Thread: timber properteys during milling.

they bowed 6" up wile cutting so one finished there is about a 3" bow in the board. i cut them verticly from the log.

we used them as rafters in our carport/shade cover there is a solar system going on the roof so we wanted the bow up so when they sagged down under the weight they would be straight. they all bowed evenly so it causes no problems.

we have 8m 8x2 unsupported open rafters in our house they were cut with the bow in them so under the weight of the roof they straightened. worked fine they are now all straight.

So is that the top position in pic 2?

8m! even in F22 that's 3.1m longer than the span tables allow for in the building code

yep the front of the house is on hardwood poles cut from our property all red Ironbark 11m tall at 5m intervals with red Ironbark log top plates spanning 2 posts.

there were no regulations for the posts and top plates at the time so they were not counted as bracing we had to put threaded rod right up threw the walls.

i will post pics once my camera has charged.

here ya go allan.

Looks great Carl!

Thanks Carl for introducing the information to new millers. I dont care much for how you spell or describe what you are trying to tell us as its the information which is important.

No matter how much knowledge you have those with more or less experience than you will always find fault in what you are trying to tell people which in most cases is a response by them for not understanding what you are trying to explain in the first case.

Easier to take the than ask the stupid question and make yourself look dumb!!!

Remember that your experience is NOT always correct for all millers. It may be on your type mill but things can be totally different when using another milling system which makes explainations difficult for ALL systems. What is explained for a swinger can be totaly wrong for a quartersaw and the miller who knows the quartersaw may understand everthing to do with their mill but will be confused by what you are trying to explain to them. Its all to do with the dynamics of the timber and the way the different sawing techniques and their dynamics react to each other.

I have seen large square posts taken off by swingmills and the timber bend in both directions yet the quatersaw in the next exhibit milling the same timber and size of log will mill the post without and stress bending.

On swingers we tend to react to the stress in the log as the normal milling operation is from the outside in. In large static mills with multiple milling stations in the milling process they tend to mill from the inside out thus recovering better and streighter boards yet when in a hurry and not taking the sapwood off first the boards are no better than bush milling.

In my experience Radial milling produces the most consistant boards no matter what type of milling system you are using. This is because we mill the sapwood off first thereby reducing the pull on the heart by as much as 80%. You still can endup with movement in the boards but not as much by a long way.

The major problem with Radial milling is the need for a log lathe which reduces where you can mill as the stability of the lathe requiers a somewhat level milling area.

Sorry to say this (and please note Carl) that after you have pressed the Submit Post/Reply you can normally expect the critics to reply first to your post!!!! - maybe more stupid questions should be asked?

in my experience a static mill will remove the fletching first leaving a square cant than mill from there.

the first saw to be used in a static mill should be the Canadian.

remove one flitch roll log 180* remove opposite flitch roll 90* remove flits roll 180* remove opposite flitch. by doing opposites the keeps the log straight as there is the same tension on both sides of the log.

the square can is then taken to a breakdown saw where it is cut into whatever stock sizes they are cutting for 6x2 it is cut into 6" cants the width of the log. these are then taken to smaller saw again and cut into 2" strips leaving 6x2s in the end.

the flitches that are removed witch are quite large are then taken to the breakdown saw and trimmed up and cut into things like fence palings and the like.

on very large logs the log will be quaterd on the Canadian tehn cut into 6" strips on the breakdown then sawn into 6" wide strips down to the bark witch is discarded.

the process of constantly changing saws and sawing direction eliminates most of the bow. also the power feed on the mills allow the logs to be "pulled" during milling to get straight boards out of bad logs

Carl or anyone interested

If you would like to get some real experience with milling australian hardwoods in a traditional mill give me a call. Best guess would be 4 weeks of your time so you get experience in all positions in the mill. The mill is near Bellingen. We also have a few other mills in the area who could have their arms bent to help although they may charge for the service.

Pay would be just what the workers get which is $15 to $20 per hour for 37.5 hr week. I have a spare cabin here so accommodation can be supplied.

The workers here really know what they are doing and most have inexcess of 20 years working in these types of mill and milling NSW Forestry plantation timber which has lots of tension.

Offer open to ONLY 2 persons per month any extra will be put on a waiting list.

Must be fit and willing to do long hours and heavy work.

Working there for a few months myself made me appreciate my swinger.

arthur

That sounds great Arthur, I am very interested.
I broke my arm recently, due to that and other commitments I would be keen to do a months work in March or April.
That of course depends on how my arm heals and whether I am ready for manual labour by then.
It also depends on whether I am unfortunate enough to land a job by then too

Cheers, Jack

Jack

I will pensil you in. give me a call on 02 66550967 to discuss

arthur