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Thomas Kila
04-08-2009, 5:58 AM
I keep hearing that a slower grinder speed is recommended for turning tools. However, while checking out Oneway's site, they recommend grinders with 3425 rpm. What do you all say?

I've been using a WoodCraft 1725 rpm 8" grinder for the past few years. I paid around $80 for it. The wheels are badly out of balance and I've already decided on "going-for-broke" (:eek:) and purchasing a Baldor 8" grinder.

If I purchased the 3600 rpm 8" Baldor, I could save $100 in shipping costs, as the company here already has that model in stock. But if I want the 1800 rpm grinder, then I would have to pay about $1 per pound for shipping. (The unit weighs around 99 lbs.)

Any suggestions will be greatly appreciated.

Bob Hallowell
04-08-2009, 6:48 AM
This question has been argued over many times here. Some believe 1800 is better because it cuts slow and you remove less steel. I only have a 3450rmp grinder It's what I learned on and I can do light touch up's without any problems.

Bob

robert hainstock
04-08-2009, 7:01 AM
I have a six in 3600rpm, and an eight in slow speed which I usefor various grinds. the slow speed is "kinder to my tools, and remove needed steel quickly. I prefer it for most applications. :)
Bob

Steve Schlumpf
04-08-2009, 7:08 AM
Thomas - personally, I would keep using the slow speed grinder that you have and put my money into new 'quality' wheels and the Oneway balancing system. Makes a huge difference!

Greg Haugen
04-08-2009, 7:14 AM
I agree with Steve. You've used the 8" slow speed for a while now, why change speeds?? One isn't necessarily better than the other, it's personal preference and you've been using a slow speed. I also like the idea of new wheels. I've never used the balancing system, good quality wheels usually don't need it. On the other hand if you want a new grinder, than buy a new grinder. I've been using the Woodcraft 8" Slow Speed grinder from day one and still love it.

Bob Haverstock
04-08-2009, 7:46 AM
Thomas,

It's your nickel, you get to decide how to speed it.

I really like my slow speed. I forge many of my tools out of carbon steel, too much heat created my grinding retempers my steel at a higher temperature. The result is a softer cutting edge. I'm aware that I'm not mainstream on this topic.

Keeping balanced wheels on the grinder, keeping them clean, and well dressed will minimize heat generation to some degree.

I would consider upgrading the wheels and keeping the slow speed.

Bob

Gordon Seto
04-08-2009, 7:48 AM
I think if the grinder is mediocre, then slow speed is better. When the grinder is running smooth, you can have good control even at high speed. You can't write with good penmanship on a galloping horse back; you can't have a smooth grind if the tool is bouncing off the wheel. If you are taking too much steel with high speed grinder, then you should using lighter touch.
I have upgraded to the heavy duty Delta from the WC slow speed grinder with Oneway balancing system; also tried on other member's extremely smooth running high speed grinder. I would trade for the smoother running high speed (he got it used generic brand) any day.
For me, I would use the $100 towards the best wheels. The SG wheels from http://www.woodturnerscatalog.com/store/Sharpening___Grinders___Wheels___Norton_SG_Wheel__ _norton_sg?Args=
can't use Oneway balancing system. It was explained by CSUSA that the wheel density is so uniform that balancing system won't make them better.

Richard Beuker
04-08-2009, 8:01 AM
I have a two speed 8" grinder. I seem to always go to the slow speed.

Jim Becker
04-08-2009, 8:42 AM
I use the higher speed grinder with no problem...but I've also learned to use a "light touch". Sometimes folks new to sharpening are better served by the lower-speed grinders. But in the end, it really doesn't matter...the end result can be the same with the right technique. Far more important is using good wheels that are in balance and true...

Wally Dickerman
04-08-2009, 11:44 AM
I switched from a 6 in. high speed grinder to the Woodcraft slow speed grinder. It wasn't as big a switch as I thought it would be because of the difference in surface speed of the larger 8 in. vs the 6 in.

I think that the slow speed works well with the use of a sharpening jig because you are only touching up the grind instead of regrinding when you sharpen.

I agree with those who say that you might be better served by replacing the wheels on your present grinder with better quality ones.

If the wheels on your Woodcraft grinder weren't wobbly when they were new perhaps they are now because they haven't been properly dressed. That should be done frequently with a good diamond dressing tool.

Wally

Bernie Weishapl
04-08-2009, 12:22 PM
I like a slow speed grinder. I agree with Wally if the grinder has been working then I would get some new grinding wheels for it. It may be that they could be out of round if not dressed or haven't been dressed in a while.

Ken Werner
04-08-2009, 1:13 PM
My understanding is that HSS turning tools will not be harmed by high grinding temperatures. But chisels and plane blades will. I use the woodcraft slow speed grinder for all uses, and like it very well. The wheels that it came with are fine by me.

"Gary Brewer"
04-08-2009, 2:55 PM
Thomas: I have had the 1800 rpm Baldor grinder for a year now and like it a lot. It killed me to spend so much money but there didn't seem to be a middle of the road alternative. There does not seem to be a sweat spot in the grinder alternatives like there usually is in other types of tools. It's one of the last American made pieces of equipment you can get for woodworking. I'm glad I got it but most people I know have the WC grinder. When they go bad they throw them out and get another. I'm sure the faster speed can be worked with but it isn't as forgiving as the slower speed especially for a beginner like me. If you search on line you will find quite a variation on the Baldor's price.
Gary

Jeff Nicol
04-08-2009, 3:32 PM
Buy what you like or use what you have, but learn how to use the tool no matter what the speed. Just like with a woman a gentle and a soft touch will win everytime!

Patience is the key to perfection..................Maybe!!

Jeff

Thomas Kila
04-08-2009, 7:45 PM
I am very grateful for all responses. Based on these responses (and other factors), I went and purchased the 3600 rpm Baldor. Not only did I save the $100 in shipping charges, but the 3600 rpm version I purchased was an upgraded version from the 1800 rpm model, and the salesperson sold the upgraded version to me for $157 below list price. (This price was actually lower than the sales price for the 1800 rpm model - before shipping.)

(As for the pic police - I will take photos as soon as I set it up...) :)

Thanks again!