[Clockwork]

I've started a new project to build a CNC Resaw/Mini Sawmill. It will handle logs 23" long and 12" in diameter - this size suits my needs perfectly.

The project is still at the rough layout stage. Here's my strategy.

A 3/4" birch plywood table will be attached to the lower heavy duty slide and a guidepiece that will slide in the miter slot on the saw's table. This will produce the action to move the workpiece through the blade and retract for the next cut. I'm calling this the X Axis.

The Z Axis stage is mounted on top of the plywood table. This slide will control the thickness of the cut by moving the fence.

I will continue to post progress photos if there is interest by other members.

[wwendorf]

That's really neat. Please keep posting, you have my interest!

Wade

[ger21]

Do you have to allow for blade drift?

[DonW]

Awesome! I'll be watching this one carefully with great interest!

[Clockwork]

Do you have to allow for blade drift?

Gerry

I'm putting in a provision to rotate the fence slightly to compensate for drift.

This machine is exploring new territory as I don't think there's is anything else out there quite like it.

Won't really know how it will function until it is built. It will most likely require some tweaking toward the end of the project.

A Google search for "CNC Resaw" only brought up about 8 hits which were all for the same industrial grade machine.

[fatal-exception]

I could have used that a few years ago when I needed to make a mile of edge banding...

Neat project! Stick with it.

Paul

[Clockwork]

The electronics are complete.

I had this neat box laying around that was acquired a while back as part of a larger auction that included some mechanical stages I needed at the time. The box contained 3 Rorze RD-O23 drives and a power supply that produces 75V@15A and 5V@1A.

The Rorze drives have a funky inputs. Instead of Step and Dir inputs they require inputs that provide pulse streams for CW and CCW movement. I designed a simple logic circuit (center of first picture) to convert Step and Dir into CW and CCW signals. It works great.

Waiting for a few parts to arrive before I can resume work on the mechanical side.

[Clockwork]

The Mechanical portion is done - works great so far.

Here's a few details:

The X Axis is powered by a 425 oz/in motor via a Kevlar belt. The sprocket ratio is 2.4 to 1.

A 3/4 inch birch plywood table is mounted on the X Axis car and a slide that tracks in the miter slot.

I used a old Incra positioning slide it attach the fence assembly to the Z Axis table. A single adjustment screw allows me to adjust the fence for blade drift. It appears to be very solid. Don't know how it will behave while cutting. Planning to use a couple of De-Sta-Co clamps (if needed) for additional support.

The fence is equipped with holes where the workpeice can be attached using short drywall screws. Will use a sacrificial mounting board for resawing and screw directly into the log with raw timber.

[DonW]

Lookin' Good! Can't wait to see the YouTube video!

:-)

[Clockwork]

Look Mom - No Hands

Did the first cut this afternoon. Found a old Russian Olive log in the firewood pile to play with.

The fence wasn't adjusted to track properly so the cuts weren't as clean as they could be. The CNC stuff performed perfectly.

[DonW]

Fantastic! Congrats...

So how thick were those slices?
How thin do you feel you could go comfortably?

Very slick.

:cheers:

[Clockwork]

I wrote some test code to index at .2 inch so the slices are a little over 1/8 inch. I need a ton of 1/16 inch pieces for what I do.

Don't see any reason (so far) why it won't do what it was intended for.

[Clockwork]

I adjusted the fence to track with the blade and the cuts came out perfect. No visable saw marks on any of the pieces. I think the constant velocity through the whole cut really helps. Light sanding and they're good to go.

Almost ready to try it with expensive wood.

[ger21]

How about some video? And what kind of bandsaw is that?

[Clockwork]

The saw is a Laguna LT18.

Everybody wants to see moving pictures. Perhaps in a week or two.

Need to do some experimenting with the G-Code. I'm currently using a path milling function that has a final bottom and incremental depth/pass. This routine retracts the Z Axis all the way to zero after every pass. Need to modify it so it only retracts enough to clear the blade.

[txcowdog]

Oh Man!!! That is so cool. You are an absolute genius. Congrats on such a fantastic machine. I would love to make something like that to handle 10' logs.

[Clockwork]

Thanks for the kudos.

Laguna Tools sells a accessory they call the "Timber Master". I got the idea to build my machine after looking at the video on their website. It's a manual feed machine that is expandable to accomodate long logs.

You can watch their video by clicking on the text at the bottom of this page:

http://www.lagunatools.com/index.asp...PROD&ProdID=47

It may give you an idea on how to build something that will suit your needs.

[txcowdog]

Thanks for the link. I think something could definitely come from that. I had never considered making a CNC sawmill. This was a GREAT idea.

Looking forward to more of your videos.

[blackbeard52]

Pretty Kool!!! Looks like you could chain drive the y and acheve a great 10 foot log extension

[Clockwork]

How about a chain drive garage door opener to move the log on the y axis. You could use the optical safety sensor to detect the end of the cut. It would retract on its own when the sensor is tripped.

I just installed a Genie DC screw drive opener. It retracts at 3X the speed that it goes down.

You would most likely need two synchronized stepper/servo controlled ballscrews to attach to the log (kinda like the video) and index its position for the next cut on the z axis.