A little Machinist advice please

[torch]

I changed my mind. Maybe it is a Woodruff key.

Yeah, the dimension IS awfully close to a 1/8" key. I hadn't noticed that and it's certainly not standard to find that in a metric hub, but it wouldn't be the first time a manufacturer mixed and matched as they saw fit.

So assuming they used a 1/8" key in a 10mm shaft, the question becomes how deep did they set that key? Keyslots are cut to 1/2 the key depth at the chord. If they did that then the measurement across the shaft to the key face should be 11.33mm.
Alternatively, if they just cut the slot to the depth of a conventional 3mm key, it would protrude further and the measurement would be 11.63mm.

You measured 11.51mm. Hmmm.

 

[Old Machinist]

It took 21 posts to get the model number in question. You can learn a lot by looking up exactly what you are working on. Apparently there are two serial number breaks for the JX75 but both seem to have the same transmission.

https://partscatalog.deere.com/jdrc/navigation/equipment/22632

The M113895 drive pulley I see on the parts list doesn't resemble the pulley shown by the OP. I found a good used one of those on eBay for $10. I may be looking at the wrong area for the mower in question?

JD lists sizes for shaft keys in the descriptions. They also will list if a nut is metric. The M85516 lock nut for the idler pulley says it's a M10 but that pulley has a 1/8" X 1/2" shaft key. Go figure?

I suggest backing up and figuring the exact model number mower and look up it's parts at JD to make sure what you need. Sometimes searching for the part number needed can save a bunch of time and money.

 

[torch]

Is that maybe a woodruff key? https://www.fastenermart.com/files/woodruff-key-dimensions.pdf

Yeah, in retrospect I think you are right. The numbers would make sense too -- with a 1/8" x 1/2" Woodruff key and standard slot depth for such key, the overall measurement across both shaft and key works out to 11.48mm -- pretty darn close to the 11.5mm shown.

 

[torch]

JD lists sizes for shaft keys in the descriptions. They also will list if a nut is metric. The M85516 lock nut for the idler pulley says it's a M10 but that pulley has a 1/8" X 1/2" shaft key. Go figure?

Good catch. Many manufacturers don't give specific sizes in parts diagrams, just their own part number. Nice to see JD is giving the size. More than that, it confirms it is a Woodruff rather than a machine key.

I suggest backing up and figuring the exact model number mower and look up it's parts at JD to make sure what you need. Sometimes searching for the part number needed can save a bunch of time and money.

Oh where's the fun in that?

The OP said he thought he could still get one from JD, but was specifically looking for possible alternatives to the JD part, which he found substandard in quality.

 

[AndyM]

Wow - step away for just a few minutes..

Great discussion, thanks. Yes I ran into the two model issue with JD the last time - I have the pulley available for the other series if any one wants it.

If the $10 pulley looks like the the first (wrong) one I ordered the last time if it's 4" vs the 3 1/2 I need. The part number I found ( Part Number: AM107567) - is 3 1/2, but for all the reasons discussed here, I like some of the alternative options, if they are possible. For the record its a GXJX75X130391.

Here's the latest pictures;



The first show the recess into the transmission at 2.91 mm (plus or minus - hey it's a cheap caliper).

For fun, I measured the key again with an equally cheap micrometer -
not sure it improved on the caliper version but, there it is. Looks close to 1/8 if I read it correctly.

Thanks to all for the discussion - it's great.

 

[Old Machinist]

So your mower is in the early version.

https://partscatalog.deere.com/jdrc/navigation/pin/GXJX75X130391/equipment/22632/level/2/snp/MjA0NzM0OkNIQVBURVJbMTA2MTojQlVTSU5FU1NfUkVHSU9OLDU3MjQ6I0NBVEFMT0csMjI2MzI6RVFVSVBNRU5UXQ%3D%3D

The "Drive Pulley" is listed as part number M113895. That looks like a small solid pulley in the photos.

John Deere PULLEY M113895

www.greenpartstore.com

They obviously have a typo for the shaft key size for the drive pulley as it shows a strange 4.7 X 304.7mm. That would be a 12 inch long key.

The only other pulley listed is a AM107567 idler pulley. It looks more like the pulley you are working with.

John Deere IDLER AM107567

www.greenpartstore.com

Here is one of those that matches your description for $15 plus shipping and tax.

Pardon Our Interruption...

 

[AndyM]

Old Machinist

Alas I think the $15 pulley looks very much like the 4" I ordered in error, not an AM10757.

JD shows it as a 3 1/2' so I think its the right one.

Part Number: AM107567
$52.96

Product Dimensions
Weight
0.52 lb
Height
3.5 in
Length
1.1 in

If all else fails...

 

[torch]

They obviously have a typo for the shaft key size for the drive pulley as it shows a strange 4.7 X 304.7mm. That would be a 12 inch long key.

I bet it's not a typo -- If you click the description, it contains the remark " (SUB FOR M114270)" another link Square key stock kit and cross-reference taking you to a chart showing the kit is a piece of 3/16" x 3/16" x 12" key stock.

I think this is JD's way of telling you they don't supply M114270 any more, but you can buy a length of keystock that you cut to suit.

I wonder if the shaft for THAT pulley is metric too...

 

[torch]

Part Number: AM107567
$52.96

Is that in CAD or USD? How much for shipping?

I did a quick google of the part number and found several sources. Price with shipping to Canada ranges from a low of CDN$85 to a high of (sit down for this) CDN$152.90 on Amazon. Assuming you have Prime free shipping.

No wonder you are looking for an alternative.

 

[torch]

I assume this measurement is to the end of the bore?

What is the overall distance from the face of the pulley to the end of the bore? IE if you lay the top of the pulley on a flat surface, what is the dimension from the surface to the end of the bore that rides against the shaft?

 

[torch]

Of course, it's not much more to go from just a hub to the entire thing. I bet this would be especially nice in 6061-T6 aluminium:

View attachment 156188

 

[Old Machinist]

I bet it's not a typo -- If you click the description, it contains the remark " (SUB FOR M114270)" another link Square key stock kit and cross-reference taking you to a chart showing the kit is a piece of 3/16" x 3/16" x 12" key stock.

I think this is JD's way of telling you they don't supply M114270 any more, but you can buy a length of keystock that you cut to suit.

I wonder if the shaft for THAT pulley is metric too...

Ahh that makes sense. I have purchased key stock in my past to cut keys from.

 

[Old Machinist]

Is that in CAD or USD? How much for shipping?

I did a quick google of the part number and found several sources. Price with shipping to Canada ranges from a low of CDN$85 to a high of (sit down for this) CDN$152.90 on Amazon. Assuming you have Prime free shipping.

No wonder you are looking for an alternative.

I hadn't moused over the OPs name to notice he was in Canada. He will face this problem for any US suggestions.

 

[TheOldHokie]

Old Machinist

Alas I think the $15 pulley looks very much like the 4" I ordered in error, not an AM10757.

JD shows it as a 3 1/2' so I think its the right one.

Part Number: AM107567
$52.96

Product Dimensions
Weight
0.52 lb
Height
3.5 in
Length
1.1 in

If all else fails...

A lot of noise in this thread.

Consider using an off the shelf taper lock pully and a bushing to match the shaft

Taper-Lock Bushing-Bore V-Belt Pulley for SPA and Xpa Belts, 1 Groove, 95.6 mm OD

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

Dan

 

[AndyM]

Is that in CAD or USD? How much for shipping?

I did a quick google of the part number and found several sources. Price with shipping to Canada ranges from a low of CDN$85 to a high of (sit down for this) CDN$152.90 on Amazon. Assuming you have Prime free shipping.

No wonder you are looking for an alternative.

USD and yes.

 

[AndyM]

I assume this measurement is to the end of the bore?

What is the overall distance from the face of the pulley to the end of the bore? IE if you lay the top of the pulley on a flat surface, what is the dimension from the surface to the end of the bore that rides against the shaft?

That is to the end of the bore - I had trouble showing the end and the measure in one picture. Doing it as you suggested gives 23.31 mm which is more accurate.

 

[AndyM]

A lot of noise in this thread.

Consider using an off the shelf taper lock pully and a bushing to match the shaft

Taper-Lock Bushing-Bore V-Belt Pulley for SPA and Xpa Belts, 1 Groove, 95.6 mm OD

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

Dan

Always good to know all the options, thanks Dan. I see the pulley is USD $42 plus the bearing ?? so this may be a good option but likely as much or more than the OEM part. More durable maybe?

 

[TheOldHokie]

Always good to know all the options, thanks Dan. I see the pulley is USD $42 plus the bearing ?? so this may be a good option but likely as much or more than the OEM part. More durable maybe?

Cast iron comstruction and clamps down on the shaft. McMaster prices are high. You can probably find a pulley for half that. I found a matchimg 10mm bore bushimg for $11.

Dan

 

[torch]

That is to the end of the bore - I had trouble showing the end and the measure in one picture. Doing it as you suggested gives 23.31 mm which is more accurate.

Sorry, I meant the other way around, to account for the off-set. I estimated it at 26.8mm here:

 

[AndyM]

Cast iron comstruction and clamps down on the shaft. McMaster prices are high. You can probably find a pulley for half that. I found a matchimg 10mm bore bushimg for $11.

Dan

I would be interested in seeing the 10mm bore bushing - is a link possible?
A cast iron alternative to the JD version for a similar price is interesting option. Even better if a cheaper cast pully that matches' the bore can be had.