Moving away from waterstones

[tnimble]

The diamonds can get loose from the carrier. This happens most likely when grinding softer metals and at high angles. Also be careful when using small width items on the DMT I reckon.

 

[Paul Chapman]

I've used my DMT stones for many years without any problems. As Rob says, they start off feeling very rough and cut quite aggressively but quickly settle down. It's possible that they have now lost this initial roughness and that's made you think the diamonds have fallen out.

If the diamonds have fallen out, I'm sure Trend would want to know about it and would replace the stone.

Cheers :wink:

Paul

 

[Karl]

Hi Vormulac

I bought the Trend double sided stone. Like Rob says, it cuts too coarsely to start off with, but soon beds in. Mine did so after the first couple of days, but i'd consider myself a heavy user - every day, at least a couple of times a day (sometimes significantly more). So yours is still cutting, then there's nowt up with it. If not, then get onto Trend.

I've had mine for a couple of weeks now and think it's great especially for taking out on site (which was the main reason I wanted to get away from waterstones).

Just need to get a good polishing stone now (for shop use only).

Cheers

Karl

 

[paulm]

Hi Vormulac
Just need to get a good polishing stone now (for shop use only).
Karl

Can recommend the Spyderco superfine ceramic stone Karl, as mentioned by Newt and Woodbloke etc in other threads.

Gives a great mirror polish and suprisingly quickly. Only thing is to be prepared to spend a half hour or so flattening it with a coarse diamond stone if you're a bit fussy like me :roll: , but once done it doesn't look like it will wear much at all so pretty much a one-off job.

Cheers, Paul

 

[Vormulac]

I haven't touched that Trend stone in over a year, but I seem to recall it stopped cutting all together, my emails to the company I bought it from at the show went unanswered. I'll dig it out and have another look though.
It's good to see so many of you guys extolling the virtues of DMT stones, perhaps I'll start saving my pennies (this could take a while, the birth of Number 2 son last month has left me somewhat skint!).

 

[Paul Chapman]

I seem to recall it stopped cutting all together, my emails to the company I bought it from at the show went unanswered.

If it really is that bad and has stopped cutting altogether, why not PM andy@trend who's a member of the forum. The Trend stones should perform as well as the DMTs and I'm sure Trend would do something about it.

Cheers :wink:

Paul

 

[Vormulac]

That's good advice, thanks Paul. I'll certainly dig it out this weekend and have a good thorough look at it.

 

[lwilliams]

...I am getting somewhat fed up with the mess and constant flattening required on the stones, and was considering switching to another method. ...
Ideally I would like to stick to two stones...
Any other suggestions?

I used to spend more time flattening my water stones than sharpening and, I too, hated the mess and space required.

I've gone back to oil stones. I use a medium India and a translucent hard Arkansas. Both need to be kept flat and fast cutting by dressing and I use a DMT coarse diamond stone for that. Oil stones don't wear out of flat nearly as quickly as water stones but they do go out of flat. I strop after honing with chromium oxide or a product called 'Yellow Stone."

I also use a coarse India when flattening new tools and it also needs to be kept flat and dressed. You'll find yourself dressing your oil stones more to refresh the cutting surface than to flatten the stone but it makes sharpening a lot easier if your stones have the same flat topography. Oil stones, when kept dressed, cut nearly as quickly as water stones.

I use WD-40 for honing oil because it's convenient and always around. My sharpening area is always set up and ready to go. Just a wipe with a rag is all it takes to clean up after honing. My honing system takes up less than two square feet.

You're not going to end up with a mirror finish because the hard Arkansas is about a 1000 grit stone. I don't think you'll miss polishing a mirror surface but I think you'll enjoy the quick sharp edges you'll be able to get.

 

[bugbear]

You're not going to end up with a mirror finish because the hard Arkansas is about a 1000 grit stone. I don't think you'll miss polishing a mirror surface but I think you'll enjoy the quick sharp edges you'll be able to get.

I'm not sure that's correct; I know that this (famous) table claims it:

http://users.ameritech.net/knives/grits.htm

But it's talking about particle sizes.

Now, cutting action (and effect) is determined by factors in addition to particle size.

Here's speed:

http://users.ameritech.net/knives/speed.htm

I don't know of one for edge quality

BugBear

 

[Philly]

Welcome to the forum, Larry!
Good to have you aboard,
Philly

 

[lwilliams]

Thanks, Philly.

Bugbear,

Either that chart showing cutting speeds of different abrasives is wrong or I'm doing something wrong. They show diamonds as being the fastest cutting and I find them among the slowest cutting of abrasives. I've tried pastes on iron, aluminum, and polycarbonate. I've also tried mounted stones and diamond grinding wheels for the oscillating diamond grinder we use in our metal shop. My experience is that aluminum oxide and silicon carbide abrasives of similar grits cut significantly faster.

The technical representative of the company that makes the diamond wheels for our grinder told me electroplated diamond abrasives shouldn't be used on steel. He said the stringy swarf from grinding steel will quickly abrade away the nickel matrix the diamonds are mounted in. These abrasives are intended to be used on materials that produce a granular swarf like stone or carbide. I only use diamond honing stones to maintain my oil stones but never on common tool steels now.

The only advantage of diamonds I know if is that they'll cut almost anything. I believe their faceted round shape naturally makes them slow cutting.

 

[tnimble]

That is exactly my experience lwilliams. The only difference why diamond paste do a faster job on flattening 'large' surfaces is they do not wear down as fast as SiC and AlO.

The same seems to be for the rest of the graph also. Water stones are depicted as the seconds fastest. The only difference between AlO abrasive and a waterstone is the backer material. Paper, plastic, linnen versus a ceramic matrrix. The cutting speed of AlO is the same or faster than a waterstone. Again the difference is when the AlO wears down on a waterstone its replaced with fresh AlO particles. With a sand paper tpye abrasive a worn down particle is not replaced.

The same for ceramic stones. Syntactic water stones are ceramic stones. The difference is the hardness and make up of the ceramic.

I use diamond stones (I own two) mainly for flattening my other stones. They are also handy for a real quick touch up when you have no water at hand or for very norrow tools.

DMT diamond stones are diamonds embeded on a nickel plated thin plate of steel. Ezelap stones seems to be the same but this is a bit hard to say for sure.

 

[bugbear]

The technical representative of the company that makes the diamond wheels for our grinder told me electroplated diamond abrasives shouldn't be used on steel.

That's "interesting" (*)

BugBear

(*) monumental British understatement, obviously!!

 

[Jake]

It's a bit of a different application at 3/4000 rpm, surely?

 

[bugbear]

It's a bit of a different application at 3/4000 rpm, surely?

Owner of DMT plates will be hoping so - fair comment.

BugBear

 

[lwilliams]

It's a bit of a different application at 3/4000 rpm, surely?

Diamond grinders run pretty slow because heat is a real problem with diamonds. They're pure carbon, like coal. If you get them hot, they burn. I don't have the manual for our grinder handy but it runs somewhere around 600 rpm.