Tormek Fixture for Robotic lawnmower blades

[Ringarn67]

A 3dprinted fixture for sharpening robotic lawn mower blades and utility knife blades.
Add Ø5mm neodym magnets.
You may have to adjust the holes with a drill

https://grabcad.com/library/tormek-fixture-for-robotic-lawnmower-blades-1

[RichColvin]

How is it used?

[RickKrung]

Welcome to the forum, a bit belated.  You clearly have some talent when it comes to 3D printing and may be able to make some nice contributions with some additional context and considerations.  Could you share a bit of what you have done with your Tormek? 

Rick

Had a little fun with TormekCalc2, Fusion360 and a BGM-100

Don´t know if all measurement is OK, comments are welcome

STEP-file can be downloaded from here:
https://grabcad.com/library/tormek-fixture-for-robotic-lawnmower-blades-1

I tried to download the file, but could not unless I could log into that site, which I could not and am not going to create an account just to get it.  It would be helpful if the file were posted where it could be downloaded more easily. 

How is it used?

Excellent question.  Hard to appreciate without the context.  Shucks, I don't even know what that type of lawnmower is.

[Ringarn67]

Welcome to the forum, a bit belated.  You clearly have some talent when it comes to 3D printing and may be able to make some nice contributions with some additional context and considerations.  Could you share a bit of what you have done with your Tormek? 

Rick

Thank you
I have sharpen knifes and some chisels, nothing special

I tried to download the file, but could not unless I could log into that site, which I could not and am not going to create an account just to get it.  It would be helpful if the file were posted where it could be downloaded more easily. 

Stlfile and more pictures is attached here

How is it used?

Excellent question.  Hard to appreciate without the context.  Shucks, I don't even know what that type of lawnmower is.

I find it a bit fiddly to adjust the small blades in the holder, now it just snap with magnets.
Pictures attached

[RickKrung]

Very interesting.  The context makes a world of difference.  Never knew such devices existed, but not surprised.  Must take a well surfaces lawn.  How many of those knives are used in it.  What sort of boundaries are required.  Husqvarna is a good quality brand. 

Curious it uses such sharp knives.  Standard lawn mower blades are not usually sharpened with such a keen edge. 

I saw first the utility knife blades, but realize from one above it the lawn mower blades are different.  With that hole, do those blades rotate centrifugally, as in a flail mower? 

Rick

[micha]

Rick, there are 3 blades attached to a rotating plate, basically they're just pivoted on a bolt screw quite loosely. In weight and thickness these are very comparable to utility knife blades, so the principle is basically the same as in rotary (not flail) mowers, but the blades of the latter are way heavier.

Boundaries are made by electrical wire embedded some centimeters in the ground, which carries a signal, usually injected from the charging station.

Depending the type of mower, the blade motor rotates with 2200-2900 rpm. (I always wondered, now that was an occasion to actually look it up)

Ringarn67, that jig is an awesome and very creative idea. Thanks for sharing.

Mike

[RickKrung]

Rick, there are 3 blades attached to a rotating plate, basically they're just pivoted on a bolt screw quite loosely. ...snip...
Mike

Yes, that is the "flail" type motion I was asking about.  I do find it curious that they have sharp edges on two sides, as I would expect the rotating plate to do so only in a single direction. 

Rick

[micha]

Oh, I forgot to mention: these automowers change their rotational direction, so both sides of the blades are used. So there's no need to turn them manually.