Spindle speed range or lack of it!

[creep_pea]

Hi

My Boss 6.1 doesn't get the full speed range, it will only go down to about 100rpm and up to 300rpm in the low box, 900 to 2500rpm in the high gear.

Any ideas what might cause this or if it can be adjusted?

I've took the top cover off and it was full of thread type bits, off the belt I presume but the belt doesn't look to that bad, could the belt cause this?

Cheers

Chris

[HuFlungDung]

If the variable speed belt is worn (narrower) this could be the cause of not enough range. When you run the shift mechanism all the way in or all the way out, the belt should come right to the edge of one pulley or the other. Do this with the motor running.

[machintek]

Could also be a misadjustment of the screw (speed plate pivot) on the top of the belt housing.
I also had a machine where the new bushings were not epoxied in place. The key got loose, slipped down. the plastic bushing turned, locking the key into the wrong place, thus limiting the range of the travel of the vari disc. I have had some real brain teesers, I have had to fix. Pulling it apart usually allows one to see cause and effect as to why something is not working correctly.

George

George

[creep_pea]

Thanks for the replys, I think it probably is the belt as I took it off and the underside of it looks like it has been cut away or something.

Tried adjusting the speed pivot plate screw but it scared me as it seamed like it was going to chuck the belt off, the spindle surging faster and slower when i altered it for more speed. So it's probably at bit of both but the belt been the main cause I think.

Anyone got a part no. for the belt or a link to a shop that sells them, I think I've read before that these are a special bridgeport only part due to the angle, is this correct.

Thanks

Chris

[creep_pea]

Hi

Is this the right belt it's off a manual machine but I'm guessing they share the same size belt.
http://www.alternativemachinetool.co...b1d28d5814a1c0

Anyone know of a place I can get one in the UK.

Cheers

Chris

[creep_pea]

Anyone know?

[colin1544]

Originally Posted by creep_pea Thanks for the replys, I think it probably is the belt as I took it off and the underside of it looks like it has been cut away or something. Tried adjusting the speed pivot plate screw but it scared me as it seamed like it was going to chuck the belt off, the spindle surging faster and slower when i altered it for more speed. So it's probably at bit of both but the belt been the main cause I think. Anyone got a part no. for the belt or a link to a shop that sells them, I think I've read before that these are a special bridgeport only part due to the angle, is this correct. Thanks Chris

Hello Chris have you tried Terry Braithwaite up in Yorkshire he rebuilds Bridgeports standard turret mills as well as CNC mills and he will send you a genuine replacement his phone number is 01262 606691 Cheers Colin

[creep_pea]

Thanks Colin, I'll give him a ring tomorrow.

Got a price of Steadman M/C Tool Services (WWW.SMTS.CO.UK) today and I've found a cheap belt on Ebay but it's from the US and I'm not sure if it will be the right one.
Here's a link
http://cgi.ebay.com/ws/eBayISAPI.dll...MakeTrack=true

Thanks again

Chris