cnc shaper

[greenail]

I've been thinking of something a bit useless but perhaps a fun project.... A cnc controlled shaper! I am sure some purists may have just vomited on their keyboards. A few things that could be done that may be interesting:

1. cnc control of the tool angle
2. cutting both directions
3. servo to ensure tool lift for carbide insert tooling.
4. g-code extensions
5. an A axis

"crazy town"

1. linear motor
2. ?

I can't find anyone attempting this anywhere. If someone knows of a build please post it!

is this a crazy idea?

 

[C-Bag]

I didn't vomit on my keyboard so I guess I'm not that much of a purist but I do wonder if any of these proposed interesting things would improve the function? One man's interesting thing is another man's blank stare. I personally don't use carbide on any of my machine tools and so far have not needed to. Relying on carbide tooling would imply you are going to speed up the shaper to I could only guess a frantic pace. This much weight reciprocating that fast and trying to keep it accurate seems like messing with Mother Nature. I don't want to dampen your enthusiasm because I know what it's like to have that kind of "light bulb" go off in my head too but I'd not do this to some Old Iron as you would be working against its intended function IMHO. I think this might have been one of the reasons the shaper design was abandoned but I don't know for sure.

The things I love about my shaper is using inexpensive HSS tooling I grind myself and that it has no electronic black boxes that foul up and I can't fix. All the mechanical problems I've been able to fix. So if you come up with a better mousetrap, cool, please post.

The thing I would most want to add to my 7b would be an automatic down feed. I of course would do it analog mechanically like the rest of the machine. That's my limitation and I'm ok with that.

I wish you the best of luck and hope to see what you come up with here.

 

[Bob Korves]

ABOMINATION!!!

Seriously, keep us in the loop and post your progress with the project. Sounds interesting.

 

[f350ca]

A stepper motor on the down feed might have a lot of merit. I've thought about doing it mechanically but this might be a lot easier.
I already have a DRO on my 18 inch Peerless, one step toward the 21st century.

Greg

 

[C-Bag]

you could be right Greg. The stepper would still involve a gear train for the stepper and that whole thing going with the ram back and forth makes my head swim with peril. The problem with the downfeed for me is the play in the leadscrew and the havoc with that whole thing. One thing that was mentioned elsewhere was on somebody else's shaper the auto feed in on the knee. Feeding up. That would solve several problems in that there wouldn't be stuff mounted to the ram and not having to deal with either making the gibs so tight on the cutter head so it doesn't wander from gravity and the pull of the cut. There is also more room for a stepper motor on the 7b down where the knee adjuster is. A DRO would be nice too.

 

[f350ca]

I have auto feed on the knee but down feed on the cutter would be great when cutting dove tails or when I made the racks for my cnc plasma table. I had the head swung 14 1/2 degree and plunged the tooth, over and over and over for about 5 foot of rack.
Im not a programer or electronic expert, but couldn't a processor over feed the down stroke then retract to remove slack in the screw nut combination so that it can't dig in. That would all have to happen on the return stroke.

Greg

 

[JimDawson]

Sure, why not. Sounds like a fun project, and a great engineering excersize.

 

[C-Bag]

hmm, I'd not thought about needing the angle feed that could only be done with the cutter head. But you are right and that mechanism of tightening and loosening the gib is what's got me stumped because without that I've learned the hard way I'm inducing error. I think my idea for a mechanical downfeed would work, it's the tightening and loosening of the gib.....

BTW, glad to see you back Greg.

 

[greenail]

I didn't vomit on my keyboard so I guess I'm not that much of a purist but I do wonder if any of these proposed interesting things would improve the function?

the idea is almost as impractical as the hand shaper! the goal would be to learn but i'm not quire sure what yet

One man's interesting thing is another man's blank stare. I personally don't use carbide on any of my machine tools and so far have not needed to. Relying on carbide tooling would imply you are going to speed up the shaper to I could only guess a frantic pace. This much weight reciprocating that fast and trying to keep it accurate seems like messing with Mother Nature.

the acceleration control would be something interesting to model in the controller. The nice thing about doing a shaper with CNC is that you could adapt the acceleration curve to the job/tooling/stroke which may improve the results. A mechanical shaper is limited in how much you can control the curve by the drive mechanism which is fixed in most shapers i've seen (fixed based on stroke length).

I don't want to dampen your enthusiasm because I know what it's like to have that kind of "light bulb" go off in my head too but I'd not do this to some Old Iron as you would be working against its intended function IMHO. I think this might have been one of the reasons the shaper design was abandoned but I don't know for sure.

i'm not thinking of modifying an old shaper but building one, likely a very small one, from scratch.

The things I love about my shaper is using inexpensive HSS tooling I grind myself and that it has no electronic black boxes that foul up and I can't fix. All the mechanical problems I've been able to fix. So if you come up with a better mousetrap, cool, please post.

The thing I would most want to add to my 7b would be an automatic down feed. I of course would do it analog mechanically like the rest of the machine. That's my limitation and I'm ok with that.

I wish you the best of luck and hope to see what you come up with here.

it is just an idea at this point. thanks for the feedback.

 

[greenail]

hmm, I'd not thought about needing the angle feed that could only be done with the cutter head. But you are right and that mechanism of tightening and loosening the gib is what's got me stumped because without that I've learned the hard way I'm inducing error. I think my idea for a mechanical downfeed would work, it's the tightening and loosening of the gib.....

BTW, glad to see you back Greg.

You could have a servo kick the gib lock AND also build a knee feed!