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jack forsberg
12-11-2020, 9:59 PM
I don’t believe the Americans ever adopted the French head spindle. Basically a high speed scraper that used 01 steel. Because the steel projected slightly ahead of center it created a scraping cut. In fact you would even burnish a hook on the profile. These rapidly produced short run moldings Because only a one night cut was necessary. The back slightly tucked in from the primary edge.I am delighted that one of my followers has gifted one do the #wadkintemple. I hope to demonstrate how it cuts and how I grind a knife for this unique spindle for the spindle moulder or as you Americans like to call them a shaper .


https://youtu.be/K9j9JU5sZjI

Steve Rozmiarek
12-12-2020, 7:05 PM
Jack, you mentioned that its good for short runs, is it hard on edges or because it's just easy to grind?

jack forsberg
12-12-2020, 7:44 PM
Steve it has to do with the geometry. Unlike a cutting tool that has a hook or progressive angle of attack this cutter is actually a negative rake. Imagine using a card scraper and it is leaned forward to make the cut unlike a hand plan iron . The hook from burnishing creates the shaving but also produces a lot of heat. It’s also milder steel then HSS which is easy to grind Quickly but dulls quickly. Add to that that it is only a single knife doing all of the cutting as the back of the knife or the other wing is tucked in and does not work it only balances the cutter. I’ll post some pictures for the group to see but be aware that I cannot see them so if you wish to ask questions please describe the picture to . me. 446957 Here’s some examples of some of the knives. You’ll notice that in some cases they’re not symmetrically ground because only the one side does the cut . Extremely important that high-speed steel is not used here446958Here’s my body Bruno doing a pretty scary cat with a rather tall knife. In fact he did not have stock tall enough and stack knives on top of each other. The advantage is the quickness at which these can be produced and they are very good at Squirrley grain. 446959446960