Need help finding the right grinder

[btdust]

As of yet do not have a grinder in the shop. Need one to sharpen woodturning tools, along with one to sharpen lawn mower blades, axes, and anything else that might get dull. Would the slow speed grinder be best for all of these needs, or do I buy a variable speed grinder that ranges from 1750 to over 3400? Read somewhere that the Delta Variable Speed grinder 8" was giving some people problems. Any and all input will be appreciated.

Thanks, btdust

 

[DaveO]

A slow speed grinder will do everything a faster speed grinder will do but just slower. The advantage with a slow speed is there is less chance of overheating the metal and loosing the temper. I would recommend an 8" over a 6", as with the smaller wheels the hollow grind gets greater, and an 8" give you a little more wheel surface to work with
I have a dual speed 8" from Woodcraft,

I never change the speed. It works well and comes with some decent stock wheels.
Dave

 

[scsmith42]

Bill, this may be more info than you want.... but around the shop I use several different methods to sharpen items.

Items such as mower blades, machete's, axe's, etc, typically get clamped in a vice, and rough sharpened with a hand held angle grinder (I use 7" Makita for rough sharpening [such as this one:



http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200305673_200305673

For "maintnenance" sharpenings, I use a 4-1/2" version of the Makita to sharpen "on-mower". This sure beats the heck out of removing the blades!

Blades that are rough sharpened in the vise typically get a final sharpening using a 6" belt / 9" disc sander (slow speed Grizzly G1276) that is dedicated for metal working. Here is the model that I have:



The belt / disc sander is also used to sharpen chisels, drill bits (that are larger than my Darex sharpener will handle), carbide cutters, etc.

Precision tools such as drill bits, chisels, milling cutters, etc, receiving a final deburring with hand-held stones, like these:

http://www.jlindustrial.com/ADZ-06032E/SEARCH:KEYWORD/product.html

Less precise items such as axe's, etc, will receive a deburring with a hand held file.

An 8" bench grinder with a rough wheel on one side and a wire brush on the other is also in use - but rarely for sharpening (unless the item won't fit on the belt sander). The wire brush gets used ten times more than the grinding wheel, because I find that other methods outlined above are faster, more accurate, and offer better safety than the bench grinder. I use the wire brush for removing rust, scale, gunk, etc from bolt threads.

A 6" slow speed bench grinder with special wheels is dedicated for grinding tungsten tips for a TIG welder.

The WEK wet grinding machine in my tool cabinet has not been used in close to ten years...

My advice? - buy a hand held angle grinder (such as the Milwaukee model / Northern Tools pn 110312-1806 or 153396-0806), AND a slow speed belt / disc sander such as Grizzly model G1276 (http://www.grizzly.com/products/Combination-Sander-6-x-48-Belt-12-Disc-1725-RPM/G1276). You can use the belt/disc sander for double "wood - metal" duty if you clean the belts after using it for metal and before using it for wood. This will help keep any small metal particals from becoming embedded in your wood projects. Another option is to simply change belts / discs for metal versus wood work.

The 4" grinder has the nice ability to do "double duty" as a woodworking rough carving grinder if you add a Lancelot fine carving tool to it. (http://www.grizzly.com/products/Lancelot-Fine-Carving-Tool-22-Tooth-5-8-Arbor/G6692)

If you're on a tight budget, consider the Grizzly 4" grinder instead of the Milwaukee (http://www.grizzly.com/products/Angle-Grinder-4-/G5968)

Hope this helps!

Scott

 

[Makinsawdust]

For axes, mower blades, etc. I prefer high a speed grinder, file and/or sanders. For turning tools the slow speed grinder from WC is hard to beat in quality and price. I also use a 1" belt sander with 120 grit to sharpen alot of my turning tools. I just like the finish better.
Rob

 

[Gotcha6]

Scott, are you able to find emery cloth belts for your belt/disc, or do you just use an 80 or 120 grit belt?

 

[scsmith42]

Dennis, on the sander that I use for steel, normally I keep 60 - 80 grit on the belt, and anywhere between 150 - 220 grit on the disk. I'll use the disk for fine work, and the belt for rough work.

I find that the work platforms on the sander are easier to work from versus a 6/8" bench grinder. Usually I will sharpen a chisel from side to side, as opposed to from tip back. The side to side sharpening is easy on the disc, and safe.

About the only time that I'd use the WEK is when extreme precision is required on a wide blade - such as for a handheld plane.

If/when I need to sharpen a chisel with a bench grinder, I will usually use the side of the grindstone instead of the face. Moving the chisel closer to the center of the wheel provides a slower surface speed for sharpening and less chance of overheating the chisel. (same holds true on the disc sander)

By the way, I haven't mentioned it before but I always enjoy your posts. I've learned quite a bit from you.

Regards,

Scott

 

[junquecol]

My do everything grinder is a 6" dual wheel, 3450 RPM, that I bought from Lowes. I have had it for 26 years, and paid the princely sum of $29.99 for it. One day, I will be able to say "I got my money's worth." Only thing I have done to it is to replace the wheels a couple of times. I built myself a slow speed 6" grinder for hollow grinding chisels. The main thing to prevent burning of the steel is to keep a friable wheel on the grinder, and dress it regularly.

 

[Mike Davis]

I doo almost all sharpening with a belt sander and a diamond plate to hone.

I have belts from 40 grit up to 600 grit.

www.trugrit.com has fine grit belts.