Dressing a grinding wheel?

[chopnhack]

I have read some reviews on the Harbor Freight 8" grinder that say the grinder is ok, but the wheels are out of balance and cause much vibration, simply to buy better wheels.
Can you rebalance these wheels using a diamond dressing wheel? In other words, does dressing the wheel rebalance it or are you simply squaring the surface?

[dbhost]

Not sure about the consistency of the density of the HF wheels, but I KNOW from first hand experience that Norton white wheels are simply NOT true. In order to get mine concentric with the shaft on my Ryobi 8" grinder I had to...

#1. Chuck the stupid plastic inserts, and order one piece stainless steel inserts from McMaster Carr.
#2. Order and use a Geiger's Dressing and Truing solution tool. This is NOT a cheap tool, but I have several grinders to deal with. (Ryobi 6" that I use for lawn tools and such, Ryobi 8" that is my sharpening station, and several grinders for friends and family... ) I was VERY leery of paying out the bucks Don Geiger wants for his fancy pants little gizmo, but it really did the trick. If you were in the Houston area, I would say drop by with the grinder, and we will try my Geiger's tool on it...

Long story short, it is a rare find for aftermarket wheels to fit 100% correctly, and be completely concentric when they come out of the packaging... Dressing a wheel only does part of the job, truing it means you made it square, AND concentric...

And before anyone fusses, I picked the Ryobi 8" grinder SPECIFICALLY for its RPM rating. I went with what OneWay recommends with their Wolverine jig, as well as various members of the turning clubs near me... I know a LOT of guys prefer the slow speed grinder, and more power to ya... But the folks that I figure should know best were all telling me the 3650 rpm grinders are the way to go... Been up this way for about 6 months trouble free, and I have touched up my turning tools a LOT since I put it all together...

[drillman88]

I would think if the wheel was really close to being centered with the shaft and the balance was fairly close you could probably true the wheel to the shaft and get it usable. If the balance is way off or your wheel is not centered to your shaft you might not be able to get it to work. If is too far off center you could remove material from the wrong side and actually make the balance worse. If they are cheap enough you can try a few and see if it would work.

[chopnhack]

Wow, didn't know that it could be that involved. Thanks for the invite, dbhost. I currently don't have a grinder and was just getting more info before buying one.

[dbhost]

Wow, didn't know that it could be that involved. Thanks for the invite, dbhost. I currently don't have a grinder and was just getting more info before buying one.

Not sure about the HF, but the Ryobi I have, the BGH-827 had pretty good, wheels for OE gray wheels, but I wanted the cooler grinding white oxide wheels. Once I pulled the OEM wheels off, I noticed that the Nortons I put on were BADLY out of true, and made the grinder vibrate so bad that it would make the whole workbench jump... I looked into it, and found a lot of discussion on SMC about this issue. It's not the cheapo grinder, it's the poor bushings and machining on the wheels that is to blame... Like I said, with the proper bushings, and a good truing on my wheels, the grinder purrs like a kitten now...

Yeah, grinders can be complex if you want them to be smooth... It's all in the balancing act. Think of it this way, how is a tire going to behave on the road if it is badly out of round spinning at 3650 rpm?

[chopnhack]

Very true, Db, very true It makes me wonder if alot of the complaints and poor feedback received over grinders is nothing more than poor fitting wheels or out of true wheels, etc. The machine itself is nothing more than an electric motor with extended arbors. I don't think it gets any simpler than that! Are you satisfied with your Ryobi?

[guycox]

I've had good luck with the OneWay wheel dressing system. It's a single diamod point that attaches to the wolverinve base.. Oneway also makes a wheel balancing system that have not felt I needed -- I'm running an 8" Delta that is at least 8 years old and has seen some heavy use in production turning shop before I bought it..

[dbhost]

Very true, Db, very true It makes me wonder if alot of the complaints and poor feedback received over grinders is nothing more than poor fitting wheels or out of true wheels, etc. The machine itself is nothing more than an electric motor with extended arbors. I don't think it gets any simpler than that! Are you satisfied with your Ryobi?

Very. It has features that I was very interested in. Specifically the magnifier in the shield and the work lights over each wheel. Cost was reasonable. I got it with one of those $10.00 off coupons Home Depot sends every now and then... I think the thing was under $50.00 before tax. I have WAY more in the Wolverine setup (bought the main jig new, all the accessories used), wheels, bushings, and the truing tool. Yes Oneway does have a dressing tool for the Wolverine jig setup, but the reviews I have read from users that have both the OneWay and the Geiger all prefer the Geiger as being easier to use, and providing more reliable results.

FWIW, if I had it to do over again, I would SERIOUSLY look into the Penn State 8" variable speed grinder, and 4 piece grinding jig set. http://www.pennstateind.com/store/LCGRINDSYS.html The only drawback I see there is lack of a worklight, and I am planning on grabbing one of those HF flexible neck worklights with a magnetic base to use on the band saw and lathe...

[bthorne]

I also have the Ryobi 8" grinder, set up on a HF cast iron stand. The Ryobi seems to work quite well. With the original wheels it wanted to walk across the floor a little, and after replacing them with Norton ones it tried to run across the floor. I got Oneway's wheel balancing jig: http://www.leevalley.com/en/wood/pag...26&cat=1,43072. After a few minutes of fiddling to install the weights properly, it fixed all the wheel balance problems. The grinder runs smooth as butter, and takes minutes for the wheels to stop spinning after shutting it off.

[dbhost]

and takes minutes for the wheels to stop spinning after shutting it off.

I know this is a dumb question, but I am on my 4th bench grinder, the first an old Ace hardware 6", then a Rockwell 6", then the Ryobi 6" and Ryobi 8", and they all take forever to spin down. Is that abnormal?

Every bench grinder I have been around seems to do that. I never gave it a second thought.

[gsmittle]

I know this is a dumb question, but I am on my 4th bench grinder, the first an old Ace hardware 6", then a Rockwell 6", then the Ryobi 6" and Ryobi 8", and they all take forever to spin down. Is that abnormal?

Every bench grinder I have been around seems to do that. I never gave it a second thought.

My little bit of experience is that it takes forever for grinders to spin down. This is based on my one and my dad's four back in the day.

g.

[gjat]

How do you true and dress a grinding wheel? Wouldn't you need a jig and crap? Isn't it easier to put on a new wheel?

[chopnhack]

Wow, Dbhost, I like how you spend my money LOL. Then Penn State is pricey, looks great. The Oneway makes sense, these wheels are not balanced when they are made, never thought about that before. I have a little difficulty spend $70 on a jig to true the stone though....I guess its better than buying a tormek though.

[dbhost]

Like I said, if you were close by, I would have you drop by and I would true the thing for you... I hated spending the $$.... It should be obvious I won't spend money I don't need to... I figure my grinder is very multi purpose anyway, and honestly, I had a couple of failed home brewed jig attempts... Which is how I bought the Wolverine... If you build your own jig, don't copy my attempts at using plywood. The stuff I used was from the BORG, and had a LOT of internal voids, which inevitably would show up where the arm broke...

I got the Wolverine jig on sale, and all the accessories, varigrind, skew platform etc... for pennies on the dollar used. I wouldn't have paid full price for it... I don't recall how cheaply I got the stuff, but it was somewhere in the neighborhood of 25 % of retail + shipping...

As a bare minimum, you are going to want the grinder (figure $60.00 or so...) and depending on what you want to do with it... you will probably want some white aluminum oxide grinding wheels ($21.00 + S&H each), and solid steel bushings ($10.00 + S&H each), IF you are lucky, the stones are concentric and square, and will run smooth, if not, like mine, you will need to true them, you can rig up some sort of way of steadying a regular diamond tip dressing tool and just shave it down until it is concentric and square. An inexpensive dressing tool runs about $20.00...

[chopnhack]

BORG ply

I got one blessed sheet from them that was so awesome I think I wrote about it here. I was in love, it was winter and the sheet was white birch....LOL But really it was that nice. First pic in this linke http://www.bt3central.com/showthread.php?t=49987

The other 2 purchases were just complete ripoffs. I would have saved money using their sheathing grade and a veneer!!