Bench Grinder for plane blades and chisels

[tibi]

Hello,

I would like to ask for a buying advice for a bench grinder. What power should I aim for? And what is the most suitable type for plane blades and chisels? Grinding a primary bevel on stones is very tedious. Most types I can find have those fixed tool rests that cannot be adjusted to a specific angle.

or I can buy this, but the quality is dubious

or this

I do not want to buy Tomerk, as it is way too expesnive.

Thank you very much.

 

[--Tom--]

Grinders are fairly simple things and for occasional use most should be fine. It is worth putting a decent wheel on them if using for edge tools as they’ll grind much cooler.

Another thing to consider would be a small linisher

 

[tibi]

Grinders are fairly simple things and for occasional use most should be fine. It is worth putting a decent wheel on them if using for edge tools as they’ll grind much cooler.

Another thing to consider would be a small linisher

I also considered buying a small linisher, as you can set up a grinding angle easily. Are there any obvious disadvanages compared to a standard stone grinder?

 

[Fitzroy]

I bought one akin to the Bosch one but from Screwfix own brand. I knocked up a rest at the correct angle from some scrap metal bent in a vice. A bit agricultural looking but works ok for putting a primary bevel on. Lots of dipping in water to keep the edge cool.

 

[Stevebod]

I brought an Aldi "wet stone" grinder (looked identical to the Scheppach), a couple of years ago for £80, but it really was "low grade" so I sent it back and got a Record version assuming the extra £60 would make it better quality, but that failed when the motor casing split after 5 minutes use, so back that one went as well. To be fair the Aldi one would probably "do the job" if you are a casual user like me, and it did come with a few extras to allow sharpening of knives and scissors etc. which all tend to be "extras" from other suppliers. But I guess if you want something decent then you will be looking north of £250+..?
For my rather limited use I can't really justify the cost....

 

[--Tom--]

Benefits of a linisher are flexibility can go from a 36grit belt up to 2000grit to hog off material and then refine. A linisher will give a flat bevel, but I’ve never found the slight hollow from a bench grinder an issue in actual use, though some will tell you it’s “weak” if it doesn’t stand up just increase the angle…..
Disadvantage is cost - the machines cost more, they have more parts so more to go wrong, and belts are much more expensive than grinding stones.

Cheap 6” grinder, decent wheels, and practice on a chisel you don’t mind making a mess of. If you’ve never used one it’s worth intentionally bluing a bit of steel so you know how much time/pressure it took and what it looks like. Then try and never do it again!

 

[D_W]

inexpensive 6" grinder, but with coarse wheels and if you can help it, get something 350 watts or more in case you want to do some light grinding down the road.

Coarse wheels and a decent T-shaped dresser and you'll be good for a long time. No fine grit specialty wheels - fine grit is honing, not grinding and fine grit wheels create a lot of heat.

 

[tibi]

Thank you very much all. I am more inclined to buy a 375W Bosch version. Do you grind the bevel angle by hand or you have a tool rest that can change angles?

 

[spanner48]

You should ALWAYS do the final bevel by hand. Never let a machine wheel actually touch the feather edge; it will blue it almost instantly. Then the blade is useless until you've ground out all the blued material. I use a cheap Chinese one like your DSM, for the first bevel. Then the second bevel by hand on a 300/1500 diamond whetstone. Works OK on all but the finest scribing chisels, where I polish off the wire edge on a Black Hard Arkansas stone at around 4500.

 

[tibi]

You should ALWAYS do the final bevel by hand. Never let a machine wheel actually touch the feather edge; it will blue it almost instantly. Then the blade is useless until you've ground out all the blued material. I use a cheap Chinese one like your DSM, for the first bevel. Then the second bevel by hand on a 300/1500 diamond whetstone. Works OK on all but the finest scribing chisels, where I polish off the wire edge on a Black Hard Arkansas stone at around 4500.

I buy this grinder just for reestablishing primary bevel, as my blade bevels are rounded by freehand sharpening and they stop cutting, so I need to reestablish the 25 or 30 degree bevel. I do not want to touch a tip of the blade, as there is very little metal and I would burn it off.

 

[redhunter350]

Possibly more than you wish to spend but look at Robert Sorby ProEdge never regretted buying mine, also being a metalworker it has many other uses. Think of the cost as how much per year it costs !

 

[tibi]

I have just purchased the Bosch grinder. It is strong enough and should provide better quality than other cheap models. I just need to make some tool rest, that will alow me to set up correct angle.

 

[Limey Lurker]

I clamp a small square under the blade, check that the angle against the wheel is correct, then switch on and with very little pressure against the wheel, move the assemblage back and forth , checking very carefully. (The guards are off while taking pics) Once you are satisfied that the angle is correct, the blade can be marked for subsequent regrinds.

 

[clogs]

I bought a slow speed 8" grinder...it was £25 but 3 phase....cant here it running.....

best use a white stone for anything other than roughing .....and a pot of cold water close by.....

 

[D_W]

Thank you very much all. I am more inclined to buy a 375W Bosch version. Do you grind the bevel angle by hand or you have a tool rest that can change angles?

you can achieve grinding a million ways. I agree with the comments above about not grinding to the edge, but you can get touch (with a coarse wheel, especially) to grind the entire edge off and not burn it.

I grind with the rest at 90 degrees and get close to the primary bevel and just refresh what's there, leaving a tiny bit of the edge. The real issue with grinding the edge off is that you have to hone it back, anyway, as the coarsely ground edge gets beat up by a grinding wheel - better to leave it both for the fact that it does take some learning to grind it off without bluing, and because it's a waste to have to hand hone the deep grooves off *plus some more* to remove impact damage that occurs deeper than the groove.

But, you can make your own rest, buy a grinder with a good two piece rest, or use a 90 degree rest and a stop, or use the rest at 90 degrees as I do and no stop (this is fastest, which is why I do it - but I grind a lot to make tools, so refresh grinding to sharpen is sort of an afterthought).

Whatever you do, give yourself the chance to learn it and don't be discouraged by something not working right the first time (my first comment about a coarse wheel and a dresser will buy you a lot of latitude to learn - a 24 or 36 grit dressed wheel will grind as cool as anything you'll find short of a wet wheel or ceramic belts - the later two are either expensive or require something expensive to make use of them, as in, ceramic belts are really intended for very high speed belt grinders).

 

[okeydokey]

For what its worth some years ago I bought a Fox Fermi version of the Scheppach, same thing didn't get on with it also a bit flimsy - I ended up with a Record Power WG250 10" the same but better all round. Didn't like it either (the wet stone whetstone are slow) so put it away and used other sharpening methods just found it again and its ok to use. But wouldn't buy one again.
If you found it necessary you will be able to buy a leather disc/wheel to replace one of the grindstone wheels to hone an edge

 

[tibi]

For what its worth some years ago I bought a Fox Fermi version of the Scheppach, same thing didn't get on with it also a bit flimsy - I ended up with a Record Power WG250 10" the same but better all round. Didn't like it either (the wet stone whetstone are slow) so put it away and used other sharpening methods just found it again and its ok to use. But wouldn't buy one again.
If you found it necessary you will be able to buy a leather disc/wheel to replace one of the grindstone wheels to hone an edge

Hi OkeyDokey,

I always hone an edge on a 10 000 gritstone or strop. No need to do it on a wheel for me

 

[okeydokey]

Hi tibi thanks
Ive recently started using a strop which in my case is a 80mm wide hardwood offcut with a leather offcut spray glued on top with rough side of the leather upwards.
There is a fine leather handbag workshop near me so I bought (very cheaply) an offcut/scrap strip with markings - it had a leather defect bad enough not to be used on an expensive ladies handbag. So I have a high quality Italian leather dark blue strop