Grinding wheel question

[ieezitin]

Hello

I have just built a Tool grinder and i now need to learn about grinding wheels. 

I have a spindle that goes 4800 rpm, my primary grinding will be HSS tool stock and i need to be able to grind on two faces of the wheel perpendicular to each other, i am interested in the cup designs the spindle dia is 1/2''.

I currently have a Ruby red stone on there and it Burns quickly. This machine will be grinding lathe and shaper tools only so i don't need a mirror finish but a finish that will hone good.

All suggestions and grinding tips are welcome.

thanks for your help.

Anthony.

[PixMan]

Look for the white aluminum oxide wheels, from Norton (St.Gobain) the grade is 38A. They are the most commonly used ones on hardened HSS. Very free cutting and friable, they do break down and need to be dressed more often than the gray 32A or 32AA aluminum oxide, but they rarely burn work.

One caution is wheelspeed. Many grinding wheels are rated to 3600 rpm, though in smaller diameters that should be higher.

Grit size, start with 46, have a 60 on hand. For extra fine finishing an 80 grit might be good, though I rarely need to use that fine a grit.

HTH

Ken

[EdK]

Anthony,

Can you post pictures of your grinder? I'm sure a few of us would be interested in seeing it.

Thanks,
Ed

[ieezitin]

Pix Man  

thanks for your advice i will let you know what i find.

Ed

here you go...


its original life started as a Valve Grinder






Now i needed to modify it, i started with a aluminum table to hold the fixtures 


 










This three axis spindle was purchased off Ebay, it has a threaded spindle nose 1-1/2 x 8 tpi same as all my lathes











here is a shot of me tinkering with it to figure out all the angles i need, this is giving me ideas on affixing the fixture





here is a shot of my first 60 degree thread forming tool with the correct side relief angles for the helix angle, notice the burning of the Ruby red wheel






a top shot of the toolbit




A depth stop was needed





i made another fixture for it




i think you get the idea





on the rotational axis i had no way to gage the angle i was turning it to so i made a graduated dial for this out of aluminium with a pointer









I am getting there.





now i need to solve my grinding wheel problem....   thanks....   Anthony

[DaveH]

Nice looking tool grinder  Anthony
 
DaveH

[f350ca]

I was given a valve grinder a few years back, been collecting dust ever since. Nice use. Thought about making a drill sharpener out of mine.