Contact Wheel Edges

Does anyone round the edge of your grinder's contact wheel? If so, why?

I have seen a few photos where it seems like the maker has done this.

It's fairly common practice, Kevin- it softens the edge for a smoother plunge cut, and also minimizes the occurrence of the dreaded 2" mark.

How do you go about doing this?

Is it a good idea?

I have read elswhere that it can be done with a router, but that seems a bit risky to me, and I don't have a router.

A coarse file while the contact wheel is running is one way. Jerry Hossum told me he used a coarse belt, turned inside out, against the running wheel. Someone else said they used a router with a rounding bit. Lots of ways to skin a cat.

While you are rounding the corners of the contact wheel put a crown in the face of the wheel, not much just enough to stop the 2" mark problum, belt will also track better, just use a large corse file. Gib

Hey guys for those of us that are new can you explain what you mean by the 2" mark?

There is a tendancy for those of us using 2" wide grinding belts to over-focus on what one side of the belt is doing (say, at the plunge cut, for example), while the other edge is cutting a nice divot in the blade 2" from where we are concentrating. This makes for scrap, since those gouges are usually deep enough to be impractical to remove without re-designing the knife.

Thanks that explains a lot. :d

I for one (I may be the only one) don't recommend cutting up that contact wheel in any way shape or form as the saying goes. With the way the contact wheels work. for me I guess they just knew what they were doing when they made them the way they are. At least why not use it or them as they are and see if it really is the shape they are that is creating a problem for you. To help with the plunge line drift your belt a little over the edge of the contact wheel. You can do the same on the edge of the platen if you are flat grinding. Some people do grind with 1" rather than 2" wheels and I wish I could afford to try that, but I believe crowning a large contact wheel can create all sorts of problems for an inexperienced grinder. If crowning on your main contact wheel is something you want to try get out the masking tape, maybe in several sizes, wrap your wheel and go to it. You will be amazed how long the masking tape will last. Crowning the idler wheel will really help to stop the belt from skating if you are doing some slack belt grinding. By the way, those contact wheels even small ones are very expensive in Canada. Frank

Don't mess up your wheel.
The plunge cut radius can be controled by running slack on the side you want to cut.(allow the belt to overhang just a little)
The crown should be on the idle wheel only.
A flat edged wheel cuts much straighter than a beveled wheel.
A worn wheel eats up belts quicker (the edges wear off).
I dressed all my wheels years ago. I have slowly been replacing them ever sinse. I have one grinder left with a rounded wheel, and it slings more crap back at me than any machine with the good wheels.
It has cost me more in time and trouble than the short cut was worth originally.
There is a reason they pay those engineers so much money to put that type of edge on thier wheels. It was designed to give maximum results and to last.
Once you cut the skin of the rubber, it begins to wear more quickly.
Just a thought from an old timer.Be warned.