Kondia FV-1 Head disassembly

[Mayhem]

(05-01-2015, 07:13 PM)stevec Wrote: C'mon Ken, "dirty" you outa know that ain't Darren's style

How is this for dirty Steve?

I got tired of using old car radiator hose and wooden wedges to secure long lengths of stock on my lathe, so I turned up a spider for the back of the spindle.  The body is about 96mm ø with a 68mm through bore.  The bucket in the foreground is predominately from large diameter drilling before boring.

   
   
   

I'm very happy with the finish, despite not having a power feed on this lathe.  Tomorrow I'll poke the necessary holes in it.

My next project was the drawbars for my Kondia mill and I only managed to get one machined.  I had a lot of trouble turning the 4140 due to long stringy chips. I tried three different inserts and a range of (manual) feeds and DOC's.  I was getting very nice finishes at 1600 rpm but couldn't break the chips.  Instead, I ended up with a birds nest before I had made a full length cut, more often than not.  I tried a Tungaloy CCMT09T304-24 T725X, a Walter CCGT 09T304-PF5 WPP20 and an Iscar CCMT09T304-SM IC907.  I found the Iscar insert performed better with a 1.0mm DOC and a really fast feed.  However, it certainly wasn't a clear winner and I would have probably gotten the same results with either of the others.  I often had to manually break the chips.

My design incorporates a 26 x 13 thrust bearing, with one (well two-thirds) being used for each drawbar.  Being a 26 x 13 bearing, one of the races and the bearing assembly itself have the smaller 12mm ID.  So, the 12.7mm ground 4140 round was turned down to 12mm and the bearing race and bearing assembly pressed on.  Once these were on, the hex drive was fitted (the hex will be milled tomorrow).  The 13mm ID bearing race is affixed to a carrier (highlighted below) that is fitted into the top of the spindle, thus completing the thrust bearing assembly regardless of which drawbar is in use.  

   

Next it was flipped over and turned down for the minor diameter for a M12x1.75 thread.  Once this was done, the end was single point threaded.

   

The finished assembly: