Hello everybody I hope all is well. I have a question about the tailstock. I have the central machinery (harbor freight) 13x40 heavy lathe, the tailstock quill has a measuring scale engraved on it, the problem is after I move the quill out to a little over an inch on the scale and tool ,ie center, or chuck seems to lock in place. When I retract the quill it will not reach 0(zero) without ejecting the tool. I think this is incorrect, the manual has no info and I have learned to work around it.. I feel it should not eject the tool til after it reaches zero on the scale. Is there some way to adjust this? any help is appreciated. KEEP MAKING THE CHIPS, SOMEONE WILL SWEEP UP LATER!!
Tailstock quill adjustment?
- Thread starter wfSR
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BaronJ
Grumpy Old Git.
Oh ! I thought you might come round and sweep up for me !
Seriously though. On my Myford it will eject some tools early and some later.
Like yours it has a scale engraved on the quill but its only a guide. If you want an accurate depth measurement then you need to fit a device to do that. On mine I used an electronic tyre tread depth gauge. Picture below.
I used magnets to both attach it to the tailstock body and to attach the stylus to the perspex plate with a steel slug in it.
BaronJ
Grumpy Old Git.
Hi wfSR,
Just seen that you are new here, so let me be the first to welcome you to the HMEM forums. I'm sure that others will give you a warm welcome as well.
Have fun.
Just seen that you are new here, so let me be the first to welcome you to the HMEM forums. I'm sure that others will give you a warm welcome as well.
Have fun.
Thank you for the welcome and the info. Got a reply from my other club and was advised that there is an adjustment of the "ejecter bud" . I am to undo the dial and there is a slotted plug inside....you turn this in or out to set the depth . ok, now if I can figure out how to remove the dial, can't find a set screw...unsure of how the handle is own.....guess I need to call the Chinese . hahaha
This is perfectly normal operation of a quill.
Think about how the quill works. There is a leadscrew that runs down the center of the quill to run it in and out. This is what pushes the taper out. Now every taper is a bit different these the leadscrew has to be setup for a range of tapers, especially those with and without driving tangs. In otherwords the same mechanism that pushes out your dead center. Also pushes out the morse taper drill bit. You should be able to see this buy ejecting a dead center followed by a drill bit with a driving tang built in.
Ultimately there is no way to fire this as the lathe is designed. Simply put you need to accommodate anything with a morse taper that might get stuck in the quill.
There are other approaches, for example tools or centers with front extraction capability. That is a center that can have a nut screwed onto it to eject it from the morse taper. You could also build a custom quill that can eject a morse taper with a tang in the same way a drill press does. Of course the question is why would you do this when lathes have worked like this for centuries now.
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Think about how the quill works. There is a leadscrew that runs down the center of the quill to run it in and out. This is what pushes the taper out. Now every taper is a bit different these the leadscrew has to be setup for a range of tapers, especially those with and without driving tangs. In otherwords the same mechanism that pushes out your dead center. Also pushes out the morse taper drill bit. You should be able to see this buy ejecting a dead center followed by a drill bit with a driving tang built in.
The very same thing happens on $80,000 toolroom lathes.
Ultimately there is no way to fire this as the lathe is designed. Simply put you need to accommodate anything with a morse taper that might get stuck in the quill.
There are other approaches, for example tools or centers with front extraction capability. That is a center that can have a nut screwed onto it to eject it from the morse taper. You could also build a custom quill that can eject a morse taper with a tang in the same way a drill press does. Of course the question is why would you do this when lathes have worked like this for centuries now.
Sent from my iPad using Model Engines
goldstar31
Well-Known Member
I'm in agreement with Wizard69 as one model engineer pioneered something called SkewRack Tailstock mechanism way back in- well, he wrote about it Model Engineer in July 1956. I'm sitting with a copy of the write ups but he came back and back to it on various lathes such as the Myford ML7 and then to the ML4 and even a lathe of his own design. He was the guy that patented the swing tool boring tool holders and went on to write Screwcutting in the Lathe.
From my limited researches, Martin Cleeve or correctly Kenneth C Hart, was quite a character. He hadn't enough money( or so he said) to continue his Patent application or buying a complete lathe so he bought half a lathe. He then added to it using bits of 'steel bar' and fastened them all together with socket screws which he made himself on his lathe.
It was all heady stuff as he was made 'redundant' and went on to using his lathe as a production machine making custom fasteners etc.
Suffice to say, I had no money either and made up quite a lot of his designs. Years ago, I tried to put his articles onto the net so that others could benefit. I simply ran into copyright problems so End of Story- sorry
Norman
From my limited researches, Martin Cleeve or correctly Kenneth C Hart, was quite a character. He hadn't enough money( or so he said) to continue his Patent application or buying a complete lathe so he bought half a lathe. He then added to it using bits of 'steel bar' and fastened them all together with socket screws which he made himself on his lathe.
It was all heady stuff as he was made 'redundant' and went on to using his lathe as a production machine making custom fasteners etc.
Suffice to say, I had no money either and made up quite a lot of his designs. Years ago, I tried to put his articles onto the net so that others could benefit. I simply ran into copyright problems so End of Story- sorry
Norman
