Tensioner thread size

[David Merritt]

Hi all.
Does any one out there know what the thread size is for the tensioner nut (CV0221) and screw (CV0222)?
I suspect it is 1/8 BSPP but would like conformation before I run a tap and die over the threads as currently they are very tight.

Thanks

David

[Adrian Harris]

Unless it's a bought-in part, I doubt very much it would be an imperial thread.

Adrian.

[David Merritt]

Adrian,
The thread is either 27 or 28 tpi and just under 10mm in diameter which is much to fine for a metric thread of that size.
The fine M10 thread has a pitch of1.25 which is around 20 tpi.
I say either 27 or 28 tpi as my eye sight is not that brilliant at that level of detail and 27tpi is 1/8 NPT and 27tpi is 1/8 BSPP. To very similar threads.

David.

[David Merritt]

Correction 1/8 BSPP is 28tpi.

David

[David Merritt]

Dining further there is a M10 thread with a 1m pitch which could be the thread size as it would be around 25 -26 tpi.

Must get better glasses.

David

[Sean-Armortek]

The thread is M10 x 1.0
If you're coming to the open day tomorrow, bring the part, and I'll run the correct die over it if you would like.

Off the top of my head, they were a tad tight for the first 10mm or so, but with a little lubrication, the nut should still pass over that initial area and run freely from there onwards. The nut will never run on that initial section of the thread once assembled, as it sits much higher up towards the hex end.

[David Merritt]

Sean,
Thanks for the information and the offer to sort the problem, unfortunately I will not be attending. I have obtained the required tap and die so will be able to sort the problem.
The stiffer the thread is, within reason, the less likely it is to move under load.

David

[Sean-Armortek]

The stiffer the thread is, within reason, the less likely it is to move under load.
David

This was my reasoning also during production.
Was a part that definitely required a lot of regular offset adjustments in order to keep that long thin thread in check iirc.

Atb with the rest of the build.

[Aaron Cheng]

Have you tried inserting it from the other end? On my assembly, inserting the adjustment screw ball end first causes the threads to bind before a full revolution, but going the other way and inserting the hex end in first is easy to do by hand.

-Aaron