Thread: Experiment with diamond paste honing

Just as a flat to support very fine W&D sandpapers, I've been using a stone countertop cutout.
They polish the top surface then cut the hole(s) for the sink. The undersides are sort of a matte finish
and some of the stuff (snow white) was fake* but as heavy as the granite. I got into a business that made those,
they must have had 40 pallets in the stone yard with 20-30 cutouts on each.
"Take what you like but don't mess up the piles."
I took a dozen: white & gray & cream colored, speckled granite, nearly black, marbled.
The quality of the light reflections suggests that the polished surface is quite flat.
* Easy to tell. Flip it over: "Made In Germany".

Otherwise, I bought a couple of beautiful Italian pink & gray 300x300x12 mm polished marble tiles
to use as hot pot placemats on the table.

Ben, MDF will certainly get you going so you can assess what you think of the various pastes for producing edges. It makes for very cheap entry - $15 per 5ml syringe plus postage from Ballina and a couple of MDF offcuts.

If you like the edge it produces with the minimal setup/down procedure then you can think about acquiring some proper metal blocks.

Any thoughts on aluminium as stropping blocks with diamond paste fence furniture?

Originally Posted by Ben Dono

Any thoughts on aluminium as stropping blocks with diamond paste fence furniture?

Not sure Ben. Quite obviously softer than Cast iron, but harder than MDF - 'cept the MDF can just be easily replaced when no longer flat.

Mind you even CI or mild steel will eventually have a dish, and alum should be easier to flatten (using sand paper on glass/granite etc). For using a metal file on alum (or brass) the trick is fill the file with chalk to stop the clogging, but that's probably not applicable with sandpaper.

Enough of the caveats! Try it and see......

Hi Ben

The essential and critical element for using diamond paste effectively is that the grit in the paste must bed into a medium, and that this medium holds the grit securely. Wood does not do this - the grit gets pushed below the surface and then stops cutting. Glass and other hard/non-porous materials do not do this - the paste lies on the surface and the lapping action wear this into a hollow. Steel is generally too hard - although Lee Valley (and Carba-tec) sell a mild steel plate that works pretty well (I tested these for LV).

I made my own cast iron plates some years ago. This cost a minimal amount as I used old, broken cast iron handplanes (Stanley). The tutorial is below ...

http://www.inthewoodshop.com/Woodwor...mondpaste.html

Regards from Perth

Derek

Originally Posted by derekcohen

.....and that this medium holds the grit securely. Wood does not do this - the grit gets pushed below the surface and then stops cutting.

Yes, and with MDF the consumption of the paste is significantly higher because of this (assuming that you are classifying MDF as wood for these purposes Derek, although it's more akin to dense cardboard ).

I started with MDF, which worked well enough to allow me to tell that the paste works very well, and noticed a drop in the amount of paste required when I switched to CI blocks.

So, Ben, first things first, and you need to assess whether or not you like working with paste. I would recommend trying it with some MDF first before you invest either time and effort or money on Alum or using old planes etc. That will be the cheapest and easiest way to assess it.

I was able to produce shavings like these from Spotted Gum (a shocker for tear out previously) after using paste on MDF. These shavings had been manhandled quite a bit during the course of the photograph. I remember writing at the time (couple of years ago) that the shaving shot up out of the plane uncurled and produced a shout of laughter at the result (I was shocked/startled):

What size cast iron plate are you looking for (all three dimensions and min/max limits)?
I have quite a few cast iron pieces and would be happy to pass one on to you. I'll even grind it flat on both sides for you on my surface grinder. You pay postage or we find another way of getting it to you.
Feel free to PM me.

Interesting discussion going on here. Any thoughts on the suitability of using Laminex / Formica faced MDF as a base?
It would be easily sourced from a kitchen builder from the offcuts bin, or an old kitchen from a renovation job, and should be harder than plain MDF. Another thought was to try some Masonite, again on a thick MDF backing, especially if you can find the tempered variety.

I intend using some 6mm glass backed up on MDF as an experiment, and I haven't got a ready source of cast iron flat plate these days.

Lovely shavings you are getting there Brett, something I am trying to emulate.

Alan...

I'm a big MDF fan, I went to the trouble to get an old plane iron and flatten it and set it up to use diamond paste and did not like the results so in the bin it went. I'm sticking to MDF for now.

SB

Here are shavings ...



Regards from Perth

Derek

Originally Posted by Uncle Al

Interesting discussion going on here. Any thoughts on the suitability of using Laminex / Formica faced MDF as a base?

Similar to using glass Uncle - not desirable because the diamonds can't embed properly, so they really just roll around in the paste. You could always flip it over and use the MDF side though.

I haven't looked at that particular vid Derek, but have seen previous ones - the shavings those guys produce are just crackers (prolly using paste on CI blocks ).

Joe, that's mighty generous of you!

You just made my day...and it's only 5:30am!

Thank you!

Will shoot off a PM today.

Well since I posed the question I should be the one to do the comparison tests!

When I get the chance (should be a looong while yet...busy with the farm and a young lad!) I will test out aluminium vs CI with diamond honing pastes.

It's pretty obvious that the aluminium won't be as durable or stable as the CI but it's much easier to come buy and most of the flattening can be done by fly cutting it on the mill.

I suspect with the aluminium it will be a stropping action only...but will test it both ways.

I will also test some smaller un machined anodised sections (they tend to be flatter when smaller) to see if their is any benefits.

I have never looked into the heat treatment properties or work hardening of Ally but will try and assess that as well.

From memory, the veritas profiled honing plate for their v grove and beading plane was hard anodised. Maybe that was functional or it could have been just for looks?

Haven't received any PM from you yet, Ben.
You kindled my interest though: I'm going to make two plates when I hear from you, one for me and one for you.
I've decided to do one side with a grid pattern of narrow grooves (on the shaper just before grinding), like expensive lappi9ng plates have, and the other side plain flat.
I suspect that the grooved side will work better for bigger grits and allow lubricant more easily, but I don't really know.

The other comment I wanted to make is that I use a cast iron disk on a motor to hone my TC metal scraper tips. These get the diamond grit embedded using a small ball race/bearing on a handle to push the diamond grit onto the spinning CI disk. That seems to work very well. Maybe embedding the diamond into a stationary plate by moving the bearing back and forth might work too.
I have also used an aluminium disk for honing the TC scrapers. That worked just as well, but you had to go very gently. It was easy to dig the tool into the aluminium and take a shaving off - diamonds and all! That is pretty difficult to do on CI.

Now I'm away for a fortnight from Wednesday. I'll get onto the plates on my return.