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paulsv
05-10-2010, 02:25 PM
I recently bought this tool grinder from HF:

http://www.harborfreight.com/1-2-half-hp-6-inch-tool-grinder-46727.html

I have a couple of newbie type questions:

1. It came with two green wheels, which have a metal plate on the back side, and then a ring-shaped grinding stone attached to the metal backing. They do a pretty good job of sharpening brazed carbide bits, but they are slow on HSS, and heat up the bits pretty quickly. Also, one of them seems to be out of balance. I'd like to try an aluminum oxide wheel. I checked Enco, but couldn't find that style of wheel. Can anyone tell me what that kind of wheel is called, and where I can get such wheels? What is the best way of trueing the green wheels?

2. The table tilt mechanism is poor- it is hard to move the tables, becasue they bind. I have played around with the alignment of the parts, and gotten a little improvement. Does anyone else have this grinder, and do you have any tips on getting the table tilt mechanisms to work smoothly?

MTNGUN
05-10-2010, 02:54 PM
Lots of old threads on this grinder. Your observations on the grinder are about the same as mine and others.

I bought an Al-Ox wheel from KBC, *might* have been #1-704-368, but it's been several years, so don't take my word for it.

Most people eventually dump the green wheels. My grinder is now set up with a diamond wheel on one side and the Al-Ox wheel on the other. Works very well.

You may have to grind the guards to provide clearance for the new wheels.

lynnl
05-10-2010, 03:32 PM
That's quite a price increase.
Just a couple of years ago that grinder was almost always advertised on sale at $119.

Can it be easily modified to take a standard bench grinder wheel? I've never looked closely at shaft.

Jim2
05-10-2010, 04:14 PM
Here's what you want

http://www.wttool.com/category-exec/category_id/13473

Jim

paulsv
05-10-2010, 04:16 PM
That's quite a price increase.
Just a couple of years ago that grinder was almost always advertised on sale at $119.

Can it be easily modified to take a standard bench grinder wheel? I've never looked closely at shaft.

I believe it sells in the stores (or did when I bought mine a few months ago) for $159. and then with the 20% off coupon, it was $127, so the effective price isn't much higher. The $159 is sometimes discounted to a sale price as well. Seems like a lot of machine for that price to me.

I haven't considered whether it would take standard bench grinder wheels, because in order to use the table tilt to set angles, you have to grind on the side of the wheel.

loose nut
05-10-2010, 04:19 PM
Here's what you want

http://www.wttool.com/category-exec/category_id/13473

Jim

I also put these, from Wholesale Tool, on mine and they work great. HSS cuts like butter.

paulsv
05-10-2010, 04:47 PM
I also put these, from Wholesale Tool, on mine and they work great. HSS cuts like butter.

Thanks, guys, jhust what I was looking for.

reggie_obe
05-11-2010, 11:29 AM
Lots of old threads on improving this grinder and making accessories for it. Yes, the original wheels are crap and out of balance even after dressing the face, toss them. For the money the KBC A/O wheel is great. The table tilt is stiff at best, I still haven't gotten my to work smoothly yet. Paid $109 a while back. I wish I had waited and just bought a Baldor, Prosser or similar grinder at auction.

paulsv
05-11-2010, 01:40 PM
Lots of old threads on improving this grinder and making accessories for it. Yes, the original wheels are crap and out of balance even after dressing the face, toss them. For the money the KBC A/O wheel is great. The table tilt is stiff at best, I still haven't gotten my to work smoothly yet. Paid $109 a while back. I wish I had waited and just bought a Baldor, Prosser or similar grinder at auction.


Yes, I originally did a search on "HF Grinder" and found nothing. Then after I posted my question, I did a search on "Harbor Freight Grinder," and found the old threads. Lots of good info there. I'm ordering the KBC A/O wheel. Haven't decided yet on whether to get a green silicon carbide wheel or spring for a diamond wheel for grinding carbides. If I make any progress on the tables, I'll report.

chuckinnc
05-11-2010, 02:02 PM
The grinder is great but the table are terrible, mine binds tight all the time. I
bought mine in Janurary of this year, it had out of square aluminum trunions (slides) I had to mill the insides flat so they would be the same all over
that helped but are still a pain to adjust.

Carld
05-11-2010, 11:33 PM
Forget buying a green wheel and buy a diamond wheel for carbide and an Aluminum Oxide wheel for HSS. You can get a diamond wheel from CDCO at a reasonable price.

dp
05-11-2010, 11:42 PM
The grinder is great but the table are terrible, mine binds tight all the time. I
bought mine in Janurary of this year, it had out of square aluminum trunions (slides) I had to mill the insides flat so they would be the same all over
that helped but are still a pain to adjust.

I did exactly the same with my tables and they still bind. I think its the aluminum galling against the steel glides.

lazlo
05-11-2010, 11:50 PM
Forget buying a green wheel and buy a diamond wheel for carbide and an Aluminum Oxide wheel for HSS. You can get a diamond wheel from CDCO at a reasonable price.

I tried mounting a 3M diamond wheel, but mine has *way* too much runout. You can dress it out on a thick AO wheel, but you don't have have option on a diamond wheel.

Black_Moons
05-12-2010, 12:04 AM
You adjust the runout by the 4 beveled mounting screws, use a felt pen or something to mark the area of high runout and loosen the opposite screw and tighten the screw thats 'high'

At least, thats the only reason I can come up with for them using those silly screws.

lazlo
05-12-2010, 09:38 AM
Those 4 aluminum screws are for the plate mounted Type 10 AO (or Silicon Carbide) grinding wheels. Diamond wheels have counter-sunk mounting holes and use a 5/16" flat-head screw.

But my point is the run-out on these Harbor Freight grinders precludes the use of diamond wheels. Forrest shimmed his, which is a lot of work. Eventually I'm going to tear mine down and turn the shaft, spigot, and mounting plates true.

gzig5
05-12-2010, 10:29 AM
Those 4 aluminum screws are for the plate mounted Type 10 AO (or Silicon Carbide) grinding wheels. Diamond wheels have counter-sunk mounting holes and use a 5/16" flat-head screw.

But my point is the run-out on these Harbor Freight grinders precludes the use of diamond wheels. Forrest shimmed his, which is a lot of work. Eventually I'm going to tear mine down and turn the shaft, spigot, and mounting plates true.

On mine, the shafts ran true and smoothly with the wheels off, but the aluminum wheel mounts were left basically as cast and of course the wheels are crap. To quickly get it into service because I didn't have large enough material to make from scratch, I bushed the hole in the wheel hubs and then mounted on a shaft in the lathe and squared both ends. I then used a diamond to true up the original wheels and the thing runs smoothly and true. Need to get an AO and diamond wheel, fix the table adjustment and make new wheel hubs from steel when the time becomes available. These grinders start out as sow's ears but can be made to make a decent purse.

Dave S.
05-14-2010, 08:02 PM
Well I just got a new diamond wheel from Enco on there 15% off sale. Nice looking wheel. Went to put it on the HF grinder. As others have discovered the adapter plate had about 1/32 wobble. Ok we can make up an arbor and correct that. Not when I get it off the shaft there is a big chip out of the back side. Next problem the holes in the new diamond wheel are smaller than the bolts that need to go through them. Next check to see if the wheel will go on the adapter. Not the bore in the wheel is smaller than the adapter plate. Up shot is the grinder is sitting in the shop in pieces and I am going to have to make a complete new adapter plate. Doable.
The folks in China put a roll pin into a blind hole as a key for the adapter and it looks kinda smashed. So now I will need to figure out how to get that out and replace with a custom made pin.

Darn good thing I had a 20% off coupon when I bought the grinder.

Dave

BadDog
05-14-2010, 10:40 PM
I'm sure glad I waited and got a real Baldor. Good luck with getting it sorted out...

Doc Nickel
05-14-2010, 11:52 PM
I'm sure glad I waited and got a real Baldor.

-Ditto. I almost grabbed one of the imports a couple of times, but shipping was always the deal-breaker.

I finally found a Baldor that had been well-used and partly "rebuilt". Despite being kind of rough externally, it still runs quiet and smooth. Wasn't a screaming deal at $300 at auction, but considering the shipping on the HF unit alone would have been some $80, and all I had to do to this one was slap a new name-brand green wheel on it, it was worth it.

I'm 'bout done buying imports, unless I absolutely have to.

Doc.

smiller6912
05-15-2010, 12:15 AM
The folks in China put a roll pin into a blind hole as a key for the adapter and it looks kinda smashed. So now I will need to figure out how to get that out and replace with a custom made pin.


Dave

Use a tap (or "E-Z out) to dig into it and lever it out with some pliers,
(CAUTION: It will take several attempts, and may permanently damage the tool)
I do it all the time.........
Just replace it with another roll pin , now that you can get it out..........

lazlo
05-15-2010, 09:54 AM
I'm sure glad I waited and got a real Baldor. Good luck with getting it sorted out...

You suck Russ :p

I've been looking for a Baldor carbide grinder in Central Texas for years. People don't want to give them up...

Dave S.
05-15-2010, 12:38 PM
I expect that that roll pin being made in China is not as hard as one made here. I'll need to see if I have a tap that will fit that I don't care if it gets distroyed in the process. My other thought was to melt some machineable wax into it, after a made a punch that just fits the ID. then take the punch and tap it in and have hydraulic force push the roll pin out.

Dave

BadDog
05-15-2010, 05:04 PM
You suck Russ :p
Oh, you have NO idea... :cool: But let me tell you the rest.

Mine was bought new, used in a home shop for a few years, and then came to me in very good shape and low use... with 2 good quality diamond wheels, one fine and one medium, both in good shape. Just so you know, it cost me $300, and he delivered it.

That's just payback for some of the deals I know you've gotten (and others here) that make me green with envy. Payback and all that. :p

Jim Hubbell
05-15-2010, 11:17 PM
As I started assembling my HF grinder I decided it must be an unfinished kit. Took it apart and figgured how each piece should fit and work. After remachineing and assembling the tilt tables, I simply loosen the clamp screws slightly, to easily tilt the table. The AO wheels I purchased for it were quite a bit out so they were balanced using lead weights and epoxy. They were balanced on a seperate balancing shaft.
The machine is now usable but not perfect. I feel it was worth the $140 including shipping.

knudsen
05-16-2010, 01:18 AM
Jim (and others), now that you have it working, if you had it to do over, would you buy another or make one from scratch or from an old pedestal/bench grinder? That's assuming a Baldor is not an option.

I've almost bought one about ten times. I know it needs rebuild and reworked and maybe redesigned. Each time, I thought I could use the money for decent wheels and roll my own. Now that I know about the $30 WT wheels, it's more tempting to get one.:confused: :confused: :confused:

Jim Hubbell
05-17-2010, 12:55 AM
Knudsen-
To answer your question--Yes. I realize it is not a Baldor but it does all my home shop asks of it.
The fact that it was unusable as received did not deter me as I enjoy rebuilding and seeing it work well in the end.

Cheers

dp
05-17-2010, 12:58 AM
I bought the HF grinder and except that it needed a lot of TLC, it's been a fine grinder, so far. I need to take another go at clearing up the binding tables problem, though.

lazlo
05-17-2010, 12:21 PM
Agreed, it's a good deal if you're just planning to use it with AO wheels (chuck the crappy green wheels). But diamond wheels are a challenge, because of the runout...