Wanted Sheldon 11" Lathe metric change gears parts

[gunner312]

I recently was given (yes, GIVEN wa hoo!!!!) a sheldon 11" lathe, it has a lot of attachments and etceteras with it but is missing most of the metric change gear set-up.

I need to either 1. obtain a set of the change gears, the main compound metric gear is a 127/110 gear, the others are 26,28,32,36,40,48 tooth.

Option 2 is to make the gears myself, but, I need the OD's and the width of the gear blanks, so does anyone have the gears on hand and can supply me the dimensions?

I would appreciate it.

Semper Fidelis

Jim Wright

 

[krypto]

Buying used gears will always be quicker and less work, but you need the gear bore diameter, PA and DP to make sure you are getting the correct gears for your lathe. Don't trust the seller. I don't what that is for a Sheldon lathe.

You can make gears as well, but it's time consuming. When you have the DP and tooth count you will know the gear diameter. You will probably have trouble dividing a 127 tooth gear.

The gear on the left is a 127/100 metric transposing gear for my SB10K lathe. The gear on the right is a 80/63 transposing metric gear. It's smaller but is slightly inaccurate (1.2698 vs perfect 1.27 ratio) although I wasn't able to notice a difference in single-point threading a bolt during testing. It's also 3D printed.

One of these gears was much more work to make then the other. Can you guess?

I have a full set of metal metric transposing gears (bought) for my lathe and I made the 42 tooth gear above for practice and possible use in the future. Having said that, for occasional use the plastic change gears are totally adequate.

 

[kf2qd]

What do you need different for metric other than the 127 tooth gear? All i have to do is change out one gear and use the existing gear and use the same change gears for metric or inch. Aren't going to make many changes to a quick change gearbox to change over, and the same gears do both.

 

[krypto]

That's great but that's not how all lathes work. You need to swap gears and select a setting on the QCGB on mine for metric which is pretty common on older lathes.

 

[KellisRJ]

Hi krypto. I have a 10" Logan and ~99% of the 10 & 11" parts are interchangeable. I have a spreadsheet I've made listing the most common metric threads and the required gears. It's been a work in progress, but the information is there, just not in a professional layout. I also have the table Scott Logan provides on the QCB settings. Scott is the grandson of the founder.

Only a few gears other than the ones supplied with QCGB are needed for the most common threads. The Hobby Machinist forum has a large Logan sub- forum and IIRC all the gear information for making them is there. There are two other sites moderated by Scott, one on Facebook, the other migrated from Yahoo to Groups.io. I hate Facebook's structure, spend little time there. I like the groups. io much better and there are decades of postings. Out of respect for Scott, on both FB and groups.io the only mention of manuals is to Scott's site. But if you throw a donation to Hobby Machinist for access to their files, I believe an 11" is posted there. I'm also 99% sure Vintage Machinery has a copy, with a short history of Logan. I use a nylon transposing gear, has held up fine, and have one other size custom made very inexpensively by an eBay vendor who knows what they are doing from making printer cartridge gears. I see they often have Logan gears listed. I'll post the file if you are interested. It's open source format so OpenOffice, Google Docs, or Excel will open it.

Ron

 

[Richard Hed]

I recently was given (yes, GIVEN wa hoo!!!!) a sheldon 11" lathe, it has a lot of attachments and etceteras with it but is missing most of the metric change gear set-up.

I need to either 1. obtain a set of the change gears, the main compound metric gear is a 127/110 gear, the others are 26,28,32,36,40,48 tooth.

Option 2 is to make the gears myself, but, I need the OD's and the width of the gear blanks, so does anyone have the gears on hand and can supply me the dimensions?

I would appreciate it.

Semper Fidelis

Jim Wright

Gunnar, good to hear from hyou. I have some random gears, If you can get the diameters of the centers, I can check for some of that center size. I have a set of some that are for much larger machines too, with centers of almost 2 inches. Don't know what lathe they are from.

 

[MRA]

In case it is useful - I use an 80-63 pair on my Boxford (like a SB9") which I made. There's a thread here (which takes a while to get going!) on making the 63t gear

https://www.homemodelenginemachinis...dscrew-80-63-approximation.32655/#post-354402
and the web site I copied when I made the hob is here

http://www.helicron.net/workshop/gearcutting/involute-gears/
Casting the blank was just fancy, really - any old lump of material would serve. In general it is useful to know that 'diametral pitch' (how many teeth-per-inch your gear has) is given by

DP = (N+2) / OD where N is number of teeth, OD is outside dia in "

- so once you know what DP your gear set is (they will all be the same, or they will not mesh) then you can work out the OD of the blank you need to make one of however many teeth.

 

[KellisRJ]

I recently was given (yes, GIVEN wa hoo!!!!) a sheldon 11" lathe, it has a lot of attachments and etceteras with it but is missing most of the metric change gear set-up.

I need to either 1. obtain a set of the change gears, the main compound metric gear is a 127/110 gear, the others are 26,28,32,36,40,48 tooth.

Option 2 is to make the gears myself, but, I need the OD's and the width of the gear blanks, so does anyone have the gears on hand and can supply me the dimensions?

I would appreciate it.

Semper Fidelis

Jim Wright

Dp =16
Pa = 14.5
Width = 7/16"
Bore = 5/8"
Keyway = 5/32" wide, 1/16" deep
The 47/37 transposing gear will fit under the cover with 0.02% accuracy.

 

[KellisRJ]

Logan QCGB required gears, only 2 come from a plain geared lathe for the most common threads.

	Standard
42	Yes	LP-1059
48
54	Yes	LP-1070
66		LP-1060
72	Yes	LP-1075

Shaft	Pitch	Head	Gear
M2:	0.4mm	4mm
M2.5:	0.45mm	5mm
M3:	0.5mm	5.5mm
M4:	0.7mm	7mm	42
M5:	0.8mm	8mm
M6:	1mm	10mm	48
M8:	1.25mm	13mm	60
M10:	1.5mm	17mm	72
M12:	1.75mm	19mm	42
M16:	2mm	24mm	48
M20:	2.5mm	30mm	54

My color coding didn't paste so I quickly added two columns and "Yes"

Pitch	Gear	Selector A	Selector B	Common Thread	QCGB Standard Gears
6.00	72	A	1
5.50	66	A	1
5.00	60	A	1
4.50	54	A	1
4.00	48	A	1
3.50	42	A	1
3	72	B	1
2.75	66	B	1
2.50	60	B	1
2.25	54	B	1	Yes
2.00	48	B	1	Yes	Yes
1.75	42	B	1
1.50	72	C	1	Yes
1.40	42	B	3
1.3	39	B	3
1.25	60	C	1	Yes	Yes
1.20	72	C	3
1.1	66	C	3
1.00	48	C	1	Yes	Yes
1	48	C	1	Yes	Yes
1.25	60	C	1	Yes	Yes
1.50	72	C	1	Yes
1.75	42	B	1	Yes
2.00	48	B	1		Yes
2.25	54	B	1

 

[KellisRJ]

OK, officially brain dead. No idea how I misread this. Crawling back in my hole . . .

 

[SmithDoor]

I recently was given (yes, GIVEN wa hoo!!!!) a sheldon 11" lathe, it has a lot of attachments and etceteras with it but is missing most of the metric change gear set-up.

I need to either 1. obtain a set of the change gears, the main compound metric gear is a 127/110 gear, the others are 26,28,32,36,40,48 tooth.

Option 2 is to make the gears myself, but, I need the OD's and the width of the gear blanks, so does anyone have the gears on hand and can supply me the dimensions?

I would appreciate it.

Semper Fidelis

Jim Wright

Most overlook or like 127 gear but you can make with simple dividing head 37/47 gear set

Dave