About

mill
Mobile Sawmill in action

For the Layman

Mobile sawmilling, on site sawmilling or portable sawmilling all mean the same thing, and that is taking the sawmilling operation to the tree or trees either still standing or previously cut down. I like the tree to be left in full length with only the top of the tree with all the limbs (known as the head) cut and removed (if required) to leave a cut end of 300mm minimum being if the tree has been pushed over by an excavator or dozer to remove the stump (known as the butt) then this will be cut and removed as well.

The whole process is called “Heading and Butting” the log leaving a “mill log “if neither the head or butt need to be removed then we can cut both prior to milling. I like logs to be left full length so as I can asses the best part of the log for the size and length of timber I intend to cut.

This will largely increase recovery. (This is the amount sawn timber cut from a round log.) If these logs are from 300mm to 500mm in diameter I like to leave them dry for 2 months but can be left for 12 months if need be. This process will relieve some of the tension in the log, which will result in straighter timber.

On Farm Sawmilling

Has been operated by Alan for 20yrs. Both I and my partner Melissa supply an on site sawmilling service and a sawn timber supply.

The machinery used is a 3 blade circular saw. The main blade and bottom edger blade are fixed with the top edger blade adjustable, this makes the mill cut an accurate board the full length of the board. This is important as the tension in most of the hardwood species in Australia is substantial as logs will bow and even twist during the milling process, which can result in timber that has been cut being distorted and inaccurate.

This can cost the owner in two ways in particular:

  1. The builder or owner spends extra hours and expense planning or re-sawing the timber
  2. The builder or owner throws away the piece of timber and says ‘’ I’m not using that rubbish’’.

On the other hand if the owner only needs fencing or landscaping timber then distortion or inaccuracy doesn’t matter.

Knowing Your Sawmiller

It has taken me many years to learn and understand the art of mobile sawmilling, after 17yrs I by no means claim to have mastered it. I am constantly being surprised by the uncharacteristic behavior of some logs I have cut. 10 years it took of cutting countless m3 (cubic metres) of timber before I started to understanding the most important principles of mobile sawmilling and producing good quality timber.

To pull the rig in front of a pile of logs in most cases in a paddock; in a lot of cases in town or in a main street or a cul-de-sac and once in the quarantine area in the port of Brisbane. I am usually handed a timber list to cut out of the pile.

  • What size and length of log suits what size and length timber?
  • What species suits what part of the order?

These are all very important questions that will govern the quality and quantity of timber you be left with at the end of the job. An experienced saw miller will know instinctively.

Recovery

It’s ok to say “I get a high recovery from a log “but I feel it is more important to recover as much timber the owner can use in their project as possible.

For instance if at the end of cutting a log I have 10 /150*50 @ 3 metres long where my competitor has 7/150*50 @ 3metres long & 25 /50*25 @ 3 metres long, which is a higher recovery but if 50*25 is not on the list, then there is less off the actual list.

Now some will say I can use 50*25 but if the owner is left short 3 lengths of 150*50 @ 3metres long and he has to buy it then the price per m3 will be double that of 50*25 per m3 if he had to buy it (m3 is a volume of timber that is 1metre by 1metre by 1metre long).

So even though my competitor got a better recovery he cost the owner more money and time.

At the end of the day Mobile Sawmilling is about saving the customers as much money and producing as good a quality timber as possible. Achieving this will see more people making use of logs that would otherwise be dumped or burnt .

In my opinion there are 5 main advantages my mill has over my competitors, particularly when it comes to recovery, these are:

  1. 3 blades: which insures the timber can be used straight away no need for planning or resizing, also reduces the time needed to cut a log.
  2. Diagonal adjusting: logs are rarely straight even when they are the log will taper, (big at the butt smaller at the head) to reduce angle of grain (which reduces the strength of the board if cut diagonal across the grain) timber has to be cut with the grain to obtain maximum “stress grade”.
  3. The clamping system: this is the device used to hold the log in position, spring loaded means if the log moves while cutting the spring will push the pikes into the log further. When you compare this system to the spiking or nailing the log to another it is easy to see witch is the quickest and safest system. This system also allows me to recover timber from the flitch (part of the log left in the clamps).
  4. Mechanical feed: this mill can pass through the log under its own power, cutting three sides of the individual piece of timber at the same time then returning the board to the operator. Compare this to pushing the mill through the log cutting one side at a time. This benefits the owner by the miller exerting less energy staying fresh longer meaning more presence of mind to recover as much timber as possible.
  5. 20yrs experience full time mobile sawmilling.