Gilmer to Polly V questions

tbirdtim · Post by **tbirdtim** » Sun Feb 02, 2014 7:35 pm

Hello from a "Newbie" and I have some questions. I just picked up a 1955 S/N 313619 and after disassembling the power unit I found the Gilmer sprockets are worn and need to be replaced. Can this be upgraded to the poly V or should I stay with the Gilmer style? Can I also upgrade at this time to the 2 bearing Quill? Does anyone on this forum sell these parts.

I have been repairing vehicles for over 35 years and know that the best answers comes from those with experience.

Thanks for your help and I am sure that I will have some more questions as I start to reassemble.

Tim

JPG · Post by **JPG** » Sun Feb 02, 2014 8:11 pm

A Gilmer to poly-v 'upgrade' includes all the following:

Upper shaft with pulley and bearings. The internal splines are different.

Idler sheave(pulley again).

Quill(splines again).

So a 'new' quill could just as well be a newer one with dual bearings.

Only you can say if it is worth the cost.

The parts are available from SS, but there be many used parts on ebay.

The newer parts are more common than the gilmer version.

Do be careful on e-bay, since some crazy prices are often 'over' paid for used stuff that can be bought new cheaper.

Adding a control sheave would be a prudent addition to the minimal list above.

I assume you agree new bearings are a no brainer.(at least for the upper shaft).

wa2crk · Post by **wa2crk** » Sun Feb 02, 2014 8:13 pm

tbird;
I do not have a lot of experience with the Gilmer drives but there is one here who does.Bill Mayo will most likely respond soon. When you say that the cogs are worn do mean the belt or the metal sprockets. I can't see the metal stuff wearing out but the rubber belt can sure go bad.
Bill V
PS WELCOME!!

beeg · Post by **beeg** » Sun Feb 02, 2014 8:16 pm

tbirdtim wrote:Hello from a "Newbie" and I have some questions. I just picked up a 1955 S/N 313619 and after disassembling the power unit I found the Gilmer sprockets are worn and need to be replaced. (1)Can this be upgraded to the poly V or should I stay with the Gilmer style? (2)Can I also upgrade at this time to the 2 bearing Quill? (3)Does anyone on this forum sell these parts.

I have been repairing vehicles for over 35 years and know that the best answers comes from those with experience.

Thanks for your help and I am sure that I will have some more questions as I start to reassemble.

Tim

(1)Yes you can upgrade it, BUT it's COSTLY.
(2)Maybe, contact Bill Mayo of this forum.
(3)Yes, contact Bill Mayo of this forum.

bill.mayo@verizon.net

billmayo · Post by **billmayo** » Sun Feb 02, 2014 11:11 pm

[quote="wa2crk"]tbird]

I find the metal teeth (sprockets) on the Gilmer Clutch pulley and/or the Idler Sheave pulley will wear down as much as 1/8". I normally machine the sprocket faces smooth if the wear is less than .030" but still trash about 20% of them.

I have available reconditioned Gilmer Clutches with new upgraded bearings on the Drive Sleeve shaft. I can rebuild yours if needed.

I have not been real happy using the Gilmer Drive system for the reversible motor headstocks and Shopsmiths that I use. A new Gilmer belt does not track as well (moves on the pulleys) as I would like when in the reverse rotation. Takes a lot of run time and some adjustment for the Gilmer belt to wear in and settle down. I have been using the Poly-V drive sleeve pulley and idler sheave with the Poly-V belt on the 6 spline drive sleeve shaft and using the 6 spline (Gilmer) quill assembly for my units. I do have double bearing Gilmer (6 spline) quills available. Also, I have available a complete Poly-V Drive system with a double bearing Poly-V quill, new upgraded bearings on the Drive Sleeve and a Control/Idler Sheave and shaft assembly to replace the complete Gilmer or Poly-V Drive system.

wa2crk · Post by **wa2crk** » Mon Feb 03, 2014 8:41 am

Hi Bill
I would not have thought that a rubber belt would cause that much wear to a metal part. I learn somethiing new every day. At least I can still learn!!:eek:
Bill V

billmayo · Post by **billmayo** » Mon Feb 03, 2014 11:41 am

wa2crk wrote:Hi Bill
I would not have thought that a rubber belt would cause that much wear to a metal part. I learn somethiing new every day. At least I can still learn!!:eek:
Bill V

The lastest Gilmer Drive system (1961) will be 53 years young so that is a lot of time that the headstock can be operated. I would estimate some Shopsmiths I see have over 20,000 hours on them and still operate, like the Timex watch. The balls of the bearings would actually fall out of the race when I remove them. You cannot believe the noise these headstocks were making and still operating when I got them. I guess the noise just slowly increases so the operator does not notice it. I find the gilmer belt can wear below the outside edges of the pulley and still operate. I am sure the Gillmer belt was replaced a few times. I find the motor belts can wear down to less than 1/4" wide and still operate with a limited speed range.

Even with all the problems I have seen, almost all the headstocks can be restored/rebuilt to like new or better condition. I found only two drive sleeve bearings that had frozen and spun in the casing so I had to discard these headstock casings to the salvage pile. This compared to more than 6 casing with a broken eccentric bushing ear that I had to discard. I found welding the ear back on the casing and restoring the area was much more expensive in money and time than just buying another used casing so only did it one time.

joshh · Post by **joshh** » Mon Feb 03, 2014 12:05 pm

billmayo wrote:I have not been real happy using the Gilmer Drive system for the reversible motor headstocks and Shopsmiths that I use. A new Gilmer belt does not track as well (moves on the pulleys) as I would like when in the reverse rotation. Takes a lot of run time and some adjustment for the Gilmer belt to wear in and settle down.

Skip said the same thing to me and Jerry (2centsworth) when we went to visit him last month. Both of the headstocks Jerry gave me to restore and reverse are Gilmers. What do you recommend? Running them awhile? Upgrading to a poly V?

billmayo · Post by **billmayo** » Mon Feb 03, 2014 10:09 pm

joshh wrote:Skip said the same thing to me and Jerry (2centsworth) when we went to visit him last month. Both of the headstocks Jerry gave me to restore and reverse are Gilmers. What do you recommend? Running them awhile? Upgrading to a poly V?

I sometimes get a little perfectist when rebuilding headstocks for my personal use. I have quite a collection of Poly-V parts so it was no problem for me to switch just the belt system. I have rebuilt over a dozen Gilmer Drives headstocks with reversible motors. I position the idler shaft in the eccentric bushing so when turning by hand in the normal direction, the Gilmer belt will ride about 1/16" off the clutch hub shoulder. The Gilmer belt will ride back againest the clutch hub shoulder when operating in the reverse direction. I have operated the headstock for many hours in the reverse direction without the Gilmer belt showing any adnormal edge wear. I just like to keep the Gilmer belt always off the clutch hub shoulder as many Gilmer headstocks I disassemble have this problem with the belt edge becoming frayed. I am unable to attach the below file.

Gilmer Belt Tension Adjustment

Sometimes the Gilmer belt will be positioned to far to the back of the headstock so the back of the Gilmer belt tries to ride up on the Gilmer clutch pulley housing. This will fray and damage the Gilmer belt. I investigated the reason and found that the 2 clips holding the eccentric bushing may set the eccentric bushing with the idler shaft too far back in the headstock. I seat the eccentric bushing against the longer leg of the clips and move/tap the idler shaft with the Gilmer belt forward while hand turning the quill shaft the same direction (important) as the motor does. This is with the eccentric bushing bolt and set screw still loose. I go for about 1/16” to 1/8" gap between the Gilmer belt and the drive sleeve pulley shoulder. I tighten the eccentric bushing set screw and adjust the Gilmer belt of 1/16"-1/8" deflection and tighten the eccentric bushing bolt (not too tight, I normally just flatten the lock washer). This may set the Idler Shaft Bearing any where for 0” to ¼” deep into the eccentric bushing. I make sure the Gilmer belt stays tracking really close to the Idler Sheave pulley shoulder. I use a 5/16“ X ¼” Knurl-Grip Cup Point Set Screw to securely hold the Idler Shaft bearing within the eccentric bushing. Do not use the cone point set screw that came in the eccentric bushing. This cone point set screw can deform the Idler Shaft Bearing resulting in noise and failure.

I operate the headstock for some time to may sure the Gilmer belt is not touching or creeping toward the drive sleeve pulley shoulder.

tbirdtim · Post by **tbirdtim** » Tue Feb 04, 2014 10:14 am

Bill, do you have some prices? I did send you an email.

Tim