Easy 14-16' top slab milling rails.

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MR4WD

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Currently I'm using an extension ladder as the first slabbing bracket, but it only nets me 10-11' boards. I'm after some convienient (to store and transport) rails that will get me 14-16' top slabs. I'm all about the fast setup too!

Post (or repost) what works for you!

Thanks,
Chad.

Edit: Using an Alaskan Mill;
 
Currently I'm using an extension ladder as the first slabbing bracket, but it only nets me 10-11' boards. I'm after some convienient (to store and transport) rails that will get me 14-16' top slabs. I'm all about the fast setup too! Post (or repost) what works for you!

I use 2 lengths of 20' long unistrut cut in half so I have 2 pairs of 10 ft long rails held together by all thread. I can bolt the pair together with 2-3 ft overlap to mill a 16 ft long log.
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More pics here.

Here's one I made from an extension ladder with the two halves being the same width - It's about 18 ft long.
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More details here.
 
I use 2 lengths of 20' long unistrut cut in half so I have 2 pairs of 10 ft long rails held together by all thread. I can bolt the pair together with 2-3 ft overlap to mill a 16 ft long log.
More pics here.

Here's one I made from an extension ladder with the two halves being the same width - It's about 18 ft long.
More details here.

I wad hoping you'd reply-- Which do you prefer and why?

With my ladder set up, I find that when trying to mill with the pith, one end of the ladder sits in the air, so to speak. The big heavy powerhead either sags one side, or the chain draws the ladder into the log, invariably making an un-level cut. Obviously, when the whole ladder sits on the trunk of the log, the rungs support the ladder, making a level, even cut the entire length...
 
I wad hoping you'd reply-- Which do you prefer and why?

Unistrut on threaded rod V ally ladder
Pro, Unistrut Bends less than cheap ladder and more than expensive ladder in the vertical direction over longer span, adjustable for width of log (this is important see below), stronger fixing to log ends
Con, Unistrut is MUCH heavier than ladder, twists more than ladder but can be held firm with strong fixing to log, more expensive than cheap ladder - less than expensive ladder

Overall the unistrut is better than the ladder provided I don't have to carry the unistrut too far.

With my ladder set up, I find that when trying to mill with the pith, one end of the ladder sits in the air, so to speak. The big heavy powerhead either sags one side, or the chain draws the ladder into the log, invariably making an un-level cut. Obviously, when the whole ladder sits on the trunk of the log, the rungs support the ladder, making a level, even cut the entire length...

Here is what I do with rails.

1) Place ladder on log and using a screwdriver mark the bar either sides of the rungs or all thread rod
2) Remove ladder and cut notches in the top of the log between the marks
3) Replace ladder and make sure that most of the ladder legs are resting on trunk.
Clamp the ends of the ladder to the log - clamping mechanism shown in post 2 above.
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To stop the powerhead from slamming the mill into the ladder (a flaw with most mills!) you need a different mill design with wheels - like this.
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By making the rails narrower than the log the wheels on the verticals ensure the mill hits the log before the powerhead hits the rails.

When milling the top half of the log the black wheels stop the mill from contacting with the rails.
When milling the bottom half of the log wheels are needed in a different place - like the white ones shown here. The location of the white wheels need to be adjustable to cope with different thickness slabs/boards

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Details here - make sure you read to the end of the thread.
 
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I am also using superstrut. I use 10 footers for short logs and 20 footers for the longer logs. On the twenty footers I use slotted deep channel and bolt two rails back to back for stiffness. I still have to use a variety of stiffining methods for long spans. Here is a pic. I have to admit that these are heavy and difficult to move around much. I would rate them low for portability.

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If you do a search on "superstrut" you will see some great threads on rails from Bobl and others...
 
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Dallasm, when I saw your pic, the scene reminded me of my milling holiday in Jan. It's amazing that you are on the other side of the world with different trees but the basic scene looks almost identical.

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One difference is I can smell the coniferous resin in your photo, while the trees being milled in my photo smell of a sweet beery aroma, a bit like Corona beer!
 
Dallasm, when I saw your pic, the scene reminded me of my milling holiday in Jan. It's amazing that you are on the other side of the world with different trees but the basic scene looks almost identical.

attachment.php


One difference is I can smell the coniferous resin in your photo, while the trees being milled in my photo smell of a sweet beery aroma, a bit like Corona beer!

That could be my back yard! Except for the extra hands! Most of the time it is just me and the birds out here.. Amazing similarity.
 
So I'm faced with the difficult task of milling up some 42ft logs for our next project. We can cut them down to a 32ft and 10ft pieces, but need 32ft for the finished beam.

What would you guys use for a situation thats longer than the 20ft superstrut would handle?


I was thinking of:

A.) Two 40ft pieces of 2"x4"x1/8" wall steel tubing since it's readily availible

B.) Lag bolts and a guide board ala Maloffs technique
 
Thanks for the replies. Looks like I'm off to find some unistrut and report back!

Hey dallas, where the heck does a guy mill in Point Roberts?! I thought that place was full. I never made it down there, but I spent 6 months in tswwassen building that big powerline last summer.
 
So I'm faced with the difficult task of milling up some 42ft logs for our next project. We can cut them down to a 32ft and 10ft pieces, but need 32ft for the finished beam.

What would you guys use for a situation thats longer than the 20ft superstrut would handle?


I was thinking of:

A.) Two 40ft pieces of 2"x4"x1/8" wall steel tubing since it's readily availible

B.) Lag bolts and a guide board ala Maloffs technique

I'd go for A) or 4 pieces of 20' unistrut would also do it.
 
:)
Thanks for the replies. Looks like I'm off to find some unistrut and report back!

Hey dallas, where the heck does a guy mill in Point Roberts?! I thought that place was full. I never made it down there, but I spent 6 months in tswwassen building that big powerline last summer.


Tsawwassen IS full, but once you cross the border into Point Roberts, it is like stepping into a time warp. Very few people (in the winter anyways) and low development. We are heavily treed with 2nd and 3rd growth timber. It is a special place, where I can see the whales in the bay or look up to see a bald eagle nest. But don't tell anyone. :)
 
So I'm faced with the difficult task of milling up some 42ft logs for our next project. We can cut them down to a 32ft and 10ft pieces, but need 32ft for the finished beam.

What would you guys use for a situation thats longer than the 20ft superstrut would handle?


I was thinking of:

A.) Two 40ft pieces of 2"x4"x1/8" wall steel tubing since it's readily availible

B.) Lag bolts and a guide board ala Maloffs technique

Two 40 footers would be HEAVY. You might be able to combine both methods, using superstrut or lighter tubing in shorter lengths, then mount them with a space between them in order to reach from end to end, then use the Maloff guide board on top of that...
 
Two 40 footers would be HEAVY. You might be able to combine both methods, using superstrut or lighter tubing in shorter lengths, then mount them with a space between them in order to reach from end to end, then use the Maloff guide board on top of that...

I'd go ally unistrut, in Oz it costs about the same as the steel - If I'd known that I would have bought ally instead of steel
 
I use 2x4s scabbed together with 3" deck screws. You'll need to have cross pieces fastened perpendicular to the end of the log to support the 2x4s, and then tie your long spans together across the log(looks like a ladder) with 2x4s to prevent sag and dampen vibration. Allow an extra foot of overhang on each end to support the mill when cutting into and out of the log.
 
What gauge unistrut

Hi Bob,

Thanks for the diagrams and pictures of your setup....always well done and always very appreciated.

What gauge and size unistrut channel are you using? It looks like the 1 5/8' stuff and 12ga?
 
1 5/8 is correct, I don't know about the gauge but it's 0.1" thick.


I checked a few of my resources, and that stuff is fairly cost prohibitive if you're buying new. Still have a few calls to make though... Sure seems handy considering the amount of different fittings you can get for it, plus the overall ease of use... (AND storage when not it use)

I like the way dallas built his rails, doubling up vertically instead of pairing horizontally... Other than the weight.

In retrospect bob, anything you'd change about your Unistrut mill rails?

Thanks,
Chad.
 
The doubled up rails would be much stiffer and require less support if I welded them but then they would be permanent. I am still considereing that.
 
I checked a few of my resources, and that stuff is fairly cost prohibitive if you're buying new. Still have a few calls to make though... Sure seems handy considering the amount of different fittings you can get for it, plus the overall ease of use... (AND storage when not it use)

I like the way dallas built his rails, doubling up vertically instead of pairing horizontally... Other than the weight.

In retrospect bob, anything you'd change about your Unistrut mill rails?

Thanks,
Chad.

Yeah I use my rails for almost every slab since they reduce friction and avoid sawdust pileups on top of the log, and they keep the subsequent slabs straight and parallel, so I'd think about getting ally rails as well.

I'd use the steel ones for the first cut because of the strength and then the ally ones for cutting down on top of slabs.

I can get 20 ft ally rails with a similar profile as unistrut for about $50 each.

I used to worry about the unistrut with all thread rod twisting too much and making the slab twist as well but everything twists (even ladders over more than a couple of meters).

I used to use an angle finder and square to fix the same angles at both ends. Now I lock the angle iron cross brace at one end of the log to zero and place the angle finder on the angle iron cross brace and tucked up hard against the unistrut as shown in the picture. Then I take the angle finder up the other end of the log place the angle finder on angle iron cross brace and twist the unistrut till the angle on the angle iron cross brace is zero and then lock it to the log. Works a treat.

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