New Project - Benchmaster MV-1 mill

AR1911 said:
I assume you are asking about removal of the bearing races. The race ID is just smaller than the seal bore, which gives you something to press against. In this case, the OE felt seals are between the casting and the race, so you are actually pressing against the seal. You make a tool with some 1/2 all-thread. Make disk about 1/2" thick that barely slips in the outer bore, and cut a recess so it won't damage the seal. You end up with a shallow cup with a 1/2 hole in the center. Then you need a short cup for the other side that is bigger than the bore. Add two nuts for the alltread and squeeze it out.
Repeat for the other race, with different size cups. If you have a large collection of "materials" then you can probably cobble something from scrap.
Click to expand...

Thanks AR1911 - I guessed something like this, but am more than happy to get confirmation.

mfs
 
Nice machine! I should like to have an similar!
 
Thanks Torbo

At this point I just lack the pulley. I dropped it off at a friend's shop to be repaired where I chipped the edges taking the head apart. If he hasn't got to it yet, I'll pick it up. I bought some low-temperature aluminum brazing rod last weekend that may be just the ticket for pulley repairs.
 
I seem to remember an old machinist from WW2 days, when I told him about my Benchmaster he said something about the bearings being hard to get in and out. Is my memory right?
 
Not really. No harder than changing front wheel bearings on a car. The lower bearing does require a press.
Both races require an improvised puller made from all-thread and scrap.
 
I see occasional references to 'precision bearings' for the BM MV1's main spindle. Is there a different set of bearings with closer tolerances?

Martin Sl.
 
They were hand-etched with the date and other marks as high-precision bearings are, but I have no way to confirm that were anything but standard bearings with the date added. I did take care to orient the lower bearing to the spindle in the same place.
This has been discussed on the Yahoo group. A number of people have used standard, automotive-grade bearings with satisfactory results.
 
Got the pulley back, welded up. Once I turned the excess off you can't see the repair unless you turn it over. I did not remove all the weld on the bottom.

Reassembling the spindle was simple at this point. I did not add spacers under the bearing races (to compensate for the missing OE felt seals). The spindle sits about 3/16" higher in the head than before, but the seals hit the correct surfaces and it turns freely.

At this point it is complete except for motor and switchgear. I have several motors to choose from. Most likely I will use a 3/4 HP Marathon with a drum switch. It came from a South Bend 9" lathe of the same period.

IMG_5727.JPG
 
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