Surface Grinder Electrical Problems (RESOLVED)

The wheel I was using was an Norton A60 grit wheel. It's listed as 32A60-HVBE, meaning it is a 60 grit wheel (medium), fairly soft, and it's grains (Aluminum Oxide) are vitrified. Am I right by assuming that, since it is a fairly soft wheel and of a medium grit, it should be dressed often? How long should I let the spindle run prior to dressing? Also, what would you recommend as a coolant? I will try sparking out again. Hopefully, with a bit better understanding of how to use the grinder, sparking out will be a bit more effective than it was when I first tried it...
 
Trim Microsol 585xt has been a good coolant for me. Nathan Carothers recommended it a few years ago, as easy to work with and clean up, not too funky, and not needing much in the way of sump maintenance. That was my experience, as well.

It did make a big difference in terms of reducing warp in grinding thin stuff. Also it keeps the dust down, which is great!
 
xXBackyardCrafterXx said:
The wheel I was using was an Norton A60 grit wheel. It's listed as 32A60-HVBE, meaning it is a 60 grit wheel (medium), fairly soft, and it's grains (Aluminum Oxide) are vitrified. Am I right by assuming that, since it is a fairly soft wheel and of a medium grit, it should be dressed often? How long should I let the spindle run prior to dressing? Also, what would you recommend as a coolant? I will try sparking out again. Hopefully, with a bit better understanding of how to use the grinder, sparking out will be a bit more effective than it was when I first tried it...
Click to expand...

You want a soft wheel because you want the edges to break down as you're grinding, exposing new cutting surfaces. In flat grinding, it will actually need to be dressed less often than a harder wheel, where a hard wheel will load up and stop cutting. 3 to 5 minutes should be plenty. I prefer 100% synthetic coolants especially in machines that sit without being used often. They tend to resist bacterial and fungal growth better than semi-synthetics and far far better than soluble oils. Keeping way lube and other oil out of your coolant will also help this.

Harder wheels are better for form grinding, when the form of the wheel is important and you need it to hold it's shape. If I were to recommend a grinding wheel to a knife maker who only wanted one wheel it would be a 40 grit Radiac. They resist loading and produce a good finish, and are open pored so they run a bit cooler than others.
 
Salem Straub said:
Trim Microsol 585xt has been a good coolant for me. Nathan Carothers recommended it a few years ago, as easy to work with and clean up, not too funky, and not needing much in the way of sump maintenance. That was my experience, as well.

It did make a big difference in terms of reducing warp in grinding thin stuff. Also it keeps the dust down, which is great!
Click to expand...

The tray that the magnetic chuck rests on is only 3/4" deep or so. How would I keep the coolant contained and from sloshing around and ending up on my floor? I'm assuming I would have a pump and some sort of Kool Mist system supplying the coolant to the workpiece? Or could I just spray it on with a spray bottle every few passes....

kuraki said:
You want a soft wheel because you want the edges to break down as you're grinding, exposing new cutting surfaces. In flat grinding, it will actually need to be dressed less often than a harder wheel, where a hard wheel will load up and stop cutting. 3 to 5 minutes should be plenty. I prefer 100% synthetic coolants especially in machines that sit without being used often. They tend to resist bacterial and fungal growth better than semi-synthetics and far far better than soluble oils. Keeping way lube and other oil out of your coolant will also help this.

Harder wheels are better for form grinding, when the form of the wheel is important and you need it to hold it's shape. If I were to recommend a grinding wheel to a knife maker who only wanted one wheel it would be a 40 grit Radiac. They resist loading and produce a good finish, and are open pored so they run a bit cooler than others.
Click to expand...

I will look into getting one of these wheels for sure. Their site was a little difficult to navigate, but I found a list of their wheels here. Of the first five, which would you recommend?
 
Travers must be down but something like this wheel spec: RAA46-I2-VOS

For coolant, you'll need a drain hose from your table to your coolant sump, there should be a hole in the left side somewhere for one. Most grinders have removable sheet metal guards that are 2-3" tall that just slip into slots or tabs at either end of the table to help contain spray.
 
I just checked and I couldn't find any sizable holes on either end of the table. The only holes I could fine were some 1/8" holes drilled 1/2" up the front side of the table. It appears the very end of the table can be removed, but that is where the band that moves the table connects to it. I suppose I could always drill a hole in the bottom of the table...

For the wheel, I'm having trouble finding ones of the I2 variety, but from the looks of it, H800 is equivalent to I2. Is this correct? I found one here , eleven spaces down. Does that look right?

I have a little cheat sheet that tells me all the meaning of all of the different numbers and letter on the wheels and it has a list of all the different bonding methods (i.e. Vitrified, Silicate, rubber, Resinoid, oxychloride, etc.). What are the different applications for these ways of bonding and, in your opinion, what bond type is best suited for the work knifemaking entails. In your suggestion, you said the VOS-Vitrifies, Oxychloride, Silicate. Why this bond in particular? I'm not well versed in this and I want to be able to understand why we use wheels with certain characteristics for a task.

A little off topic, but for Way oil, I was told by the (incredibly awesome) people who gave me the grinder that I could use detergent free oil from Advanced Autoparts or NAPPA. I don't recall the viscosity he mentioned, but does this sound right? I know specially formulated oil would be ideal, but I don't really have the money to be running out and buying special spindle oil and way oil if I can get by with a cheaper alternative that works well...
 
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40 weight will work.

Nearly all aluminum oxide wheels in common use are vitrified bond. Remembering why really stretches my memory to trade school as that was the last time I gave it any thought. I remember going over it in a class but not the reasons why.
 
Alright, so 40 weight, detergent free oil. Sounds good :thumbup: Thanks for the help! I will have to finish a few knives and then I'll get that wheel and see if it does me any good. That hidden tang I've been working on on my Instagram should be finished up soon!
 
That's 40 weight for the ways, for the spindle you need to use something a lot thinner. I like light turbine oil in a pinch. But Mobil Velocite 10 would be a good place to start, if buying a gallon of the right stuff. If you have or can get a manual for your grinder, it will likely recommend oils.

My grinder specs a spindle oil of 100 Saybolt seconds at 100f, which is a good match for the "budget" gallon at the bottom of this page at McMaster Carr...
https://www.mcmaster.com/#circulating-oil/=16af4ud
 
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I should have checked McMaster Carr from the start- they have damn near everything :rolleyes: $27 for a gallon isn't too bad, I would imagine that would last me a while. I'll try picking some up soon. Thanks for pointing me in the right direction!
 
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