Bridgeport/Clausing 8512 mill for sale; thoughts?

[ARC-170]

I'm thinking I'd like a slightly bigger mill than my LMS 3990. I'm looking at some RF clones, but saw this Bridgeport/Clausing for sale and thought I'd ask about it.

Here's the verbiage from the ad:
This mill is a good quality Bridgeport & Clausing Machinist's tool that is in great working order. The mill works vertically & horizontally. The mill is on a factory built stand with storage below. There are many quality drill bits and accessories included and some new in the box. The deceased owner was a scientist at both Hughes Aircraft and Northrop Grumman. The drill press/mill is in fine working order and comes with many bits & components too numerous to list. (see attached pictures for specifics) A public sale will be held in two weeks, but interested parties can make an appointment (by text) with seller to view in person prior to the sale. Cash only and all bills will be checked for counterfeit. Please review attached photos for condition and accessories included. This tool is a great size for a home hobbyist or for a small commercial machine shop. (Pick up only)

1. I'm not sure I want to deal with a "public sale", but I could be the only bidder.

2. Then there's the issue of getting it home. I'm pretty sure I can't lift this in my truck! Ha! Would an engine hoist work?

There's not much on this mill that I could find. It looks to be about the same size as an RF. Seems the 8512 was sold without a head or custom-configured for other applications. Some models were sold with a BP "M" head. This is similar to an 8520 and 8530.

Any thoughts and comments would be appreciated. Thanks!

 

[machPete99]

That is a Clausing mill in the picture, It seems to be missing the handle on the RH side of the table; maybe there was a power feed attachment.
You could potentially disassemble the mill into major components, like motor, head/ram, table, knee, base and most would be 1 man left except the column which might be 200-250#.
These mills take an oddball collet size, not R8, might be MT2 or BS7. Best to see if a collet set of the correct type is included.
Some of these came or were often retrofitted with a Bridgeport M-Head, which might use another oddball B3 collet, not sure if that is what you have here.

 

[benmychree]

B&S M heads generally came with a B&S #7 taper. The M head is fine, but does not have back gears for lower speeds.

 

[matthewsx]

I would love to have something like this. Oddball collets are not such a big deal if you can get an ER collet chuck that fits.

John

 

[Aaron_W]

The 8512 is a Clausing mill sold without the head, and this one clearly has a Bridgeport head on it which is common.

I have an 8520, so ignoring the Bridgeport head for the moment, sizewise this is actually a little smaller / lighter than an RF-31 mill drill. It is closer in size to a PM25 or Grizzly G0704, but of course a knee mill rather than a bench mill. The table is 6x24" and with the Clausing heads they weigh about 700lbs.

They can easily be broken down into manageable pieces of 50-200lbs (column / knee weighing around 200lbs, I was just able to lift this out of the truck, but that was a very poor decision that I felt for about a week). I loaded mine in parts with just the seller and no lifting equipment. I unloaded and set it up by myself with an engine hoist and a garden cart. With the Clausing heads the motor is easily separated leaving two fairly light loads, I don't know if the same is true of the Bridgeport, so that head might be a heavier load.

A plus for the Bridgeport head is it should be more robust, the Clausing heads are very accurate but on the delicate side. I'm assuming it will have a more powerful motor, the standard Clausings come with a 3/4 HP motor, I think most Bridgeports are 1-2hp. What type of collets are used would probably be worth looking into, standard on the Clausing mills are MT2 or B&S #7, with a Bridgeport head many use R-8, but I have no idea on an older one.

One of the reasons the 8520 is popular is the motor hangs off the back, keeping the height down. With the Bridgeport head on there I'm guessing you are right back at around 7 feet tall if height is a concern (the 8520 stands 66" or 70" depending on whether it has the riser block). Also combining two brands could be an issue, but considering how common Bridgeport is, the Clausing bits are probably the larger concern.

This one does not appear to have the riser block fitted so your vertical travel is limited to about 12"

For the price it could be a good option if you are considering mills like an RF-31 or PM25 / Grizzly G0704. I know a lot less about these hybrid mills, but if it has been well cared for I'd say this a step above the other options in this size class. It will be a little smaller / less rigid than an RF-31 but doesn't have the round column issues inherent to them either. It is about the smallest knee mill you will find.

 

[Aaron_W]

I would love to have something like this. Oddball collets are not such a big deal if you can get an ER collet chuck that fits.

John

Also much less of an issue if they come with a set, just don't lose or damage them.

 

[Aaron_W]

That is a Clausing mill in the picture, It seems to be missing the handle on the RH side of the table; maybe there was a power feed attachment.

Not just the handle, looks like it is missing the whole handle assembly from the right side. The powerfeed on these is usually placed on the left hand side and slips over the arbor (not sure if that is the right term?) that the crank handle would normally fit onto. Not sure what effect that would have on operation. It would definitely be worth looking around to see if the parts are there and just not assembled.

 

[projectnut]

As mentioned the Bridgeport M head machines generally came with B&S #7 collets. As such the maximum diameter drill or end mill would be 1/2" unless you go to reduced shank end mills or Silver & Demming drills. Collets come in sizes 1/16" to 1/2". They aren't cheap compared to more popular R8 collets. New Hardinge R8's usually run around $40.00 each (imports are far less expensive). B&S #7 0n the other hand run around $130.00 per copy. Again imports are considerably less expensive, if you can find them.

The missing parts may be a concern. The end plate/bearing housing and crank handle may be available through H&W Machine Repair, If it needs a new leadscrew that could easily run a couple hundred dollars. I'd do a little research on parts availability before making a purchase. It could easily cost several hundred dollars to replace the missing parts IF you could even find them.

 

[Choiliefan]

I'd pass on this mill because the way the head is mounted, you're losing 4-5+ inches of usable milling capacity due to the offset. I've had a couple of these M-heads in the past and both came with a different style mount which places the centerline of the spindle where it's supposed to be.
Here's an example from the web:

 

[Janderso]

It seems like the M head or round ram has been routinely viewed in a negative light in this forum.
I have no experience with them myself.
Aaron, the Clausing 8512 is sold without the head?