Sharpening Chisels

[Munroast]

Up until recently I have had access to a powered wet stone sharpener - just brilliant, no matter how hard you press the chisel never gets hot.

It has now bee replaced with a belt sharpener, if I'm not super cautious it is easy to blue bits of the chisel. we only seem to have a 120grit belt. would a 60g belt help keep the temperature down when removing a lot of metal (and then just use the 120g for the last bit)

Any other thoughts on using a belt sharpener ? (would love the wet stone back)
https://www.google.com/search?q=rob...9YfOWJcyBhbIPnuSJqAo&oq=robert+sorby+pro+edge
far from impressed

 

[big-all]

no much finer not coarser
how are you honing them[the 5% angle change at the tip] ??
once the bevel is correct you never need to bevel just hone unless the tip is damaged

 

[Burnerman]

60 grit is very rough and only use it to remove notches etc then finish with a finer grit than 120 if you can get it.
I dip my chisels into water frequently but of course you have to reposition the thing every time.
I finish on a traditional oil stone, estimating the final angle when the oil film squeezes out ahead of the chisel.....that's around 5 deg.
John

 

[Munroast]

25° then 30 at the tip

was wondering if 60 g would have less heat build up when taking a damaged edge back to the full 25° then use the 120 to finish the 25 degree and then form the 30.
I always finish off on a traditional wet stone

and yes I have been dipping the chisle into cold water, but I am finding heat build up is very rapid, as little as 5 seconds can cause a touch of blueing to the ti when trying to get the whole 25° edge formed.


My question still remains, when forming the whole 25 degree bevel - would 60g generate more heat than 120g ?

 

[big-all]

the heat is because off friction coarser the material the better the grip greater the friction
thats why the stone turns far slower is run through water and is very very fine to reduce friction
in other words it will heat hup perhaps 3 times faster on a 60 grit

 

[Munroast]

but with 120 grit you are removing bigger pieces of metal (twice the size) so is there not less friction, I know it sounds counter intuitive but I'm thinking the opposite and the finer the grit the greater the friction.

 

[Trazor]

Go as fine as possible, and keep dipping the blade into water, every few seconds.

 

[big-all]

60 is far courser 120 is finer 240 is even finer ect

random link
https://duckduckgo.com/?t=ffsb&q=sa...f/images/imagemanager/abrasive_grit_sizes.jpg

 

[Munroast]

60 is far courser 120 is finer 240 is even finer ect

random link
https://duckduckgo.com/?t=ffsb&q=sanding+paper+grit+size&atb=v227-1&iax=images&ia=images&iai=http://www.baileypaints.co.uk/uf/00151_8bd95c42a43f/images/imagemanager/abrasive_grit_sizes.jpg

i do know the way grading works for abrasives, if you had read my earlier post the you would have understood that!

 

[Justin Passing]

Get some waterproof sanding belts!!
Doesn't need a vast amount of water to make a difference. I've found a 1" cheap paint brush ok to apply water to the blade - you soon see if it's boiling.
It would depend of course where the motor is - I'm assuming it's off to one side and not inside the belt as on a portable where it might get wet though I have done that on site.

Having said that I use wet sharpeners...
I use shallower angles for softwood so have sets of Jap chisels at different angles.
All are polished to a high shine on the back as are plane blades.
A 60½A gets its second bevel underneath to keep the top angle low.

Sharpening isn't quite the same as friction I don't think. Swarf off a lathe is bloody hot because of the work you're putting in, not from friction I reckon.

 

[big-all]

shallower the angle the sharper the chisel but easier it blunts or chips

 

[Munroast]

Get some waterproof sanding belts!!
Doesn't need a vast amount of water to make a difference. I've found a 1" cheap paint brush ok to apply water to the blade - you soon see if it's boiling.
It would depend of course where the motor is - I'm assuming it's off to one side and not inside the belt as on a portable where it might get wet though I have done that on site.

Having said that I use wet sharpeners...
I use shallower angles for softwood so have sets of Jap chisels at different angles.
All are polished to a high shine on the back as are plane blades.
A 60½A gets its second bevel underneath to keep the top angle low.

Sharpening isn't quite the same as friction I don't think. Swarf off a lathe is bloody hot because of the work you're putting in, not from friction I reckon.

The paint brush idea sounds good, but I only have two hands !

lucky you having a wet sharpener, mine has been confiscated and I have been given a state of the art belt sander

 

[Justin Passing]

shallower the angle the sharper the chisel but easier it blunts or chips

Er, well of course.
The angle you want , depends on the materials. A chisel for walnut would be hopeless for soft pine and vice versa. Hence , have more than one set of chisels. I have a couple of singles at really shallow angles. They don't rip the grain out even shaving across the grain, but in something hard the tip would just snap off.

The paint brush idea sounds good, but I only have two hands !

lucky you having a wet sharpener, mine has been confiscated and I have been given a state of the art belt sander

You probably only need one coarse waterproof belt, assuming you finish on a stone, or a sheet of SiC, or diamond pad.

How many hands to hold a chisel? Presumably the sander is fixed - or stick it in a vice.
Once the belt's wet it stays wet for a while
It''s not difficult.

 

[Munroast]

How many hands to hold a chisel? Presumably the sander is fixed - or stick it in a vice.
Once the belt's wet it stays wet for a while
It''s not difficult.

you need two hands to offer the chisel to the belt in a controlled manner (even using the guide) - it was you suggesting applying water to the blade with a paint brush. Obviously not difficult if you have three hands.

 

[fillyboy]

I have three sets of chisels on the go normally, with the number 1 set used for fitting door locks hinges etc. It's not a rare occurrence to find a hidden nail or screw and when that happens I chuck it away and buy a new one.