Author Topic: Southbend Metric Transposition set.  (Read 13148 times)

Offline steamer

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Southbend Metric Transposition set.
« on: December 27, 2014, 08:32:43 PM »
Just picked up one of these sets as well....I can do metric on the Samantha Bell now as well.

http://www.ebay.com/itm/NEW-METRIC-TRANSPOSING-GEARS-FOR-SOUTH-BEND-9-10K-LATHE-For-Repair-/141519320582?pt=LH_DefaultDomain_0&hash=item20f3357606

Sounds like an easy fix.


Dave
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Offline Don1966

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Re: Southbend Metric Transposition set.
« Reply #1 on: December 27, 2014, 08:45:58 PM »
Nice find Dave!  :ThumbsUp:

Don

Offline b.lindsey

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Re: Southbend Metric Transposition set.
« Reply #2 on: December 27, 2014, 08:50:14 PM »
You going metric on us Dave??   :lolb:

Bill

Offline steamer

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Re: Southbend Metric Transposition set.
« Reply #3 on: December 27, 2014, 08:54:28 PM »
Gotta complete the capabilities!  :LittleDevil:   Some of the truck is metric...and I have a few changes I want to make.

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline b.lindsey

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Re: Southbend Metric Transposition set.
« Reply #4 on: December 27, 2014, 09:41:25 PM »
Definitely a worthwhile endeavor then :)

Bill

Offline Mosey

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Re: Southbend Metric Transposition set.
« Reply #5 on: December 27, 2014, 09:51:55 PM »
I have been eyeing that set for decades, is this the one to buy? What does he mean about the gears not being pinned together?
Mosey

Offline steamer

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Re: Southbend Metric Transposition set.
« Reply #6 on: December 27, 2014, 10:07:43 PM »
this set has an issue with the Transposition gears not being pinned together correctly, so are $50 off full price.    I figure I can sort that out and save the $50.

There are more of the "defective" sets available at that price...or.

You can buy the "good" set for $200.

This set is a duplicate of the SB set.   

The 100/127 gears could be replaced with a 37/47 set and be able to keep the gear guard on......but you need all the other gears as well.    I could make all of them, but it's cheaper in time and tooling to just buy it.

Dave



www.tools4cheap.net


Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline Mosey

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Re: Southbend Metric Transposition set.
« Reply #7 on: December 27, 2014, 10:20:42 PM »
Cool!
If your mount the metric transposition gears, your overall ratios are then 13% off of the gearbox plate. So, can you leave the metrics on and your speeds and feeds will be slightly off?  (Lazy, huh?)
This would be a good time to make all of those W-12 and W-20 bits I have been meaning to make. Collet blocks, arbors, etc.
Mosey
« Last Edit: December 27, 2014, 10:27:58 PM by Mosey »

Offline steamer

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Re: Southbend Metric Transposition set.
« Reply #8 on: December 28, 2014, 01:09:01 AM »
If you have the "A" the feeds will be altered ...they are more intended for occasional use....for cutting threads.

Yes...now would be that time to cut some W12 or W20 threads....   W20 is a 5 x 45 Buttress thread with a 1.6667mm pitch ...... 8)

Don't even know if it will do that directly.   If you put the Transposition set in and it is set for reduction, then set the quick change to 12, and you will get 0.0656" pitch which is near enough 1.6667mm pitch

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline steamer

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Re: Southbend Metric Transposition set.
« Reply #9 on: December 28, 2014, 01:19:29 AM »
Here's what South Bend has to say on the subject

http://img.photobucket.com/albums/v727/vmil3/SB8tpileadscrewmetricchart.jpg


So we need to make some adjustments to do a 1.667 mm Pitch

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline steamer

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Re: Southbend Metric Transposition set.
« Reply #10 on: December 28, 2014, 01:59:49 AM »
Set the lathe up to cut 12 threads per inch... 20 tooth on the stud, 56 on the screw.   Set the 56 tooth gear to the outside with the spacer to the inside.

Insert a 100/127 or 37/47 transposition pair in place of the idler.   The 127 tooth gear engaged with the 20 tooth stud gear while the 100 tooth gear engaged with the 56 tooth gear.   47 to 20 and 37 to 56 respectively.

Set the QCGB to 12 and you will get 1.6667mm pitch  ( 127/100 = 1.27 x 12 = 15.24 threads per inch which is 0.0656" pitch or 1.6679 mm pitch)

QED

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline Mosey

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Re: Southbend Metric Transposition set.
« Reply #11 on: December 28, 2014, 02:06:30 AM »
Gearset ordered!
I'll bug you later for the pin fix.
Mosey

Offline steamer

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Re: Southbend Metric Transposition set.
« Reply #12 on: December 28, 2014, 02:09:40 AM »
Then I better figure out how to do it!    :lolb:   Said he'll ship Monday...so some time next week.


Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline Mosey

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Re: Southbend Metric Transposition set.
« Reply #13 on: December 28, 2014, 03:01:09 AM »
You are the man!
Mosey

Offline jschoenly

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Re: Southbend Metric Transposition set.
« Reply #14 on: December 29, 2014, 05:57:02 PM »
I haven been changing around the shop and as such have gone away from South Bend for now (I'll miss them).  Anyway, I have a set of these that was only used once if anyone is looking to buy as set.  Feel free to PM me.  Worked great, just sold the SB and don't need them now.
Jared
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