My Journey To The Perfect Drag Knife

[walter67]

Wouldn't mind one for my machine, but it's got me thinking. Would a blade like this be more suitable:



You'd probably be able to get rid of the blade clamp and fit it directly into the barrel.

Hi Rye

I did look into using those type of blades before I took the plunge, but after
reading how these drag knifes work, it's all about the offsets, the blade you have pointed out would be perfect for fine detail cut outs, but cutting thicker material
the blade would perform better if it was more angled, i.e. a bit like trying to cut
a thick cake with the knife at 90 degrees instead of 45 sorry for my analogy.

I have also edited my last post with a link to a Youtube video so you can see it
working

[cropwell]

I had a foil cutter, https://www.sorotec.de/shop/Mini-Foil-knife-Vario.html, which I destroyed by trying to cut the wrong material, so I remade it yesterday.



I have yet to try it out, but the principle is simple. the 7x3x2 bearing is clamped by the knurled collar and the 6x3x2 bearing floats in the shaft with the spring applying the cutting pressure, adjusted by the grub screw. The neodymium magnet holds the cutter in.

The only problem with the one from Sorotec was that it was all pressed together and not dismantle-able or repairable.

My thoughts were to use a swivel knife and mount it with a cut down handle in an 8mm collet, but there is too much slop in the thing to be of any use, and it would only cut a minimum of 5mm radius corners as the blade offset was too much.

I like the Donatek clone idea, and I am considering how it could be done with a Swann Morton scalpel blade (cos they are sharp buggers ! and cheap).

[walter67]

Hi

I was asked if would share the Drag Knife plans

here you go..

[Leadhead]

Many thanks for the files. Much appreciated.