Help with cutting stringy bark

[Jack jr]

G'day I may be cutting a load of timber for someone for a greenhouse,

 Included in the list is 4x4s 13 feet long, these will be cut from stringybark logs, to cut them free of heart and cut the tension out I would need a log 20 inches across, would I be fine to box the heart for them? So I can get them out of smaller logs.

They will be cut on a breast bench.

Cheers Jack jr

[Magicman]

I don't quite understand your question but I will be sawing some 4X4's today.  Depending upon the log, I will probably get 1, 5, 9, 12, etc. from each log with the heart within one 4X4.  

What you actually get will depend upon the log and the orientation of the pith.

[Jack jr]

Cutting  1/4 sawn timber out of stringybark you may need to cut inches of bow out of your timber. Because of the amount of tension in it, meaning you need much bigger logs then if you where sawing them out of something like pine.


I am wondering If it is ok to box the heart of stringybark logs or if they will rot out faster.
Cheers Jack jr 

[beenthere]

Jack jr

Tell us more about what you know about your Tasmania "stringybark", as likely many readers, like myself, know very little. Diameters of the stringybark logs and what you know about the tension wood characteristics of this species (or group of species). 

Might also post a pic or two and info about the "breast bench" you mention. All will be interesting.

Thanks

[longtime lurker]

A 100x100 can't carry an F grade if its boxed heart.

[Jack jr]

here is a picture of the bench and a stringybark log 10 feet long being split with the chainsaw you can see it has opened up a couple of inches.
Jack jr

[Jack jr]

[Magicman]

And the next one that you open up by splitting the pith will do the same thing. 

[Jack jr]

G'day Magicman, I realise that splitting the log will make it bow, it was the way I was told to cut them by an experienced sawmiller, by letting it bow then cutting the belly and horns out of it you end up with tension free timber, I was just wouldering I'f I would get away with boxing the heart for 4x4s but it's sounds like I am better not to include any heart at all. I have been told at best you get 30-50% return from eucalypt logs,How would you break down one of these logs? Thanks for the help.

Cheers Jack jr 

[Magicman]

Note that my comments are pointed toward sawing framing lumber from SYP.  The sawing would be from different faces if I was sawing flat lumber for woodworking, cabinets, etc.

This is the way that I do it:  LINK

This is a long topic and has input from many different sawyers.

[longtime lurker]

Magicman saws mostly SYP (Southern Yellow Pine) for framing. He's located in Mississippi... he'd tell you that's "the south" but yanno that doesn't even make the hemisphere.

Under Australian structural grading rules for hardwood you cannot box heart under 175x175. There's an alternate reading of that rule that could allow a 150x150 boxed heart but it would be best approached with care because it relies on everything going right

What you've done is the traditional way of dealing with a small log with a breast bench. It's traditional because it works. What you might do is put your ripping cut 3 inches off the heart, then break it on the bench to get a 4x4 above the heart and one out of each wing but you need to have near perfect logs for that.

Keeping 100x100 straight with little eucalypt logs is always a challenge. You just have to accept the waste and price it in.