How Much To Rebuild Clausing 8520 Head?

markba633csi

Mark Silva
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Supposing I was lucky enough to snag one of these and the spindle bearings turn out to be shot, how much work and cost to replace? What if the spindle itself is shot? I imagine there are NO parts available except used- right?
Mark S.
 
Yep I saw that one but it looks pretty clapped. I'm limited by size mainly. Can't do a Bridgeport. Maybe a Millrite or an Index #40.
Mark S.
 
Klatu. Barrada, Nicto. LOL..

Anyways, back to your question(s). I have an 8520 and have seen a couple folks "rebuild" the head. The bearings are available and I don't remember them being totally outrageous in price.
No more than you'd expect to pay for a precision bearing. The hard parts are the fine feed gears. They aren't available new to my knowledge, but I think Boston gear has some acceptable substitutes.

There was a couple "pages" around the net of folks doing the overhaul / service, if you need to see them I can try to hunt them down again. Lastly, if you can find a 8520 and can work it out, grab hold of it!
I thoroughly enjoy working with mine and it was expensive for my pockets, but once you get past the price it is worth every cent! It's very capable for it's size.
 
Thank you. Gort thanks you too. Now I can see the procedure is just easy/hard enough that a person without a lot of skill might botch it in a few spots. Have to check carefully/ask alot of questions when buying one.
Also looks like the prices have more than doubled since that article was written. Yikes.
Mark S.
 
That was a very well written document that I hadn't seen before, so thanks for that!
I've been considering doing this job on mine as I heard the bearings once during this past winter. Once it warms up it's fine tho...

I think doing the service is "do-able" by most persons of average skill when approached in a systematic series of steps, things like the tooling and pullers can be overcome with some ingenuity/creativity.
Whenever pushing or pulling bearings and shafts, alignments are critical, but careful observance and taking the time to watch / measure misalignments can help ensure success.

I actually saved the document so I can use it in the future. I may also look into the other website mentioned in the write-up..

Good Luck in your search, I'm hopeful you can get a 8520 mill, then you'll begin searching for tooling, or DRO's.. or rotary tables.. or.... more tooling.. or.... LOL..
 
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I bought my 8520 ,unseen, a few months ago. It is in beautiful shape. The felt in the way wipers are not even discolored. But the belt guard got broken and the pulley shaft was bent during shipping. I made a new shaft and when it bothers me enough I'll take the motor bracket off and braze things back together. The fine feed is smooth as silk but the other hand feed on the quill seems to take more effort than it should so I don't know.
 
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Rootpass, it sounds like the quill pinch bolt might be a bit too tight. You could back it off a bit, but it is a very touchy adjustment.
 
I didn't even know that was an option. I'll look and see if that is something I think I can do without messing something up.
 
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