Heligrind jig question. ........

[smiife]

Hi guys , does anyone know if the heligrind jig is capable of doing a 40/40 grind ?
Any help would be appreciated , any one got a heligrind ?

[Mobyturns]

I only use my Heligrind to sharpen skews and spindle detail gouges. :cool: Hardly know how to sharpen a bowl gouge. :p

Seriously though, I doubt it will do a 40/40 grind in the helical jig mount, but it could certainly be done freehand on the Heligrind platform.

Hope these help,

http://www.dmwoodturners.com/wp-content/uploads/2016/11/Batty_40-40_Gouge_sharpening_illustrated.pdf

https://www.petermiao.com/news/2017/11/11/a-jig-for-4040-grind

[tony_A]

A few days after smiife's first thread on the 40/40 grind, one of Stuart Batty's vids popped up on my youtube play list.
Stuart was one of my preferred youtubers when I was learning to turn and with smiife's thread fresh in my mind I watched it, refreshing my memory / picking up a couple of points I missed 18 months ago. Ever noticed that often we are not as correct as we think we are.
One point that I missed earlier is that the 40 degree bevel needs to be consistent around the edge of the gouge so that as the gouge is twisted to open or close the cutting edge it continues to ride on the bevel and cut evenly. Otherwise the handle of the gouge has to swing in or out as you twist to maintain an even bevel riding cut.
I have been using a Tormek gouge jig which I set to give 40 degree sweep on the wings and 40 degree bevel at the centre of the gouge. (I have a memory of Stuart saying on one of his vids that the tormek wasn't perfect but was one of the better jigs for the 40/40 grind) However, when I checked the bevel angle around gouge I found that it changes continuously from the centre of the gouge to the end of the wings.
The 40/40 grind has two different motions, a sweep and a twist that are independent of each other, making it quite complex to replicate with a jig.
My conclusion from all this is that learning to grind the bowl gouge freehand is probably the best option compared to buying an expensive jig that you know isn't exactly correct. Your freehand grind can be a little off the mark and no worse than a jig grind. Being able to remove the gouge from the handle would make hand sharpening easier and I feel that spending money on a good removable handle and gouge along with a grinding platform would be a good option.
I find that the Tormek grind is OK to work with but I understand its weakness now. I have never been able to put a finishing cut on a bowl like Stuart and probably never will so the Tormek is close enough for me.

Tony

[smiife]

I only use my Heligrind to sharpen skews and spindle detail gouges. :cool: Hardly know how to sharpen a bowl gouge. :p

Seriously though, I doubt it will do a 40/40 grind in the helical jig mount, but it could certainly be done freehand on the Heligrind platform.

Hope these help,

http://www.dmwoodturners.com/wp-content/uploads/2016/11/Batty_40-40_Gouge_sharpening_illustrated.pdf

https://www.petermiao.com/news/2017/11/11/a-jig-for-4040-grind

Hi moby , thanks for the info on 40/40 grind , I think that the heligrind isn, t
going to work , so it, s a bit of an expensive platform to use for freehand !


A few days after smiife's first thread on the 40/40 grind, one of Stuart Batty's vids popped up on my youtube play list.
Stuart was one of my preferred youtubers when I was learning to turn and with smiife's thread fresh in my mind I watched it, refreshing my memory / picking up a couple of points I missed 18 months ago. Ever noticed that often we are not as correct as we think we are.
One point that I missed earlier is that the 40 degree bevel needs to be consistent around the edge of the gouge so that as the gouge is twisted to open or close the cutting edge it continues to ride on the bevel and cut evenly. Otherwise the handle of the gouge has to swing in or out as you twist to maintain an even bevel riding cut.
I have been using a Tormek gouge jig which I set to give 40 degree sweep on the wings and 40 degree bevel at the centre of the gouge. (I have a memory of Stuart saying on one of his vids that the tormek wasn't perfect but was one of the better jigs for the 40/40 grind) However, when I checked the bevel angle around gouge I found that it changes continuously from the centre of the gouge to the end of the wings.
The 40/40 grind has two different motions, a sweep and a twist that are independent of each other, making it quite complex to replicate with a jig.
My conclusion from all this is that learning to grind the bowl gouge freehand is probably the best option compared to buying an expensive jig that you know isn't exactly correct. Your freehand grind can be a little off the mark and no worse than a jig grind. Being able to remove the gouge from the handle would make hand sharpening easier and I feel that spending money on a good removable handle and gouge along with a grinding platform would be a good option.
I find that the Tormek grind is OK to work with but I understand its weakness now. I have never been able to put a finishing cut on a bowl like Stuart and probably never will so the Tormek is close enough for me.

Tony

Hi Tony , I think freehand is going to be the way to go , I have some old chisels
to practice on first and see how I go ......
Thanks for your reply much appreciated. ?