What causes scratches when using the platform jig ?

[RichColvin]

I made a 2d platform jig using a plastic cutting board, and the knives I sharpened on it also get scratches half way up the side.  I've read how others have the same problem.  Anyone know what causes this, and how to prevent it ?

Rich

[cbwx34]

I made a 2d platform jig using a plastic cutting board, and the knives I sharpened on it also get scratches half way up the side.  I've read how others have the same problem.  Anyone know what causes this, and how to prevent it ?

Rich

I've used it before... IME, plastic cutting board can be one of the "most scratchiest" things you can use.  I had pretty good luck covering it with a smooth duct tape (as long as it didn't get contaminated).  Might give that (or any smooth tape?) a try.

[Y-Not]

I suspect that the scratches are caused by tiny bits of stone and metal getting trapped between the blade and the platform.
Last week I made one of Herman's knife rest platforms.
I've got about a dozen or so disposable knives that I'm using to learn with.
The platform I used was just metal. Not coated/covered with anything and I got the expected scratches.  Again, on my disposable knives. It was expected and no real harm done.

I've since coated it with 3 coats of plastic coating.
A drop of mineral oil on the platform rubbed into the now coated surface and one drop on each side of the knife to be sharpened and it's SUPER slick.
I completely colored both sides of 6 different knives and went to sharpening...Thus far, not a scratch to be seen.

In the attached, the platform looks to be uneven. It's not. It's just the funky angle of the photo.

So far, this seems to be the solution to several knife sharpening issues I've been having.

[RichColvin]

Tony,

That is an AWESOME idea !   I'll try that on a knife soon.

Kind regards,
Rich

[Dutchman]

...
I've since coated it with 3 coats of plastic coating.
A drop of mineral oil on the platform rubbed into the now coated surface and one drop on each side of the knife to be sharpened and it's SUPER slick.
...

How to coat it, with what? Tape? Spray? Paint?

[Y-Not]

How to coat it, with what? Tape? Spray? Paint?

Sorry...That bit might have been useful.

I used clear Plasti Dip.
It's much like the stuff you might find on the handles of pliers and the like.
Soft rubber like material.

https://plastidip.com/our-products/plasti-dip/

It comes in a spray can as well as a brush on type application.
I had a can of the spray sitting around so I thought it'd be worth trying.

[RickKrung]

I found some Plasti Dip (black, only can they had) at the local NAPA auto parts store.  The other two in town did not have any. 

(Actually, "in town" is the largest community in my county, Baker City, Oregon, and is one hour from the very small town I live in, Halfway, OR). 

Have not tried it yet.  Have some drill bit sharpening to do first.

Rick

[Y-Not]

I found some Plasti Dip (black, only can they had) at the local NAPA auto parts store.  The other two in town did not have any. 

(Actually, "in town" is the largest community in my county, Baker City, Oregon, and is one hour from the very small town I live in, Halfway, OR). 

Have not tried it yet.  Have some drill bit sharpening to do first.

Rick

So far I've done almost 20 knives and it's still holding up well.
One thing to keep in mind is to make sure that the surface is clean and ruff it up a bit so that the Plasti Dip has something to grip onto.

I finally grew a pair and brought out my kitchen knives.
I started with a Cutco knife that's been sheathed and sitting in the draw for 10+ years (not a Cutco fan) and it turned out perfectly.

I then took my least favorite Shun pairing knife and re-profiled due to a special request from my number one client (wife).  She hated the way the blade was shaped. Once I was done I gave it back to her and she's a no BS type person. In her words, you can't even tell that it's been altered. It looks like it came from the factory this way.

Big confidence booster there!

Then...I took out my 8 inch Shun.
It's my go to for most everything knife.

It took just one pass on the fine grade of the stone to get a burr. But it too turned out beautifully! 

I'll add some photos tomorrow.  Gotta go to bed now.

[Ken S]

We may know more when the new diamond wheels and ACC (Anti Corrosion Compound) are available this summer. Unlike traditional grinding wheels, with diamond wheels the only grinding debris is steel from the blade. This steel debris should be caught by the magnet in the water trough.

Another positive factor with the diamond wheels is that they must be used with a much lighter grinding pressure throughout the sharpening process. (This may be a good lesson for all grinding wheels.)

Until the summer:  I like the plastidip idea. Given a choice of colors, I would lean toward a color which would make any grindings more visible.

Before magnets were built into or attached to water troughs, we had frequent forum traffic about affixing magnets to water troughs. Like most of us back then, I attached a disk shaped magnet to my older model T7 trough with black electrical tape. Later, I upgraded to the AWT and eventually retaped the magnet to my T4 trough. (When Tormek redesigned the T3 to the T4, they did an almost complete job. The trough should have been redesigned to incorporate a magnet. I suspect price point engineering carried the day, leaving it to the user to add his own magnet.)

My point is that a magnet is essential to remove the steel particles.

Fastidious cleaning of the trough water will help. It is essential to change the water after truing the wheel. Bring out the turkey baster; remove most of the water; and wipe out the debris with a paper towel.

These suggestions will not eliminate scratching, however, they will move us closer to a scratch free environment.

Ken

[cbwx34]

So far I've done almost 20 knives and it's still holding up well.
One thing to keep in mind is to make sure that the surface is clean and ruff it up a bit so that the Plasti Dip has something to grip onto.

I finally grew a pair and brought out my kitchen knives.
I started with a Cutco knife that's been sheathed and sitting in the draw for 10+ years (not a Cutco fan) and it turned out perfectly.

I then took my least favorite Shun pairing knife and re-profiled due to a special request from my number one client (wife).  She hated the way the blade was shaped. Once I was done I gave it back to her and she's a no BS type person. In her words, you can't even tell that it's been altered. It looks like it came from the factory this way.

Big confidence booster there!

Then...I took out my 8 inch Shun.
It's my go to for most everything knife.

It took just one pass on the fine grade of the stone to get a burr. But it too turned out beautifully! 

I'll add some photos tomorrow.  Gotta go to bed now.

Glad to read it's working out.  Looking forward to the pics.

Thanks for sharing your "Tormek sharpening" journey, btw.  Very informative.

You may be the first person (that I'm aware of anyway) to use the "Homemade Knife Rest" in a commercial sharpening environment?  Maybe you can shoot some video when you get comfortable with it.

[Ken S]

I second CB's thoughts.

Ken

[Herman Trivilino]

I have found that the inexpensive adhesive-backed felt found in craft stores works well to prevent scratching. The mineral oil sounds like a dandy idea, too.

One member here reported no issues with scratching, and I guess that's due to him applying much less force to the platform. Use the platform as a guide to help you keep the blade at the right angle, but apply most of the force to the grindstone, very little force to the platform.

Note that the user manual discusses the fact that Tormek jigs are designed in such a way that when grinding edge tools, most of the force is applied to the grindstone, touted as a major advantage of the Tormek system. This may be the reason why the only Tormek platform jig is designed for edge angles that are far too blunt for knives.