milling structural posts.

[jamesd]

Whats the best way to mill oak to get the maximum strength out of the wood? I intend to use some of my milled wood for building work on my house etc..

Would you use posts where the central core of the tree runs right through the post? or quarter sawn so you avoid to much splitting from the core?

[agg221]

Core through the centre, which is called boxed heart.

 

However, consult with your engineer before you start milling. Not much point in making 8"x8" if he then tells you it needs to be 9"x9". Also, if you tell him it will be boxed heart then he will use this in his calculations.

 

However, for thinner sections such as joists, rafters etc. which tend to be deeper than wide, quarter-sawn will be less prone to move.

 

Alec

[Copford sawmill sussex]

Core through the centre, which is called boxed heart.

 

However, consult with your engineer before you start milling. Not much point in making 8"x8" if he then tells you it needs to be 9"x9". Also, if you tell him it will be boxed heart then he will use this in his calculations.

 

However, for thinner sections such as joists, rafters etc. which tend to be deeper than wide, quarter-sawn will be less prone to move.

 

Alec

 

 

Agreed, knot size will also come into the strength etc as well as slope of grain. Look up the TRADA rules on grading for strength. It's obly a visual grading bit should help you

[jamesd]

Core through the centre, which is called boxed heart.

 

However, consult with your engineer before you start milling. Not much point in making 8"x8" if he then tells you it needs to be 9"x9". Also, if you tell him it will be boxed heart then he will use this in his calculations.

 

However, for thinner sections such as joists, rafters etc. which tend to be deeper than wide, quarter-sawn will be less prone to move.

 

Alec

 

Thanks for the reply, I have got a 36" plus diameter oak to mill. I was going to mill it all into posts so is it better just to make one beam from the centre? and use the rest for rails etc?

Would it be better to mill smaller trees to suit the size of posts i need so i get boxed heart each time?

[agg221]

Unless you are short on material, I wouldn't try to make a beam from this one. It will make a great selection of soleplates, joists, rafters etc. Soleplates are a particularly good use as they don't need to be boxed heart and do benefit from being cut from bigger timber as you can get them closer to quartersawn which makes them less prone to curling up and subsequently rolling (the original ones on our house have crept out due to this over the past 500yrs).

 

Alec

[se7enthdevil]

if it's 36" then i'd be tempted to cut it all into nice quartersawn boards myself.

[jamesd]

Unless you are short on material, I wouldn't try to make a beam from this one. It will make a great selection of soleplates, joists, rafters etc. Soleplates are a particularly good use as they don't need to be boxed heart and do benefit from being cut from bigger timber as you can get them closer to quartersawn which makes them less prone to curling up and subsequently rolling (the original ones on our house have crept out due to this over the past 500yrs).

 

Alec

 

Interesting i may go for that then, whats the best way to quarter saw using a chainsaw mill then? I'd be looking at mostly 4x2" i guess may be some 6x2" etc

 

I have already cut a load of beams/posts out of a 36" plus oak tree so they won't be boxed heart would they be ok to be cut down to make joists etc?

 

So if i want to make a load of say 8" beams would it be best to pick out a load of oak trees say only a foot in diameter to make the beams box heart and avoid wasting too much wood?

 

Apologies for all the questions, i don't want to go head long into milling the wood up and then realise its not going to be able to be used for what i want!!

[agg221]

The best way to truly quarter saw is to use a combination of an Alaskan and a mini-mill (you will be needing these anyway to make beams efficiently). Saw into quarters and then take sections off each face in turn.

 

For what you are trying to do, you can afford to take three or so boards full width out of the middle (split the log in half up the middle or minus half a board thickness with the first cut). If you take what's left and mill into slabs which will make sections the other way (ie if you want 6" deep joists take a 6" slab) and then cut these out the other way.

 

A Makita 4" depth cut electric saw is useful. You can cut the wide boards down into the right widths and the 4" deep sections out this way with much less waste. Make sure it comes with a fence. They are fairly cheap on Ebay as they are too heavy for general use.

 

Personally I wouldn't cut down the existing posts - check with your engineer as there will be some sections which are under less loading and they should do this nicely. In future though I would be inclined to use logs just about the right size to get the beam out of the square of the heartwood.

 

One thing to consider is aesthetics. For example, my rafters only need to be 4"x2" but they are exposed and I preferred the appearance of 3" width as it looks more solid.

 

Alec

[jamesd]

The best way to truly quarter saw is to use a combination of an Alaskan and a mini-mill (you will be needing these anyway to make beams efficiently). Saw into quarters and then take sections off each face in turn.

 

For what you are trying to do, you can afford to take three or so boards full width out of the middle (split the log in half up the middle or minus half a board thickness with the first cut). If you take what's left and mill into slabs which will make sections the other way (ie if you want 6" deep joists take a 6" slab) and then cut these out the other way.

 

A Makita 4" depth cut electric saw is useful. You can cut the wide boards down into the right widths and the 4" deep sections out this way with much less waste. Make sure it comes with a fence. They are fairly cheap on Ebay as they are too heavy for general use.

 

Personally I wouldn't cut down the existing posts - check with your engineer as there will be some sections which are under less loading and they should do this nicely. In future though I would be inclined to use logs just about the right size to get the beam out of the square of the heartwood.

 

One thing to consider is aesthetics. For example, my rafters only need to be 4"x2" but they are exposed and I preferred the appearance of 3" width as it looks more solid.

 

Alec

 

Thanks for the help, hows best to store the box heartwood posts as i won't be using it immediately? (I'm a bit worried about them moving a lot) or is it best to use it straight away for building?

I think i will mill everything oversized as it can always be planed down to the correct thickness.