Home Built Mill Thread - Let's see 'em!

[VB-Milling]

I wanted to paint before assembly (and to make it pretty), figured I might save some time even though I have to grind and weld a few more things on.

I'm with ya.  The trailer I fabbed up is in the same state.  Everywhere I ground off the galv and welded has been rusting...and rusting more.  

[Gere Flewelling]

I have had terrible luck with POR15.  Not with the product, but the container.  Every can I have ever purchased has required destroying the lid to get it open the first time.  Then what ever product you don't use hardens up before you have a chance to use it again.  After struggling with this for some time, I was advised by a NAPA counter person that I should try the SEM brand "Rust Trap" paint.  It seems to work exactly the same as the POR15, right down to the "runs like water" when brushing it on.  The good part is that it costs less per quart, comes in black or gray, and best of all it comes in a brake fluid type can with a small screw on lid.  The lid will stick some but can easily be opened with a pair of pliers.  I usually dump some in a plastic quart paint mixing container and brush on what I need and then dump it right back into the can.  Almost no waste of the product.  The gray color requires a welding rod to stir it up as it settles out when new.  The cans do have a ball in them like a rattle can, but still needs to be stirred up when first opened.  The black seems to stay stirred.  I have used many quarts of this product the last couple of years and believe it is the best rust sealer paint out there at this time.
Don't get any on you as it takes days to get it off your hands and it never comes out of your clothes.  :-\ 

[VB-Milling]

Thanks @Gere Flewelling

I haven't opened my 6 pack of POR15.  If I can return it, and find the SEM product locally, I'll give it a shot.

[rastis]

One drawback to POR15 is it is not UV protected. Unless they've changed the formulation since I used it last.

[ajsawyer]

One drawback to POR15 is it is not UV protected. Unless they've changed the formulation since I used it last.

That's why I put 2 coats of rustoleum on top of it, turned out to color match really well. 

[marty3d]

So, here is mine.  I started with a kit for the sawframe itself, the rest is my design/work.  I tend to get carried away...  

It will cut a 36" x 16'6" log on its trailer mounted bed.  I built an extension that allows 20ft logs and I am extending that right now to do 24ft for one particular customer.  It has a 22hp Predator engine that is running just fine so far.

I designed the setworks to be microprocessor controlled - I can position the saw using a joystick and I can set the carriage in motion in either direction with a knob.  I also have a separate box for AutoCut and AutoReturn.  AutoCut starts and marks the beginning of the log, cuts to the end and stops - raising up a half inch to get ready to eject the board.  AutoReturn marks the end of the log and pushes the board off the end.  When the saw gets 2" past the start, it stops and drops down for the next cut.

The mill has a hydraulic setup for setting the stops, pushing the log over and clamping it in place.  It also turns the log and raises/lowers the toeboard.

Other than the saw itself, the hydraulics, lift motor, and track motor are all 24v DC electric.  Two car

 

 

 

 batteries in a box and a 110vac to 24VDC power supply keep things going.

[Crusarius]

Marty, I would love to see more details on what you did. the few pictures you posted looks top notch.

[boardmaker]

That looks awesome Marty.   Good job!

[marty3d]

Here are a couple more detail photos.  The carriage drives using two #35 roller chains, some sprockets, etc.  A nice feature is that one end is hard-connected to the frame.  The other end just runs over a quartered section of a sprocket and is secured by just a bungee cord.  That way, I can add or take out an extension without having to fuss with the chain.  I just finished modifying an extension to do 24ft rafters for a customer - it is pictured.  It is supported by trailer jacks so I can align it with the mill.  Easy.

 

 
 

 

 
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So, I had this brainstorm while trying to attach the encoder to the carriage drive motor.  Look closely and you see the motor (which has a metric allen head machine screw attaching the sprocket to its shaft, a metric 3/8" drive allen socket, a 3/8" socket drive to a 1/4" hex shaft, a bit of hose, and a hose clamp.  Totally works.

[marty3d]

Time to try a video - here is a link:  Boomer & Claw   This is my boom truck and the hydraulic claw I built to pick up logs.

And, another link:  Mill hydraulics demo

[ajsawyer]

Your chain drive sprocket is reversed from mine, I have a 54t driving a 15t. Could the stripped lift nuts have to do with the torque on the lift rods?

[marty3d]

No.  Torque is 90% dependent on the amount of lift, and then friction - grease, etc.  Our two systems are quite comparable, although you have a very slow driver that you have to speed up, and I have a very fast driver that I have to slow down.  When it was working, it would drop the saw down by a very precise 1-5/8" to start the next cut - automatically - in less than a second.  

That said, the amount of lift exerted by the Acme rod is also related to sliding friction - which should not be very high with greased steel on steel.  I am looking into that.