MadModder

The Shop => Tools => Topic started by: Bolster on November 19, 2010, 02:17:26 PM

Title: Does Cup Grind Wheel in Mill Spindle = Poor Man's Surface Grinder?
Post by: Bolster on November 19, 2010, 02:17:26 PM

Is that possible? Or is it crazy? Putting a cup-style grinding wheel in a vertical mill's quill and using it as a surface grinder? Obviously you'd have to shield/protect the ways....Anybody tried this?

Title: Re: Does Cup Grind Wheel in Mill Spindle = Poor Man's Surface Grinder?
Post by: Bogstandard on November 19, 2010, 03:07:21 PM

If your mill can get up to over 5000rpm, then yes.

Bogs

Title: Re: Does Cup Grind Wheel in Mill Spindle = Poor Man's Surface Grinder?
Post by: Trion on November 19, 2010, 04:15:36 PM

I know nothing about surface grinders, but logic makes me think  the spindle speed needed depends on the wheel size!? :scratch:

Title: Re: Does Cup Grind Wheel in Mill Spindle = Poor Man's Surface Grinder?
Post by: Bolster on November 19, 2010, 07:20:12 PM

Quote from: bogstandard on November 19, 2010, 03:07:21 PM

If your mill can get up to over 5000rpm, then yes.

Bogs

Then I am screwed. 2000 is my top speed. Darn it.

Title: Re: Does Cup Grind Wheel in Mill Spindle = Poor Man's Surface Grinder?
Post by: Andrew_D on November 19, 2010, 08:01:24 PM

Quote from: Bolster on November 19, 2010, 07:20:12 PM

Quote from: bogstandard on November 19, 2010, 03:07:21 PM

If your mill can get up to over 5000rpm, then yes.

Bogs

Then I am screwed. 2000 is my top speed. Darn it.

As mentioned, wheel size plays a role....just get a larger wheel to keep the feet per minute of the cutting edge up high enough.

Andrew

Title: Re: Does Cup Grind Wheel in Mill Spindle = Poor Man's Surface Grinder?
Post by: Bogstandard on November 20, 2010, 12:14:47 AM

I use up to 8" wheels on my surface grinder, and they are rated up towards 6K RPM.

I have used a large diamond lap at fairly low speeds under experimental circumstances, but that would require flood coolant and is limited to the materials you can use it on.

http://madmodder.net/index.php?topic=2232.0

I am also playing about with diamond coated laps, but that is a little in the future.

http://richontools.com/index.php?main_page=index&cPath=1_9

and their associated backing plates

http://richontools.com/index.php?main_page=product_info&cPath=45&products_id=797


Bogs

Title: Re: Does Cup Grind Wheel in Mill Spindle = Poor Man's Surface Grinder?
Post by: Lew_Merrick_PE on November 20, 2010, 11:14:19 AM

The basics of a surface grinder are not all that complicated.  The "issue" is defining a set of specifications that would make for a good overall project.  The size of the unit is fairly easily varied, but I would need good definition as to the resolution of (downfeed, mostly) such a unit.  Laying out such a design is fairly trivial once the specifications are set.

How about: 6 inches (150 mm) vertical feed with .0005 inch (0.01 mm) nominal vertical feed resolution; 18 inches (450 mm) longitudinal table travel X 8 inches (200 mm) crossfeed table travel; with a ø1.250 inch (ø31.75 mm) wheel spindle as a baseline?  Personally, I prefer a pneumatic longitudinal drive, but a cable-type drive is doable.  What criteria would be appealing here?

Irrational minds want to know...  ;-)