PDA

View Full Version : Cheap Diamond Honing plate VS Expensive



Paul39
10th February 2013, 11:36 AM
When I ordered a spindle adapter for my lathe from PSI the minimum shipping was such that I added a diamond plate:

Diamond Impregnated Sharpening Plate at Penn State Industries (http://www.pennstateind.com/store/DIAMOND26.html)

Has anyone here tried a cheap Chinese one and also a more expensive one? Any observations?

I use the plate for my accursed skews. A quick swipe or two with any of them makes a difference in clean smooth cutting.

It is called a 400 grit, but with use it is not so grainy but still hones nicely.

I have been using it dry, a woodworker friend thought they should be wetted with water.

Any thoughts about that?

Edit: I noticed at the bottom of the page some references to diamond sharpening plates. I read that and dipped into the sharpening section and got educated.

I thought turners were opinionated, nothing like those seeking the sharpening grail.:D:D

dr4g0nfly
11th February 2013, 01:16 AM
I've no idea what you mean by 'cheap Chinese ones' - I keep a set of 3 from Aldi in my smock back pocket, 150, 400 & 600 grit. Never worn one out yet.

The only difference I can see is expensive ones come on a thicker sub-strait (metal plate), whereas the Aldi type are quite thin metal, mounted on a plastic backing. Are they any better or worse - eh, correct me if I'm wrong here but a Diamond is a Diamond (albeit an industrial diamond).

As you say a quick wipe over and the skew edge is refreshed. As is the scraper or even a spindle gouge.

I agree they seem to work a little better when wet, so a finger dabbed on the grinder quenching pot or even a quick (sorry ladies) spit and away I go.

Robson Valley
11th February 2013, 02:29 PM
The water is only the vehicle to wash away the swarf as it does with water stones, as oil does with oil stones. I can imagine that it might be useful to rinse once in a while. Try a squirt bottle.

See, the deal is that the diamond plates simply last longer = they are no better or worse than anything else. Given the hardness (duh!), the plates inherently last longer than the equivalent stones and they stay flat. The abrasive does not crush like the metallic oxides do. Now, if you need those things to float your boat, fine. I don't need those attributes.

To call the vehicles "lubricants' is bass-akwards to the entire process. We are talking abrasives here. When I need to use stones with wood carving tools, I FLOOD them with vehicle. A bit messy, but my entire goal and point is to regenerate the tool. I want a "carving sharp" edge on my tools. As such, that edge doesn't last more than 30 minutes of steady work. ... . .maybe I'm too fussy but that's what I enjoy.

FenceFurniture
11th February 2013, 02:42 PM
Two issues with diamond plates:
how flat they are
and whether the diamonds are electro-bonded to the top of the plate(inferior and cheaper) or sintered which means the diamonds are more impregnated into the substrate with pressure (and heat?), and have much greater longevity (but significantly more expensive in the short term).

Electro-bonded plates should be treated VERY carefully with low pressure applied, otherwise you'll wear them out in a week, as I did with my two DMTs (and I thought I was being gentle enough). Sintered plates are much tougher, and represent better long term value IMO.

Cheers
Brett

pommyphil
11th February 2013, 03:27 PM
I notice Aldi has a " special ". Four 150mm X 50mm diamond 200# to 600# on a block.

may not be sintered, but for $9.99 ........well

FenceFurniture
11th February 2013, 03:30 PM
Definitely not Phil, and could be useful (for something anyway). I'd be concerned about flatness, not the short lifespan (you get what you pay for).

Robson Valley
11th February 2013, 04:17 PM
Are those plates monocrystalline or polycrystalline diamond?
How much of a departure from optically flat will the plates need to be before anyone notices?

FenceFurniture
11th February 2013, 04:25 PM
Ah yes, another good point RV. If they don't specify then they are most likely Poly, which again is inferior and cheaper to produce, and less lasting.

Paul39
12th February 2013, 04:21 AM
Many thanks to all of the contributors above.

In another thread I saw where one could buy diamond honing paste for a most reasonable price.

When I have worn the diamond grit off my $15 plate I will get a lifetime supply of grit for less.

I, and probably most turners do not usually need a tool sharpened on a 12000 grit stone to poke into a piece of abrasive timber turning at 1400 rpm.

That fine edge will be gone in 1.37 second.

FenceFurniture
12th February 2013, 08:45 AM
Paul, I had vindication of Diamond Paste on Saturday - we had a couple of dozen members here for a GTG, and there were a couple of comments on the sharpness of my chisels (paste honed on MDF).

jimbur
18th February 2013, 02:10 PM
That fine edge will be gone in 1.37 second.

Aren't you being a bit optimistic Paul? I would suggest 1.365 seconds. :D

dr4g0nfly
18th February 2013, 11:22 PM
Aren't you being a bit optimistic Paul? I would suggest 1.365 seconds. :DAh, but that would be on your ultra hard Aus woods, I reckon I can get nearly 2 seconds on my English Oak!

Trent The Thief
19th February 2013, 10:33 PM
When I ordered a spindle adapter for my lathe from PSI the minimum shipping was such that I added a diamond plate:

Diamond Impregnated Sharpening Plate at Penn State Industries (http://www.pennstateind.com/store/DIAMOND26.html)

Has anyone here tried a cheap Chinese one and also a more expensive one? Any observations?

I use the plate for my accursed skews. A quick swipe or two with any of them makes a difference in clean smooth cutting.

It is called a 400 grit, but with use it is not so grainy but still hones nicely.

I have been using it dry, a woodworker friend thought they should be wetted with water.

Any thoughts about that?

Edit: I noticed at the bottom of the page some references to diamond sharpening plates. I read that and dipped into the sharpening section and got educated.

I thought turners were opinionated, nothing like those seeking the sharpening grail.:D:D


IMHO, use mineral oil or a NON-petroleum honing oil (check a knife shop). All I use are the cheap diamond plates. I'm happy with the results I've gotten. I mostly use them to touch up flats on carbide tools and to hone my spindlemaster clones.

rsser
28th February 2013, 11:58 AM
Just watch out for the quality of diamond paste too. The stuff I got via ebay must've just been waved over the seller's missus' engagement ring :rolleyes: