:: View topic - computer-assited planner core profiler

Hi guys (*)

after months of slow progress, my brother and I finally got our first core profiled on our computer-assisted planner (the wood kind, not the smartphone one). Since it worked pretty well, I though I would try to give back to this community which has been awesome in helping us get this far with our ski project by writing a bit about what we did.

The idea is to use a regular cheap ($200) planner, and to add "instrumentation" to interface it with a computer, so it becomes a super-precise tool to shape cores with any profile. A wheel attached to a rotary encoder (~$35) measures the longitudinal motion of the core in the planner with an accuracy of 100m (approx.), while a similar encoder attached to the vertical screw (the one that moves the planner cutters up and down) measures the position of the cutting plane with an accuracy of 3m (it's REALLY precise). The encoders are attached to an Arduino Diecemilla board ($50) which has a microprocessor that runs a custom software to send the encoders data to a PC via USB. On the PC, another piece of custom software displays the target shape (in this case, measured from an Elan WorldCup SL ski), and overlays a green dot at the current position of the planner cutters. As the core moves into the planner, the operator moves the cutters up and down to keep the green dot on the target shape.

The whole setup works pretty well. We were initially more ambitious and got a stepper motor on the vertical axis of the planner, to get a fully automated system. However, poor engineering judgement (my fault) resulted in an under-speced stepper (not enough torque), so we put that aside and got the encoder on the vertical axis with the operator turning the shaft manually.

We then had to disable the drive on the planner (the chain that turns the cylinders that move the core forward) because the core was moving too fast for the operator to follow. Now, the operator's assistant (my bro) pushes the core in manually, while the operator has plenty of time to follow with the cutters. If we were to do this again, we would (maybe) spend a few $100 extra to get a planner with an adjustable feed speed, but honnestly the setup with the $200 planner works quite well.

I'll post pictures soon. If somebody is really interested, I can post our software for the microprocessor and for the PC, so you can replicate our tool in your own garage.

*: apologies if this is not an all-inclusive greeting, but I somehow get the feeling that it reaches 99% of the people on this site..

This is interesting! Please show us the pics!

YES, please post some pictures and the software! I so want to try this...i even have a couple steppers lying around, so maybe i'll try and make it fully automated.

Btw, stumbled upon this post on CNC Zone:

http://www.cnczone.com/forums/general_cam_discussion/157249-2d_programming_cnc_thickness_planer.html

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The web site won't let me post the pics until I've made two "legitimate" postings... so here's #2.

So awesome chrismp! I love how someone always actually goes and builds the things we dream of!

Thats seriously damn cool, nice work guys. Sounds like it wouldn't be too hard later on to go back to steppers, including the drive drums, so that it's fully automated. Having to manually push it, and move the cutter up and down would get old.

wow! Ill buy one. How much?

can we get a vid of this in action?

Really impressive.

Share as much as you can here or on cnczone.

Thanks.

Nice work, that is sick!

Igneous skis in jackson has a pretty sick setup for planning cores. their planner will move up and down as you push the cores through which are on a tray with rails, similar to the rail system that ski builders shows for using a router tray on rail.

what i understand what igneous did was alter the planner so that the threaded rod which the planner normally moves up and down on was replaced with a simple smooth rod and connected to the planner head with a slid fitting. allowing the planner to move up and down as you push the cores through.

heck yea. Friggen impressive and doesn't take up as much room. I'm in!!!

That is what I have been wanting to do for awhile. Use your router bridge base for the jig for your planner.

Just when you think there are no new ideas!! Would love to see it in action.

PeteMorgan- Do you if Igneous's method cuts the core in 1 pass or mutilple?

I think the igneous setup is based on cam followers.

It would have to do it in multiple passes still I reckon.

The igneous planer is in this vid briefly.

http://www.youtube.com/watch?v=supOiVtlpbE&feature=youtube_gdata_player

yes igneous has to make multiple passes on their cores. they have capabilities of raising and lowing the planer with a lever, quickly so the cores can return to the front of the planer without leaving the rail system.

i am pretty sure there are skateboard wheels incorporated one way or another. probably on the rail system and also probably on the planer head.

they also use skateboard wheels on their bandsaw to redirect their bandsaw balde to go at an angle so they can give their sidewalls a nice smooth rounded look, rather then the 25 degrees that the router bit gives.. off topic. but skateboard wheels are pretty useful apparently.

i hope igneous doesn't mind me blabbing about their ingenuous setups. sorry mike.