Unimat 3 Drive Pulley

[KEITH BEAUMONTParticipant @keithbeaumont45476]

I have inherited a very nice Unimat 3 . I need to replace the belt for the auto feed to the lead screw. To do this it will be easy to do if the main drive pulley on the spindle is removed. Logic tells me it should be on a left hand thread and I wonder if any other owners can confirm this. I have a photo copied hand book ,but all photos are "soot and whitewash" contrast,so cannot see any direction arrow if there is one printed.

Keith

[KEITH BEAUMONTParticipant @keithbeaumont45476]

[JasonBModerator @jasonb]

It's a Right hand thread, just put a 4mm pin in the hole between pulley and headstock and should come off with just your hand.

 

Also check your logic

Edited By JasonB on 30/01/2020 20:54:45

[KEITH BEAUMONTParticipant @keithbeaumont45476]

Thanks Jason, on both counts! I have tried in both directions by hand, but no movement. Will try again tomorrow now I know..

Keith

[John OlsenParticipant @johnolsen79199]

The O ring used for the fine feed should stretch over the main pulley easy enough, that is how I have always done it. Like the main drive belt, they don't last all that long anyway. I've changed the main drive on mine to toothed belt drive, a great improvement, but I've never improved the fine feed belt.

John

[KEITH BEAUMONTParticipant @keithbeaumont45476]

I tried to stretch the spare belt over the pulley and it snapped in the process, probably an old one ,but I am reluctant to try with the new ones I have If I can get the Pulley off

Keith

[KEITH BEAUMONTParticipant @keithbeaumont45476]

I have managed to get the pulley off OK. It gave me quite a fight and I nearly put some heat on it, not finding out that it is a plastic moulding.until it was off. I assumed it was Ali like the others ,but black..

Thanks all for your help.

Keith

[Author]

Posts