*new to me* bench drill press. Help me learn about it?

[Ken from ontario]

I ordered bearings which are 5/8" id and 35mm od that have the correct 11mm height. It doesn't seem as mysterious as some have made it sound. there is a high likelihood that I'm missing something. I'll find out in a few days.

Thank you for keeping it real, the local bearing supplier in our small city claims they can get any type of bearings as long as they know the part number or the actual dimensions, if there's an older/ hard to find type, all they ask is to bring the actual bearing to the shop so they can measure it themselves.

 

[NC Rick]

Nice machine Rick.
I’m on the hunt for something like that.
Envious!


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I hunt often, score a kill seldom.
I have been known to become over stimulated and loose objectivity. I'd say it was a fair deal. I'm still shocked at how good this machine is. I'm near bare cast iron with now and have only found a missing handle and a small crack in the base that I can repair.

 

[NC Rick]

You have to love how they overbuilt the old stuff. It has more bearings than some modern mills.

I'm not sure I would call this "over built" the castings are nice and clean, quite smooth with very little to no filler used. The extra bearings to isolate the belt torque are good but I wonder how much of that is dictated by the small size and maybe limited bearing choices of the time? It is a well made light duty machine. I can't find any details of what may have been special with the spindle bearings but I don't see any provision for preload to indicate them being a set of angular contact bearings. I ordered deep groove shielded bearings to go in there. I intend to run this in the 3-4,000 rpm range for small drills. Maybe higher if it runs true enough to run a #60 carbide drill. I broke 3 of those in my pencil grinder the day before I "Pulled the Trigger" on this drill press

 

[DavidR8]

Is the table raised and lowered via a rack and crank mechanism?

 

[NC Rick]

Is the table raised and lowered via a rack and crank mechanism?

Dave, nope. Gravity efficiently lowers it very quickly and it is reliant on the ingenuity and arm of the operator to go back up. Because it is a 13" table top drill press, I don't see a big problem. I have an old palmgren index table but I just don't see that getting used with the Bridgeport being so close at hand. I'll only use a small vise or my 5c collet fixture and in the case of the fixture, I won't be moving the table. A lot of this machines future in my shop will depend on how true it will spin a small drill. I'm hoping for under 0.0015 tir.

 

[NC Rick]

Oops!

raw castings are soaked in Phosphoric acid ATM.
i TIG brazed the small crack in the base where the column clamps After grinding the crack mostly through.

any ideas how I can make the machined unpainted cast surfaces look good after painting?

 

[NC Rick]

I'm new here and hope I am not blathering on with this. I'm learning. I found a great color match for the original paint using a Sherwin Williams code I found on the vintage machinery forum. My bearing investigators have been enlightening. I did not pre-measure to precision as I assumed the spindle shaft was a nominal 0.625" which it is not. The stock bearing has a 0.0005" press fit to the shaft and the standard 5/8" Id bearing slides on with 0.002-0.0025" oversized id. I cut the original bearing open and feel confident that my choice of a deep-groove ball bearing will be okay. I don't have a lot of worry about using retaining compound but I'd like to aim for better concentricity by either using a 0.001" shim or knurling and skimming to the correct fit along with retaining compound.

 

[NC Rick]

Thank you for keeping it real, the local bearing supplier in our small city claims they can get any type of bearings as long as they know the part number or the actual dimensions, if there's an older/ hard to find type, all they ask is to bring the actual bearing to the shop so they can measure it themselves.

Ken,
I may be going from "keeping it real" to going off the deep end! The original bearings from the 30's is strange. The shaft isn't 0.625" but 0.623" and the outer race has an on-size fit. I need some kind of press fit on one side of the bearing. I don't want to use Retaining compound as I'll run this press at 4,000 rpm often and I'm concerned about bearing accuracy and heat transfer.
so, down the rabbit hole I have jumped. I'm planning to have the shaft built up with hard chrome and O.D. ground to size to utilize the bearings meant for a 5/8" shaft.

 

[Choiliefan]

Who is doing the hard chroming and finishing to size?

 

[Ken from ontario]

I understand your concern about heat transfer but after reading product info on the retaining compound #680, it sounds like it might just do the trick, maybe some of the experienced machinists members can chime in and tell us whether it would work for your application.

OTOH, if you know a place that does the hard chroming at a reasonable price, it might be a better option but I still would research the retaining compound option a bit more, I've heard positive comments on them.

Top Pick Loctite® 680™ is a high strength, high viscosity room temp. curing adhesive used to join fitted cylindrical parts. It fixtures in 10 minutes and provides a shear strength of 4,000 PSI. Capable of filling diametral gaps up to 0.015". Loctite® 680 allows relaxed machining tolerances, and replaces clamp rings, set screws, and snap rings. Gives best resistance to dynamic, axial & radial loads. Recommended for retaining shafts, gears, pulleys and similar cylindrical parts. NSF/ANSI 61 Certified. ABS Approved.