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View Full Version : Enco vs Harbor Freight carbide grinder



noah katz
12-03-2010, 01:44 PM
The Enco is on sale, though still about $50 more.

Is it better quality?

This assumes I'd check the HF in the store for runout.

lazlo
12-03-2010, 01:51 PM
I would imagine they're exactly the same machine, minus the grey versus green paint.

Most seem to need some tweaking to minimize the runout. Taking the cast aluminum wheel mounts and the shaft spud behind it off and turning them true helps a lot.
If you're using a thick Type 35 plate-mounted wheel, you can dress-out most of the runout anyway.

The problem I've had is trying to run a diamond wheel on mine.

gwilson
12-03-2010, 02:36 PM
I bought a HF for the shop I worked in. I liked it because it was REVERSIBLE,and for a long time it was THE ONLY reversible one out there except the Baldor. I think Enco finally started carrying a reversible one. I'd go for the HF. They are the same.

mc_n_g
12-03-2010, 02:47 PM
I second the info about removing the spindle and aluminum mounts and turning them true.
Defintely removes vibration. Immediately toss the green rocks you get with the grinder. Get auminum oxide wheels or cbn wheels

mechanicalmagic
12-03-2010, 03:02 PM
I have both. The ENCO was NOT reversable, and the catalog still shows a simple ON-OFF switch, so I assume they have not changed it.

I would gladly swap the ENCO for a HF any time. Reversable rotation means you can use different wheels. Without reversing, you need to buy two identical wheels so you can grind all sides of a tool.

The supplied green wheels are junk.

noah katz
12-03-2010, 04:18 PM
Thanks for the all good info, will get the HF and true it up.


I would gladly swap the ENCO for a HF any time. Reversable rotation means you can use different wheels. Without reversing, you need to buy two identical wheels so you can grind all sides of a tool.


Why's that - isn't all grinding done on the front face?

EddyCurr
12-03-2010, 04:34 PM
Taking the cast aluminum wheel mounts and the shaft spud
behind it off and turning them true helps a lot.Have you successfully removed the aluminum flanges from the shafts
of a Harbor Freight #46727 6" Tool Grinder (http://www.harborfreight.com/1-2-half-hp-6-inch-tool-grinder-46727.html)?


http://www.harborfreight.com/media/catalog/product/cache/1/image/370x/9df78eab33525d08d6e5fb8d27136e95/i/m/image_1263.jpg

gwilson had posted about the runout these machines are prone to
exhibit and described a method for improving the condition in post #26
below which I adopted for truing the flanges on my machine.


HF 6" Tool Grinder - Owner Satisfaction ? (http://bbs.homeshopmachinist.net/showthread.php?t=39410&page=3)

The end result wasn't as nice as if the flange had been trued in a lathe,
but it was adequate.

.

914Wilhelm
12-03-2010, 05:22 PM
Can anyone post a recommendation for an Enco part# for a good wheel for grinding carbide for this machine?

mechanicalmagic
12-03-2010, 06:46 PM
Why's that - isn't all grinding done on the front face?

With a single direction machine, YES. However, there are times when grinding on the back face is VERY handy. Like the right side of an o-ring tool.

If you are grinding Carbide, and using Diamond wheels, you need two wheels. (Or time to move the wheel to the other side.) Significant extra expense.

noah katz
12-03-2010, 07:35 PM
With a single direction machine, YES. However, there are times when grinding on the back face is VERY handy.

Still not getting it - the back face of the wheel is a metal plate, no?

Or do you mean using the O.D. of the wheel, in which case I get it.

Carld
12-03-2010, 11:01 PM
Noah, what they mean is because of the surface of the cutter your grinding on you have to use the right or left side of the table on the wheel. If your grinding the left side of a cutter you have to reverse the wheel and use the left side of the table then the wheel is rotating down.

when you grind the right side of a cutter you use forward and the right side of the table.

noah katz
12-03-2010, 11:29 PM
If your grinding the left side of a cutter you have to reverse the wheel and use the left side of the table then the wheel is rotating down.

Why can't the left side of the cutter be sharpened on the right side of the table?

Carld
12-03-2010, 11:50 PM
We are talking about a tool grinder now like the Baldor or HF tool grinder. Stand facing the flat side of the wheel with the table in front of you. Take the cutter and lay it on the right side of the table with the side of the cutter against the wheel, not running of course. Which side of the cutter is against the wheel.

The right side of the cutter will be against the wheel and if you try to turn the cutter around to cut the left side your fingers will be in the center of the grinding wheel with the big nut and screws that hold the wheel on the motor shaft. You won't like to be there when the motor is running.

To grind the left side of the cutter you reverse motor and move the cutter to the left side of the table and put the left side of the cutter against the wheel.

You can grind the front of a cutter on either the left or right side of the wheel.

Forrest Addy
12-03-2010, 11:58 PM
There's another thing to consider about anything that involves a cheap Asian built motor. First, there'd nothing basically wrong with Asain motors but if the final dip and bake is omitted the windings are not bonded together. They can shift and buzz together chafing the insulation leading to short circuits and smoke. And they do smoke early and for no apparant reason and the reason is the buzzing and chafing and the short circuit alluded to.

A sensible purchaser goes through an import product as decribed above checking, fettling, and fine tuning whatever is found to be dubious. Testing the bond of the stator windings is a simple matter of cratching at them with a thumbnail. If they can be separated they are not bonded. Take the stripped stator to the local motor shop late in the week and ask them to dip it over the weekend and bake it. If you wih to make the motor reversible, ask the motor shop to trace out the leads. Incidentally have them separate the start and the run windings so they can be reversed bringing out the extra lead. Install a reversing switch at this point if you need it. This is a double pole double throw switch to be wired in the usual way. You still need the on-off switch. Note, this kind of motor will not instant reverse.

The final thing: some if these import grinders have no centrifugal start witch. Instead they have a potential sensing start relay tucked in the base. It MAY have a gravity solonoid core. Accidentally reinstalling it upside down means the start switch will not work. Reinstall it right side up. DAMHIKT

gwilson
12-04-2010, 12:02 AM
You MUST have reverse if you are grinding tools. I AM PRETTY SURE Enco now offers a reversible one.

Truing up the wheels like I have suggested,right in situ does make them perfectly true,possibly truer than if you take them off and do it in a lathe. Truing in place always makes a better truing up. Hardinge HLVH lathes have their spindles ground after the lathe is assembled.

I used the HF grinder for maybe 4 years without it going bad. But,I did not use it every day by any means. I have a reversible Bridgewood at home,but they aren't offered anymore. Still from Taiwan. I'd just get the HF,and read the reference last page where I described truing the wheels up. The wheels aren't out MUCH from the factory,but if you are using plated diamond wheels,you need it to be DEAD true,or you will wear out just 1 area on the wheel.

SOME plated wheels have a thin rubber backing,which you can make to run true by selectively tightening the bolts that secure them against the aluminum plates.

gwilson
12-04-2010, 12:04 AM
Forrest,your info is valuable,but you are making a lot of typos.

Dave S.
12-04-2010, 12:28 AM
I bought one from HF. When I got it home and checked it the adapter plates that the grinding wheels bolted up to had so much wobble you could not keep a tool from bouncing. Pulled the adapters and found that the person that had assembled did not bother to clean the paint off the motor shafts that they did not mask off before painting the unit. The spacer that the adapter seated against was trapped behind a roll pin in a blind hole they used for a key. Got one out by filling it with wax and driving a pin punch down the inside of the roll pin and using hydraulic pressure to push it out the other side I had to use a diamond bur in the dremal to get it out.
Then I wanted to mount a diamond wheel on one end and the existing adapter plate did not have the correct bolt hole pitch diameter. So made a new adapter for that.
Tables would not tilt without great difficulty so had to redo them.

After much tweeking it is doing a good job.

The reverse switch did work from the get go.:)


Dave

gwilson
12-04-2010, 09:37 AM
I NEVER had that kind of trouble,Dave!! Maybe I'm just lucky. My plates wobbled a teeny bit,easily cured by clamping a carbide tool to the miter gauges,and carefully passing it across the face of each flange. No problem with the flange holes.

noah katz
12-04-2010, 04:16 PM
The right side of the cutter will be against the wheel and if you try to turn the cutter around to cut the left side your fingers will be in the center of the grinding wheel with the big nut and screws that hold the wheel on the motor shaft. You won't like to be there when the motor is running.

I see, thanks much, Carl.


The spacer that the adapter seated against was trapped behind a roll pin in a blind hole they used for a key. Got one out by filling it with wax and driving a pin punch down the inside of the roll pin and using hydraulic pressure to push it out

Slick!

AllThumbz
12-04-2010, 05:35 PM
You guys are making me glad I bought a used Baldor on Fleabay. There is just too much work to do on the HF/Enco models....

Brett Hurt
12-04-2010, 06:04 PM
I like it but the tool grinding adjustment is hard to do not smooth, but other than that it is fine