Denford Software & Machines

I have a Mk2 TDS1/1GB late model and have problems with the tension of the 'Bramer' type belt.
The handbook only notes to set at 'correct tension' and its not easy to get at through the motor door - my lathe is mounted against a wall and I seem to be suffering fron belt slip.
This is I'm sure made worse by the need to oil the shaft (back gear)below the headstock 'regularly' according to the handbook + headstock sliding gear oil applications.
The motor belt tension seems to be just the dead weight of the motor/platform when the lever is vertical.

So question is how tight should the Bramer belt be set ? and is there an easy way of checking ?

I replaced the belt when I bought the lathe - back in 1999 ! but not used that often, but much more now in retirement and lockdown.

I'm going to get another belt and clean out the belt shaft (not looking forward to that one !) and want to set upthe tension and keep a check on it more often now.

Richard B.

Hi
If your belt is of the type that is made up of linked segments, then these belts stretch a lot. That is one of their features.

I suggest you start by removing the belt and degreasing it and the pulleys.

I oil my gears with spray-on chain lube. It goes on runny but the solvent evaporates to leave a sticky coating that stays put.

Tension is not critical with poly-link belts.

My countershaft-to-spindle linkbelt is stretched or worn (it looks quite old) and needs adjustment.

Looking at the countershaft brackets from below there appear to be two slotted adjusters. Well, I assumed that is what they were but they will not move. Is there a hidden locking mechanism or is the adjustment done from elsewhere? Maybe they are just tight but I don't want to force anything until am sure these parts are meant to move.

Ideally I would like to see a drawing of the countershaft assembly - no doubt it's on this amazing website somewhere but I've yet to find it.

I hope someone can help.

Hi
Each end of the pulley shaft is machined like a two pronged fork.
These fit around the adjustment screw in the slot.
If one slot is higher than the other, the shaft will jamb.
It is as simple as that.

dazz wrote: ↑

Sun 17 Jan , 2021 6:42 am

Hi
Each end of the pulley shaft is machined like a two pronged fork.
These fit around the adjustment screw in the slot.
If one slot is higher than the other, the shaft will jamb.
It is as simple as that.

Thanks - I think someone had jammed one side, but it's now adjusted correctly. I didn't have a wide-enough screwdriver but I milled some flat down to thickness and it worked well. The old belt is now working fine with no slippage so there's no need to change it for now.

I had a similar problem over the last few days, not helped by lack of personal mobility due to knee problems.
Unable to move the adjusting screws for the intermediate pulley position I eventually unscrewed the RH bracket from the lathe cabinet.
They are allen head countersunk socket screws, I can't remember what thread but they take a 7/32 allen wrench. If you do this it's then dead easy to sort out the problems with jammed adjusters. I have milled a 1/2" square on the end so I can easily adjust them in the future.
There is a little red hermetite under the screw heads to prevent oil seepage.
I can post some pictures if anyone is interested.

Les.T.