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antman
14th August 2003, 05:48 PM
Hello everybody,
I am in the process of researching everything before launching into the world of woodturning. I have been following a number of the posts and have managed to decide on a MC 900 lathe, some P&N tools, probably a Nova chuck (too many nasty chuck stories not to go for one!) but have drawn a blank with tool sharpening.

I do not have a bench grinder which is probably an important item. Is there any difference in grinders that other members are using? Is the no-name, mitre 10 cheapy any different to the $169 carba-tec ginder? Are any wheels better or more suitable than others for tool sharpening?

I know you get what you pay for but savings made on the grinder can be used elsewhere.

Any thoughts out there?

Thanks in advance,
Anthony

Mr. Minimax
14th August 2003, 06:26 PM
Hi there,

I went to a sharpening session by Les Miller (Aust. Woodworker) at the WWW show in Adelaide and he highly recommended the Ryobi 8" grinder - NOT the 6" $110 at the show
He said to fit it with a 1" white wheel.
Then obtain a veritas toolrest - available from Mik approx $80
Next piece of advice - grind the tool by just very gently (like a butterfly kiss) bringing it up to the stone. He claims that this will not allow the tool to overheat.
Then he hones on a diamond stone - EZI Lap (?) about 20x75
$119
He used a shop made honing guide consisting of a block at the required angle sitting on "sleds" which fitted on either side of the stone. Looked very easy and he was swearing by it.

This must be sharpening method 999 I've read about/seen.
I'm sure they all work - if done with sufficient care.

Sir Stinkalot
14th August 2003, 08:23 PM
I looked and looked and looked for bench grinders a few months ago ...... I ended up with a GMC 200mm (8"). Reasons ......

1. Price.
2. 2 year warranty.
3. Size for price.

I was going to go for a better name unit such as the 6" Makita (about the same price as the 8" GMC) but then I though about it for a second ..... I really wanted to go for 8" as it will keep the tool cooler, reduce the wear on the wheel and it can put a better profile on the tool ..... I decided that putting a turning tool upto the wheel really wouldn't put much load onto the machine so it isn't like I was going to work the guts out of it.

With the limited use for sharpening tools only I think that the GMC will last a lifetime and thats why I went for it.

As for the wheels .... get rid of the grey wheels and replace them with the white wheels ..... two grits if you have the spare $'s or if you are like me I just got the finer wheel to start with as I was looking at touching up the edge of the tool more so than reform it.

As for the tool rest ..... again I would save the $'s and get the $40 model featured under "sanding and grinding'" on the following site,
Carrolls (http://www.cws.au.com/)

A review of both this model and the Veritas model in one of the wood mags a few months ago basically said that the Veritas had a better finish .... but it had a smaller rest area and didn't come standard with the mitre guide, they really couldn't justify the extra $40 nor could I.

So there you go, I have almost finished my long winded reply .....

Rough costs

Grinder GMC 8" $100
White Wheels $25 (Check your prices I have been stung :D)
Tool Rest $40
Sharper tools .... Priceless ..... for everything else there is always next pay day.

gatiep
14th August 2003, 08:29 PM
Hi Anthony,
My 2 d worth....
Any reasonable grinder with a 1 " x 8" white stone is ample. The 6" stone is too small and makes getting the angles right a bit more tricky.
As for jigs, a very practical and eazy to use jig is made by most club members.....a few pieces of square tubing and a bit of flat bar , a hacksaw and a welder , or a mate who can weld it , is all that is required. I can always scan diagrams for you.
The gentle kiss bit is important and just to be on the safe side keep some cold water for quenching handy.
I am not sure that honing is really necessary, as the bit of burr , especially on carbon steel tools helps with cutting. Really for the novice I personally doubt the value of honing . There are small diamond hones about $19 for a set of 3 which can be used to hand hone the odd tool if you really want to.
Happy turning.

q9
14th August 2003, 09:09 PM
It is amazing the number of people that grind too agressively when they don't need it. To be honest, when resharpening turning tools, if you need to use water, you are doing it way wrong. I grind, remove burr, then use. I don't hone.

I made a simple rest from a few pieces of wood and a large bolt with a wing nut. I do agree that some of the other jigs make it easier, and more fool proof, so possibly a good spend of some dollars.

river rat
14th August 2003, 09:42 PM
Antman,
For what it worth here is what my partner and I use. 10/5 inch white (200 grit) combo grinder by delta 23-700. The 5 inch wheel is dry 3450 rpm and the 10inch wheel is wet 70 rpm cost is $149.00 on amazon . com. The large wheel is great for sharping with out over heating tools.

River Rat

Zed
15th August 2003, 09:31 AM
Hi,

I've got an Super tools generic 8" which is great - takes about 5 secs to get to operating speed but who gives a ?. I think that what has been said pretty much covers the lot of what you need.

Just like the women say - 8" is ample, 6' is too small and 10" is to serious

I understand that coarse soft wheels are the best (White or pink).

When you buy your grinder get the soft wheels at the same time for a discount and also get a wheel flattening tool so that your face is nice and square.

If you cant be bothered dicking around making a jig you can buy one from carbatech for $35 which has an adjustable fence and bolts straight onto your grinder - easy peasy.

Importantly make sure your grinder is securely fixed so something solid - so many blokes I know have it resting on a bench and thats it - one guy holds it down with a g clamp. the amount of kinetic energy in a spinning grinder can be farging dangerous - be careful.

never use a cracked or chipped wheel - i've seen one case where a dickhead at tech chippped a wheel and it shattered and ended up in the class room next door - just like in the cartoons where the coyote leaves a hole the shape of his body in the canyon!!

Lastly never stand directly in front of your grinder when you turn it on - stand to the side and let it speed up before you commence operations - the point being that wheels shatter when they reach the point of resonance. To test the resonance point put a golf bucket or glass of water on the bench with the grinder and switch it on you'll see ripples in the water as it starts whcih thent settle down as the wheel reaches full speed - the period where the ripples are greatest is the point of resonance - this is the peak danger period for you as the operator.

If you're a newbie take care - the grinder in the hands of a dickehead or the inexperienced is one of the easiest ways to damage your most important tools - your hands. When I was an apprentice prosthesist I was sharpening a gouging tool on an industrial 12' machine (Truely an awesome beast) and was not shown how to do it properly so with the enthusiasm of youth I just got stuck in - my thumb contacted the wheel for no kidding a farging nano-second and i lost a knick of skin in the shape of a "V" about 3mm deep the thick end was about 5mm across - I wasnt even pressing hard - if i WAS it would have chewed my whole farging hand off!!!

Sturdee
15th August 2003, 12:30 PM
Zed,

Thanks for the good advice. I'll stand aside of the grinder from now on when I turn then on.

Peter

Zed
15th August 2003, 04:43 PM
wise move. I wrote a sign on my grinder bench that sez "stand aside untill speed reached" - not for me (I know...) but for SWMBO and other ittinerant family members.

antman
15th August 2003, 09:29 PM
Hi all,

Thanks for your advice. I happened to be in our local hardware store today and I got talking to the guy there. He said that next week if I went to Ag Quip (A huge agricultural show in Gunnedah) I'd get a bargin. After a bit of talk he offered the 8" GMC grinder for $75 instead of $106 so I thought - Bargin! I will now order some wheels and that should see the sharpening sorted.

The rest is history! A friend from the high school (who just happens to be an industrial tech teacher!) is going to give me lessons in sharpening so all is good!

Thanks again....
Anthony

DavidW
15th August 2003, 10:35 PM
OK thats it I'm off to find some . No way I'm going to sleep with that image etched on my memory.

Red neck
15th August 2003, 11:16 PM
Looks like a split person(ality) to me!:D

gatiep
16th August 2003, 12:39 AM
The person in the striped top looks like a candidate to be rescued ( wow) when some hot sparks fly off that new grinding wheel into that top. I am moving my shed today....to find some of THAT passing traffic!
Perth woodshow is going great guns....today was extremely busy.
Happy turning and a striped weekend!

Grue
16th August 2003, 06:26 AM
Getting back to seriousity, Norton have a good page or six on saferty with grinders, grinder hints etc.

Very abrasive lot are grinders, don't let them rub you the wrong way.

As s starting point check out http://www.nortonabrasives.com/industrial/safety/OSHA.asp

Grue

Gino
16th August 2003, 07:58 PM
My what big balls you have doorstop.

G

Sarge
20th August 2003, 08:59 PM
Stinky,

I have looked at the GMC sharpening grinder at Bunnings and I just cant work out how you can use the white wheel effectivly when it is on the back of the machine and there is no room to set up any sort of tool rest. Is there something I am missing when I look at it ???

I just can't figure out how it can be used

antman
21st August 2003, 09:56 AM
Hi Sarge,

I suspect that Stinky might not have been looking at the grinder with the sharpening attachment. I noticed it as well when I was in the hardware shop. I went for a standard 200mm GMC grinder and ditched the grey wheels and put the white wheels on as per Stinky's recommendation. This grinder somes in at around the $100 mark, I think the grinder with the attachment was an extra $40.

There you have it. Incidently, Thrifty Link Hardware have the grinder for $89 in their father's day catalogue and Mitre 10 have it for $99. No idea what Bunnings want, they had a different model to the one I found for $149.

I'm not intending to answer for Stinky here but this is how I understand it. Correct me if I'm wrong.

Cheers,
Anthony

Sir Stinkalot
21st August 2003, 01:28 PM
Hi Sarge,

The model that I was speaking about is the BG200. I hadn't seen the other one before but I still wouldn't go for it. I am verry happy with the BG200 for around $100 as mentioned earlier.

GMC (http://www.gmcompany.com/50_bench%20grinders.jpg)

Stinky.

Sarge
23rd August 2003, 02:04 PM
Thanks for the info, I did look at getting a normal grinder and changing the wheel to the white ones but I was under the inpression that the 2000 odd rpm they turn at might be to fast. I was looking at the grinders that had two different wheels at two speeds, something like 3000 and 70 rpm. Is this idea not right ?? Should I be looking for a white wheel that turns at high rpm ??

BTW, I already have an old Skil bench grinder that I use as a bench grinder, I'm looking for something just to sharped my tools

I don't mind spending the extra dollars if I get the right tool for the job