Need variable speed belt grinder?

[SHARPCO]

There are two reasons why a variable speed belt grinder is required. One is over-heat, the other is over-grinding. But....

1. Over-heat
: The heat can be controlled by the pressure as well as the speed. And we can often cool the blade with water(Of course, ice water is better). In addition, Bark River and Ken Schwartz said OK.(https://youtu.be/4cfCYb-Gamg) As you know, Bark River is one of the world leading outdoor knife maker and Ken is one of the masters of knife sharpening. 

2. Over-grinding
: In same belt, the amount of grinding can be controlled by the pressure as well as the speed. And besides, we can use finer belts. 

So I'm not sure the variable speed belt grinder is necessary for sharpening. 

How do you think about it?

[Ken S]

The Viel belt grinder is designed as a cost effective, quality tool. It is specifically designed to be able to work with furnace type motors the buyer might already have on hand. Good used motors should be plentiful and inexpensive. Just make sure you get the right size.

I would suggest you pick up an inexpensive used 1/4 or 1/3 horsepower 1725 RPM (or equivalent for your electric power) motor. Try full speed for a while. You may decide you don't need variable speed. Many users feel that way. Using an inexpensive used motor will let you decide at minimal cost.

Ken

[Cyrano]

For light-duty work, the WorkSharp Ken Onion Edition with Blade Grinding Attachment is a convenient and capable low-cost option which offers variable speed.

[SHARPCO]

For light-duty work, the WorkSharp Ken Onion Edition with Blade Grinding Attachment is a convenient and capable low-cost option which offers variable speed.

Hello Cyrano. 

I sharpen knives with Tormek and Work Sharp Ken Onion Blade Grinding Attachment. But I need belt sharpener that has platen so I ordered Viel S-5-M. The Work Sharp BGA is good personal sharpener but I have to use better machine because I'm professional.

[Cyrano]

Sharpco,

The addition of a platen would make the WSKO/BGA system more useful for me, too.

As it is, without a platen, belt flex significantly limits the geometries one can achieve using it. I chased my tail for quite a while attempting to put an acute apex angle on thick blade stock, until I learned that it is not possible.