farmblog towards actually sustainable farming in Ahualoa

I’ve spent a couple weeks researching, and this is what I’ve learned about milling your own wood with a chainsaw, and in particular a battery-powered chainsaw. Note that I have not actually done any milling yet, but after so much reading, searching, shopping and youtube-ing, I feel like I’ve learned enough to share and be useful.

First of all, some people will dismiss it completely, saying that chainsaw milling is too tedious, too slow, too limited. They point out a proper bandsaw mill is more efficient, faster, better, etc. No doubt they are right, but many of us already own a chainsaw and want to mill, and don’t have thousands of dollars for a “real” mill, or just aren’t going to mill often enough to justify buying one.

There are four kinds of chainsaw mill, from most serious/expensive to least serious/cheapest:

1. “Alaskan” horizontal milling rigs, which attach to your chainsaw bar in two places
2. “Alaskan small log” horizontal milling rig, which attaches in one place
3. “Edging” mill rigs, which cut vertically with the saw in a fixed orientation
4. Cheap vertical rigs which slide down a 2×4 with the saw able to rotate

Type 1: “Alaskan” Horizontal Mill

The quality models are made in the USA by Granberg, and cost around $300. There are many Chinese imitations on Amazon which can cost more like $100 and look like this:

By all accounts, this type of mill works well enough, as long as you have a powerful chainsaw, and are patient enough for the many steps, slow cutting, a lot of gas and chain sharpening, etc. Many people say you shouldn’t even attempt this with a battery chainsaw, because the saw isn’t powerful enough, but there is another major issue: bar length. I borrowed my neighbor’s 36″ Granberg rig, attached it to my battery saw with 18″ bar, and this is what it looked like:

As you can see, this rig is just too big for the 14-18″ bar typical of a battery chainsaw, and worse, the metal parts that clamp onto the bar are as wide as the bar, which pinches the chain. By attaching in two places on an 18″ bar, there is less than 11″ of bar left to mill with:

Type 2: The Granberg “Small Log” Mill (G777)

It costs around $170-$270 depending on shipping and where you buy it. Surprisingly, there don’t seem to be Chinese knock-off versions of it (yet?) It’s specifically made for saws with short bars up to 20″, which means this is the one to use with a battery chainsaw. By clamping to the bar in just one place, it’s a little less stable, but you get much more of your bar as usable cutting length.

Type 3: Vertical Granberg “Edging” Rig (G555B)

This Granberg unit costs around $125-$200, again depending on shipping and where it’s purchased. There are a few Chinese knockoffs on Amazon from $75-$100, but they have very poor reviews. To use this mill, you lock the saw at a fixed angle (nearly vertical) and push it thru the log, along a metal track:

As the name implies, Granberg suggests you use this to cut the edges off logs to make beams, not to cut slabs, altho with patience you totally could cut boards this way. Many online videos show real people successfully milling with this rig.

Type 4: The Cheap Vertical Rigs

Some say the original mill of this type was the “Haddon Lumbermaker”, others claim it was a Canadian “Quadra Beam Machine”. Regardless of origin, amazon.com is now full of dozens of nearly-identical models, all from China, and all with significant quality and usability issues. A typical unit looks like this:

This is super simple, the rig slides down a 2×4 or 2×6, the clamp holds your bar for vertical milling, while allowing it to rotate, as you pull it down the log. They are very affordable, typically $30 but can range from $22-$38. The Chinese brand names range from generic to comical (ZeroPone, Kweetle, HVUE, Wood-CNL, YEFA, TTF, TAUSOM, AGS, SurmountWay, Farmertec, Zchoutrade, TimberTuff). I was initially attracted to them based on simplicity and low cost, so I spent some hours trying to figure out if one was higher quality than the rest? Ultimately I had to conclude: no, they are all bad. Even if you get a unit without obvious manufacturing defects, you have issues:

• The metal guide inevitably has some “wiggle room” on the 2×4, so your bar will wobble and cuts won’t be straight.
• Getting your bar precisely perpendicular to the rig (to cut at a right angle, i.e. square) can be a real challenge.
• Clamping the guide to your bar is likely to be either too loose (saw vibration will shake it loose and destroy your chain) or too tight (which will either shred your bolt threads, or even snap the cast metal). The solution many people arrive at is using stronger bolts and drilling a hole through your chainsaw’s bar (!)

There are YouTube videos showing unfortunate people using these rigs to produce rough, uneven boards with considerable difficulty. There are some people that claim it works “just fine” for them. There is even one fellow who, through luck, skill and determination, manages to mill slabs of hard Hawaiian trees using one of these rigs and a small, low-power Ryobi 14″ battery chainsaw. So, it can work.

A note on chains

Most people recommend using a special “ripping” chain for cutting down the length of any log. There are even some amazing videos of hard-core chainsaw guys evaluating different kinds of chains for milling, for their effect on cutting time, smoothness of resulting cuts, and how frequently you have to sharpen. It’s a potentially deep subject, but “use a ripping chain” is probably good enough advice for most of us.

Beams vs. Slabs

Videos like this one (https://youtu.be/zw_hq_yJX-Y) show that cutting slabs with a vertical mill is possible but fussy, difficult, and error-prone – it involves a lot of fudging and shimming and tuning your rig to try to keep your log stable and your cut perpendicular. The vertical mills seem just fine, however, for just cutting off 4 sides to make a beam. So, for those of us who want nice slabs, not just beams, it’s an argument for spending the $200 for the type 2 (Granberg G777), not the types 3 or 4.

Conclusion

Based on everything I’ve learned, I wouldn’t get one of the cheapest rigs. The type 1 is too large, but either the type 2 or 3 (Granberg G777 or G555B) seem worth the investment – or both, because edging before slabbing is potentially better/easier than attempting to do all cuts vertically (or all horizontally, then needing to clean up each slab later with a track saw).