Spokeshave Challenge

[RobinW]

Incorrect jig part numbers corrected - thanks for the pointers on how to sort that out.

I have not used an SVM00 and it would not suit a spokeshave blade due to the closed end of this jig and its internal rounded surfaces (similar to one of the woodturning tool jigs).

A friend who has a small milling machine has offered me the use of it, but I have absolutely no room to get it in, and he is too busy with his own job to get it set up in his own workshop. I think even my very accommodating wife would seriously object if it appeared in the kitchen!

[Rob]

ha...thats where my lathe lived for its first month of life....right next to my kitchen diner :-)

It was minus 5 in my shop so I got better half permission to assemble it in the kitchen....it then accidentally remained for a month....until christmas was looming...then it was out into the cold...sniff sniff

[Herman Trivilino]

The SE76 is not designed for blades which cannot extend say 50mm from the jig. The SVM45 knife jig can handle small blades but is susceptible to snatching if the blade is not very wide and the operator goes too far over the stone edge (as I demonstrated!) and can introduce angular issues in grinding as it does not have anything to prevent any shaft rotation.

I'm reading this again this morning and I understand it a bit better.  If the SVM-45 had a shorter handle it would solve all your issues except for the angular rotation?  Rather than fabricate one from scratch it might be easier to modify an existing SVM-45 by removing the handle, filing or machining the round shaft to a different shape, and attaching it to a piece of flat stock that can be clamped into the SE-76.

The really small blades that are hard to hold are still going the be a problem as they won't fit in the SVM-45 and without the ability to rotate the jig you won't be able to sharpen the tips of the blades.

Have you tried clamping a small knife in the jaws of a vise-grip so you could hold it better, and then using the HK-50?  You can make one out of wood that works like a gem.

[RobinW]

I think there are two things here. Small knife blades which need the angular freedom of rotation to follow the curve of the blade - so that is where the SVM45 with existing handle applies, or the HK50 if it suits your style or tool. (I don't have any small knives so that isn't an area of interest to me.)

For the spokeshave blade you need a straight line facility that the SE76 gives you, but as the blades are short front to back they need something like a vice-grip or the front end of the SVM45 which can be used in conjunction with the SE76.

If you had an SVM45, instead of ruining the handle by filing it flat and square, all you need is a replacement bottom plate (drilled and tapped to suit to match the top plate). Keep the top plate with the knobs, screws and springs. Then you have the best of both worlds for both small knives and spokeshave blades.
All good fun and stimulating.

[Herman Trivilino]

If you had an SVM45, instead of ruining the handle by filing it flat and square, all you need is a replacement bottom plate (drilled and tapped to suit to match the top plate).

Good idea, Robin.  I just checked the sharptoolsusa website and unfortunately that particular part doesn't appear to be available.  You'd have to buy the entire SVM-45 jig or fabricate that piece yourself.

[RobinW]

That's the idea - and why I commented that Tormek have the opportunity to add an extra jig to their armoury, where they have the sizes and nearly all the tooling already available. Either they make an extra bottom plate for use with an existing SVM45, or supply a whole new tool. As I already have the SVM45 all I need is a bottom plate. For someone without they need a whole new tool the SVM45SQE (SVM45 with SQuare End). There you are Tormek the model number is also supplied!

I need to ferret around and see who else I know could machine me a bottom plate. (I'm at a reunion on Monday and one of my old colleagues who will be there used to have a well fitted machine shop for mechanical parts - hopefully he'll still operational!)

[Herman Trivilino]

This jig would be good for sharpening things that aren't so small that the SVM-00 would be used for them, but are small enough that they're hard to hold onto?

[RobinW]

My friend Bob has machined a steel plate to my drawing so that I can now turn my SVM45 into a 'SVM45SQE' (SVM45 with Square End) and use it with the SE76 square edge jig, as proposed in my earlier posts with my wooden mock up.

Although not shown in the following photographs, it is machined with counterbores to locate the springs and tightening screw. It has the large locating lugs for aligning the top and bottom plates, and the small lugs against which the blade butts, all as per the SVM45.

The following photos show it in action with a small blade from a Stanley 63 spokeshave. It's now really easy to hold these small sized blades and also gets the advantage of using the SE76 for control and repeatability. Going like a train!





As I suggested previously, Tormek could add this to their range of jigs.

It also strikes me if someone had an SVM45 but not a SE76, they could use this jig with Herman's HK50, so having a firm grip of a small tool which then uses the HK50 for angle alignment onto the stone.

That was a very satisfying afternoon's work.

*I've just come back into this post. As I was about to exit Photobucket, I had a flashing message box which I thought was from Photobucket. Oh no it wasn't. I was hijacked off to something which, when I tried to shut it down, it wouldn't let me. I couldn't Force Quit Safari (Apple's Browser). I couldn't shut down my Mac using commands. In the end it was hold down the power button until I overcame whatever was trying to get hold of my machine. Then on restart, it's clear the History, clear the Cache; clear out the Preferences and Security etc several times and hopefully that's it all killed off. Moral of the story? Don't click on any flashing message box which comes up in Photobucket.

[Herman Trivilino]

Nice work, Robin.  I'll see if I can get one made for myself.

[RobinW]

Would you like my drawing?

[Herman Trivilino]

Yes, I would.

[RobinW]

Let's see if my latest wrestling match with Photobucket works!



It is some years since I did a detailed mechanical drawing for machining purposes, and I have forgotten how to specify tolerances, perpendicular items, and surface finishes, hence the novel tolerance specification note! if I have it right it's drawn in Third Angle.

The plate Bob made for me is 6mm thick which is more than adequate.

[Herman Trivilino]

Looks pretty good to me.  A machinist with this drawing and a SVM-45 on hand ought to be able to make it.

[Ken S]

Clever jig. Robin.  Good show!!!!

Ken

[Elden]

Looks great!
Looks like that would possibly work well with those throw away utility knife blades that aren't worth spending the time on sharpening.