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View Full Version : DIY Skewchigouge grind?



rsser
17th December 2012, 08:42 PM
John Siegel gave them a good wrap and there's a length of Thompson V10 rod gathering dust. See Unconventional Tools at Big Tree Tools - Your Source for Professional Woodturning Tools and Equipment (http://www.bigtreetools.com/articles.html)

The question is how to get Siegel's grind.

The Crown version appears to come with a flat negatively-raked top; Beecham's instructions show a tight-radius hollow grind, but at a guess Siegel's version would work better.

Whatever, it's elegant. Wondering how he got it.

I could just grind a flat on top, to the equator. Don't think a cove matters apart from looks. How to mark the equator? Maybe stick some fine W&D to the faces of the 'good' bench vise and rub the rod to and fro til a bit of the blacking is taken off.

Mobyturns
17th December 2012, 10:03 PM
I have contemplated making one of these. Essentially the Sorby spindle master etc are variants of this tool, just out of thinner stock & not round bar. My thoughts were to grind the top "cove" with a cheap 4" grinding wheel and the bevel shape with the Heligrind fingernail jig for spindle gouges.

rsser
17th December 2012, 10:20 PM
Geez Mt, you've got a Heligrind! That makes you and that I know of. A jig of historical significance.

Agree about the top face cove but not sure why the bevel needs anything more than a platform. Enlighten me.

jimbur
17th December 2012, 11:00 PM
The availability of cheap HSS blanks make it easy to try them out.

Mobyturns
17th December 2012, 11:03 PM
Geez Mt, you've got a Heligrind! That makes you and that I know of. A jig of historical significance.
Agree about the top face cove but not sure why the bevel needs anything more than a platform. Enlighten me.

I still like the Heligrind shape for spindle & detail gouges over other jigs including the Tormek's jigs. Its a shame they aren't still available? Or are they? The Heligrind jig works on the Tormek to btw. :D

No problems with a platform just depends how good one is at freehand sharpening & the repeatability of the shape you want. I don't think the long section profile of the top face matters all that much as long as it is flat & well ground. From my experience with the Sorby spindle masters and the beautiful finish they create, I would be putting a lot of effort into a good shape and finish on the bevel / fingernail profile & honing the flat as well.

Just preferences I guess as I like the Heligrind bevel & fingernail shape and can see some benefits of that shape as a polished fluteless spindle gouge. The Sorby spindle masters don’t handle Aussie hardwoods very well so a polished fluteless spindle gouge seems to be a reasonable compromise offering the best of both. :U

rsser
17th December 2012, 11:34 PM
I remember the Heligrind claims; got one from a forum member, tried it and passed it on to another a while ago.

...

With a rod freehanding the bevel is no drama.

Doing the top, still open to suggestions/corrections.

issatree
18th December 2012, 01:58 AM
Hi All,
I have used one of these for a few years now, & they will cut like a demon.
I made my own from a piece of HSS of JMcJing Steel
10 x 10mm. Although I have a few others as well. One is 80mm. long, & 3 x 3mm. Very useful at times.
I mainly Sharpen on the Flat, but of course the Fingernail Shape has to be redone now & again.
I'm not sure if it was John or Bob Chapman who showed us the Tool in the English Mag. " Woodturning ".
Can't fault the Chinese Steel.
That's my 2sense worth.

artme
18th December 2012, 08:39 AM
Geez Mt, you've got a Heligrind! That makes you and that I know of. A jig of historical significance.

Agree about the top face cove but not sure why the bevel needs anything more than a platform. Enlighten me.

Now you know three!!:D

RETIRED
18th December 2012, 05:48 PM
Unfortunately I don't have the Heligrind. Have the Unijig.

I would like a heligrind though so if any one has one for sale let me know.:)

Ern, to shape your skewji gouge I would put a flat on it and fit it into your gouge holding jig with a longer extension than usual and lift it straight into the wheel. Grind until you nearly meet the halfway point, then just move it back in the jig a bit and do the same until you are near the tip.

This will leave a series of "coves" that can be ground flat.

Another method would be to hold it in vise and using an angle grinder with a narrow cut off wheel slice the bar in half lengthwise and then shape on the grinder.

rsser
18th December 2012, 07:06 PM
Thanks for the advice . Can see either approach working and they're within my capabilities.

When I was younger and stupider I made Oland-type tools by putting a metal grind wheel on the circular saw under a Triton bench to get a flat. Despite PPE it's too risky; you're right in the line of fire.

Jon Siegel has kindly replied to an email request about how he does his:

I grind somewhat less than half way through. I don't have any fancy set-up for doing this, other than a VERY coarse grinding wheel. I use a pocket jig initially to get started, then free-hand I extent the length of the flat out to the tip. Finally I hand hone the top flat, and buff before doing the final grind to the bevel. I do take some off in the final grinding of the bevel, and this removes the inevitable irregularities that occur at the tip.

So that's similar to your approach A.

I guess with the Sorby Pro-Edge and a coarse belt there's the option for approach C (akin to the Triton bodge). Still getting my head around the possibilities of that machine.

hughie
18th December 2012, 07:56 PM
]Geez Mt, you've got a Heligrind! That makes you and that I know of. A jig of [historical significance.


I contemplated making one at some time in the past. But for those may consider it worth a go here's the manual

TTIT
18th December 2012, 10:09 PM
Unfortunately I don't have the Heligrind. Have the Unijig.

I would like a heligrind though so if any one has one for sale let me know.:)

.........................Now he tells me :doh: Donated the one I inherited from the old man to our local club - not that they have used it yet :shrug:

RETIRED
18th December 2012, 11:14 PM
Bugger.

wood hacker
19th December 2012, 08:29 AM
Unfortunately I don't have the Heligrind. Have the Unijig.

I would like a heligrind though so if any one has one for sale let me know.:)





I may have one sitting unused in a drawer in the workshop. Will have a ferret tonight and let you know.

cheers
WH

Mobyturns
19th December 2012, 09:44 AM
Unfortunately I don't have the Heligrind. Have the Unijig.

I would like a heligrind though so if any one has one for sale let me know. ....

You dont have one - really! :p They're just the bee knees for my sharpenng of detail gouges. I guess thats what I have learned to use & they work very well.

Paul39
19th December 2012, 02:02 PM
My thoughts for a grinding jig.

Top sketch: Top view of jig, red is tool clamped between two short boards with V cuts, 2 nails or screws to keep front of tool from moving side to side, sitting on a base.

Middle sketch: Side view, showing relationship to grinding wheel.

Bottom sketch: Showing base with end of tool clamped between two short boards.

To operate, clamp tool in V blocks with a screw on each side and place on base per middle sketch, rig base so that end of tool is resting on top of wheel, slide tool back on base to clear grinder, start grinder and advance tool into wheel and pull back to let cool. Repeat, adjusting base to get desired grind.

Some high speed steels will get microcracks if shocked by dipping in water when hot.

Tool and V block can be removed for inspection and replaced holding the same rotative angle.

A cleat could be put on one or both sides of the base to keep the rear of the tool going straight.

RETIRED
19th December 2012, 04:53 PM


I may have one sitting unused in a drawer in the workshop. Will have a ferret tonight and let you know.

cheers
WHThank you.

rsser
20th December 2012, 04:40 PM
Thanks for your considered replies guys.

Let me say that when problem-solving it helps me to talk things through.

The job's done.

I used the Sorby Pro-Edge. Freehanded the flat with #60 and #120 belts. Possible because the platform ends extend past the belt/platen. Took a while to get the hang of it. About 20 mins all up with fairly worn belts. Then I refined the flat on benchstones to #1000. Another 10 mins worth.

Couldn't get a satisfactory bevel/cutting edge freehand so I used the Sorby gouge jig. That needed a flat on the rod top that mentioned and getting that was the trickiest part of the exercise. Can see why the Yanks go for 'pocket' jigs. Unlike Jon Siegel who looks to have about a 45 degree bevel angle on his I went for about 35. That's what I use to roll a bead with a detail gouge.

Now the thing just needs to go into a handle so a play with it can be had.

NeilS
20th December 2012, 09:25 PM
Geez Mt, you've got a Heligrind! That makes you and that I know of.


Make that 3, not that I use it very often nowadays.

rsser
21st December 2012, 01:52 PM
Why is that Neil?

I recall the claims made for it, that it could do a shape that no other jig could do.

...

Well I crammed the Skewchigouge into a modular handle and had a play last night. Just as 'proof of concept'.

First impressions and note I'm not much of a spindle turner ...

1. It's easier to do a nicely shaped and esp. deep cove cp. a 3/8" (UK measurement) spindle gouge (and this is the same diam. rod). I rolled the tool as you would a spindle gouge. But the finish wasn't good so the bevel got a hone with a fine then extra-fine diamond paddle. Then I did a cove as I gather you would use a Sorby Spindlemaster (ie. face up all the way) and the shape and finish were good.

2. Beads: not so hot but that applies to my use of a skew as well. I do better as noted with a detail gouge, or a B&P tool. Yeah, this is just a matter of practice.

3. V cuts and facing-off end grain to square: I'd take a skew to these tasks anytime.

Upshot: this kind of tool may have a place in your kit. Jon Siegel was right.

I may increase the bevel angle on this to around 45º and see how it performs.

NeilS
21st December 2012, 06:51 PM
Why is that Neil?

I recall the claims made for it, that it could do a shape that no other jig could do.



The Heli-Grind was the only jig (that I knew about) that provided anything other than a straight across gouge grind back when I bought it. It also came with an adjustable platform and skew jig. It was designed particularly for the P&Ns tools which I mostly had at the time, and worked OK with their U flute gouges.

Since moving mostly to V flutes and swept back wings I have been using the 'pivoting' style of jig (as Mike Darlow calls them).

I still use the Heli-Grind platform for scraper tips and spindle roughing gouges, the skew jig for the odd occasion when I use a skew, and it does a nice job on the one gouge that I use with a straight across grind.

So, not my main jig any more, but still too useful to give away to , sorry mate!

RETIRED
21st December 2012, 07:00 PM
So, not my main jig any more, but still too useful to give away to , sorry mate!:p:D

Jonzjob
21st December 2012, 09:32 PM
This thread has given me an idea as to what to do with a piece of HSS rod I have. I think that I will soon have a small skrewedup gouge, or what ever the hell you call it!!

I have already made a round skew and a diamond point tool, so a skrewchi thingy will make a nice trio to try me-thinks? Even if I don't like the thing the rod was only a couple of U.K. beer tokens..

Paul39
22nd December 2012, 02:58 AM
I have a bunch of rods salvaged from Xerox machines and printers that I grind and play with when I see some great and wondrous new tool advertised.

These are high carbon steel, but for testing and shaving off the last bit before sanding they work fine.