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Jim Hubbell
03-06-2008, 07:57 PM
I have been using my HF tool grinder for a while and was not happy with the wheels supplied. With the help of this board I was pointed toward a few suppliers. I ordered a wheel by Norton and from a different provider a wheel from Israel. Both AlOx. There is a wide disparity in cost but the two wheels came to ten dollars less than the machine. The spindle hub and the less expensive wheel were adapted so as mount properly. A small amount of run-out appeared visually. Brought up to speed and the face trued it does a nice job of grinding. After fitting the Norton wheel to the other hub and giving it a spin by hand I was taken aback by the run-out observed. After a few spins by hand it seemed the balance was not far off. Standing back I applied power and it came up to speed. While the circumference galloped the working face ran very true. Though the balance seems fair I wonder what the run-out is doing to the wheels. Run-out (radial) better than 0.050”. The next step is an adapter so as to balance each wheel individually.
Mainly I was surprised that the expensive wheel was so far off and wonder if this has been noticed by any of you.
Thank you for any comments and/or suggestions.

Bruce Griffing
03-06-2008, 08:04 PM
Do you have a diamond truing tool? If so, you can simply round the wheel in situ.

Jim Hubbell
03-12-2008, 12:48 AM
After I respectfully buried the suggestion of carving off the O.D. of the grinding wheels, I built an adapter hub so as to properly balance them. I am happy to say they are very smooth. The only vibration coming from the motor rotor. I do not plan on pulling the machine down for that.
I did post a few pictures on my site.

http://picasaweb.google.com/shopm8

Look in mach.

wirewrkr
03-12-2008, 01:31 AM
I've been reading with interest for some time now about the infamous tool bit grinder from HFS. It seems that about 50% of the buyers that have posted or replied to threads here are having to modify, replace wheels repair, fine tune etc...
Has anyone tried the same tool from Grizzly that is $169.00?
Are you experiencing the same problems as frequently?
I imagine that Grizzly would be better at standing behind their product than HFS.
I've had bad luck getting a problem fixed from HFS in the past and finally gave up and scrounged all the missing hardware from the press I bought from them last year.
I am ready to spring for one of these grinders but would like to here if anyone has bought the Grizzly version (it looks identical to HFS) and what kind of results or opinions you have or had.
Robert

Your Old Dog
03-12-2008, 08:20 AM
I imagine that Grizzly would be better at standing behind their product than HFS.


I have never had HF question any of my returns. The stuff is cheap enough I find myself looking at them as kits as others have mentioned here on the forum. I got lucky I guess because mine works fine right out of the box.

Bill Pace
03-12-2008, 08:53 AM
I dont recall any particular comments about the Griz/HF, but Grizz has its share of problems with shoddy stuff, and you may find a similar set of gripes with it after youve paid the extra/w shipping, which will mean shipping back, -- etc. (this thing is HEAVY!!)

Like Dog says, HF has very laid back approach to returns --- I read of one guy took 3 of them back and finally got one he accepted! and no hassling with shipping.

Just get it expecting to have to "tune it up" --- replace the wheels, do a bit of tweaking on the tilt tables, probably replace the cheesy socket head screws, etc --- an hour or so in the shop will probably bring it around to be one NICE addition to the shop.

texas_po_boy
03-12-2008, 09:13 AM
[QUOTE=Jim Hubbell]After I respectfully buried the suggestion of carving off the O.D. of the grinding wheels, I built an adapter hub so as to properly balance the wheel.




Hey Jim that is a neat looking table and arm assembly you got there. Got any drawings you could post? The table at the other end also.

bighammer
03-12-2008, 10:07 AM
nice table worth much more than the grinder..

BobWarfield
03-12-2008, 11:24 AM
I have a hard time seeing wheel replacement as a major "fix". It's an upgrade. The wheels that came with mine work, they're just not as nice as a set of "pro" wheels.

bighammer and texas_po_boy, I'll be interested to hear from Jim, but the far table looks to me like it is just the stock table. The near table looks like one of the XY tables you can buy in so many places with an interesting x-axis "feed" modification. It's nice to have one with the grinder. The lower position makes room for more complicated assemblies to be mounted on top.

Things like this:

http://www.cnccookbook.com/img/Tooling/P1010214.JPG

Those tables are not very expensive if you wanted to add one.

I do like your little lathe tool holder Jim.

Cheers,

BW

Carld
03-12-2008, 11:47 AM
:eek: wow Jim, nice looking attachment. I think that's over kill just to sharpen cutters though. Real nice job though.

The accepted way to take the odd shape or wobble out of the wheel is to dress the sides and face to make it run true.

It has been mentioned that the Chinese and others may be making wheels for Norton.

From what I have read the HF, Grizzley and other look alike cheap tool grinders are made by the same company in China. If true then all would have the same defects. I have a HF tool grinder and after some fitting up of parts have found it to be a very good grinder.

I have used the small adjustable guide to grind cutters with but mostly do them free hand on the table.

miker
03-12-2008, 05:29 PM
:

It has been mentioned that the Chinese and others may be making wheels for Norton.

http://img.photobucket.com/albums/v448/mikerr/PB240003.jpg

New Norton wheels I bought for my grinder. Made in China.
Seem ok though. Just dressed with Diamond then Dressing Stick. No vibration.

Rgds

Jim Hubbell
03-12-2008, 09:34 PM
First off, the X-Y table is a cheap Chi/enco unit with the X motion imparted through a piece of roller chain and sprocket. ( to lazy to build a rack gear )

The "pylon " mount assy. is an ongoing project. As needed, various adapters may be added. I hope to set it up for drill bits. The 1/4 in. sq. tool holder is set to make 60 deg. points for cutting threads. Those were hard to grind "offhand " and not have a valley of a cut. Nasty looking threads. The first threads I have cut using a bit ground on this set-up were 14tpi for the hub adapter shown. Turned out nice looking though they don’t show well in the picture.

No prints on this stuff as all the napkins got thrown out.

The Norton wheel shown does say USA. Since balancing it is very smooth running but of course still has radial run-out. The working face was true from the start.

Thank you all for the come-backs.