Compressor A belts

[RonA]

The A belts on my compressor have been showing signs of stretching & after several adjustments, there was no adjustment left so I thought it’s time for new belts.
The originals were clearly marked A46 so I ordered a replacement set from a reliable source.
However on arrival the new A46 belts seem no shorter than the originals. Is there any variation between different manafactuters.
RonA

 

[slim_boy_fat]

Is there any variation between different manafactuters.

I wouldn't have thought so.

 

[Greeves246]

Got belts for a lathe from https://simplybearings.co.uk/shop/Belts/c4601/index.html

 

[500e]

Got 2 for a drill same No's no adjustment had worked for 20 years with originals

 

[rikrobson]

But you said the originals had streched, so the new ones would need to be shorter or they will be over sized like the original ones

 

[8ob]

With anything running multi belts you need to source matched sets, there is a + or- tolerance which can amount to 6mm belt length difference not including variations in width. Normal off the shelf belts cause havoc where the "shorter" belt gets destroyed doing all the work until its worn in/knackered. A decent belt supplier can source matched sets off the same production run.

Bob

 

[timgunn1962]

Modern belts don’t usually seem to stretch much. What usually seems to happen is that the belts wear on the surfaces of the vee and the effective pitch length gets a bit longer. The pulleys can also wear, reducing their effective diameter. Usually, the wear is worst on the small pulley which, on a compressor, is the motor pulley and cheap/easy to change.

New belt and, if needed, new small pulley should see you right. Cast Iron pulley and taper lock bush is the best way to replace the pulley.

Compressors are usually a right Mildred to tension. Using a moulded-notch spa/xpa belt makes it easier to roll the belts off and on without moving the motor: not the “correct” way to do it, but works for me.

 

[Bravheart]

The A belts on my compressor have been showing signs of stretching & after several adjustments, there was no adjustment left so I thought it’s time for new belts.
The originals were clearly marked A46 so I ordered a replacement set from a reliable source.
However on arrival the new A46 belts seem no shorter than the originals. Is there any variation between different manafactuters.
RonA

How long you had it? Sounds like the last owner chucked a couple of belts on to get it out the door rather than fitting the proper ones.

 

[RonA]

To answer some of the points raised.
The compressor was put together myself, after buying separate vee twin compressor, Reservoir cylinder, brooks motor & then fitted with safety valve & auto cutout/in switch. The original vee belts when fitted still had a fair amount of adjustment available. The set up although somewhat long in the tooth has performed well & was built in stages when my finances were not as plentiful.
Timgunn’s comments about belt removal struck a chord. The compressor unit has a cast iron pulley & the motor has one mentioned by tim i.e a patent taper lock design (can’t remember who made them). Whilst I doubt the one on the motor will have worn I am beginning to wonder about the cast iron compressor pulley. I think an in depth inspection is in order. The belt tension is adjusted using the slots in the motor chassis & tethered horizontal bolts to push the motor into place before to achieve belt tension before tightening down the motor chassis holding down bolts.
I think I may be order some A45 belts to bring it back in adjustment range
Thanks for all the comments
RonA

 

[Bravheart]

To answer some of the points raised.
The compressor was put together myself, after buying separate vee twin compressor, Reservoir cylinder, brooks motor & then fitted with safety valve & auto cut/in switch. The original vee belts when fitted still had a fair amount of adjustment available. The set up although somewhat long in the tooth has performed well & was built in stages when my finances were not as plentiful.
Timgunn’s comments about belt removal struck a chord. The compressor unit has a cast iron pulley & the motor has one mentioned by tim i.e a patent taper lock design (can’t remember who made them). Whilst I doubt the one on the motor will have worn I am beginning to wonder about the cast iron compressor pulley. I think an in depth inspection is in order. The belt tension is adjusted using the slots in the motor chassis & tethered horizontal bolts to push the motor into place before to achieve belt tension before tightening down the motor chassis holding down bolts.
I think I may be order some A45 belts to bring it back in adjustment range
Thanks for all the comments
RonA

Sounds like a plan, as you built it yourself are you sure both pulleys are A size spec.?

 

[RonA]

Sounds like a plan, as you built it yourself are you sure both pulleys are A size spec.?

Yes the pulley & vee twin comp were a complete unit with identical vee form slots to the motor pulley
RonA