Came across this yesterday:
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Its not the right arbor for my mill, but I though it might be possible to disassemble it and modify so I can use it.
Anyone know anything about them? Particularly how to disassemble and also how they are used. Neither is obvious to me at first glance.
I can't seem find anything online about them.
Steve
I picked up a tapping head earlier this year with a 3MT shank which also doesn't match any of my gear. Although yours is a different style, I expect the principle is the same- the body needs to be prevented from rotating by bracing against the column of the machine, the gearing inside is cunningly contrived so that when you apply downward pressure with the quill, the tap rotates clockwise; when you stop applying downward pressure, the tap stops turning, and when you apply upward pressure, the tap reverses- all with the machine spindle rotating clockwise. I may of course be barking up the wrong tree as yours looks quite different to mine, perhaps there is some other means of auto-reversing.
Mine works the same way. But as I recall, even with the downward pressure, when the tap stops it automagically reverses.
When I got it, I got it on ebay from total morons. It said that it comes with an MT-2 arbor, it came with two off the wall arbors. I emailed them about it and they said MT-2 means it "MighT come with 2 arbors". Since it was about $30 less than what everyone else was getting for the same one I didn't bother sending it back. It was easier to spend the $8 and get the right one from someone else.
Thanks guys.
I can feel that it drives clockwise when pushed in by hand, and sort of feels like it disengages when you take the pressure off. Doesn't seem to ever get to a reverse situation though - but hard to know whether it needs some dynamic assistance to make that happen.
One part that has me confused though is that the small lock on the side locks the alloy arm to the arbor by default. Maybe there is meant to be another arm that attaches and releases that lock and keeps the housing stationery, otherwise as it is now the whole alloy housing would be locked to the arbor and spinning all the time.
I'll have a closer look and try and work out how it comes apart with a view to changing the arbor. Seems there's a bearing retainer above the chuck but I'm hoping not to have to disassemble it completely...
I'll also still need to find out how the chuck works.
BTW Pete - I'm pretty sure the guy has more of them around with the same arbor if you're still looking for something that fits yours. I'm not sure exactly what the taper is but can measure if required. This one cost me $20 and I'll probably be calling in on him again soon.
Steve
Looks like it holds Bilz type tap holders. They come in 3 or 4 outer diameters, with numerous inner diameters to take standard tap shanks. There are torque limiting ones and solid ones.
It's unlikely to be an auto reverse of the sort that you use on a manual mill, as the CNC machine does the down feed / reverse / infeed with the holder allowing a little axial float to compensate for slight errors in the programmed pitch compared to the tap pitch.
(08-21-2017, 01:09 AM)SteveG Wrote: [ -> ]BTW Pete - I'm pretty sure the guy has more of them around with the same arbor if you're still looking for something that fits yours. I'm not sure exactly what the taper is but can measure if required. This one cost me $20 and I'll probably be calling in on him again soon.
Steve
Don't worry Steve...Yours looks like a #40 taper, the one I have has a MT3 adapter that some clown has welded over the top of a MT2 arbor that would actually fit my drill press if I can cut the adaptor off without destroying it. However, it looks like I might be shopping for stuff in R8 soon.......
(08-21-2017, 01:25 AM)awemawson Wrote: [ -> ]Looks like it holds Bilz type tap holders. They come in 3 or 4 outer diameters, with numerous inner diameters to take standard tap shanks. There are torque limiting ones and solid ones.
It's unlikely to be an auto reverse of the sort that you use on a manual mill, as the CNC machine does the down feed / reverse / infeed with the holder allowing a little axial float to compensate for slight errors in the programmed pitch compared to the tap pitch.
Thanks - I'll check out the Bilz holders.
Steve
(08-21-2017, 01:09 AM)SteveG Wrote: [ -> ]...I'm pretty sure the guy has more of them around with the same arbor if you're still looking for something that fits yours. I'm not sure exactly what the taper is but can measure if required. This one cost me $20 and I'll probably be calling in on him again soon...
Steve - I'm certainly interested
(08-21-2017, 05:31 AM)Mayhem Wrote: [ -> ] (08-21-2017, 01:09 AM)SteveG Wrote: [ -> ]...I'm pretty sure the guy has more of them around with the same arbor if you're still looking for something that fits yours. I'm not sure exactly what the taper is but can measure if required. This one cost me $20 and I'll probably be calling in on him again soon...
Steve - I'm certainly interested
No drama's. Have sent you a PM.
Steve
The tap has to still be in the piece you're tapping when the quill wants to go up in order to get it to reverse. As soon as the tap clears the work piece it no longer turns in reverse.