Sunday, September 2, 2012

V3.35 - Let’s talk Bench Grinders

Ok, after a few detours, let’s get back to our ‘roots’ – which is not to say that I will not ever bust off on some more ‘passing thoughts’, shoot no. It’s just that there are a lot of folks who write about current events every day, but not so many that help folks with tools. I kind of like my slice of the pie. Anyway, keep reading… you never really know what might show up in here.

I would wager that most anyone who has a shop, or works in one, would be among the first to tell you that one of the most necessary tools in their shop would be their bench grinder. This may not apply for some specific woodshops, but since Toolsmartz is about ALL shops, we can cover it.

Bench grinders come in many different sizes and the major defining factor about them is the wheel diameter. Most people would not say, ‘yea, I have a ½ horsepower bench grinder’. No, they will be saying, ‘yea, I have an 8” bench grinder’. Even the bench grinder manufacturers set up their advertising literature in this fashion. The grinder’s horsepower and speed are somewhat of a secondary matter, after the wheel diameter, but don’t mis-understand, the horsepower and speed are critical factors when selecting the correct bench grinder, but what is usually seen is that as the wheel diameter gets larger, so does the horsepower. This allows the bench grinder to tackle harder jobs. The deal is, when you have a large item to grind on, you really need a decent sized bench grinder. My personal philosophy is that if you have a large (meaning 10” wheels) bench grinder and need to do a small job, it can handle it. On the other hand if you have a small (meaning 4” or 6” wheels) bench grinder and need to do a big job, you can’t…or if you try to, you may burn up your small grinder. So yes, when considering what bench grinder to choose, size does matter.

Another factor to consider is the bench grinder’s speed. This is also known as the RPM of the grinder. For most grinding operations, I prefer a speed of 1725RPM. Many grinders only come in a speed of 3450RPM, which is fine for many operations, but again, if you have a 1725RPM speed, you can pretty much always do whatever it is that you need to do. If you only have a 3450RPM grinder, I can promise you that you will overheat some items real fast. As I suppose you have gathered, my personal favorite bench grinder is my 10”, 1725RPM unit. It has no problem grinding small parts and it can handle all of my lawnmower blades without overheating them and burning them up.

Next week, we’ll continue this Bench Grinder discussion and get into some of the typical problems that you might encounter and recommendations for solving them.

Send your questions or comments to: and we’ll see what we can do to help you.

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