Farquhar Sawmill Model 7 Track and Pulley Setup

[GilMangels]

Does anyone have a diagram or photos to help with setup track and cable pulley system to finish restoring this sawmill. It's a Model 7 Farquhar. Most of the track was rotted and there are insufficient witness marks for accurate setup. Here are pictures of where it is right now. Thank you for any information.

Gil

[beenthere]

Welcome to the Forestry Forum. 
That looks like a very interesting project.

Can you elaborate more about what you are interested in doing here? From the photo's is seems to be a matter of getting timbers cut to the same size and replace any rotted ones. Maybe not seeing the "rotted" ones that have disappeared. 

There are members here with more experience than me. Hope they chime in with their questions. 

I have been following a youtube channel "Tractor Rescue Ranch" of an interesting fellow in western Wyoming that started with just the steel and very little recognizable wood. His mill is up and running but a different brand. Basics likely close to the same as your Farquhar mill. 

[customsawyer]

I can't help with the mill, but judging by the wall behind the mill, you're going to fit right in around here. Welcome to the forum.
P.S. My back started aching just trying to guess the weight on some of those chainsaws.

[Ron Wenrich]

I put in a Farquhar mill about 45 yrs ago.  The track sections came in 10 ft sections.  There were 5 of them.  It looks like you have one at your husk.  You can use that as a template and build 4 more. 

I put that particular mill on pillars with a cross arm to set the tracks on.  Those were spaced 10' apart.  For the log end, you'll want to put in an extra support to handle the extra weight and thumping you'll get when loading logs.  You'll also want to put an old tire at either end of the track.  You'll see why if you ever break a cable. 

When you put in a mill, make sure you are high enough to be able to clean out under your tracks.  You'll also want to have a pit under the blade for sawdust.  You can either use a blower or a sawdust drag chain to move the sawdust out from underneath.  I always preferred a chain. 

You could also opt to change over to all steel for your track.  Not as historically accurate.  Whatever material you use, the track must be straight and level. 

[DanielW]

I've never set up a Farqhuar specifically, but I've set up a quite a few old circular mills, and still own five myself (though two are now disassembled, waiting for me to put them on new pads).

There's really no magic to it. Some measuring is required to set the guided track close enough to the saw plate - I usually set the mandrel square to the track frame, put a straight edge along the fast collar, then measure such that the closest part of the headblock/bunk on the carriage will be about 1/4" to 3/4" from that nominal log-side saw-line (depending on how risqué I feel and how thin of a dog-board I want to cut down to). Setting it between 1/4" and 1/2" allows you to take off 3/4" or 1" dog-boards, but you have to be really confident in your guides and alignment, because even a tiny bit of wander toward the carriage side will send the saw into the carriage (and then send shrapnel everywhere). For my mills at home that I just use for fun, I keep it closer to 1" or so. You'll have to limit your dog-boards to 2" min thickness, but more room for error if something goes awry.

Everything else is just measuring and aligning. Run a wire at decent tension to align your guided track, and fasten the track least every 12" - being sure to check alignment each time you fasten it, working from one end to the other. Make sure your elevation will be sufficient for your carriage bunks to clear your collar. A lot of these old mills were set up to pass just over the collar line. I usually set mine up a little higher, just to give a little more clearance if there's a knot or something sticking down (only really a concern when halving/quartering).

I no longer have wooden frames or bunks on any of my mills; All my mills are now steel frames - no wood at all. To me, it's worth the cost of steel and time welding to have a solid, rigid frame that won't ever vary. But I can certainly understand if you want to restore it on a wood frame to keep it original and save cost. I get the guided track set approximately correct to my wire, then start at one end: I tack the track with the welder, measure the track at that tacked location to my alignment wire, move 12" along, adjust the track position to the wire to be identical to the first location, tack again, then move on down, repeating the process. I also now weld my tracks down rather than bolt them. As long as you're careful with the welder - starting with light tacks and finishing the welding with beads no longer than 1/2" at 12" or so spacing, you'll have no notable distortion. You can easily maintain 1/32" accuracy, which is plenty adequate for these old mills. With the new gangs and twin scraggs I deal with at work we have more precise track alignment methods, but they aren't needed for most old circular headrigs. I prefer an all-steel frame, but there's nothing wrong with setting it up on a well-made wood frame. You just want to be sure to use properly cured and stable wood, and don't expect it to maintain perfect alignment after a few years.

I'll emphasize: Whether you're fastening to wood or steel, you definitely want to be checking and adjusting the track alignment every 12" or so as you fasten it down: Every old mill I've worked on has had warped/bowed tracks. In the worst case (my old Frick) I had to temporarily weld on coupling nuts every few inches, using them as adjusting lugs with jacking bolts to push/pull the track in alignment as I fastened it down. Braided wire is preferable to solid for an alignment wire (though either is probably fine for an old carriage track, as long as you get sufficient tension on it).

This is up to you, but I'd be looking for an inserted tooth saw for that mill. Fixed saws like yours take less power to run, but can sometimes be a pain. If this is just a fun project, you could start with that saw and keep your eyes open for an inserted tooth saw in the long run. It's hard to tell from that picture, but it looks like someone might have got a little creative with the gumming profile on your saw. Looks to be a little long and high up.

For the cable pulley system, the most important thing is to keep the pulleys at either end in alignment such that the cable wraps on an off the drum side-by-side and doesn't wind over top of itself. The cable MUST wrap around the drum side-by-side and never over top of itself. Keeping tension on it is also critical to prevent this. If it's allowed to wrap over top of itself, you've created what's called a 'Chinese Windlass" effect: The cable will be coming off the drum at one diameter and coming on at another. It will thus be coming on the drum at a different rate than it's coming off. In the scenario where it's coming on over top if itself, it will come on at a greater rate than it will come off, but because the diameters are so similar it develops a crazy amount mechanical advantage and pulling force on the tension side. When this happens it'll snap cables, pull apart your end pulleys, tear apart your carriage, etc.

It's hard to tell from your pictures, but it looks like that's running on bearings rather than babbitt? That's a good thing (though nothing wrong with babbitt if well maintained). A lot of mills from that era when manufacturers were moving away from babbitt used long, cylindrical roller style bearings. They work just dandy, but you have to make sure the grease isn't dried up, or the rollers will stop turning, wear flat spots, and start wearing down your shafts. If you need new bearings, 'Berliss' still makes that style of bearing in just about every size you could need or imagine.

If I'm wrong and it's on babbitt, make uber-sure you keep the oil to those babbitt boxes. It only takes a few minutes of running on dry babbitt to heat and start melting the babbitt out of its boxes.