- Joined
- Aug 22, 2012
- Messages
- 4,121
Had a good day today, made a Die holder.
I had a MT2 dead centre with a chewed up point so I cut the conical part off.
Using a MT3 to MT2 adapter in the spindle I faced the end, I thought it would have been harder than it was.
Drilled it out at 12mm by 50mm deep.
Turned down a 50mm section of 20mm bar to an interference fit and pressed it in with locktight.
Replaced the MT2 into the adapter and centre drilled the end of the bar to to turn it between centres down to 15mm using a shear bit to get a fine finish.
The die holder is a chunk of cast aluminium turned down, bored to 15mm to slide on the shaft.
I had to bore from each end as my boring tool wasnt long enough and much to my surprise the bores met if not exactly then not enough out to notice. It slides on the shaft with no play.
A 5mm grub screw holds the die in place to prevent it from slipping.
In action making the 6mm thread for the tommy bar.
You will notice that the aluminium is covered in little black dots - hydrogen porosity unfortunately.
As the casting is not the strongest of materials due to the porosity I drilled through the casting and screwed the tommy bar to the opposite side so as not to strain the thread.
I had a MT2 dead centre with a chewed up point so I cut the conical part off.
Using a MT3 to MT2 adapter in the spindle I faced the end, I thought it would have been harder than it was.
Drilled it out at 12mm by 50mm deep.
Turned down a 50mm section of 20mm bar to an interference fit and pressed it in with locktight.
Replaced the MT2 into the adapter and centre drilled the end of the bar to to turn it between centres down to 15mm using a shear bit to get a fine finish.
The die holder is a chunk of cast aluminium turned down, bored to 15mm to slide on the shaft.
I had to bore from each end as my boring tool wasnt long enough and much to my surprise the bores met if not exactly then not enough out to notice. It slides on the shaft with no play.
A 5mm grub screw holds the die in place to prevent it from slipping.
In action making the 6mm thread for the tommy bar.
You will notice that the aluminium is covered in little black dots - hydrogen porosity unfortunately.
As the casting is not the strongest of materials due to the porosity I drilled through the casting and screwed the tommy bar to the opposite side so as not to strain the thread.
That'll teach me to assume a problem part is the same part that's been a problem before! Nevermind, I'll put turn the radio up for the drive tonight and order another one from Rockauto ($16 with shipping!).
