# adaptor



## taycat (Sep 30, 2017)

right might be getting new place soon where i can set up some of my tools.
my lathe will be my chinese one as got most bits for it chuckwise etc.
i also have a southbend model c 9" resto project.
as two chucks and couple of faceplates ( i have  none for chinese one ) and full set 3c collets.
my plan is to make adaptor from piece of rd stock that is copy of sb spindle end to use sb parts incs collets.
anything to watch out for?
or anyone got drawings of spindle end to speed it up?


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## 4GSR (Sep 30, 2017)

If you have a copy of the South Bend lathe book "How to Run a Lathe".  Look at the last page or two in the book.  It gives the dimensions of the spindle nose for the 9" lathe.  
I have an original collet adapter form my 9" SBL I could reverse engineer and draw up.  I won't have time for a couple of weeks to touch it.  But if you can wait, I'll be glad to draw it up and post here if you like.
Ken


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## taycat (Sep 30, 2017)

i don't have copy of it but will find it ta.
no rush on drawing but be much appreciated thanks


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## 4GSR (Sep 30, 2017)

taycat said:


> i don't have copy of it but will find it ta.
> no rush on drawing but be much appreciated thanks


I believe there is a copy of it in the download section of the forum, if you can find it!


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## francist (Sep 30, 2017)




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## taycat (Sep 30, 2017)

you're a star francist thank you


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## taycat (Oct 1, 2017)

right just seen article on uk forum where guy made an er 40 chuck from a solid piece of 5" rd steel.
nothing fitted after few days.
one of comments said steel had destressed itself and warped.
am i better of roughing it out ie thread is 1.5" so turn it to 2.5" etc and  leave it for week or so to settle if is going to, then also turn register for spindle?
and do i drill centre hole when roughing out will do undersize?


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## Asm109 (Oct 1, 2017)

Yes you should rough everything out. OD and ID. Then go back and bring the OD and ID features to final size.  I believe the warpage and distortion will occur as the material is removed.
IE you don't have to wait days. Just rough everything and then finish.

This spring I made the adapter for collets to the spindle on my SB Heavy 10.
I used the compound to cut the tapers.

Here is the sequence of operations I used.

1. Install indicator on compound with tip and spindle center height Exactly.
Indicate along the spindle taper on the back side of taper (away from operator). Adjust compound until indicator has 0 motion.

2. Install 3 jaw chuck and Put material for adapter into chuck. I used 4140 Pre heat treated.
3 Turn OD to diameter of flange +0.020 inch. Turn down part that will become taper. Turn cylindrical to 0.020 over the large diameter of taper.
4. Drill ID and bore to diameter .020 smaller than the back of the collet. 
5. Bore a relief in the inside of collet about .060 larger. start the relief about 1/2 inch  in from end of part.
6. Rough the taper using the compound.
7. Finish turn the taper to size.
8. Go back and finish bore the end of the bore to the size for the collets. It needs to be a close sliding fit .0005-001 clearance.
9. Remove part, Install 4 jaw chuck and install a collet, indicate collet in to 0 rounout.  Stick a dowel pin or other precise piece of stock in collet and close collet with a hose clamp.
10. Mount the indicator on center height and adjust the compound to cut the taper of the collet.
11. Remove chuck and put your part directly into the spindle. Tap it in with a soft mallet.
12 Taking small cuts, turn the OD of flange to size, Face flange to size.
13. Use compound to cut taper for collet.
14. Done!

This approach cuts the OD taper and the rear collet mounting feature in 1 setup. Therefore no runout.
The front tapered surface is cut with the OD taper mounted directly in the spindle.  Again 0 runout.


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## Mark_f (Oct 1, 2017)

I have a print to make the 3C collet adapter for the SB 9 lathe. It is on this forum somewhere but I can't find it. I can repost it if you need it.


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## Mark_f (Oct 1, 2017)




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