Hardinge Mill Rebuild

I hand scraped the table, universal saddle and the knee of my mill, but the column evidently needs it too. When I moved the
table up and down it loses alignment with
the cutter, which is not a good thing considering that I have the Hardinge vertical head.

My local grinder wants $800 to grind the column, which seems high considering that
I can get a Monarch lathe bed ground for about half that. Especially since the Hardinge is just a simple dovetail. What am I overlooking?

-Dave

Hi rimcanyon:
I will give your way grinding question a shot.First, the bed of a Hardinge toolroom lathe,which I believe you refer to as costing half as much to grind as the vertical ways of the milling machine is a removable hardened plate. This plate can be mounted on a mag-
netic chuck and ground with all functional surfaces within the bed itself. All this is pretty straightforward grinding.

The column of the miller on the other hand requires very, very careful alignment of the spindle(read that bearing)bores in order to maintain squarenessin two planes; one, the vertical, to assure that circular cutters don't cut out of square to the table surface,two the horizontal, so the cutter doesn't "crab" through it's cut and produce a slot wider than the cutters width.

A good share of the additional cost will go into the setup for the mill, since the column doesn't have too many convenient clamping surfaces.

Since this my first attempt at posting ANY
MESSAGE on a BB I hope this makes sense.
Good luck with your project.

See!! My first post and I blew it! My story remains the same,though.Since there is no outside feature to align with, the bed will be easier to grind. In fact, due to the extreme stiffness of the Monarch bed, it being a very robust casting, it could be easier to grind than the Hardinge bed.

[This message has been edited by EAH (edited 10-14-2002).]

EAH, thanks for the reply. I think your analysis is right on. Setup is the issue.

If I was going to setup the mill for grinding I would use the overarm bar as one frame of reference, and the ways as the other. i.e., clamp the overarm bar into its bore and set the mill up so that the overarm was perpendicular to the grinding table (it could even be used as a support for the ungainly casting on the back side of the column). Then set the ways parallel to the grinding table.

You're right, that is a lot more work than just setting the EE bed on the grinder, making it parallel to the bed.

rimcanyon: I suspect you had the answer all the time. All it took was a little prompting to bring the solution to the fore.

All the best, EAH