That's good to know. I'll have to keep my eyes open for another one then secondhand preferably. What did we do before eBay ?

Just looked at the BSL book, the pitch of the belts I used was 5mm and the belt width was 15mm.
 Not sure where you get your steppers from normally but they are not really that expensive nowadays, certainly mmuch cheaper than when I started out converting my manual Bridgeport 4 or so years ago. ArcEuroTrade sell the same as mine for around £50 and the next size down is about £30 if I remember correctly. Not sure the prices of other places but would think they are about the same.

Hood

I just had an email back from HPC gears. I told them originally (when I'd gotten the wrong figures) that I had 3Nm motor rotating at 1800 RPM. I gave then the min center sizes and they have done calcs. They say I'll be good for 10mm on the X and Y axis but due tot he 8:1 ration on the Z I'll need 25mm belt or I can go for a 16mm if I use a tensioner pulley with at least 180 degree wrap around. I'm guessing 10mm will handle the torque it's just the lengths needed to get around a 10 then 80 tooth pulley with center bore size of 16mm. You data obviously confirms this if 16mm works OK for you then 10mm will be OK for me. I've asked them for some prices now and the difference between 16mm with tensioner and 25mm without..

The final parts list for 2.16 Nm 1200RPM steppers on each axis is:-

2 X 24ABT5-15 24 TOOTH PITCH 5mm 15mm WIDE PULLEY TO FIT A 10 mm BELT FOR THE X AND Y AXIS
2 X 72ABT5-15 AS ABOVE FOR X AND Y GIVING ME A 3:1 REDUCTION
1 X AT5/455/10 10mm WIDE 455mm LONG BELT FOR X AXIS
1 X AT5/545/10 10mm WIDE 545mm LONG BELT FOR Y AXIS

1 X 10T10-17 10 TOOTH PITCH 10mm 17mm WIDE PULLEY FOR Z AXIS
1 X 80T10-17 80 TOOTH PITCH 10mm 17mm WIDE PULLEY FOR Z AXIS GIVING ME AN 8:1 RATIO
1 X T10/920/12   12mm WIDE PITCH T10 BELT 920mm LONG

It took a while for HPC to reply to me with some figures but the gent was quite helpful. I've now got a bigger problem they’ve quoted me £443 for the above belts and pulleys. That's a figure I just can't afford at the moment I've spoken to BSL and hopefully they are getting back to me tomorrow with a quote but it would have to at least half that figure to be do able. I've got my smoothstepper now and the customs added £16 Vat on top at the border then parcel force added another £8 for their handling costs?? Still it was a bit cheaper than buying the smoothstepper in the UK. I’m a bit gutted at the moment as the £400 + was a complete shocker. It’s my fault of course for not budgeting for it but it puts my project on a firm hold for a bit . I’ll look into worm drives or something to see if they work out any cheaper as you can get anti backlash worms and I’m feeling once I’ve got the Mill up and running I can then make some pulleys myself (wishful thinking maybe) . Downside is I won’t be able to use the mill as a conventional one unless I rig up a worm engage/disengage mechanism. Hmmm maybe a car timing pulley could be used I have a couple of them somewhere in the garage.

If BSL are much over £100 tell them thats nice, now whats the price with the discount
 I have a small HPC book I have had for maybe 15yrs or more and I still get a laugh when I look at their prices, you would think after that many years their prices would be kind of out of date but they are still more expensive 15 yrs on

I cant really remember what my pulleys  cost  for that kind of size/pitch but I think around £20, could be wrong though.

Hood

The 72 tooth ones are £46 plus vat and the 80 tooth t10 ranged from £178 to £203 plus vat depending on if I use a tensioner or not. If BSL come back with £100 or less they will get a new friend. The company I work for has ordered stuff from them before so I've gone through the company connection though I've told them it is private so fingers crossed discounts will be included.

The HPC moto is "we will never be outpriced"  :-)

No way BSL will be under a £100 but no way they should be anywhere HPC prices. What was the price you said RS was?

I can tell you what HPC would say if you told them you could get the pulleys/belts half price somewhere else, they would say yes but not the same quality of our stuff. You would probably find they are from the same batch as the half price suppliers stuff

Hood

Perfo heres the prices of the pulleys/belts I got for the Bridgeport, they are 3yrs out of date but shouldnt have gone up that much, VAT is not included
P30-5M-15MMPB/HTD £5.86 each
P60-5M-15MMPB/HTD £9.94 each
425-5M-15MM               £5.83 each
750-5M-15MM               £9.34 each

Hood

That's definitely more like the price I was expecting.
http://uk.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=0184842 this is a link for a 72 tooth T5 HTD pulley £19.64 so less than half the price of HPC at £46.83 though they say theirs (HPC) is a reduced backlash pulley. I'm not sure what the difference is between a HTD and a AT5 or ABT5  but I'm guessing the most common is HTD and these will be fine for my application. BSL are getting back to me on Monday now as they either haven't had time to work out a price or someone forgot. I'm also getting a price from anti friction components which is a local bearing supplier that also deal regularly with my place of work. I'm feeling more optimistic now I may be able to get some pulleys after all.