Quarter sawing an oak log

[ucoulddoit]

Thought others might be interested to hear about quarter sawing an oak log last week using two Alaskan mills and a bandsaw mill. The milled timber will be for my own and a friend's use for furniture making once seasoned and my aim was to maximise the yield of book matched ray flecked heartwood boards. Didn’t realise until recently that although quarter sawn boards can have the growth rings between 90 degrees down to 45 degrees. Ray flecked boards, a feature of arts and crafts style furniture, need growth rings between 90 degrees down to 75 degrees.

 

For the past couple of years I’d been looking for an oak log nearby, at least 30 inches diameter, about 10 feet long and straight, suitable for quarter sawing. Recently I heard of one being felled a few minutes walk from home! Tree was still living, but at the top of a steep bank and leaning over a drive way and adjacent house. So it needed to be felled. Concerned about nails in a garden tree. Also, unsure if it grew at an angle, i.e. might be reaction wood, or if the top of the bank had started to give way in recent years and it was vertical for most of it’s life, so no reaction wood? Also, a visible scar 18 feet up where a large branch had snapped off raised the risk of heart rot? Lots of reasons to dismiss it as a firewood log, but decided to mill it.

 

The bottom 18 feet from ground level to the scar was felled in one length, at my request, It tapered from 40 inches to just over 2 feet diameter, DBH about 34 inches. Cut it into two 9 foot lengths as too heavy to move in one piece and it was lying at a step angle on the bank so not suitable for chainsaw milling where it landed after felling. Bottom section tapered from 40 inches to 30 inches, and once felled and cut to length I could see the pith was reasonably centred and no obvious defects from old branches or rot. Looked ideal!

 

 

The local sawmill (only 2 miles from home) were happy for me to do some chainsaw milling at their yard, a few preparatory cuts, before final milling on their bandsaw. The bottom, largest section will be quarter sawn. Took a while to work out the best sequence of milling and after several options, the attached sketch is working so far. The chainsaw milled cuts, now completed, are bold lines, and the bandsaw cuts, still to be done, are the thin lines.

 

 TH quarter saw milling.pdf

 

Started by rolling the log using a farm jack, so a large shake was vertical, more or less aligned with one of the proposed chainsaw cuts Then freehand trimmed the flare on both sides using a chainsaw so my Alaskan mill would fit. Then trimmed the bottom end flat and square, followed by drawing vertical, horizontal and diagonal guidelines on both ends, all meeting at the pith. Then painted both ends with 2 coats PVA.

 

 

 

 

Top slab, mostly sapwood, was removed with my Alaskan mill to create a flat straight face, parallel to the pith.

 

 

Then the log was milled full width through the pith.

 

 

My Alaskan mill started as a small log mill with an MS171 (14 inch bar) bought years ago. Then upgraded it to an MS391 with 20 inch bar for milling, and about 10 years ago changed it into a 24inch mill using additional parts plus an MS661. This log was a good excuse to buy longer 48 inch rails, a 42 inch bar and two full skip rip chains, all from Chainsawbars. So I can now mill up to 36 inches width. Amazed how quickly the MS661 cut this average 32inch width of oak with the new set up.

 

The top slab was raised onto wood blocks, then cut in half along the vertical guideline, again following the pith, using my Alaskan mini mill with the depth set so that it didn’t cut into the bottom section.

 

 

Some lovely ray flecked figure on this cut!

 

 

After rolling off the two halves of the top slab, the bottom slab was halved using the mini mill. One edge of each quarter was then freehand trimmed the full length with a chainsaw, parallel to the diagonal guidelines, so they will sit flat on the bandsaw bed with the pith parallel to the bed.

 

 

So, that’s the log quartered and ready for bandsaw milling into 30mm and 40mm planks. Based on the 90 to 75 degree limits, might get as many as 16 ray flecked boards, i.e. four matched boards from each quarter. I’ll keep my fingers crossed.

 

Quite time consuming and all done alone without lifting gear which was hard going for an ‘old age pensioner’.

 

 

 

The quarters have been pressure washed to remove moss, soil and maybe stones. Planning the band sawing in a week or so. Just need to make a ply board with 45 degree blocks to support the quarters for horizontal cuts. In the meantime the quarters are covered to keep the sun off and minimize the risk of surface checking.

 

Will post more pictures in due course.

 

Andrew

[Malus]

Looks like you're gonna get a good amount of nice timber out of those logs.

 

When I've quarter sawn large logs I've found a different pattern to be more efficient. I'm not sure it results in more true quarter sawn boards but it's certainly quicker and less hassle for me. 

 

I've done a quick sketch but only have a small scrap of paper and a pencil on me so hopefully you can see it. 

 

Cuts 1 and 2 depends on the extent of the pith and any check, and a multiple of target board thickness.

 

Then cuts 3 and 4 box out the heart and can either form a post or make firewood. In each "semi circle" shaped can't I tend to cut a rift cut post from each corner and then boards which are pretty well quarter sawn. The boards cut from the remainder two sections are also good quarter sawn.  A few of the boards will end up quarter sawn towards the pith and rift sawn towards the bark side. Speaking in terms of how a woodworker would look at the boards, not a true quarter sawn process.

 

Looking forward to seeing pictures of the boards you end up with.

 

[trigger_andy]

Obviously if you saw the log with a bandsaw and box the heart in you'll end up with three slabs that are quarter sawn and then some rift sawn either side of this then the upper and lower slabs will be plain sawn. 

 

If you're getting a lot of oak passing through this is by far the best option timewise.