Grinding tools, should I make a jig

[28ten]

I have ground tools in the past, but with limited success, and for the last few years I have used indexable tools. Anyway I want to have a crack at grinding my tools again, is it worth me making simple angle jig to help? or should I just practice more?  I have seen the old boys doing it freehand and they tell me how simple it is but when I try I get something with about 6 different angles on 

[bogstandard]

Cynric, you have answered your own question.

when I try I get something with about 6 different angles on

Is it six jigs for all the individual angles, or one jig with all angles the same.

To be really honest, and I have said this before, it really is just a matter of getting down to it and playing about. The angles are not super crititical, and most angle grinding charts are for 'ideal' situations. 99% of the work we do couldn't really be classed as ideal.
It is easy for me to tell you how easy it should be, because I do it all the time without thinking about it, but I do understand your frustrations about getting it right.

Concentrate on one face at a time, get it right, then go to the next one.
I always grind side, front then top, if that is of any help.

If needs be, felt tip mark up the part you want to grind, with the angle you want, and grind away until one face is done, then grind the next face.

A few basic rules

Keep the tool cool when grinding.

Always keep your grinding wheels well dressed and with nice square faces.

Make sure you have rigid tool rests. If you have ones that wobble, you will get nice wobbly faces.

After you have finished grinding, hone the top face to give nice keen edges on top of the front and side faces. Don't use diamond for honing HSS, if you can, get an Arkansas stone for doing the job. Mine is about 30 years old and still doing a good job. If you can't get one, a fine emery stone with oil should be OK, or even a large chisel oilstone will do. Those edges have to be razor sharp for doing a good job.

John

[28ten]

Cynric, you have answered your own question.

when I try I get something with about 6 different angles on

Is it six jigs for all the individual angles, or one jig with all angles the same.

To be really honest, and I have said this before, it really is just a matter of getting down to it and playing about. The angles are not super crititical, and most angle grinding charts are for 'ideal' situations. 99% of the work we do couldn't really be classed as ideal.
It is easy for me to tell you how easy it should be, because I do it all the time without thinking about it, but I do understand your frustrations about getting it right.

Concentrate on one face at a time, get it right, then go to the next one.
I always grind side, front then top, if that is of any help.

If needs be, felt tip mark up the part you want to grind, with the angle you want, and grind away until one face is done, then grind the next face.

A few basic rules

Keep the tool cool when grinding.

Always keep your grinding wheels well dressed and with nice square faces.

Make sure you have rigid tool rests. If you have ones that wobble, you will get nice wobbly faces.

After you have finished grinding, hone the top face to give nice keen edges on top of the front and side faces. Don't use diamond for honing HSS, if you can, get an Arkansas stone for doing the job. Mine is about 30 years old and still doing a good job. If you can't get one, a fine emery stone with oil should be OK, or even a large chisel oilstone will do. Those edges have to be razor sharp for doing a good job.

John

I thought you might say it was practice!
I guess i'll just have to order a box of HSS toolsteel and get on with it  I can see me turning up at your door again    It might be worth my while making a new tool rest, maybe a new wheel as well, it was the brown you recommended wasn't it ?

[jim]

when i served my apprenticeship, you had to grind all your own tools, by hand.

it really is just practice

when i grind up tools and drills, i colour the end of the tool with marker pen, makes it much easier to see at a glance if its all ok

[bogstandard]

Cynric,

Both RDG and Arc do very good prices for HSS blanks.

I only use a brown wheel because I can, a normal fine grey grit will do just fine normally.

Dressing of the wheel is very important, and almost any of the latest diamond flat edged ones do a good job.

I personally use the multi point one here

http://www.arceurotrade.co.uk/Catalogue/Diamond-Tools/Diamond-Dressers

But they create loads of very abrasive dust, so cover everthing up well before dressing.


John

[John Stevenson]

That dresser that John linked to is bloody brilliant but buy just the head and make a shank or use a bolt.
That shank is more money than the dresser 

If you have a surface grinder these will stick on the sticky table and ensure you get a flat wheel, used freehand they don't dig in like a single point one and you finish up taking less of the wheel so longer life / less mess.

Brilliant for de-clawing next door cat............

John S.

[28ten]

Bogs,
that's the dresser I have been using, I managed to get the grinding wheel nice and square very quickly using it. I shall be ordering some tool blanks today.

[spuddevans]

Don't use diamond for honing HSS, if you can, get an Arkansas stone for doing the job.

Can I ask why Diamond is not recommended for honing Hss?

Tim

[bogstandard]

You can use diamond, but the crap that comes off HSS clogs the diamond plates up and makes them useless.
You will also find that diamond is very harsh when used on HSS, cutting minute grooves rather than the chisel like honed finish you should be trying to achieve with a fine oiled stone.

Bogs

[28ten]

You can use diamond, but the crap that comes off HSS clogs the diamond plates up and makes them useless.
You will also find that diamond is very harsh when used on HSS, cutting minute grooves rather than the chisel like honed finish you should be trying to achieve with a fine oiled stone.

Bogs

Thanks Bogs, thats handy to know. Hopefully I will get the grinder up and running this w/e. I'm going to make a new support.
Sorry to be dumb, but, how do you accurately measure the angles on the tool?

[spuddevans]

You can use diamond, but the crap that comes off HSS clogs the diamond plates up and makes them useless.
You will also find that diamond is very harsh when used on HSS, cutting minute grooves rather than the chisel like honed finish you should be trying to achieve with a fine oiled stone.

Bogs

Ahh, that makes sense. I've got a cheap diamond 4-sided "stone" that I use to hone at the moment, I got it not knowing that I wasnt totally suitable for Hss tools ( though I have resurrected a couple of carbide inserts with it ). I'll have to look out for an arkansas stone.


Thanks for explaining that 


Tim

[sbwhart]

Hi

Don't get too hung up about getting the angle spot on they are only guidelines as long as you get them going the correct way and don't have too sharp an angle as this will only weaken the tool:- aim for 3 deg but no more than 10.

In a jobbing shop they wouldn't worry to much about it as long as they got the job done:- but, In a manufacturing volume production environment, a lot of time and effort will be spent getting the tooling correct but that is only because they want to optimise output and efficiency

In a home workshop, find something that works for you and have fun.

Hope this helps

Have fun

Stew

[Darren]

I find if you use white spirit instead of water to lube/wash the diamond stone it doesn't clog up. In fact it will clean up a stone after it's been used dry.

Forget using WD40 with diamond, somehow it doesn't work as well as it does with a normal stone.

Diamond stones cut much harder/faster than their grit size would suggest. If you want a fine finish for tool grinding then use a fine diamond stone and you will have no problems.