Securing a pulley

I probably lead a sheltered life as I've only seen pulleys secured with keys or taperlocks, I have one for the A1 that has 2 holes, one through the face and the other at 45° through the boss, both end in a groove in the centre of the hole, not sure if either of the holes is tapped yet.

The hole through the face (good job I didn't chuck my old pistol cleaning kit, it worked a treat on the holes )




The hole through the boss




The groove inside

Like I said on faceache it's probably a loose pulley used as a drive pulley, if you are that worried there's plenty of pulleys on ebay that will fit, 1 1/2 inch shaft, same as a Lister D

The hole through the face would most likely be the one that would be tapped the hole at a angle through the boss could be a oil hole for a free running pulley if you have taps just tap the hole in the face.
Regards
Chiefy.

Measuring the hole looks like it would be ¼" BSF so I've got to find a long series tap to try as all mine are too short, although ¼" BSF grubscrews seem a bit scarce so I might be going Metric as it's hidden, but don't tell anyone

Like you say it may be that you go down the metric route and 6 mm is the nearest to 1/4" B S F a man on galloping horse will never notice the difference in thread form,you can if you want drill the hole out to a bigger diameter say two thirds deep to accommodate the tap holder then tap the bottom bit.
Regards,
Chiefy.

Grubscrews ? - try here

https://www.ba-bolts.co.uk/index.html

So would it be good engineering practice to drive the load through the grubscrew?, I was just thinking of the shearing force on the threaded portion.

Lots of pulleys were driven by a screw only, excepting where they fastened onto the shaft a flat was filed on the shaft for the screw to fasten onto,with modern allen keyed grub screws they are designed to screw down straight on to the shaft and they bite into the shaft they are high tensile,this can present a problem when you want to remove the pulley because of the burrs they raise , so its back to a small flat on the shaft.
Rgards,
Chiefy.

chiefy wrote:Lots of pulleys were driven by a screw only, excepting where they fastened onto the shaft a flat was filed on the shaft for the screw to fasten onto,with modern allen keyed grub screws they are designed to screw down straight on to the shaft and they bite into the shaft they are high tensile,this can present a problem when you want to remove the pulley because of the burrs they raise , so its back to a small flat on the shaft.
Rgards,
Chiefy.

Excellent, thanks for the explanation, although I consider myself fairly practical I don't have an engineering background (sparky by trade) so I normally leave that stuff to the fitters at work

Slight drift OT but I have noticed craft/trade apprentices are not given the skills that were taught to the previous generation, maybe it's because modern equipment is built to higher tolerances, but lower cost with less serviceable parts so the skills such as bearing scraping are no longer needed (or taught). I've noticed the same in my own trade, in the 70's, contactors (big relays!) could be overhauled with manufacturer supplied service kits of new contacts, springs etc., but modern ones are not designed to be dismantled, just dumped and replaced with a complete new unit.

Woodsman wrote:Grubscrews ? - try here

https://www.ba-bolts.co.uk/index.html

Thanks for the link, looks like the Petter will be staying Imperial and I will find a use for the Imperial Allen keys

Good looks like a successful outcome and i agree that modern day apprentices are not taught all the old skills i think that modern day thinking is if you have a problem with any kit chuck it away and buy another!!!.
Regards,
Chiefy.

I don/t know of any modern day apprentices these days this seems to of all fell apart so our skills have all gone to sleep such a shame

The company I retired from two years ago takes on two apprentices a year, they do day release at college and the service engineers, of which I was one and a five year time served apprentice in mechanical engineering, pass their knowledge onto them, they are taught electrical/electronic engineering, mechanical engineering, how to use tools correctly and at college they learn how to use lathes and milling machines. Most of those that joined the company had no idea but after three years have become able to carry out the work safetly and proffesionally.

Maryalice

It's not only pulleys that can have unexpected grub screws. The bearing went on one of our farm machines so after taking off the guards and all the circlips apparently holding it in place  out came the pullers to get the bearing off. No luck and after eventually hammering and cracking open the bearing housing I got the outer ring off but the inner part was still stuck to the shaft . But then I could see that the bearing centre was not just a press fit but secured by three grub screws to the main shaft.... ouch, and now we need a new bearing housing

Some of the plummer blocks have a grub screw in the centre boss piece this to stop the shaft moving lateral the ones i have seen have had only the one grub screw three sounds overkill to me with these you would need to file three flats where the grub screw bites into the shaft or you would have a hell of a job removing the shaft if it became necessary for maintainance .Regards,
Chirfy.