Myford countershaft and belt help

[patgasParticipant @patgas]

Purchased a nice original first lathe Ml7 I’m changing the belts oiling/cleaning etc.

Belts- secondary is a standard 23inch locks 13mm wide,

Primary- 34.5 but narrower ? Is this correct and is it a 12mm I need, planning on cogged belts.

Oh and primary shaft is worn 🥲 any one have a un scorn one they would part with, let me know.

Thanks

[HopperParticipant @hopper]

The headstock spindle belt is a standard A-section belt (A23), which is nominally 1/2″ or 13mm wide. The problem for a beginner is that you need to remove the lathe headstock spindle to change the belt, which is best not attempted without suitable experience and knowledge. Much simpler to buy a good quality link belt that as the name implies can be joined at one of the links and so can be wrapped around the headstock pulley in situ. Fenner is one good brand of link belt that is popular. Avoid the cheap link belts as the plastic is know to slip on the pulleys under load. Others on here with experience of link belts on Myfords will be able to tell you more.

The motor belt is narrower Z section belt, which can be a bit tricky to source. I just run a standard A section belt of the right length there. It rides up on the pulleys a bit but it works. I dont remember the exact length but the motor platform is moveable to adjust tension so either 34 or 35 will probably work. In the UK you should be able to source the correct Z belt.

Good luck finding an unscored used countershaft! They all do it. Myford Ltd/RDG might sell new ones if you check their site. Or you can make one from a piece of bright mild steel of the same diameter if you can cut the keyway in it, probably not a beginner project if this is your first lathe.

EDIT: Myford have them new for 30 Quid here https://www.myford.co.uk/product-category/myford-ml7/motorising-assembly-myford-ml7/

You should also renew the two Oilite bushings the shaft runs in if you put in a new shaft. That said, they will run a long time with clapped out shaft and bushes there with no big dramas.

[patgasParticipant @patgas]

Thanks for the swift reply, so all stripped ready for belts, easy enough. I have play in shaft/olite so was planning on replacing as I’m going through it. I take it will be noisy if left, I will possibly bite the bullet and buy new as it’s in bits. I think a z belt is like 10mm I can fine a cogged belt in 12mm, might be ok option.

Wishfull thinking on the shaft 😊

 

[HopperParticipant @hopper]

Yes, new shaft is not cheap, for what it is.

Standard belt specs are online if you want to check. Most belt suppliers should be able to tell you what you need if you have the measurements.

[noel shelleyParticipant @noelshelley55608]

I would not worry about a cogged belt, the pulleys are not so small and while some here like link belt I would not use it especially on a ML7 where a belt is easy to change. You will notice that the headstock bearings may still have shims in, if so do NOT mix them up, replace in their original position, depending on wear they may have all been removed. Good luck. Noel.

[patgasParticipant @patgas]

Headstock bearing shims noted, these are original and all in perfect condition with zero play, one positive. I take it the people forget the oil nipples on the shaft hence the wear.

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