Comparison of the capabilities of the Clausing 8520 versus the 8530 ?

[Packard V8]

On another forum, I saw someone desperately seeking a Clausing mill. I have an extra 8520 in decent condition, so I offered it to him. He was ecstatic and swore he'd buy it on the spot. As it happened, I was away from the shop for a week and when I returned, he'd recanted. Someone convinced him the machine he had to have was the much improved 8530. Since this guy was only going to be working aluminum and plastics, is there really anything the 8520 couldn't do that would require an 8530?

Another thought, since they're many fewer 8530s around, how much more would one expect to pay for an 8530?

jack vines

 

[Latinrascalrg1]

Man if you weren't on the opposite side of the US I would jump on your offer, at the right price of course!

 

[Packard V8]

Man if you weren't on the opposite side of the US I would jump on your offer, at the right price of course!

You're only a couple of thousand miles from this 8520. FWIW, I rebuild engines and ship them dock-to-dock all the time. The most difficult part is getting it crated and on the truck. Once the wheels are rolling, a few more miles aren't prohibitively expensive.

jack vines

 

[Briney Eye]

On another forum, I saw someone desperately seeking a Clausing mill. I have an extra 8520 in decent condition, so I offered it to him. He was ecstatic and swore he'd buy it on the spot. As it happened, I was away from the shop for a week and when I returned, he'd recanted. Someone convinced him the machine he had to have was the much improved 8530. Since this guy was only going to be working aluminum and plastics, is there really anything the 8520 couldn't do that would require an 8530?

Another thought, since they're many fewer 8530s around, how much more would one expect to pay for an 8530?

jack vines

Depends on what he's doing. The 8530's have a beefed-up knee, more capacity over the table, and a two-speed gearbox on the X axis.

My 8520 had been fitted with the factory power feed (variac, universal motor and friction clutch) but, astonishingly, still had the original crank and dial in the cabinet. Since the power feed was no longer feeding and seemed pretty clunky anyway, I just reinstalled the original crank and dial after I had cleaned everything up and replaced the bearings. One of these days if I get tired of cranking maybe I'll drag the old power feed out and see if I can get it running again, but I think I'd be more inclined to buy and adapt a new "Servo-style" one.

 

[Aaron_W]

The most obvious difference is the manual feed, the 8530 has a 2 speed feed on the right side offering 1-1 or 4-1 travel speeds in the X axis. The same unit is found on some of the Clausing horizontal mills.

The added Z distance comes from a 4" taller column on the 8530, the 8520 could be fitted with a 4" spacer block giving it the same height. I'm not sure if the 8530 actually has a taller column or just got the spacer as a standard feature. Stock the 8520 stands 66" tall, the 8530 70", so if your 8520 stands 70" tall then it has the spacer.

Supposedly the knee is improved and heavier on the 8530, but can't say for sure how much difference it really makes as I've never actually seen an 8530 up close. The only 8530 I've seen listed for sale sold for $2500, the same price I've been seeing 8520s listed for.


Personally if in the situation of being able to choose I could see maybe paying a little more for an 8530, but I can't see the differences being enough to pass on a perfectly good 8520 in the hopes of eventually finding an 8530. There seem to be a lot more 8520s out in the wild, the 8530 came along later and were a more expensive machine so it makes sense that far fewer were sold.

 

[Aaron_W]

Following up on this as I looked into it more.

The 8530 has 15-3/8" spindle to table vs 11-3/8" on the 8520. There was a 4" spacer block available to the 8520 giving it the same spindle to table distance as the 8530.

This comes from a Clausing catalog identified as 1961 so would pre-date the 8530 by quite a few years as I think the 8530 came out in the late 1960s.




Examples of machines with the standard (short) column cap on the right, and one with the 4" riser (tall) on the left. The main identifying feature is the distance between the seam above the Clausing tag on the column and the head swivel mount. (photos from CL ads)




I've not seen an 8530 up close, and can not find any photos of a quality to determine whether or not the 8530 actually has an entirely new column or more likely just includes the riser as a standard feature. An entirely new column casting seems like an unnecessary expense. Of the 8530's improvements this riser seems to be the most useful, but not exclusive to the 8530.

Looking at the parts breakdown in the parts list for each, and photos of both the 8530 has a different knee design with a pronounced step. 8520 on the left (without riser block), 8530 on the right. These photos also show the 8530s 2 speed handle on the right side of the table. (merged from photos at lathes uk).

 

[wa5cab]

I see another difference that doesn't appear to be a consequence of merging two photos. The table lift or jack screw visible in the 8520 photo has a nearly conical shaped lower support that sticks up from the base. The one shown under the knee of the 8530 is apparently the same diameter all of the way down nearly to the base.

 

[Rootpass]

8530 from a completed eBay add.

 

[Aaron_W]

You can also see this in the parts lists. So the 8530 definitely has a different knee assembly, but it would take someone who has used both to say what improvements come from the change. More stability, more durable, ergonomics, easier to repair?

8520


8530

 

[Rootpass]

I don’t believe I’d turn around for the difference if you had the riser block for the 8520. I don’t really care for the power feed that came on the Clausings. It’s better than nothing but there are plenty of electric diy installs on the internet.