Twisted Square Column

[bergerud]

I was thinking about the conversion problem from real world 3D to rotary jig. I wondered what type of surface would carve to be a square. I plotted a twisted square column in a math program called Maple and converted it to what I believe will produce it on the rotary jig. I am hoping someone with the rotary jig will give it a go.

[bergerud]

I just carved the twisted square column. This is the first test of my prototype rotary jig. The dowel was 2 inch diameter and 6 inches long. The jig will hold pretty well any diameter or length dowel which fits in the machine. The jig was in the machine from start to finish. The machine measured the dowel (also, the bit touched down on the dowel for the depth measurement). Even though the prototype is crude, I am pretty happy with the outcome. Look how well the end of the carve lined up.

[Kenm810]

Definitely Impressive!! -- Nice Job on your Prototype

[bergerud]

I watched the videos. There is no problem to do that. The cutting only went as deep as the center hole. As long as the difference in radius of the dowel and the hole was less that 0.8" for carving or 1" for cutting, I do not see a problem.

The interesting problem (sorry - geek here) is to carve through the gaps to carve the back of the other side. To end up with spirals that have a circular cross sections. Of course this will severely limit the size of the thing but, I think it can be done.

That Legacy machine looks pretty cool. (A real 4 axis not just x traded for theta like the rotary jig.). I cannot say that interface looked very user friendly!

[Ilonaco]

I just happened on your post. I do the same thing using a spindlel sander. I'd be interested in seeing your prototype when you get it finished.
Thanks
Dominic Bruno
Land O Lakes FL.

[ktjwilliams]

Big Ups to Both ED and DAN !!!! In any case, Great job by both of U guyzzzz !!! Reminds me of an old Sears spiral crafter... Except that these are automatic and U don't have to stand there turning a crank and adjusting ur router...

[CarverJerry]

Now that came out really good. Ya gonna show off your jig at all, looks interesting from what little we can see and I like the idea of variable sizes too.

[bergerud]

Ok, here is a picture. You cannot see all of the parts. I am hesitant to post the jig details. I do not want to get anybody upset. I am not trying to compete with Ed's rotary jig or damage his sales. I am really interested in the math involved and the problem of making a versatile jig for myself. I have much yet to do. I was going through the measurement routine and it made it through! I could not help but to try and carve something.

[liquidguitars]

Thats cool I see you raised the power drive a little with adjustable y... perfect indexing 2.
I do expect to see a lot more rotor jigs down the road, that's the nature of the design application I think.

[DickB]

Very cool.