Holzfforma/Huztl Alaskan Chainsaw Mill Review (with Huztl MS660)

A light, effective and very cheap chainsaw mill can be made from the Holzfforma Alaskan chainsaw mill and the Huztl MS660 chainsaw, but it does need some bush engineering to work well. The mill needed some adjusting to work properly, the Holzfforma bar didn’t last long and needed replacing, and there's a few things to look out for in the MS660, but overall it is a low-cost mill that can do the job. 

The Huztl MS660, the Holzfforma Alaskan mill, and a stack of beautiful silky oak boards

I’ve done a lot of chainsaw milling since I started in the mid-1980s. I’ve used a genuine Granberg Alaskan mill, 48”, with .404 chain. I drove this with a Sachs Dolmar 120cc chainsaw for many years, now I use a Stihl 090 as the mill motor. I’ve milled many tons of wood with this setup. It’s been very reliable, but it’s big: it is very heavy to carry and use and was relatively expensive to set up. 

Recently I set up a new, low cost, lightweight mill for myself, entirely made of Chinese Huztl components. I bought a Huztl MS660 kit and assembled the saw (a friend and I made an MS660 each in one day), adding a 25” Holzfforma bar from Huztl, and a Huztl chain. I bought the Holzfforma 24” Alaskan chainsaw mill, also from Huztl, and made a range of modifications to it, some to correct manufacturing faults, but mostly to make it easier to use. 

The motor: Huztl MS660 kit

Here's my freshly assembled Huztl MS660

This was astonishingly cheap (just over AU$300 on sale), was easy and fun to assemble, and works really well.  

There is a lot of information on youtube about making these MS660 clone saws, and their various issues. One of the best sources is afleetcommand’s videos . My experiences with building Huztl/Farmertec chainsaws, including the MS660s, is mostly documented in my post on building a Huztl/Farmertec MS360. 

I’ve remained genuinely non-genuine: I haven’t added any real Stihl parts to my MS660s or MS360. Many kit builders replace some components with genuine Stihl parts:  

• Afleetcommand points out a problem with some Huztl MS660s, including mine, with the half throttle setting not working properly. When I need half throttle (mostly in cold starts after turning off the choke) I simply use the traditional solution of putting my boot in the rear handle and pushing the throttle up with the top of my boot - a good trick for a flooded saw too.
• Quite a few kit builders report piston and cylinder damage from piston pin clips. My Huztl MS360 post outlines my response, modifying the Huztl clips. 2022 update: I recently helped a friend build a Farmertec 066 kit, whose piston pin clips had no tails at all, so it appears Farmertec is fixing that problem.
  
• Decompression valves routinely lose their plastic heads (all mine have). You can buy a genuine valve, or make a simple fix (also in my MS360 post).
• I've had one bad Huztl carby, but this was willing replaced by the supplier. 
• I've had some trouble with Huztl oil pumps, but each time it's been repairable - see below. 

The MS660 has a 92cc engine which is powerful enough for the 24” Alaskan mill, especially for smaller logs. It would be worth having a bigger saw if you were consistently milling over about 450mm diameter, but that would be balanced against the much greater expense of the motor and the increased kerf of .404 chain used by bigger saws. For most people’s needs the MS660 makes a fine mill. 

MS660 oiler

In the first few hours of milling, I was a bit concerned about the low use of bar oil by the MS660. I’m particularly sensitive to my bar oiling, as I use used cooking oil for bar lube (see my post here on using vegetable oil for bar lube)  and I want to make sure I use plenty, to compensate for possible quality problems with the oil (not that I’m convinced it’s any worse than other oils). Milling hardwoods is particularly hard on chainsaw bars. 

After joining the facebook "Huztl Farmertec Chainsaw Builders" group, I found some illuminating discussion of MS660 oil pumps, and dismantled mine to see if I could improve it. 

What I found was that the pump piston stroke was inhibited by the end pin of the piston control bolt. To increase the oil flow, I tried grinding the end pin right off the control bolt. This enabled singificantly greater oil flow, but disabled the ability to turn down the oil flow. 
I could have achieved the same result with a less dramatic modification, by simply grinding a flat on the end pin in the right place. 

Here's the MS660 oil pump piston (top) and control bolt below. If you look carefully, you can see a gap between the ramp on the piston (to the right of the gear) and the control bolt, caused by the pin on the end of the control bolt.  

Here's the control bolt

And here's the control bolt with the end ground off. 

I later dismantled my earlier Farmertec MS660 saw, and found its pump didn't have this problem, so I left it unmodified. 

The bar

I bought a Holzfforma 25” bar from Huztl (3/8” x 1.6mm, 84 drive links). Outside the Alaskan mill, this has a maximum cut of 610mm (24”) with the saw spikes removed. With the spikes on the saw it will cut about 570mm (about 22.5”) (this labelling of saws with lengths they can’t actually cut is common to various brands including Stihl, not just Holzfforma). In an Alaskan mill, a 25” bar will cut up to about 465mm (18”) wide boards - this is plenty for many trees. 

If you want to use the full capacity of the 24” Alaskan mill, I recommend a 28” or longer bar. Depending on the spot welds in the roller nose, you may be able to drill the bar as I describe below. 

My friend and I both bought 25” Holzfforma bars with our MS660 kits, and both failed very early. Bad steel quality has caused failure of the rails, mostly near the nose. 

See the chip broken off the 25" bar nose? It's where the chain hits the bar rails after coming off the sprocket. The heat mark in the middle is where the Alaskan mill bar clamp squeezed it a bit when I was trying different positions. 

I give a more comprehensive review of Holzfforma bars in my blog post here .

I’ve bought a 28” Tsumura bar from chainsawspares.com.au, which has worked without any problems at all. 

The mill

Here's the shipping box for the Holzfforma Alaskan mill. The serving suggestion shows an 070 motor, which is 105cc and uses .404" chain. 

The maximum width of cut in the 24” Holzfforma Alaskan mill is 540mm (just over 21”), which covers most logs. This requires a 28” or longer bar. A longer mill is good when you have a big log, but it is a nuisance to carry around the longer frame when you’re milling smaller logs. I’m finding it very convenient to have this smaller mill. 

The quality of the Holzfforma Alaskan mill is okay, but (like many things from Huztl) it needs some work before it is ready to use. 

Squaring the cast aluminium bridges

The mill has 2 cast aluminium bridges that join the 2 fence rails to the bar posts. These (in my mill at least) were out of square, so they sprang a bend in the chainsaw bar when I first assembled the mill, and made adjustment of slab thickness difficult. 

Looking along the bar now, it is straight, but this was bent before filing the bridges. 

You can see the mill post (vertical steel piece which clamps onto the bar at bottom) is not parallel to the square

Here's one of the mill fence bridges in the vice, ready to filed square with the dreadnought file. These files are specially designed for aluminium and work very well

The remedy is simple: file the landings where the fence rails meet the bridge, so they’re square to the post. A dreadnought file is the best tool for filing aluminium (should be in every bush engineer’s toolbox) because it doesn’t clog, but if you don’t have one, you can get away with your coarsest file and frequent cleaning of the teeth. 

Filing the landing on the fence bridge

A freshly filed landing

This is how I checked the landings for square while I was filing them. A piece of pipe is clamped where the mill post goes, and a square is clamped onto the landing where the fence rail goes. You can see they're not parallel yet. 

Adding a bridging rail

Alaskan mills usually have 1 or 2 bridging rails, that go between the long fence rails, and are flush with the fence’s bottom surface. These are very helpful when starting and finishing cuts, making it easier to start a cut parallel to the previous cut, and reducing the tendency for the leading fence rail to fall off the end of the log and curve the cut downwards at the end of the cut. The 24” mill only has 1 bridging rail, so I made another one from wood and attached it to the cast aluminium bridge at the engine end of the mill. 

The extra bridging rail is painted green, and helps start and finish cuts

Frame bolt failures

Here's the junction between the mill bridge and the mill rail, with failed bolts and nuts on top. See how shallow the nyloc nut is, and see the stripped section halfway along the thread of the coach bolt in the middle. 

I had an early failure of the bolts that were provided with the mill to hold the bridges onto the rails. These are metric 8mm (M8) coach bolts: they have a domed head with a square base, instead of a hex head. 

The bolts on the outer bridge (furthest from the motor) stripped after a few hours use. This appears to be because the nyloc nuts provided have a very short metal thread, and my need to loosen and tighten these bolts, in order to use different length bars, quickly stressed and stripped the bolt threads. 

These bolts have their heads in the slot of the mill rails, so need to be keyed into the slot - using the square base of the coach bolt - to stop the bolt from spinning when the nut is tightened (you can't put a spanner on the bolt head). Although I didn’t have any M8 coach bolts in stock, I was able to easily replace the bolts with hex head bolts with filed rebates under the head, which key into the mill rail slot. 

Here's the M8 bolt replacing the failed coach bolts. See the rebates filed on each side of the hex head, to key into the rail slot and stop the bolt from spinning when you tighten the nut. I used standard nuts to replace the poor-quality nyloc nuts.

Drilling and direct bolting the chainsaw bar

I’ve done hundreds of hours of chainsaw milling before getting this setup, and I’ve learnt to keep checking and tightening all the bolts in the mill: they tend to vibrate loose. When the bolts that clamp the chainsaw bar to the mill posts come loose, your bar slips and the saw cuts into the clamping bolts. I’ve done this, it feels bad. 

The solution I’ve come up with, and which I’ve been happy with for years, is to drill holes in the chainsaw bar, drill and thread the landings at the bottoms of the 2 mill bar posts, and bolt the bar directly on to the mill. This gives a more positive connection of the bar to the mill posts. Now that you are not depending on friction to hold the bar, less will go wrong if the bolt comes loose. This method also makes attaching and detaching the saw from the mill - for sharpening or other servicing - quicker and easier. 

This is a bar that has been drilled and bolted onto the mill posts. You can see a centre bolt in the left side clamp, and a bolt going thru the roller nose on the right

Here is the bottom clamp piece from the engine-end of the bar, with a 10mm hole drilled thru the centre and a bolt ready to go thru the hole in the chainsaw bar. See the M8 bolt at top, which keeps the bottom clamp in alignment. 

An M10 threaded hole has been made in the middle of the landing at the bottom of the mill post

Here is the bar bolted on with the M10 bolt at the motor end. Both skids are kept in place to run along the side of the log. The M8 bolt on the top end of the clamp is there to stop the bottom skid from turning, but is only bolted to the bottom clamp/skid. 

At the bar nose, only the M10 bolt is needed to hold the bar on

Sometimes it’s hard to find a place to drill some bars around the sprocket nose, so you need to use the clamp. One engine-end bolt still makes for a quick and positive connection, which won’t slide if it loosens. 

I use M10 bolts for this job, and an M10 tap for the mill posts. 

The saw and mill ready to cut

Saw chains

Special chains are available for ripping (cutting along the grain), which is what you are doing when milling. For example, skip tooth chains have fewer teeth, achieved by having 2 blank links between the teeth instead of the usual 1. Having fewer teeth in the cut gives more horsepower per tooth, which allows teeth to dig deeper and cut chips instead of dust, making the cutting action more efficient and the teeth stay sharp longer. 

Chains can also be bought that have been sharpened specially for ripping: filed at 10 degrees from square, instead of 30 or 35 degrees which is normal for cross cutting.  

For milling I usually make my chains from standard crosscutting chain: this means I only have to buy one type of chain for crosscutting and ripping (I use semi-chisel chain, as the teeth cope better with dirty conditions). However I modify the chains as I sharpen them to make them better for ripping: gradually changing the sharpening angle to 10 degrees from square. 
I also often do a more dramatic modification, following the Granberg ripping chain model: grinding the top plates off 1/2 of the teeth in a regular pattern. 

(It's hard to photograph chain teeth) Here are 2 teeth with their tops ground back. The tooth is still full height, but the top plate has been ground back so the tooth is very narrow at the top. 

And here are the next 2 teeth, normal size. As this chain is sharpened, I will make the teeth more square. 

This achieves a similar effect to skip tooth chain, reducing the cutting load of some teeth so that there is more horsepower per full tooth. 

For this mill, I bought 3/8” chains from Huztl to match the 25” bar. The Huztl chains seem quite good (I have written a review of Huztl chains here). I’m sure they’re not as good as Stihl (they’re certainly softer to file), but they keep their edge surprisingly well. I have found a few chains where there are hard spots in the base of the gullet that blunt the file - hard spots are usually caused by sharpening teeth with a grinder, and grinding too hard so a spot of steel briefly becomes red hot and quenches hard. A few sharpenings with a little grinding sharpener should get past the hard spots. 

The mill guide ladder

The mill guide ladder spiked onto the log, with the saw ready to start and cut. Note how the weight of the engine tends to tilt the mill

Alaskan mills need something to guide the saw in a flat plane for the first cut. This is usually based on a ladder or something that looks like a ladder, fixed to the top of the log. 

The saw ready to make the first cut in this log. The ladder has been offset so that the force of the teeth cutting is borne by the mill skids against the log, and the ladder doesn't have to bear the force. The fence has been adjusted high enough so there's no risk of cutting into the spikes (I've done that too...)

For years I’ve used a 4-rung “ladder” I made for the job. It has steel rungs or bridges that span between 2 pieces of very straight timber, dressed from 75mm x 50mm hardwood. The rungs are about 315mm long, made of 25mm solid square section steel, with flat bar pieces welded onto the ends for bolting onto the rails. 8mm vertical holes are drilled thru the rungs at 25mm centres to take spikes that fix the ladder to the log. The spikes are locked into the vertical holes with M8 bolts, which thread into horizontal holes in the rungs. 

Here is one of my steel rungs: the spikes can be put into the vertical holes and knocked into the log with the back of an axe. Then the horizontal bolts are tightened to grip the spikes. The ladder must be checked for twist and adjusted flat.

The rungs are about 450mm from each end of the ladder, leaving the ladder overhanging the ends of the log enough to hold the mill up before the cut starts. 
After the half-round flitch is sawn off the top of the log, I use a barking bar (a small, specialised crowbar for removing bark from logs) to lever the spikes out of the log while they're still clamped into the ladder, by levering up on the steel bridges. The ladder is then removed and the half-round flitch is slid off the log and out of the way. Now you have a log with a flat top. 
To mill slabs and boards, the mill fence is now adjusted closer to the bar, to mill whatever thickness you want. 
Sometimes I put the ladder back on top of the log when it has a flat top, if I've made some bad cuts and I want the ladder to help straighten the cuts. 

What you need

If you are considering setting up an Alaskan mill similar to mine, this is the minimum you’d need:

• Huztl MS660 chainsaw (smaller saws, maybe down to 70cc, would work in small, softwood logs, but the bigger saw will work better, and probably last longer)
• Holzfforma 24” Alaskan chainsaw mill (if you go bigger than 24”, you probably need a bigger-engined saw)
• A good quality chainsaw bar up to about 28” (don’t try Holzfforma, I’ve done that for you)
• Chainsaw chains (it’s good to get 3 at a time, wear them out together, then replace the sprocket and 3 chains together)
• Milling ladder with spikes or screws to attach it (people improvise all sorts of ladders, but you want it to be strong and steady so the first cut is straight)
• Some thin wedges (to put in the kerf behind the saw, when you get close to the end of the cut)
• A cant hook to roll the logs (a crow bar might substitute, but it’s far inferior). Here's my post on how to make a cant hook. 
• A crow bar (useful for lifting and sliding logs and slabs)

Here's a centre board from a silky oak log. See the very centre of the log (called the heart or pith) is within the board (look at the rings on the end grain). This heart needs to be cut thru, or even "boxed out" (cut out in a section of timber and discarded) to avoid drying stresses from damaging the timber around it.

See the short split at the near end of the board, caused by growth stresses in the log. With fast-grown Eucalyptus wood (this isn't), there is much more growth stress, the centre board can split itself in 2 while you mill it. I'll often rip down the centre of a Eucalyptus log with a circular saw cutting the centre slab in 2 before I mill it off the log.

The board has been re-sawn with a hand-held circular saw (1200w Makita) with 8 teeth (a 20 tooth blade with most of the teeth cut off to increase horsepower per tooth - very effective). The board has been sawn down the pith to reduce immediate splits from growth stress, and long term splitting and distortions from drying stresses. The sapwood has been sawn off as it would be eaten by lyctus borers (unless the sapwood was soaked in borax solution).  

Thoughts on Alaskan chainsaw milling

In many ways, Alaskan mills are a terrible way to cut wood: they’re slow, noisy, vibratey, smokey, take lots of time to maintain, waste a lot of wood as sawdust, etc.. However, we use them because they can do what no other technology can do: for a few hundred dollars, and some time setting up, we can mill almost any log, any place. With these mills you don’t need a bulldozer or tractor to snig your logs to a mobile mill, or a truck to haul them to a stationary mill. All you need is the chainsaw and mill, a cant hook, and probably a hand-held circular saw for resawing (it’s very helpful to have a second chainsaw to hand as well, for crosscutting.) They make it worthwhile milling small amounts of timber that wouldn’t justify bringing in a mobile mill. 

For me, although I have a big bandsaw mill, and access to friends’ Lucas mills - both far more efficient and fast ways to mill logs - my chainsaw mills are extremely useful.

Years ago, I had a tiny, 800cc Suzuki four wheel drive with roof racks. I could take my chainsaw mill anywhere this little car could get to, and mill almost any log. 
Chainsaw milling does use a lot of petrol per cubic metre of wood sawn, as the chainsaw engine and the chainsaw cutting process are not particularly efficient. However overall I think this is an energy-efficient method of milling wood in the circumstances it's used in. The massive energy cost of tractor snigging and loading, truck transport, etc., are avoided just at the start of the process. Then if you use the wood at home (as most chainsaw millers do), you avoid another whole set of energy costs in processing, retailing and delivering. 

You still need to know about wood

The setup I’m describing in this post is so cheap, it puts milling within the reach of many people. However whatever saw you use to cut up logs, you still need to understand wood, cut it to deal with its growth and drying stresses, know how to protect it from insects, have space to store it straight and dry; so that you end up with wood you can use, and not a pile of expensive firewood (I’ve done that, it doesn’t feel good). I’ll write more on that later. 

Freehand milling

There is another way to mill wood which is cheap and accessible. A chainsaw can be used "freehand", cutting along a chalk line, to make beams and posts. I've milled many beams this way for houses and sheds. 

Here is the basic kit needed to cut beams freehand. The cant hook and crow bar are used to position the log on vee cradles (short pieces of log with vee notches cut in). The spirit level and builder's square are used to mark the ends of the log with the sections to be cut. The chalk line is used to mark along the length of the log. The small chainsaw is used to make a marking cut along the chalk line, and the big chainsaw is used to rip the log. The axe and adze are sometimes used to cut the sapwood off the beam.

The log has been cut twice to leave a centre slab and 2 flitches (on right), then has been turned and is now being ripped thru the heart into 2 beams. This fast-grown flooded gum has a lot of growth tension that is released in this cut and is bending the beams. Often this bend is pulled straight in the building structure, by placing beams with opposing bends, and using threaded rod to pull them both straight. 

I usually work backwards when freehand milling, but some tropical village chainsaw timber millers use a very different technique to great effect, working forwards along the log. Here's an example of freehand milling with an old Stihl 070:
https://www.youtube.com/watch?v=44i9AMphxrE&t=118s
Here's a Russian with a small chainsaw using a similar technique on soft pine wood:
https://www.youtube.com/watch?v=8qz64ELkxdA
I'll write more on freehand milling beams later.