Tormek Community Forum

In the Shop => Knife Sharpening => Topic started by: Ringarn67 on February 02, 2021, 11:13:33 AM

Title: Tormek Fixture for Robotic lawnmower blades
Post by: Ringarn67 on February 02, 2021, 11:13:33 AM
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

Title: Re: Tormek Fixture for Robotic lawnmower blades
Post by: RichColvin on February 02, 2021, 11:41:55 AM
How is it used?
Title: Re: Tormek Fixture for Robotic lawnmower blades
Post by: RickKrung on February 02, 2021, 02:20:59 PM
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

Quote from: Ringarn67 on June 02, 2020, 09:11:21 PM
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 (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. 

Quote from: RichColvin on February 02, 2021, 11:41:55 AM
How is it used?

Excellent question.  Hard to appreciate without the context.  Shucks, I don't even know what that type of lawnmower is.
Title: Re: Tormek Fixture for Robotic lawnmower blades
Post by: Ringarn67 on February 03, 2021, 11:22:49 AM
Quote from: RickKrung on February 02, 2021, 02:20:59 PM
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


Quote from: RickKrung on February 02, 2021, 02:20:59 PM
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

Quote from: RickKrung on February 02, 2021, 02:20:59 PM
Quote from: RichColvin on February 02, 2021, 11:41:55 AM
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

Title: Re: Tormek Fixture for Robotic lawnmower blades
Post by: RickKrung on February 03, 2021, 01:19:45 PM
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
Title: Re: Tormek Fixture for Robotic lawnmower blades
Post by: micha on February 03, 2021, 03:03:39 PM
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
Title: Re: Tormek Fixture for Robotic lawnmower blades
Post by: RickKrung on February 03, 2021, 03:23:40 PM
Quote from: micha on February 03, 2021, 03:03:39 PM
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
Title: Re: Tormek Fixture for Robotic lawnmower blades
Post by: micha on February 03, 2021, 03:31:33 PM
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.