Need advise on my sawmill project

[fluidpowerpro]

My experience has been that 4 posts is much better than 2. When I say 4 posts, its 4 posts to support the whole carriage plus 2 posts that the saw head rides up an down on. This is like whats done on the Hud-son Oscar series of saws. 

[Ljohnsaw]

I have 4 posts and 4 ACME screws. I made some brackets that wrap 3/4 of the way around the uprights. I tucked in some 1/2" thick blocks of UHMW plastic for a low friction fit. It's definitely not a precision fit. IMO, it is fine to wobble about. It's the height that is critical that it be robust.

You can see one behind my scale.

The scale is magnetically stuck to the post with a toggle clamp at the bottom.

[Ken Malone]

How do I add a photo?

[Magicman]

Look at the last item on the Index Page:  How to Post Photos.

[esteadle]

l22

[fluidpowerpro]

I like the 1 HP per tooth in the wood analogy but I think you really need to define cutting speed along with it. 
I have cut a 36" red oak log with my 16 HP mill at an "ok" speed but would love more HP to go faster.
What I think is "ok" I'm sure would be unacceptable to others.
It would be interesting to know what manufacturers use to estimate cutting speed per HP, cutting width, species and blade characteristics. 
I know there are more variables but those are probably the biggies.

[jpassardi]

My personal experience: I upgraded from a Kohler 15 HP to a Kohler 25 HP. I forget the exact numbers but it was about a 40% increase in torque. It cut like a different mill right away, especially in wide cuts. I can now feed quick enough that I'm not making fine powder sawdust on wider hardwood cuts.

[Ken Malone]

I got some 1" 6 tpi acme rod but having a hard time finding nuts for it. any suggestions? I'm in Nova Scotia and there are very few options locally.moose herder id like to see more picks of your complete acme set up if I could.Thanks.oh I scrolled back and see all your pictures.

[Mooseherder]

Here is how mine is attached on both sides with steel plate. 

[fluidpowerpro]

I was going to suggest Surplus Center but they only show 7/8 -6 . Are you sure it's 1"?

[beenthere]

A reasonably good, competent machinist can make the "nut" for your threaded rod.

Have you looked at McMaster-Carr for what they might have?
https://www.mcmaster.com/products/nuts/lead-screws-and-nuts~/acme-lead-screws-and-nuts/?s=acme+nuts

[ladylake]

I got some 1" 6 tpi acme rod but having a hard time finding nuts for it. any suggestions?

Try Roton, they have  all sizes at good prices.  You want to use a bronze acme nut, last way longer.  Steve

[Ken Malone]

Ordered bronze nuts from Roton. Thanks everybody for sugestions. This is the best source for info .I have found. Great to get advice from people who know what there talking about.

[Ken Malone]

Do I need a centrifugal clutch on the motor to drive wheel or just an adjustable idler pulley to engage blade

[jpassardi]

A lever engaged idler pulley is less expensive and less prone to wear out but either will work.

[Ken Malone]

Going with idler pully. Thanks

[Ken Malone]

Any suggestions to pull y ratio and motor size to run acme rods up and down. Using 6 tpi 1" acme.

[Ljohnsaw]

A lot of trial and error for the sprocket sizes. Mine is dual speed via a 12/24 VDC switching. Since you are using 6tpi, I would make a guess that you will probably want to raise at 1"/second at the fastest. So the ACME rod will need to spin about 360 rpm for quick moves and be able to slow down to half that to hit your mark via voltage or a PWM controller.

I have tiny (12 tooth?) sprockets on the rods all connected in a loop. Then a larger sprocket on two on the left side. A smaller loop of chain hooks those to the wheelchair motor. I changed the sprocket on the motor a couple times until I liked the speed and power.

Here is an early picture of the setup with just one rod connected to the motor.

The big sprocket got moved to the motor and replaced with a slightly smaller one.,

[ladylake]

 My mill uses a 1/2 hp 56c motor mounted to a 5 to 1 right angle gearbox with about a 6" no 40 sprocket driving 1 1'4 5 tooth per inch acme screws. The sprockets on the screws are the same size as the gearbox sprocket.  That works out to about 350 RPM on the acme screw. Mine is 5 tpi with  6 tp I'd shoot for 400 RPM Steve 

[Ken Malone]

Now on to idler to engage the drive wheel. Any suggestions and picks would be much appreciated.

[Mooseherder]

Mine is direct drive unfortunately.  I've got my mill tarped up for winter now. We got about 8 inches of snow for Thanksgiving.

[Ken Malone]

No snow yet here in Nova Scotia but she's a comin

[Hilltop366]

I can wait a little longer (a lot longer really) for snow here on the Southwest end of NS, what area are you in Ken?

I wonder how well a riding mower transaxle would hold up as they are not made to use most of the power the engine produces as most of the power is required for the blades, the drive belt is often the weak link but some models are more prone shaping axles or breaking teeth off a trans gear then the gear tooth lays over and jambs in the next go round and forces the case apart. Generally a yard and garden tractor have much tougher transaxles than a riding mower.

[Ken Malone]

Hey hilltop Ken here in upper nine mile river.

I picked up a 14 1/2 briggs horizontal shaft and going to run mill with belt and manual idler pulley.
Just about ready to give her a try.

[Ken Malone]

Is a compression spring needed on the blade tensioner? I was told it is a must but I'm not sure.