CBN wheel - first impressions

[bellyup]

G'day All,
Don't you just love it when you buy something on spec. and it exceeds your hopes?
Well, I missed the diamond sharpening wheel purchase of a year back or so and have stuck by my 6" grinder with out-of-balance white wheel and over-heating motor.
Grinder envy won and I went looking for a better set up than was current.
D-Way Tools in the U.S.( no vested interest) had both diamond and CBN wheels for sale, the CBN being only $20+ more than diamond. The CBN wheel (and 2 gouges) arrived and I fitted it to the new 8" grinder then set up the Woodcut Tru-Cut jig to suit....... well, let me tell you , it's the best thing I have bought this year, galaxies ahead of the 6"white stone wheel.
I haven't used a diamond wheel so I can't comment on the performance between the two so my observations are limited to what you read.
I was worried that the finest grit (180) I had ordered would be too fine, but no problem there - this thing can remove an awesome amount of tool steel very quickly.I would think you could totally change your grind in 2 minutes should you desire.
Details:
The wheel surface is 40mm wide.
Wheel weight is about 2kg - (so some interia startup problems on low power machines probable.)
Bushing, fit and balance were perfect.
Cost - $185 plus post

Run-on with the grinder was so long, I had to write in Texta on/off to make sure I had actually turned it off.
If there is one critisism, it's that there is a resonance or vibration that occurs when a tool is being ground away from the dead centre of the wheel - mind you , nothing like a stone wheel, it's just that when you grind in the centre of this wheel it is so smooth you notice when it isn't.

Proof of the pudding: These photos are the remains of roughing and turning a Gidgee bowl.
For me, 182881

182882

182883

182884

This wheel turned my tools into another class. Tools used were P&N 1" roughing gouge, Hamlet 13mm bowl gouge ,1/2 " D-way spindle and 13mm Woodcut gouge. I have never had "curlies" from Gidgee before.:no:
I know some of the blokes had a problem with their diamond wheels with knowing "when" the edge was actually being ground. I didn't have that problem, there are some sparks visible when grinding - no problems for a pleb. like me
Maybe you don't need new steel, maybe you just need a better wheel??? I know I did.
I'll let you know what I think in a month or so if/after the gloss has worn off.:-
Bruce

[China]

Glad to see you are happy wtih it diamond a cbn are the norm in the sharpening industry cbn being prefered for steel, if you had the ability to run coolant you would get a almost mirror finish. It is only recently that these wheels have become economic for the home user not so long ago the cheapest cbn wheels were in the $4-500 range

[vk4]

CBN Wheels are available in Australia , I believe from PFERD Abrasives,

They would probably be a special order, I worked for PFERD for 3 years and never sold 1.

You can find branches in all state capital cities, they do not sell direct but will direct you to the nearest distributor to your town.

Jeff

[NeilS]

Thanks for the review, Bruce.

Tempting, very tempting!

Have you measured for any run-out to see if that vibration away from centre is from any out-of-round away from centre? Just lightly running a carpenters pencil across the face of the wheel while its running may show up any irregularities.

[Ed Reiss]

Another toy Bruce? :2tsup::2tsup::2tsup::2tsup::2tsup:

[rsser]

Interesting.

40mm width is a plus.

Maybe not enough backing alloy to support the full width?

[vk4]

What is the abrasive Grit spec of the wheel?? it looks to give an excellent finish, and obviously an excellent edge.
Jeff

[bellyup]

Neil ,
Good question about the out of round- I'll give your pencil idea a go tonight - to the eye it runs beautifully.

Ern,
The wheel is not lacking in weight, that's for sure. Given that the wheel is 40mm wide, there is less than 20mm either side of the centre line so it's a bit hard to know. The base the CBN is attatched to is fairly beefy. The fit onto the grinder shaft was a perfect ,snug, push fit. Dunno.
As I mentioned - it isn't bad, just noticable.

Ed,
My best toy for a long time me thinks!! should have upgraded long ago - I actually enjoy sharpening now :oo:

[bellyup]

G'day Jeff,
They come in 80 and 180 grit, I opted for the 180. Surgically sharp and very fast
Can't really think why you would need the 80 grit unless you were doing a lot of repair work.
Bruce

[WOODbTURNER]

Love mine too.
Smooth as running, no alox dust, no wearing of wheel like alox and diamond, coolish cut and touch, surface still clean like new and great finish to tools.
My blu max and pink alox wheels look out of place and unused now.
You won't regret getting one (imho) :)

[jefferson]

Bruce,

it appears to me that you are roughing a bowl with a spindle roughing gouge?

What's going on? Or have I misread the pics?

[bellyup]

Que?
Now Jeff, don't go all tech on me.
The roughing gouge was used to well.... rough.
The D-way spindle gouge was used for a final cut on the outside of the bowl. Beautiful bit of steel by the way .
Bruce

[issatree]

Hi Bruce,
That 180G. wheel seems to be the go.
My question is, I have a 13.5mm. Gun Barrel Drill, that I use constantly.
I drive it into End Grain at 3000 RPM. & don't have a Problem with it, but it does go Blunt now & then.

The other Chaps on The Forums, may also be able to answer this.

This Drill has a TCT end, & the only way I can sharpen it is by hand with a Ezy-lap Red Fine, Diam. Impr. Steel. It gets me by, but would one of these Wheels, sharpen this Drill ?

Personally, I think not, as normally one would use a Green Wheel, to sharpen TCT.
Its really not feasible to buy a Green Wheel, just to use on this Drill, every now & then.

[rsser]

A green wheel will cut TCT but not exactly put a fine edge on it. That's a different ballgame.

CBN is said to be optimal for high alloy steels.

TC isn't a steel.

[NeilS]

The roughing gouge was used to well.... rough.


One of the issues with spindle roughing gouges is that most have a very thin tang compared to the potentially large cutting area of the gouge. Apparently these thin tangs are not such an issue for spindle turning, although most of us have seen at least one with a bent or broken tang.

However, there are spindle roughing gouges and spindle roughing gouges. The P&N SRG and the Thompson SRG are in a separate category to most other SRGs. Both have substantial tangs that are milled from the billet stock; 1/2" diam in the case of the P&N (plus a substantial transition between the tang and flute), and 3/4" diam in the case of the Thompson. There may be other SRGs with similar substantial tangs that I am not aware of.

The other concern raised about using SRGs other than for spindle work is that because of their large cutting edge they can take a much larger bite than bowl gouges, which are typically much smaller in diameter. Not a recommended starting point for the novice, but more experienced bowl turners will anticipate the heavy duty forces involved in taking off a banana peel sized shaving and proceed accordingly (or not).

A very experienced bowl turner with one of the above more substantial SRGs might (not that I'm recommending it!!) rough down the outside of a bowl blank, BUT would not go anywhere near the inside of a bowl with it and never with that typical straight across grind. And, an experienced bowl turner would also realise that a longer handle than the one that came with the SRG was need to counteract the extra forces involved.

Now, I'm not much of a spindle turner, but I fail to see the difference (other than grain direction) between roughing down a spindle blank and the outside of a bowl blank of the same diameter. Yes, twice every rev you are cutting towards the endgrain on a bowl blank, but I can't see how a bowl gouge is any better than an SRG at handling this. Surely a 1" SRG will manage the task as well as a 1" bowl gouge.

[jefferson]

Que?
Now Jeff, don't go all tech on me.
The roughing gouge was used to well.... rough.
The D-way spindle gouge was used for a final cut on the outside of the bowl. Beautiful bit of steel by the way .
Bruce

I'm not trying to getting technical with you Bruce, but one of the first lessons I had included the edict that a spindle roughing gouge was not to be used on bowl work.

You face a major catch should the shoulder/s touch end grain at speed. Enough said.

[rsser]

Agree with Jeff and Neil.

Small bowl (which the Gidgee prob was given the species) you can with care get away with a SPG on the outside but that use is in general 'bowel' gouge territory ;-}

[NeilS]

....normally one would use a Green Wheel, to sharpen TCT.




A green wheel will cut TCT but not exactly put a fine edge on it. That's a different ballgame.

CBN is said to be optimal for high alloy steels.

TC isn't a steel.

Diamond is said to be best for TCT.

CBN is said to be best for steels.

CBN wheels will cut carbide and diamond wheels will cut steel, they just don't do it as well.

If your main use for the wheel is grinding HSS, get a CBN wheel. Occasional use for TCT is OK.

If your main use of the wheel is for grinding TCT, get a diamond wheel.

[NeilS]

.... one of the first lessons I had included the edict that a spindle roughing gouge was not to be used on bowl work.



And rightly so, Jeff. Any responsible teacher should warn the novice of the almost inevitable consequences of doing so. But, Bruce is no longer a novice. He just (temporarily) forgot that there are others on the forum who will be...:D

[bellyup]

Hang on guys!
I think you are assuming I have a lovely 200mm round Gidgee blank, perfect and concentric , ready to go - NAH!!
I had an ugly size lump of Gidgee( 300mm) that I trimmed on the Bastardo 4 with a 20mm/ 1.2 tpi bi-metal blade - at best it was an octagon - at best!!
The P&N 20mm roughing gouge (love the thing) worked its wonder and turned it into round. From there the "normal "bowl gouges were used to hollow and form . When I was happy with the final outside shape I used the D-way 20mm spindle gouge to perfect the last cut before sanding.
Call me obtuse .....but is there anything wrong with the above? Am I missing something?
:?
Bruce
P.S. this is about a new grinding wheel purchase........maybe you need to look at an new OH&S thread for newbs to address the concerns you raise.

[bellyup]

Neil,
Thanks for the pencil idea - tried it today and the thing is perfectly true - maybe the resonance is set up in the tool and not the wheel? On a scale of 1 - 10, the vibration is a 1 - to date , very happy with the wheel. Can't wait to sharpen my "SRG" again, :D
Bruce.

[robo hippy]

I got some matrix style CBN wheels maybe 6 years ago at a cost of about $300 each. They are similar to the diamond wheels that Woodcraft sells, 1 inch aluminum hub/wheel with 3/16 inch of grinding matrix bonded to the wheel. They are about half way worn out. I now have the D Way wheels as well. I prefer the D Way wheels. The matrix style will develope some run out after heavy use, like any wheel will where the matrix wears away, a thousandth or two run out in the shaft, the bushing, the hub, the wheel, added to millions of revolutions will cause the wheel to get some run out. This is not some thing that can be fixed at home, and they will eat a diamond dresser. You have to get them back to the manufacturer.

My D Way tools wheels have broken in a little. They do remove a lot of steel very quickly. I would say that the 80 grit cuts faster then the 30 grit wheels that came on my Baldor Grinder (heavy duty, top of the line machine made in the US, that I can abuse to the maximum and it doesn't slow down a bit). The 180 grit wheel is comparable to about 120 grit. The finish was a bit coarser when I first got them, than they are now. The bevel edge looks more polished. I consider them to be what every turner will want to have. You never need to balance them. You never need to true them up. You never need to clean them. There is no risk that they will ever blow up. They will last a life time for most turners. You can remove the wheel covers, at least on the outside, with no worries. The ringing that you get is natural harmonics, kind of like the noise differences between a cast iron lathe, and a steel tube lathe. I have gotten used to it.

No affiliation with D Way tools other than a very happy customer.

robo hippy

[turnerted]

Bellyup
How much did the freight work out on this wheel ? I thought about buying one of these a while ago but I thought the weight of it would make the freight too expensive .
Ted

[RETIRED]

Mine just arrived.

Cost of wheel $204.77

Freight $47.25.

Ordered on 1/10.

[bellyup]

Yep, As says - (mind you - you'd pay $20 p&h in Aust.) but for the postage cost you can also include some of his very nice chisels, the 1/2" spindle gouge is a new fav.
I think the CBN is fantastic (compared to where I was)
, your thoughts on the wheel?
Bruce.

[turnerted]

Thanks Bellyup and . I bought some of his beading tools back when the $A was $US 1.05 . From memory the freight then was about $25 and the weight was only about 500gm . I'll see how high the Ausie dollar goes this time .
Ted

[RETIRED]

, your thoughts on the wheel?
Bruce.I have been using it all day and very impressed.

Better than my alox wheels. Doesn't need dressing every 2 hours.

Leaves a bloody good edge.

What more could a turner want? mmmmm

[Jim Carroll]

What more could a turner want? mmmmm

2 off them :2tsup:

[RETIRED]

2 off them :2tsup:Ordered another one.:-

[NeilS]

I've promised myself a second one when/if the Oz$ gets to US$1.20.....:rolleyes:

[bellyup]

Just had a note fromDave at D-way tools - he can ship 2 wheels in one post box for the same price. Might help with costs if 2 people get together.
Bruce.

[robo hippy]

US Postal service has flat rate shipping boxes, which is pretty cheap. I know there is a 20 pound weight limit on out of country shipping.

robo hippy

[turnerted]

I could be interested in sharing freight costs if there is someone living near me who wants one . No point in having to reship though . PM me if interested with your phone number and we can talk .
Ted