Hello John. V8Eng and I were discussing Tri Leva maintenance the other week.

1. I was adjusting those thumb screws over the weekend. Those thumbscrews have a slot milled in the end that cup the pulley blades (see V8Eng pictures above).
2. You thus need to push the pulley blade from the front of the unit, since a spring holds the blade within the slot when that lever is in the up position.
3. Whilst the blade is held back (under spring tension), simply twist the knurled head to get the require pulley-on-belt tension once that lever is depressed.

Hence do NOT attempt adjusting the thumbscrews till the blade is away from the slot – you will simply bugger up the thread as V8 has alluded to!

Ask again here if I can help any more – the chaps on this forum have been very helpful to me over the years

Hope none of the following is teaching Granny how to suck eggs and sorry if it is!

Was the spindle running ok before you changed the belts?

If it was then have you reassembled the shaft parts and set things up according to the manual?

May be a silly question: but did you make sure the bearing caps were put back as they were originally and that none of of the bearing shims were lost or misplaced during the belt change?

Hope you realise that the belts normally should slip until the relevant lever is pushed down, if the shaft is that tight then I would not be attempting to run the lathe until it is sorted out.

Maybe somebody can come in on here with more experience of these matters, mine is very limited.

Edited By V8Eng on 17/04/2019 14:15:40

I've owned a Tri Leva since the mid eighties and have changed the belts about every five or six years. Once you get the hang of the adjustment process, it all works well. The speed selection levers double as clutches so stopping, starting and speed changing (between the three speeds available) is almost instant. Engaging & dis-engaging the back gear is a bit of a pain, it's more difficult to raise the spindle/ belt cover on a Tri Leva, so it's easier to leave it in position and just use the cover behind the bearing as Nottingham intended.). I have an Allen key with a shortened business end, just for this purpose.

It is important to tension the motor drive belt first because that will affect the distance between the three drive pulleys and the spindle. I now use one of the segmented, cogged belts & it has been completely satisfactory. To get the right grip, this belt should be tensioned so that there is no slack but it's not tight enough to pull the driving (top) spindle down appreciably.

Having done this, with the other three belts slackened right off, adjust the tension of each belt until it just grips. This may require a lot less tension than you expect. The belt tension should be just about discernible as the speed selection lever is pulled down. If it slips when you're taking a normal cut, just tweak it up slightly.

With the motor running and with all three levers right up, the main spindle (mandrel to some) should not revolve at all.

Hope this helps.

Andy