Scraper blade sharpening jig

[Clifton C]

Easy sharpening jig to sharpen and shape flat boring bar scraping cutters.

The parts.
The length is cut to fit the sharpening system


In use.


Chuck jaws removed, bar held by slides.
Pointing the end with a small grinder,
a file could be used.


Dish the end so the cutter sits flat.


Drill for the tap used. (Here a #21 drill bit for a 10-32 tap)
This is mild steel, use a lathe tool (point, pyramid or equivalent) to make a starting divot.


Tapping with a tap handle and tap guide.
Turn tap in about half a turn, stop and back out the tap till you feel the chip clear.
This is like two steps forward, one step back. Don’t forget oil…



Another way to tap.
Tapping without a tap handle and tap guide.
With tap in the Jacobs chuck, seat Jacobs chuck in tailstock quill, retract quill slowly until chuck “just” self ejects, then stop, lock quill.
The chuck should be able to turn in the quill. Bring the tailstock up till tap is almost in the drilled hole.
Use the Jacobs chuck body as the tap handle and tap the hole. If using a keyless chuck hold the back ring when backing out the tap.


A few more ideas...

 

[Don Wattenhofer]

A much simpler and I think safer method is to use a platform rest.

 

[Doug Freeman]

I use a tormek knockoff and tormek gouge jig to resharpen gouges. The jig also comes with parts to convert it for sharpening scraper inserts as pictured above. The issue is the resulting bevel angle changes as the edge/bolt hole radius changes. I like to put a burnished hook on my scrapers, and honing a variable bevel angle is a pita. I use the bench grinder platform instead. It gives a constant bevel angle regardless of the edge/bolt hole radius. Not sure its safer than the jig shown, but does result in a constant bevel angle.

 

[Don Wattenhofer]

I use a tormek knockoff and tormek gouge jig to resharpen gouges. The jig also comes with parts to convert it for sharpening scraper inserts as pictured above. The issue is the resulting bevel angle changes as the edge/bolt hole radius changes. I like to put a burnished hook on my scrapers, and honing a variable bevel angle is a pita. I use the bench grinder platform instead. It gives a constant bevel angle regardless of the edge/bolt hole radius. Not sure its safer than the jig shown, but does result in a constant bevel angle.

The unsafe part of the jig as I see it would be trying to rotate/feed the cutter with only that rod to grip. The variable angle is a problem also since I don't have any scrapers that I don't roll a burr on.

 

[hockenbery]

looks like a good idea for some experienced turners.
I can see where a novice could get hurt with this set up.

when I’m shaping new scrapers and cutters i hold them with vice grips and use the platform for support.
the vice grip hold has to be repositioned to shape and sharpen the the las 1/3 of the scrapers.
once mounted on the bars i use the platform for support and move the bar to sharpen them.