Anti vibration for 8" grinder?

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This grinder was fine when I had it on a wheeled dolly from Harbor Freight but that made it too high so I pulled the dolly out. Now the grinder walks all over the shop. I'm going to take the wheel and wire wheel off and start at that point. Put one back on and turn it in 1/4 turns and see if that'll make it run better. But do you have any suggestions for which rubber mat to go under it or feet with a 3/8" shaft? Couldn't find any of those online. Wheels won't work, the skirt around the edge is too close to the holes and the wheels will bind up. That's what I wanted to do but found out differently.

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Reply:Something doesn’t seem right to me. It must be out of balance or something.  The way you have it bolted to a cast-iron standIt should not be walking all over the shopMiller 211Hypertherm PM 451961 Lincoln Idealarc 250HTP 221  True Wisdom only comes from Pain.
Reply:Nvm...Last edited by N2 Welding; 11-21-2020 at 03:04 PM.Lincoln, ESAB, Thermal Dynamics, Victor, Miller, Dewalt, Makita, Kalamzoo.  Hand tools, power tools, welding and cutting tools.
Reply:It's walking because it's top heavy and the slightest vibration is being amplified. Possibly a chunk of 1/2" or 5/8" conveyor belt might help. Or just anchor the thing to the floor. I had one mounted on the old standard 22.5" truck wheel that would crawl around until I put 3 equally spaced pads on the rim so it would always sit in contact with the floor. 3/4" horse stall mat is good stuff too if your base is big enough to not be tippy.
Reply:Either true your stone, or put on a new stone.
Reply:wheel that is not true or is out of balance is also unsafe. True it up, if that doesn't stop it, then replace it.IMPEACH BIDEN!NRA LIFE MEMBERUNITWELD 175 AMP 3 IN1 DCMIDSTATES 300 AMP AC MACHINEGOD HELP AMERICA!“Freedom is never more than one generation away from extinction.We didn’t pass it to our children in the bloodstream".RONALD REAGAN
Reply:I have used rubber cut from a big truck mudflap. Be sure to use locking nuts on the bolts.
Reply:I took both wheels off and ran it. Ran fine. Then the wire wheel went on, I adjusted it in 1/4 turns until nearly all vibration was gone. Then the grinding wheel went on. The grinder walked all over the place even with turning the wheel in 1/4 turns.So I put a dial indicator on it and it was out of round by .020. I'll get a flat wheel dresser and see if that will true it up. Maybe if any vibration is left after truing it will go away with a rubber mat. I can't bolt it down, my shop is small and I need to move it from time to time. Since someone mentioned it, it's not top heavy. It just looks that way because of the angle my phone shot it at. That Burr King base weighs a lot.
Reply:

Originally Posted by N2 Welding

Nvm...
Reply:Is it just my eye or is that grinding wheel off center on the vertical axis?Ol' Stonebreaker  "Experience is the name everyone gives to their mistakes"Hobart G-213 portableMiller 175 migMiller thunderbolt ac/dc stick Victor O/A setupMakita chop saw
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Originally Posted by mla2ofus

Is it just my eye or is that grinding wheel off center on the vertical axis?
Reply:

Originally Posted by JD1

Nvm??
Reply:

Originally Posted by JD1

Maybe if any vibration is left after truing it will go away with a rubber mat.
Reply:

Originally Posted by mla2ofus

Is it just my eye or is that grinding wheel off center on the vertical axis?
Reply:Myself personally I think you may be going in the wrong direction. It needs to be bolted solid but you say you don't want that then you need some way of quick releasing a solid mount.A grinder is not something you want on isolation of any sort IMO. The more solid it is fastened to more base the smoother it gets. You don't want the stone to be moving while grinding for sure. Maybe pick a spot for when you are going to be doing a lot of grinding and install some recessed anchors you can put a couple bolts in quickly and remove when your done.Rubber under the base and anchored too may be another good way.  For portability without anchoring the rubber matt from Rural King or other farm store under the whole thing would keep it from walking.Last edited by danielplace; 11-22-2020 at 06:15 PM.
Reply:A thick rubber mat for putting under a treadmill or other exercise equipment would work. I use one to lay on on the dirt floor in my pole shed when working on stuff.
Reply:Check the wheel and the flanges for run-out.  True the wheel after checking.  I do not trust low-budget wheels.  Abrasive machining is great, but it can be dangerous if the stone flies apart."USMCPOP" First-born son: KIA  Iraq 1/26/05Syncrowave 250 w/ Coolmate 3Dialarc 250, Idealarc 250SP-175 +Firepower TIG 160S (gave the TA 161 STL to the son)Lincwelder AC180C (1952)Victor & Smith O/A torchesMiller spot welder
Reply:Well, I need a little more help - I'm evidentially doing something wrong. The small hose clamp keeps the diamond dresser running along the rest without going in and out with the wheel discrepancies. However, it's worse now than when I started. The surface is much smoother which makes it easier to run the dial indicator on it but instead of being off .020, now the high area is almost .030. The grinder vibrates a lot. And I am sliding the dresser back and forth, not holding it still in one spot.One thing i noticed after a while is that the rest is angled, not at 90 degrees. I tried to clamp a piece of flat bar onto it to get it to 90 but the vibration moved it around. I didn't even use it. So I'm going to temporarily tack it down. Therefore the face of the wheel is probably slightly angled which will straighten up when I tack the flat bar down.I've seen diamond point dressers and you buy a jig to run them with but that's too expensive and seems to me to be overkill unless I was using the grinder every day to make money. So those of you who have done this, what might I be doing wrong and what should I change?

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Reply:

Originally Posted by Oldendum

Check the wheel and the flanges for run-out.  True the wheel after checking.  I do not trust low-budget wheels.  Abrasive machining is great, but it can be dangerous if the stone flies apart.
Reply:Is the arbor in the wheel the correct size for the shaft of the grinder?Mike
Reply:Yep, 5/8".
Reply:Forget all that diamond dresser stuff.  Get one of these.

This is a pic of some POS thing from HF.  There should be more wheels in a good one.  But anyways......................this is all you need to true up a wheel.I run a grinder on a little mat, and true it occassionally................doesn't walk.If you actually have runout, hold the dresser at a position where it only partially contacts the wheel in the high spots.  Don't just shove it in there.  You have to kill the high spots.
Reply:A good dresser should have between 5-8 wheels on it, but ya get my drift.
Reply:I like a GOOD diamond dresser, but it may be "following" the runout of the wheel so it's not actually dressing the high spot down and just following the shape of the wheel. You also need to check the shafts for runout. I have never liked the idea of reversing the direction of rotation, nor do i think it's safe to face/true the sides of a wheel unless it's a wheel designed to be a "face" wheel. also make sure the cardboard blotters are in place and in good condition. The wheel type dresser might be a better choice until you get it trued.IMPEACH BIDEN!NRA LIFE MEMBERUNITWELD 175 AMP 3 IN1 DCMIDSTATES 300 AMP AC MACHINEGOD HELP AMERICA!“Freedom is never more than one generation away from extinction.We didn’t pass it to our children in the bloodstream".RONALD REAGAN
Reply:I use the single point diamond dressers myself... never liked the bar type like you posted...But like all the dressers you must make sure it is not moving in/out when you use them!!! at least if you want a nice true finish




Originally Posted by ronsii

I use the single point diamond dressers myself... never liked the bar type like you posted...But like all the dressers you must make sure it is not moving in/out when you use them!!! at least if you want a nice true finish

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Reply:Here's a better pic. of the Huntington style dressers. They have a few other styles as well.http://desmond-stephan.com/index.php...ngton-dressershttps://www.desmond-stephan.com/
Reply:Did you also use your dial indicator on the motor shaft?  If the grinder got knocked over at some point in it's life, then the shaft may be bent.Century buzzbox that I learned on 40+ years ago (was Dad's)Crappy Century 110volt mig 70 amp pigeon pooper.Lincoln Idealarc TIG-300
Reply:I got the difference down to .007 from almost .030. I found the low spot, marked it on the side, then vice gripped my dresser to the rest so it barely touched the highest spot. Ran the grinder until that was gone and worked my way down. The hose clamp wasn't near precise enough and although it rode on the edge of the rest that wasn't enough to keep it from following the high/low points and it would be completely impossible manually, at least for me. Vice grips did it. In order to get that down to next to nothing, I might have to have a jig where I could incrementally dial the dresser in. It's too hard to take a high spot out unless you have some way to lock the dresser down so it won't follow the contour. It's also tricky to tweak it closer without getting it too close while keeping it locked down unless you have some kind of dialing jig. Sometimes in the process I got it a hair too close to a high section and the motor startup wasn't strong enough to get it going so I had to help it manually until that spot ground down enough after a few revolutions. There's still some vibration which I'd like to figure out, but the grinder is useable now.I have one of those dressers with wheels and have used it on another grinder. It's OK for cleaning out the grit, removing grooves and taking a bevel out of the face but IMO completely worthless for truing a high spot out of the face. Not very precise.If I get bored this winter and need a project, I might try to make one of those jigs. I've seen one for the diamond point dressers but it and that dresser are probably more than I ought to spend for intermittent use.PS. I will try the dial indicator on the shaft, both sides. The wire wheel is a Weiler Vortec and has a little vibration to it but there's not much can be done other than rotating it.Last edited by JD1; 11-24-2020 at 11:04 AM.
Reply:I use a shaft collar to set my depth on the round dressing nubs. Gives you quite a bit more bearing surface against the tool rest.
Reply:

Originally Posted by JD1

Nvm??
Reply:I'm done.1) Got the runout down to .0032) Accidentally found that even at that, the wheel has a heavy side.3) Small vibration with the Weiler wire wheel plus the heavy side of the grinding wheel was combining to aggravate the overall vibration.4) Rotated the grinding wheel in 1/8 increments and found a spot that mostly offset the Weiler wheel. The Weiler wheel was already rotated to it's best position.5) No runout in the shaft. No vibration at all when the motor ran by itself.Some rubber washers and a rubber mat and it's good until I have to replace the grinding wheel. I'll look for a better grade then.