Harbor Freight Central Machinery 8" Bench Grinder Item No. 39798

My son was in the market for a bench grinder recently, and I advised him against getting a 6" machine. While 6" bench grinders are widely available and not too expensive, I consider them to be borderline toys. The 'hollow grind' effect of an 8" grinder is not so severe, and the linear speed at an 8" wheel's periphery is higher.

My son wasn't too keen on the cost of an 8" bench grinder, but on a recent visit to the USA he happened to pick up one of these from Harbor Freight.

With a coupon, he got it for $39.00 US -- an incredibly low price for an 8" grinder.

Needless to say, though, for a price like that one is not getting a high-end piece of fine machinery. The axial run-out (wobble) of the left side wheel is awful, and the machine runs with a nasty vibration. Just out of curiosity, I'm going to measure axial and radial run-out on both wheels. Then I'll see what, if anything, I can do to correct it.

Axial Run-Out Measurement

Here's my setup for measuring axial run-out at a wheel's periphery.

Axial run-out on that wheel is about 0.060"!

Radial Run-Out Measurement

And here's my setup for measuring radial run-out at the edge of a wheel

Radial run-out on that wheel is about 0.020".

Contributors To Axial Run-Out

First off, for some odd reason, the left side wheel didn't have full labels on its faces -- only the remnants of labels.

I scraped and wire brushed the label fragments to get a reasonably uniform wheel thickness where the flange washers contact the wheel.

The inboard flange washer had axial run-out built into it.

About 0.015". I turned the face of the flange washer to get rid of that.

And finally, the spindle that the inboard flange washer goes on had very little in the way of a shoulder for the flange washer to butt up against, making for an uncertain fit of the inboard flange washer on its spindle.

There's only 0.5mm of a shoulder.


I ended up doing a trial-and-error fit of the whole spindle/flange washers/wheel assembly, experimenting with differing angular relationships of the parts until I got lucky and found the sweet spot where axial run-out was all but gone. I did the same on the right side wheel as well, to good effect.

I dressed the wheels' edges with a diamond dresser; that got the radial run-out to under 0.010"

And that did it. The grinder now runs much, much better.

In Conclusion

For $39.00 US you can get a functioning 8" grinder, but be prepared to put some work into it to get it to run nicely.

The lack of robust spindle shoulders for the inboard flange washers to butt up against is poor design -- one wonders what the manufacturer has for engineering 'talent'.

The toolrests are a bit flimsy, and lack any angular or height adjustability; they're only adjustable for distance from the wheel.

The 3/4 hp rating of the motor looks optimistic to me. (Note that the I.D. label doesn't give an amperage figure.) My hunch is that it's closer to 1/2 hp, but it's quite adequate whatever it is.

For what it's worth, the 3,450 rpm figure is full load speed. No load speed is 3,568 rpm, as measured with a digital photo tachometer.

Not that it's a problem, but just so you know, there's no braking feature. It takes over 3 1/2 minutes for the wheels to coast to a stop after the machine is switched off.

And there we are. As with most of home workshop machinery, 'you pays yer money and you takes yer chances'.

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2009 Hyundai Tucson Windshield Wiper Replacement

Introduction

I bought my Tucson used, so I don't know whether the wipers on it were original or not. In any event, the old wipers I replaced are Bosch. They have a black plastic cover over the attachment point with "BOSCH" embossed on it, like so.

Replacement Wipers

I got low-end replacements from rockauto.com, ANCO P/Ns ANC 14C-16 and ANC 14C-24. Better wipers can be had for more money, but the pictured ones are adequate.

Wiper Replacement

Each wiper arm terminates in a 'J' hook that has to be slid off its mating pivot on the wiper blade. To remove a Bosch blade, first pry off the black plastic cover from underneath with your thumbnails. Get the cover moved over out of the way of the pivot.

Now, if you forcefully shove the wiper blade in the direction of the wiper arm, you'll free the blade from its 'J' hook.

Installing A New Blade

Slip the wiper arm's 'J' hook into position over the new blade's pivot point, and forcefully tug on the blade to get it to snap into place. When you're properly done, the 'J' hook/blade interface should look like this.

And here's a view of the new 16" wiper installed.

And both wipers replaced.

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2009 Hyundai Tucson Rear Glass Gas Spring Replacement

Replacement Gas Springs

I got mine from rockauto.com -- SACHS P/N SG367011. Here's a view of them as received.

The label on the sleeve identifies them as "STABILUS LIFT-O-MAT". English installations are printed on the back of the sleeve. A paper insert has French and Spanish instructions.

Propping Up The Rear Glass

If you happen to have a helper, then he or she can hold the glass up for you while you swap the gas springs. That's what the instructions advise. The instructions go on to say, "DO NOT USE ANY KIND OF PROP TO HOLD UP HOOD/TRUNK/HATCH."

I had no helper, so I ignored that warning and propped up the glass with a board approximately 74 inches long, like so.

That worked fine for me. I don't see a problem with doing it.

Removing A Gas Spring

A steel clip secures each ball-end to its ball stud.

Pry each clip part way off with a screwdriver (there's no need to remove a clip completely), and the ball-end will be free to come away from its ball stud.

Installing A New Gas Spring

Position each ball-end over its corresponding ball stud and press forcefully. The ball-end will snap into place on its stud.

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