi again
A while back I've made this drive center for turning wood blanks on my mini lathe.
Attachment 26858
The idea of making this tool was taken from the following picture I found on the web while I was searching for buying an MT3 drive center.
Attachment 26859
This drive center threads into the spindle of the Unimat DB/SL lathe.
I've made three videos showing the built and use. You will find each video after a series of photos.
I used three different steels, Calmax® and Sverker® 21 tool steels for the body and the prongs and free cutting steel for the threaded adapters’
Attachment 26814
Attachment 26815
Total length 71.5mm, shaft diameter 14mm
The diameter of the adapters are 34.8mm and 18.8mm
Attachment 26816 Attachment 26817 Attachment 26818 Attachment 26819
Attachment 26820
Total hardening to 58 HRC for the body and the prongs, surface hardening by nitriding for the adapters
Attachment 26821 Attachment 26822
400G sandpaper for finishing
Attachment 26823
The distances between the points are 26.50mm for the large adapter and 12.50mm for the small
Attachment 26824 Attachment 26825 Attachment 26826 Attachment 26827
https://www.youtube.com/watch?v=Vd3fX8OBCKg
I tested the drive center by making a soldering pick. For those of you that don't know, this tool is useful while soldering semi precious or precious metals. It helps in positioning solder pieces as well as it guides the melted solder to the metal surfaces.
This is my old soldering pick (I use it occasionally now)
Attachment 26828 Attachment 26829
For making the new one, I used a 3/4 x 3/4 x 4.4” piece of African Blackwood, a piece of brass 18mm x 38mm and a 3/32 x 7” tungsten rod
Attachment 26830
The ‘nose’ of the tool was made first
Attachment 26831 Attachment 26832
Then, was the time to test my drive center
Attachment 26833 Attachment 26834 Attachment 26835 Attachment 26836
I made a thumb screw using a 6mm brass rod and a 3mm set screw
Attachment 26837 Attachment 26838 Attachment 26839
https://www.youtube.com/watch?v=q7mQWfEMxaQ
For expanding the abilities of the tool, I made two more adapters
Attachment 26840
The diameters are 34.8mm and 24mm
However I came across a problem that I should have thought of in the first place. The problem was that the driving adapter was over-tightened from the cutting force while turning and it was very difficult to un-tighten it from the threaded shaft; I fixed the problem by copying an easy to make wrench I found on the web.
First I made a hole at the side of each adapter
Attachment 26841 Attachment 26842 Attachment 26843
Now, both small and larger adapters have the same body diameter with each other, so with two wrenches the job was done
Attachment 26844
For making the prongs for the new adapters I used the shanks from two 4.0mm HSS drills
Attachment 26845
Both adapters were heat treated
Attachment 26846
The distances between the points are 16.50mm for the small adapter and 20mm for the large
Attachment 26847 Attachment 26848
Now to be able to turn wood between centers, I bought an MT3 soft blank arbor and converted it to drive center
Attachment 26849 Attachment 26850 Attachment 26851
The center prong was made using the remaining piece of the 4mm drill shank
Attachment 26852
Attachment 26853 Attachment 26854 Attachment 26855 Attachment 26856
The optimal turning length with the live center in the tailstock is 270mm, but it can be increased to 290mm if I use a dead center
Attachment 26857
https://www.youtube.com/watch?v=oLS64P8M714
All the best
Dimitris
