- Joined
- Nov 8, 2020
- Messages
- 45
I have the slotting head for my milling machine sitting for three or four years now completely unused in the corner. But now I had a part where I couldn't wing it any other way.
The genuine HSS tools for the Deckel slotting head are still available, but really expensive and you have to buy one for every width you want to slot:
So the first thing I had to make was a toolholder where I could use regular square HSS blanks and grind them myself. The keyway I have to cut is of 4mm width in a relatively long, 14mm bore. That means the toolholder must have an even smaller diameter, making it potentially not very stiff. To get the most stiffness, I went with a stepped down geometry like shown in Deckel's technical bulletin:
I started on the lathe with a round bar of 42CrMo4+QT (prehardened 4140):
Then went to the milling machine with the dividing head set up. I first milled the rectangular slotting head mount:
I then stepped down the holder section and predrilled a hole:
I then milled the hole square and handfiled the corner radii away:
The finished toolholder. The square hole is 5mm for 5mm HSS blanks and the stepped down portion has a width of 3,4mm, meaning I can cut 5mm or 4mm keyways with this toolholder.
Since I never used a slotting head, I did a testrun in aluminium:
That went really well, so now the real part, a pulley made out of 42CrMo4+QT with a 14mm bore:
That also went really well. The toolholder was stiff enough and I didn't notice any flex at all. I really started to like working with the slotting head, the operation is quick and straight forward, cutting the keyway maybe took 15 minutes, but I also often paused and double checked the progress.
The genuine HSS tools for the Deckel slotting head are still available, but really expensive and you have to buy one for every width you want to slot:
So the first thing I had to make was a toolholder where I could use regular square HSS blanks and grind them myself. The keyway I have to cut is of 4mm width in a relatively long, 14mm bore. That means the toolholder must have an even smaller diameter, making it potentially not very stiff. To get the most stiffness, I went with a stepped down geometry like shown in Deckel's technical bulletin:
I started on the lathe with a round bar of 42CrMo4+QT (prehardened 4140):
Then went to the milling machine with the dividing head set up. I first milled the rectangular slotting head mount:
I then stepped down the holder section and predrilled a hole:
I then milled the hole square and handfiled the corner radii away:
The finished toolholder. The square hole is 5mm for 5mm HSS blanks and the stepped down portion has a width of 3,4mm, meaning I can cut 5mm or 4mm keyways with this toolholder.
That went really well, so now the real part, a pulley made out of 42CrMo4+QT with a 14mm bore:
That also went really well. The toolholder was stiff enough and I didn't notice any flex at all. I really started to like working with the slotting head, the operation is quick and straight forward, cutting the keyway maybe took 15 minutes, but I also often paused and double checked the progress.
