I found some time to make a little progress on the mill. First, I finished the quill feed worm engagement lever and then I sorted out the quill lever handle and pinion shaft hub.
Drilling the hole in the shift crank and then transferring this to the shaft that engages/disengages the worm took some time and careful planning to ensure that the hole in both parts were perfectly located through the centre. The planning was worth the effort and the selector works as it should.
I did buy a new pinion shaft hub when placed my order with Kondia but I have no means of securing the 6mm detent ball, so I thought I would try to resurrect the old one. You may recall from earlier posts that the original handle was lost and a bolt was welded in its place. I cut off the offending bolt and re-drilled the hole. The I split a piece of copper pipe and inserted that into the bore, so when I welded the hole up, there would be no weld protrusion into the bore. I used the old pinion shaft hub sleeve to hold the pinion shaft hub so I could turn down the diameter and face the hub. The hub has two pins that lock into the sleeve, so this provided the drive. Once done, I drilled and tapped the hole to take the handle. I forgot to take pics of this but I did find two showing the state of the machine when I first got it. You can see the "custom" quill handle and the state of the hub:
The quill lever handle is supplied straight from Kondia but requires a bend in it in order to clear some of the other handles/levers on the head. I wondered why they sent me a straight one and then realized that they couldn't guarantee the final fit with the pinion shaft hub.
Here is the original hub after some TLC with the handle (bent) and attached. The new hub is in the second picture:
Here it is in position with my mate looking on enthusiastically! You can see the worm feed lever as well in this pic:
The hub and handle will get a coat of black paint.
Now just for comparison. Here are 2 pictures of the pinion shaft hub sleeves (old and new) side by side. I still don't know how you can damage one of these so badly
Drilling the hole in the shift crank and then transferring this to the shaft that engages/disengages the worm took some time and careful planning to ensure that the hole in both parts were perfectly located through the centre. The planning was worth the effort and the selector works as it should.
I did buy a new pinion shaft hub when placed my order with Kondia but I have no means of securing the 6mm detent ball, so I thought I would try to resurrect the old one. You may recall from earlier posts that the original handle was lost and a bolt was welded in its place. I cut off the offending bolt and re-drilled the hole. The I split a piece of copper pipe and inserted that into the bore, so when I welded the hole up, there would be no weld protrusion into the bore. I used the old pinion shaft hub sleeve to hold the pinion shaft hub so I could turn down the diameter and face the hub. The hub has two pins that lock into the sleeve, so this provided the drive. Once done, I drilled and tapped the hole to take the handle. I forgot to take pics of this but I did find two showing the state of the machine when I first got it. You can see the "custom" quill handle and the state of the hub:
The quill lever handle is supplied straight from Kondia but requires a bend in it in order to clear some of the other handles/levers on the head. I wondered why they sent me a straight one and then realized that they couldn't guarantee the final fit with the pinion shaft hub.
Here is the original hub after some TLC with the handle (bent) and attached. The new hub is in the second picture:
Here it is in position with my mate looking on enthusiastically! You can see the worm feed lever as well in this pic:
The hub and handle will get a coat of black paint.
Now just for comparison. Here are 2 pictures of the pinion shaft hub sleeves (old and new) side by side. I still don't know how you can damage one of these so badly
Hunting American dentists since 2015.