Borroughs gauge for sale.

[mkelite]

Thank you very much guys for your supporting words. That is genuinely appreciated.
Everyone has problems relevant to them. It is just a tough time for many I guess. Hope to meet you all one day when my Elite is roadworthy. Thank you again. Best regards to all. Dave.

[MetBlue]

Sorry to hear your wow's. Keep at it and something will turn up.

If you recall we spoke mid last year and were going to meet up, then we hit full restrictions again - You're pretty close to me.
A nice run out. When we are allowed, I'll arrange to drop by. Would still love to see your Elite.

Tony

[mkelite]

Hi Tony

Hope you are very well. Yes I think lockdown is about to ease so would be great to meet you soon. All the best til then.

Dave.

[chrisw2811]

Good luck Dave. Hopefully the UK will turn a corner soon and your fortitude will be rewarded.
Best regards, Chris

[Pete Boole]

Gauge arrived safely yesterday Dave. Thanks very much!

Pete

[mkelite]

hi Pete

Many thanks again.

Best regards to all.

Maybe we can have some meets later this year then !

Dave

[Esprit2]

Actually, thinking about it, for the mechanical gauge they are both the same setting, it's different settings if using the resonant frequency method.

Sorry, I'm late to this thread...

Yes, when using a Borroughs gauge, use the same '95' tension for both the trapezoidal and HTD round tooth BLACK belts. "One size fits all" for the OEM black belts (the modern Gates Racing BLUE belts use a lower tension - 82-85).

The HTD belt's taller tooth/ deeper engagement requires less tension than the trapezoidal belt. The Borroughs gauge is 'thickness sensitive', and the HTD belt is thicker than the trapezoidal. Using the same '95' tension with the HTD belt results in a 'real' strand tension that is something lower than 95, closer to 90. I'm not sure what the ideal HTD tension would have been, but Lotus felt that whatever '95' Borroughs produced was close enough. Being able to carry forward the same Borroughs gauge and tension spec for all OEM black belts was was convenient both in terms of no new tool required, and no added confusion over which tool & tension to use.

The Lotus Burroughs gauge was calibrated using a trapezoidal belt back in the day, and it was that gauge & calibration that was carried forward into the HTD round tooth era. If your engine has an HTD belt, and you ever send your Borroughs gauge in to be re-calibrated, then send along a length of trapezoidal belt on which to calibrate it. If you calibrate it to 95 with a HTD belt (even if that's what is on your engine), then the gauge will read higher than Lotus spec by about ~5.

Both the original Borroughs, and the later cantilever Boroughs were calibrated on trapezoidal tooth belts.

Regards,
Tim Engel

[Pete Boole]

Thanks for that Tim - very informative. I'll bear this in mind when tensioning my belt.

Pete