Gear experts pls

K

KSousa

Plastic

Joined

May 2, 2017

• May 2, 2017

• #1

New to the forum and learning as quickly as I can. Bought this 14-1/2" SB and almost up and running.
What I think I know is that the quick change gearbox talks about threading feeds which is something that I'll want to be able to do.
The gearbox has a few settings with a 48 tooth stud gear and then like 95% of the threads are with a 24 tooth stud gear.
I think I've identified where the stud gear is. In the second photo, the gear that I'm pointing to with the screwdriver has 38 teeth. The gear to the left of that one, on the same shaft, has 48 teeth.
So I think I need to obtain a 24 tooth gear and replace that 38 tooth?
Would that be the correct position for the 24 tooth gear?
Any help in identifying and sourcing the 24 tooth gear?

Thanks in advance for any assistance.

 

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K

KSousa

Plastic

Joined

May 2, 2017

• May 2, 2017

• #2

Looks like my second photo didn't upload so here's another attempt.

 

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K

kitno455

Titanium

Joined

Jul 9, 2010

Location

Virginia, USA

• May 2, 2017

• #3

You need to swap a 24 tooth gear in place of the 48 tooth gear. The 38 tooth gear from the inner layer of gears (the one with the screw driver pointing at it) does NOT come off.

Before you start digging around trying to buy something, open the hinged cover on the end of the lathe. $1 says you will find the 24 tooth gear being stored on the gearbox input shaft.

allan

 

K

KSousa

Plastic

Joined

May 2, 2017

• May 2, 2017

• #4

Great info. Thanks for the advice.
I did look inside and there is not a 24 tooth gear. There's a spot where a gear would ride, but I had to make up a spacer to take up that spot when I bolted the gear on the input shaft in place.
Any advice on sizing and locating the 24 tooth gear? I cannot easily access the rear to obtain ID, thickness, etc and I'd like to move it only once to put the new gear on. Thanks again.

 

T

tommy1010

Stainless

Joined

Apr 21, 2010

Location

northeastern Pa, USA

• May 2, 2017

• #5

What is the DP? PA should be 14.5. If 16DP and up they are readily available on amazon. If 12 and less they are available there too. 14 DP is the bastard size.

 

johnoder

Diamond

Joined

Jul 16, 2004

Location

Houston, TX USA

• May 2, 2017

• #6

Any advice on sizing

Click to expand...

Gears come in different tooth SIZES

The name for this is DIAMETRAL PITCH

To find out what DIAMETRAL PITCH you have you have to measure one of your gears - such as the one this side of the screw driver

You need a mic diameter OUTSIDE OF TEETH - hopefully the teeth are in good shape with no raised metal or burrs

You need an accurate TOOTH COUNT

Add TWO to that count

Divide the sum by the mic OD

EXAMPLE:

32 teeth, 2.125" OD

34 divided by 2.125 = 16 Diametral Pitch

You'll also need the other dimensions so you can modify (as needed) whatever gear is possible to buy of the tooth count and DP that you want

 

Last edited: May 3, 2017

D

Dobermann

Hot Rolled

Joined

Jan 2, 2014

Location

North Carolina

• May 3, 2017

• #7

As a side issue, the pictures of your gears show every indication that they've been lubed with grease. Before you go too far with your project, you need to clean that grease out of there along with the dirt and grit it's holding and lubricate the gears with oil instead. It will save you a lot of trouble down the road!

 

K

KSousa

Plastic

Joined

May 2, 2017

• May 3, 2017

• #8

Great info.
So I need to find a 24 tooth change gear with a 12 DP that is 1.00" wide and has an ID of .875

thanks to all for the help.

 

K

kitno455

Titanium

Joined

Jul 9, 2010

Location

Virginia, USA

• May 3, 2017

• #9

Boston Gear GD24 is close, but only .75 face width and the bore would need to be sleeved. I'd keep an eye on ebay for something closer.

allan

 

G

GenePoole

Cast Iron

Joined

Dec 8, 2012

Location

St. Louis, MO

• May 4, 2017

• #10

This is what the geartrain on a CL145 should look like. The SB 14.5 should be the same unless I'm mistaken:

The 48 tooth gear is "stored" by stacking it above the drive gear for the QCGB (which is a 64 tooth if I recall correctly). These are 14 DP gears with a 14.5 PA.

It looks like you have the 48T stud gear installed. You may need to buy a 24T if it is not "stored" stacked on the 64T QCTP drive gear.

If anyone knows for sure that the SB14.5 is different from the SB13, please let me know and I'll correct the post.

 

I

iwananew10K

Diamond

Joined

Sep 12, 2010

Location

moscow,ohio

• May 7, 2017

• #11

14.5 PA x 12DP gear....875" bore 3/4" face width...

NEW IN BOX Browning NSS1224 External Tooth Spur Gear 7/8" BORE, 24 TEETH, (A147) | eBay

 

K

KSousa

Plastic

Joined

May 2, 2017

• May 7, 2017

• #12

iwananew10K said:

14.5 PA x 12DP gear....875" bore 3/4" face width...

NEW IN BOX Browning NSS1224 External Tooth Spur Gear 7/8" BORE, 24 TEETH, (A147) | eBay

Click to expand...

That looks like it'll work. Thank you very much.

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