Craftsman thread chart

[rockyrude]

I picked up a 101.07403 12" lathe. It didn't come with the change gear chart. I do have a 6" craftsman chart. Is the 6" setup the same as the 12" ?

 

[markba633csi]

I believe they are essentially the same, even though the gears themselves are different pitch (16 vs. 24)
Here is a 10F to compare:
-Mark

 

[Bi11Hudson]

The 12 inch machine does differ for different models. This I have run across trying to find parts for mine.(101.27440) If the 6 inch machine dates from near the 12 inch, they likely are the same, but don't take it to the bank.

Volusion Demo Store

This is a vendor for Craftsman parts, one of many. I can't find the one I was looking for, a site for most any make of machine. Perhaps someone will come along with the address. He is not a vendor, but a collector of information in England.

A primary source is the body of Atlas owners here. The Craftsman machine is made by Atlas and has mostly the same parts, the only difference being the increased head stock height. (Atlas 10"~Craftsman 12", from the same era)

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[mickri]

The gear change chart along with instructions on thread cutting for your lathe is located in the downloads. Look for Chapter 7 of the MOLO. You have to be a member to access it. Membership is inexpensive and well worth it to support the forum.

 

[wa5cab]

Technically, the term for the status necessary for access to Downloads is Donor. Actually, everyone who can post a response or a question here is a Member. But to gain access to Downloads and some other perqs, one must be a Donor (any level). The reasoning behind that rule is that the monthly bill to keep this site running includes the cost of the storage space (on the hard drive) and the software to run Downloads. So it was decided years ago to require a donation in order to access Downloads. Amounts run from $10 to $150, plus a couple of Commercial levels. Click the Donations tab on the top tool bar for the details, and optionally to make a donation.

Anyway, back to the question at hand, Trying to use the 6" threading chart for a 12" will probably sorta work but the 6" only does down to 8 TPI whereas the 9", 10" and 12" go down to 4 TPI. Plus for various reasons including the fact that the threading gear complement is different between the 6" and the larger machines. The Atlas MOLO (Manual Of Lathe Operations) is the User Manual for all of the Atlas lathes. It includes a chapter on thread cutting which includes the appropriate threading chart. If you are going to use your machine you really should acquire a hard copy. But the threading charts and so far a couple of copies of the MOLO are in Downloads.

Also, because of differences between the various machine sizes (6, 9, 10 and 12) (for example, the 9" and 10" except for those with a QCGB have a FWD/OFF/REV gearbox whereas the rest have a tumbler) and a few changes over the years, you are best off having the chart that matches your machine. And if you do decide to make a donation and use Downloads, first read the instructions on using it which will be found in the Sticky area of this forum only plus in the

HOW-TO USE THE FORUM TOOLS & FEATURES​

forum near the top of the list of all Fora.

And finally, unless the machine that you bought is missing the change gear cover or guard (some are), there should be a 12" threading chart that matches your machine (as it shipped, anyway) riveted inside of the guard..

 

[wa5cab]

The OP hasn't yet replied. But in any case, I'll add some comments about the MOLO's in general and Chapter 7 in particular. An edition of the MOLO was first published in 1937 and in most years thereafter up through 1981 plus 1988. As the equipment changed over the decades, so did the MOLO. So it is always best to get an edition published within a few years of when your machine was made. The early editions up through 1953 were only printed with the "Atlas" logo on the front cover. And to add further confusion, the first 15 editions only say "Copyright 1937" on the Copyright page.. Plus from about 1939 up through 1955, there was an Atlas 10" and a Craftsman 12" version of Chapter 7 printed each year. But the main and perhaps only differences were the photo, which showed the change gear end of either a 10" or a 12" lathe. And the drawings showing where each gear was placed either didn't or did show tumbler gears. At least one year, the threading section was for the Atlas 6". Whether a version for the Craftsman 6" I don't know. I'm still looking for it.

The 1954 and 55 editions added coverage of the QCGB.

1957 and later cover the 1/2" bed 12" and the 6" in Chapter 7. Although some photos still show the 10", mostly where the photo's purpose was to show an accessory that hadn't changed.

 

[rockyrude]

Thanks for all the help, next question, where would I find the gear setup for metric threads?

 

[pdentrem]

The metric chart is only in the MOLO unfortunately. You will also need a couple more gears to be able to do all threads but the common ones are doable with the factory gear set. I did a post listing all gears needed for the 10” lathes a few years ago.
Pierre

 

[mickri]

Does your lathe have a QCGB? The manual for the QCGB shows every possible thread that can be cut. For example one of my projects will require a 1.80 mm thread. That converts to 14.11 tpi. With the right gears I can cut a 14.1137 tpi. That is close enough for a 3/4" long thread. Like Pierre posted you can cut virtually any thread on a change gear lathe. There are programs online that will tell you what gears you need to cut different threads.

I purchased the gears I needed on Ebay. Boston Gear is another source for gears. Post what you need on the forum. Somebody will probably have the gear you need at a reasonable price.

 

[rockyrude]

I wish I had the QCGB, I only got three gears with the lathe. I need to learn how to calculate tpi from mm pitch