Atlas Horizontal mill

Just for MY information, did you use the instructions from the MMB manual in the Downloads section?

:frog:
 
34-40,

Sorry. My trifocals sometimes get in the way. Flustered
 
trifocals huh?... my bi's are enough for now I hope.

Got my new belt from NAPA, and it says on the back - made by Gates with the Gates number also right there!
Hope to install it tomorrow night.

Thanks for the help guys!
 
Yep, I used bifocals for about 20 years.
 
My old belt was really torn up due to extreme misalignment of the countershaft (discussed in another thread). I measured the existing belt and it was .625 wide and .350 deep, and a length of 28 1/4".
The pulley only seems to be about .610 across the top.

The 5L profile is 5/8 across the top and 11/32 (.344) high (http://www.vbelts4less.com/V-Belt-Specs_ep_45.html) and they also refer to it as a B series on that page.
Yet on another page they list "classic B" (http://www.vbelts4less.com/Classic-B-Section-V-Belt_c_25.html) as 21/32(.656)

I chickened out on the spindle work and bought a link belt:

Fenner Drives PowerTwist Plus 5/8" B Link V-Belt
  • Profile shape: Vee
  • Profile size: B/17/5L
  • Color: Red
Again, mixing B and 5L. Even though they call it a 5L alternative, it is about .654 across the top, or 21/32 like the B specification. It seems to ride high in the pulleys for my taste. Seems to pull fine so far.
Link Belt.jpg

Their chief competitor, Jason Industrial, has this picture in their brochure:
Jason Belt.jpg
so maybe that's how they're supposed to ride.

There's another factor at play as well. Lathe.co.uk has this quote:

"The drive belt was an unusual size of steel-band reinforced V belt - which has caused some replacement problems in recent years; one solution is to use a "Wedge belt", a deep-sided, heavy-duty version of the standard V belt. "

I went wandering off through Colvin, Machinery's (3 different versions) and the web and now I'm confused even more. The wedge version is too deep. Whichever belt is to be used should be a (belt)X version, as they are cogged like my original and can handle smaller pulley diameters. Machinery 24 lists minimum pulley diameter for B belts as 5.4 inches, and a BX belt as 4 inches. If I look at the pulley dimensions, the top of the pulley measures about .610, which is near the recommended .600 for a 5V series belt, but the 5V series belts are way too deep at 17/32". And the pulley groove is too shallow at .395 or so versus .750 min for the 5V. The B/BX belts call for .730 pulley groove depth so the pulley is way off there as well.

The 5L belt shows a pulley groove depth of .580, which is closer to the .395. The 5L does allow a minimum pulley diameter of 3.5".

I don't understand what the old belt was, unless it was something totally custom. The small countershaft sheave seems to have an included angle of 30 degrees, which is narrower than any of the standards as well.

So, after all that, the 5L280 sure seems to be the only modern equivalent..... And maybe the link belts are OK as well, based on the pictures. Does anyone who has run the link belts on the mill for a while have a comment?
 
I've run the green link belt. Got it from the national cheapy tool store for 1/4 of the price that you see it on ebay.
I found that it runs right to the bottom of the pulley V.. But it may be that my pulleys are worn too??
I hope to get into the shop tonite and swap in the new belt. So I'll know how this new belt fits. When I picked up my mill there was no
spindle belt, the P.O. had cut it away as it was pretty raggedy and he had intended on replacement. So I don't have any idea how well
it ( old belt) fit into the vee.
 
The national cheapy store only lists a 1/2" belt (4L, A, etc...) at this time.
I did exactly what you say in your next to last sentence, but I did have the belt to measure and the one on my mill was clearly 5/8 wide.
 
Success! I got the spindle out, and the bearings aren't to bad off. Dry as the Sahara in the bearing case but the bearings themselves still had lube.
I also trial fitted the belt into the pulley after washing it and it fits just perfect.

SO grab yourself a copy of the MMB and read it a couple times to get familiar with the locations and the pieces and take your time, it is probably harder to reassemble and holding all the parts in alignment.

I should be able to get the spindle back in with clean lube and then go into the cleaning and reassembly of the table drive system repair, the new gear showed up also.
With a little patience from the wife I'll get some shop time this weekend.. :shhh:
or I'll be spreading loam for the new lawn..:digger:
 
You are ahead of me... I got the spindle out, didn't like the feel of the dry bearings and purchased NOS replacements. No mill refurb work this weekend for me, I have a welding project to get done: Loading ramps for an 18x8 trailer that took me 3 years to build.

Spiral_Chips
 
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