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Thanks for the detailed reply Nick, its appreciated.

I will look at the video.

Many thanks

Pete

Hopefully someone can answer this. Not sure why but I got what I call a 'smiley' on a couple of blades yesterday.
By that I mean the grind was OK until the last section where the belly started to curve, then it widened and narrowed towards the tip. My fail as was tired and should have called it a day but we live and learn I guess.

So my thoughts are that I might have 'swept' the blades too much on the last portion on the grind possibly as opposed to keeping the edge square to the wheel , well if that make sense?

Thanks in advance

Just noticed additional replies ...many thanks everyone , I will have a look at them all.

I bought mine for Wood Turners Wonders and was told to use a wire brush, which to be fair worked.

Then again with fallout spray you don't really need to use anything except a tooth brush I suppose as the spray dissolves the micro steel particles as it does on car paint.

If there is a bend in a knife or bow then it likely got there when it was heat treated.

If could have been stacked with other knives and so heat differentials when quenched or it might not have been normalised before the heat treat and so stresses in the steel or a bad quench...many reasons in fact .

Now if it has been hardened as per specs then basically it will now be a spring with memory, so the bow will in stay in the spine. If you try to straighten then it is highly likely to snap and when they do it can send steel flying.

Yes I have straightened knives but they have been mass produced factory knives which are poor steel (lots about form top knife making companies!) and they will have been heat treated to a really low spec so they will sharpen easier....

Having had issues with my CBN wheels taking longer to cut I learnt the other day they need cleaning and scrubbing....

So I tried the normally methods such as paraffin, wire brushing etc but was not too impressed.

I then realised I had just bought some 'fallout spray' for my car alloys / paintwork. This stuff is based on Oxalic acid and it is designed to react with tiny steel particles such as brake dust... ever seen those tiny rust spots on your car paint work and wondered what they were ?

https://www.cleanyourcar.co.uk/exterior/paint-contamination/iron-fallout


So I sprayed my CBN wheels with the fallout spray...WOW! and instant reaction, the fluid went from clear to purple as it was reacting with the steel particles and dissolving them. I then scrubbed them like hell with a steel brush and rinsed.

Result!...the 400 grit wheel looked far far better and few CBN could be seen. The 1000 grit wheel was better but still smooth, though this might be due to is being broken in as such, hence I need to do a sharpening on it and see if it cuts OK.

The other thing I did was put both wheel as section at a time in my ultrasonic tank...that also brought yet more crud out of the surface.

I expect this will also be fine on diamond wheels as remember it it does hurt car paint work you will be fine.....

Just wear rubber gloves as it pongs if you get it on your skin...

Ken ...please move if in the wrong section...

Cheers

Pete

The steels I use for my knife making are Elmax @ 60-61HRC, Vanax, AEB-L , 52100 and 26c3.

Steels like Elmax and Vanax which are third generation powder steel alloys are incredibly wear resistant. Elmax for example is used in the North Sea on oil pipe lines , food processing machines and high pressure injection moulding. They and other alloy tool steels without doubt are best sharpened on CBN wheels as they are designed NOT to wear. I contacted Vadim and he gave me loads of advice and I also bought his software / book on sharpening...both are excellent.

CBN also outperform diamond apparently due to how they break down in use.

AEB-L is not in the same league as the super steels and although it has a fine gain structure it is not a powder steel.  Yes its a great steel but if you grind out a hardened knife blank of AEB-L it feels totally different and feels 'softer' for want of a better term than Elmax. AEB-L is far easier to hand finish , Elmax and Vanax are punishing on the arms as they just don't wear easily when hand sanding.

Note I said hardened blanks as hardened blanks cut faster on ceramic belts. Basically 'hog out' 90% of your steel on 36 or 60 grit as those grits run cooler. Then the remainder of the bevel can be done on finer grits....but with all grits dip in cool water every pass, or as I do keep your thumb of the blade for rest assured your thumb will let you know how hot that steel is wayyy before it reaches its tempering temperature. In the case of the last batch of Elmax I had heat treated it was a 500c tempering cycle 

Now back to your original question, CBN wheels are they way to go for sure, I have a 600 and 1000 grit on my T8 and then it is onto paper honing wheels/diamond. I doubt the original stone will do anything where these high wear steels are concerned, also not sure about the diamond paste on the Tormek leather wheel and what effect it will have.

But even before CBN I grind all my blades down to just above .5mm on 2 x 72 inch ceramic belts, obviously cooling the blade every pass. Then that edge is bevelled at 17.5 degrees or lower. Only then do I go to the CBN wheels which sometimes takes 20 -30 mins to refine the edge to 1000 grit.  The final stage is paper honing wheels with diamond paste....both the CBN wheels and honing wheels use Vadim's software / homemade jig stands.

Brilliant ...thanks for this , will have a look now as my pal here soon with those knives  ...

Many thanks

Could anyone possibly give me some advice place on grinding Scandi grinds on a Tormek please as I have a pal over mine this eve with a box full of them!  ...he wants them doing this eve if time allows.

What I want to know is the best technique you guys have possibly figured for Scandi grinds, preferably a true Scandi grind with no micro bevel but I am not sure this is possible on a wheel..(normally I hand sharpen Scandi blades)

The knives are Mora's I think.

Any tips or video link most welcome , oh and I have a T8.

Much appreciated

Pete

Thanks guys I will have a look

EDIT. Whilst looking I see a few companies make the 'system' type tool storage boxes, which loo like I need to investigate further.

Having seen some fantastic work stations on here which Tormek machines sit on at a good working height and additionally have all the tools in the drawers below, I wanted to ask if anyone from the UK has bought such a unit online , if so from where please?

I have had a look over the past few days but I am not having much look so thought it best to ask as I am sure someone will have found something suitable.

The other thing I wanted to as is what are folk using for lining the draws of a unit when they buy for keeping all the attachments safe?
Are there insert available from Tormek or are folk using special foams and cutting it themselves, if so what type of foam.

Thanks in advance.

Pete

Thanks for posting, I shall be upgrading my old measuring jig after seeing this   

Thanks for letting me know...I will have another attempt.

Well I think I must have done something wrong on my first attempt at sharpening scissors as pretty bad vibrations when I tried sharpening. Should I use the supplied T8 stone?

Looking at previous posts I am wondering if it was because I used my CBN wheel?.....or because some of the modern scissor types are such hard steels?

Either way I quickly gave up.

Any thoughts welcome.

Cheers

EDIT.... I just saw the previous post to mine , so I suppose I have my answer 

Thanks for all your replies gents.