Yet another adapter and chuck mating thread

adamsgt

adamsgt

Jerry Adams
Whenever I try to do something I've not done before I try to get as much info and advice as I can before starting. This is a Bison 5C chuck and Bison adapter.

So, I need to get these two guys together and this is not set-tru.

DSCN0735.jpg


In another thread, Jackie referred to M/F spigots. I've not heard that before but as he is certainly a master in this arena I'll try to use the same terminology. In this case the male spigot is 3.886" in diameter and the female spigot is 3.735" in diameter, a difference of .151. The male spigot is .110 long and the female spigot is .173 deep. The outer register area of the adapter is .553 wide. So, that's what I know so far.

Obviously I have to reduce the diameter of the male spigot to fit into the female spigot. The little instruction sheet that came with the chuck says to establish a press fit. So, .001 - .002 oversize with a bevel cut on the edge of the male spigot? I assume the press fit is established with the connecting bolts.

Now for the outer area of the adapter, do I indicate it first to see how good it is or just cut it anyway and if so, how much? There's .063 between the top of the male spigot and the bottom of the female spigot so I don't think I want to take off enough of the outer edge to allow these surfaces to come into contact.

Which is best to attack first, the male spigot diameter or face off the outer register area? I'm a little concerned about getting a proper shoulder at the junction of the register area where it meets the male spigot.
 
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G'day Adamsgt

Mate i think the first thing you need to decide is if this is going to be a heavy duty working chuck doing big interupted cuts or just for fine finishing work.
If it's the later i would be inclined to actualy have some clearence between the spigot and recess to allow you to take the pressure off the bolts and using a soft hammer to make work peices in the chuck run true. Basicly like a poor mans set true chuck.

I would set the cam lock adaptor on the spindle and try all three positions for the best runout, then mark the adaptor and spindle so it can be placed back in this same position.

If you are going to have some clearence then about 5-10 thow would be ok. I would then take a minimal trueing cut on the face the adaptor down the the spogot. Then rough the spigot down to the finial cut. When taking the final cut go about 2-4 thow into the face and then recut the face from the center out. As long as the tool has a radius smaller than the chamfer on the chuck you wont have any problems.

If you are goimg for a press fit then i would say that interference of 1-2 thow would be right.

You can then machine a small taper on the front of the spogot.

Cheers
Leeroy
 
The pilot should be an exact-as-possible fit to the recess in the chuck. .350" is too much. If they are both from the same vendor, I would say you have the wrong backplate for that chuck, or it is a mistake. The procedure is this: You have a pilot which is too large, you mark your backplate and lathe spindle so you can register the backplate to the same position when you remount it, then you turn the pilot to the chuck recess on your lathe. A .350" undersize pilot is no pilot.
 
Oops

couldn't read my own writing. The male spigot(pilot) is 3.886 in diameter. See why I'm asking for help? Can't get nothin right.
 
Well, now you got it made. Put the backplate on and turn it until you get close and use the chuck as a guage to get a zero fit. then bolt her up. Again, there is no harm in marking the position relative to the spindle so you can always put it back in the same place.
 
Nothing goes easy

Well, got the adapter on the spindle and found the position with the least runout and went to set up for the cut. Found out that I can't reach the face of the adapter with the lathe bit. The saddle is all the way to the left and the compound is as far forward as it will go. I could run the tool holder out a bunch but it would really be hanging out there if it does reach. Looks like I'll have to remove the threading dial but I'm not sure that will give me enough either. My back was hurting so I gave it up for today.


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Any thoughts?
 
If it was me, I'd try removing the thread dial and and QC tool post. The I'd make a tool holder out of a "chunk" of metal that bolted to the compound using your existing T-nut but which is big and heavy, and use that to hold the bit where it is needed.

That might solve the current problem, but I see another, possibly more serious issue - how are you going to hold the threading tool in position to thread the barrel tenon with the thread dial in place, which it will have to be for threading unless you don't disengage the half nuts at all?

Fitch
 
Move the thread dial to the other side of the carriage,and/or use a boring bar.
 
Move the toolholder outward, (2) screws will clamp the holder just fine if taking light cuts................done in less than a minute..........Don
 
You are probably going to have to move that threading dial to get close enough to the chuck to thread a barrel. Never would have thought about that without seeing that picture.

Joe
 
Finally

got it on. Followed Don's advice and moved the tool holder out just enough to catch the adapter. Took light cuts and it worked.


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Still have the issue of the threading dial. When I ordered a mounting bracket for my trava-dial from SWI, the gal recommended a "Universal Bracket" because you can mount a threading dial on the outside right leg.

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Once I determine what modifications I need to make to the bracket and get the Trava-dial mounted, I'll move the threading dial. That should finish that up if I do any of it right. :eek:
 
Jerry,

Dont forget to return the toolholder to the original 3 or 4 screw clamp position, although you can use it in a 2 screw clamp length with small cuts, it is much more rigid and produces superior/larger cuts when more supported.

Also, it looks like you have the toolholder set way too low (unless it is just an optical illusion of the photo angle), it should be set on or near center for most cutting applicaitons. I usually set mine using live or dead centers.......................Don


adamsgt said:
got it on. Followed Don's advice and moved the tool holder out just enough to catch the adapter. Took light cuts and it worked.


DSCN0738.jpg


Still have the issue of the threading dial. When I ordered a mounting bracket for my trava-dial from SWI, the gal recommended a "Universal Bracket" because you can mount a threading dial on the outside right leg.

DSCN0741.jpg


Once I determine what modifications I need to make to the bracket and get the Trava-dial mounted, I'll move the threading dial. That should finish that up if I do any of it right. :eek:
Click to expand...
 
Don, that's an illusion. I used a 5 mt dead center in the spindle to set the tool holder for this operation. I have two more backplates to do, one for the 3 jaw set-tru and another for a bed side spider. After those are done I'll mount the Trava-dial and then the threading dial. Then I'll start to practice my threading, after changing three gears in the lathe.
 
adamsgt said:
Don, that's an illusion. I used a 5 mt dead center in the spindle to set the tool holder for this operation. I have two more backplates to do, one for the 3 jaw set-tru and another for a bed side spider. After those are done I'll mount the Trava-dial and then the threading dial. Then I'll start to practice my threading, after changing three gears in the lathe.
Click to expand...

Sounds like you have a full plate for the near future!.............Don
 
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