ARC-170's Craftsman 101.07403 lathe restoration thread

[ARC-170]

8. I was looking at various retail QCTP holder sets. What is the stud with the nut and washer for on all the QCTP tool holders? I've used this type of holder before but none of them had this. The height adjustment on the ones I've used is done with a socket screw; this stud appears to just screw into the same place as the socket screws that hold the tool bit. Can someone clear up my confusion?

 

[mickri]

Are you asking about the norman style like I am making or the aloris style? A picture would help.

 

[markba633csi]

ARC: the gib screws on your compound need to have nuts to lock the adjustment-
Mark

 

[wa5cab]

Yes, I missed that. None of the compound gib screws are original. They should look like the four on the cross slide, except a size smaller.

It is unlikely that they will need replacing as the steel ones usually last forever. But if you do, I have the steel gibs available, new manufacture. The factory switched to plastic ones in the 1970's, one of the few mistakes that they made.

The stud, knurled thumb nut, light spring washer, and hex nut on the top of most QC tool holders are for setting the cutter height.

One problem with making you own QC, or one of them, is that of the #101 or #102, you will need several. Which adds to the time expended. The reason that you will need several is that with only one, you lose a large advantage or the QC over the lantern type holder. A typical job might call for one turning cutter, one facing cutter and one beveling or chamferring cutter. Every time that you needed to change cutters, you would have to go through the setup procedure to get the new cutter on center. So you aren't much better off than without a QC. Counting some 101XL's, I have around 15 of them. Pretty much anything that I need to do, I just grab the holder with the appropriate cutter.

 

[mickri]

I have realized the same thing with my norman style qctp. I am almost done with the first 7 tool holders and can see where I will need at least 4 or 5 more. It has taken me a long time to make them. On the other hand the cost has been minimal. Being retired I have nothing but time and I am learning a lot along the way. I have two boring bar holders, one holder for parting and one holder for threading. The other three holders I plan to have one for facing, one for turning and one that will be used for whatever I happen to need until I get more made.

 

[ARC-170]

Are you asking about the norman style like I am making or the aloris style? A picture would help.

What are the posts on the tool holders that have gold and silver nuts for?

 

[ARC-170]

What if I got a QCTP that held four tool holders? I could set all four up and just rotate the post, correct?

 

[wa5cab]

What you are describing is called a Turret tool post or 4-Way Turret, not a QCTP. They are generally better than the lantern type (and by the way, the lantern type has one advantage over the QCTP, which is that on rare occasions they may allow you to get the cutter into the work without the TP being hit by or hitting something but generally not as convenient as the QC. The other problem with the 4-Way is that you can't always mount four cutters in it because when one cutter is selected, another one may be hitting the work, chuck, etc. And if one of the cutters installed is for facing, it can't be installed in the position CW of the turning cutter because it would be crossing the turning cutter. Just bite the bullet and get the QC.

Also, the 4-way does not use separate cutter holders. The cutter is mounted into the 4-way just as it would be mounted into the QC holder. And finally, there is no way to adjust the cutter height (to get it on center) other than by shimming up under the cutter in the 4-Way.

I answered your final question yesterday but somehow it is above the question. The gold nut is the height adjustment and the silver one locks it in position.

 

[ARC-170]

9. I'm looking for a change gear set. I need 24, 32 (x2), 36, 40, 44, 46, 48, 52, 54 teeth gears. This is from the parts manual for this particular machine, so I'm assuming it's accurate, I've found a few sets on ebay, but they are missing one gear and might have an extra one. Should I buy a set that is not exact, or wait until a complete one comes up?

 

[mickri]

You might never need the missing gear. You can always buy the gear that is missing if you should happen to need it. I would go over the threading chart for the gears needed to cut common threads and any threads that you anticipate cutting to see if the gear set for sale has the gears you need. Be sure to check for the gears needed to cut the common metric threads. It is my understanding that atlas/craftsman has a chart listing every possible thread that can be cut on a change gear lathe.