JW Early's Quick Change Toolpost Mod

Quick Change Toolpost Designs

• My own design
• John Stevenson's Q/C toolpost
• Ty Hoeffer's Q/C toolpost
• Dean Dempsey's Q/C toolpost
• George Carlson's Q/C toolpost
• Kevin Ferguson's Q/C toolpost
• Keith Mitchell's Making Wedge Type Toolholders

Update (02-20-14)
Several of the links in this document were to eGroups, the predecessor to Yahoo Groups back in there early 2000's.  They are no longer working, so I have struck through them.
End of update

JW Early is a professional machinist and a prolific contributor to the 7x10 interest group. He's come up with several outstanding improvements to the mini-lathe including this one to mount a rather large AXA size QCTP on the compound slide.

PDF file (large) with complete instructions for the mod. Note (02-20-14) This link is now working.

Here's JW's description of the QC toolpost mod:

http://www.egroups.com/message/7x10minilathe/8439

I have been thinking on the problem mentioned by several of mounting a QC
toolpost on the 7x10. All who have them have mentioned that they felt the
"A" size posts for 6 to 12 inch lathes are too large. I have one of the
ENCO/Phase II posts on my South Bend and recently got one of the HF 39083
sets for the 7x10. In carefully measuring the compound slide I found where I
can remove .250 from the bottom of the compound mounting base. I you will
remove the slide and hold just the base in your hand you will notice that
there is .400 from the bottom of the feed screw thread to the bottom of the
base. Now measure from the top of the base where the slide fits to the top
of the protractor and it should be .260. By taking off the protractor,
removing .250 from the compound base and then remounting the protractor you
will have gained .250 for the new toolpost. If you wish to go further the
step for mounting the 4-way holder is about .325 tall above the compound
slide, you may safely remove .200 from this area giving an increase of .450
total gain in room for the QC tool post. That is almost 1/2" more room. When
I mounted the 39083 post on my 7x10 with a 3/8 carbide insert holder in it,
I only had to drop the tool block .175 below the top of the boss on slide to
bring the cutter to center. With these changes I should be able to use 1/2"
cutters with ease. Also you can do the mod shown on Ty's page giving more
travel to the cross slide and have lots of room.
Now the second item in mounting the QC toolpost to the 7x10. Several have
mentioned the stud supplied is not the right size. Here is how to fix that.
The 7x10 stud is 10x1.25mm. The toolpost studs are 14mm or 9/16 in size. Get
a 10x1.25 tap at Home Depot or other handy store. Cut the supplied stud
about 3/4" longer than the tool post to allow room for the nut. Drill the
bottom of the stud 8.75mm or 11/32" and tap it with the 10x1.25mm tap the
same depth as the stud on the 7x10 compound is long. now lock the supplied
and modified stud down. Mount your new QC tool post and go to work with the
pleasure of knowing all of your tools are mounted and set for center and
ready for instant use.

http://www.egroups.com/message/7x10minilathe/11348

Yes all you do have to modify the compound base to fit the large tool posts. Here are 2 shots of #3 after the compound modification. I have not done the 1" cross slide mod as yet but it is coming next with some perks added of my own. If you want the complete instruction let me know and I will post it to you directly. PDF file 1.2 meg and shows marking out, facing off, drilling and all the grimy cast iron details. Any local in the LA area can come by evenings or weekends and look at it and see if they like the way it works. QC gearbox and power X-feed are next and I will have my dream machine, a shrunk SB that I can tuck under my arm and move it where I want to work with it. None of you can understand what it means to me to have a real tool post with preset tooling I can drop in and go with, without shimming and having tools I do not need bumping my hand while I am trying to do some work. Oops I almost forgot before I do much more I need to do the cam-lock thing on the SB it needs it almost as much as the 7x10 did.

PDF file (large) with complete instructions for the mod. Note (02-20-14) This link is now working.