Thread: timber yield in finished piece of work

At least your calculation is near enough to correct,

Originally Posted by Chesand

At least your calculation is near enough to correct,

Darn, was hoping I was totally wrong.

Now I'm depressed

Yes, I would say your calculations are pretty close alright.
When I was milling with my chainsaw mill, my '404 chain would turn 8mm of timber to sawdust every cut, if I was milling 32mm slabs, that meant 20% of the log would end up as sawdust. Then you would lose the flitches unless you had a use for them, and there was always wastage at the centre of the log, those could account for another 30% loss, so there's your 50% straight up. Then drying would lose a bit more with cracks and any warpage, then thicknessing you would lose more, yes depressing to think about it.

Incredible, I was only discussing this subject with my chemist an hour or so ago as she watched as I signed off the scripts with one of my segmented pens. I said to her that most people do not appreciate the amount of work involved to produce the finished item and the volume of wood actually used to make such a small item.

Wow. Also, do most people factor 50% wastage for typical furniture making? I've never really paid that much attention but always figured about 40% on top for something like a dining table to cover jointing/thicknessing, cutting to length, defects etc. But if it's closer to 100% extra then that would really make it difficult to be profitable if making something to sell.

Cheers, Dom

I have very little offcut waste when producing anything. I would factor in 100mm of waste per rough stick. If the stick is 1000mm long, I've lost 10%. If the stick is 6meters long, well happy days because I've only lost ummm...1.6% sounds about right.

I try to as much as I can. Good machine setups eliminate snipe on most machines. Regular size off cuts are further processed into other products. Even down to using small pieces for jewellery like earrings and brooches. Anything but throwing it in the bin. I do a drink coaster, a bottle opener, my Book Birds, bangles, rings, pendants all from a natural offcut from the production of the stool I make. From a batch of stools, one of the aforesaid products gets made. When I make my Book Birds from figured timbers I make hearts that I either sell finished or unfinished ( there is demand for unfinished, i kid you not), or turn them into pendants, earrings, brooches and jewellery sets. I get quite good money for stuff that most would bin.

I generally have less than 50mm more than I need in terms of length. Take 2 3.5s off that and divide by two. That is my waste. Sounds cocky maybe but snipe can be eliminated on most machines, including lunch box thicknessers.

Don’t throw it away, give it away, use it or sell it. The stuff is just far too valuable.

Well yes, if you are buying dried boards cut and dressed near to the size you need, sure you can minimise your own wastage. But there has been wastage to get that board to you at the milling and drying stages of the process . There is no doubt about that.

None of my off-cuts are wasted...they go into my wood-fired pizza oven to make delicious pizza . That highly-figured, super-dense Australian hardwood sure does burn nice and clean . So 0% waste on the off-cuts haha.

Cheers,

Dom

Let’s just all start building log cabins then, still wastage but possibly the lest amount [emoji16]

Originally Posted by DomAU

Wow. Also, do most people factor 50% wastage for typical furniture making? I've never really paid that much attention but always figured about 40% on top for something like a dining table to cover jointing/thicknessing, cutting to length, defects etc. But if it's closer to 100% extra then that would really make it difficult to be profitable if making something to sell.

Cheers, Dom

Well the thinking there is slightly different. For example, say I want to make a table top 900 x 2000, I'll use 200 mm boards so want 10 metres of 200mm material, so get 5 x 2.4 boards just to be safe, want to ensure the ends are clean, allow for snipe and the like, joint, plane and finally rip cut them to 180 widths each too. Say I use 5 quarter and intend on getting 25 mm final thickness.

The end result is 5x32x200x2400 down to 5x25x180x2000 which is a volume yield of 59%, better than my generalised 50%, but tabletops are probably the at the top end of yield. As for pricing, don't fret, just keep pricing the way you do, but don't tell the world that we woodworkers aren't really saving the planet

By the way, if you talk surface area of the timber, ignoring the thicknessing, this scenario works out to about the 40% you mention Dom.

Originally Posted by Cal

Let’s just all start building log cabins then, still wastage but possibly the lest amount [emoji16]

Bugger, I'm too old and weak to be lifting logs now

Good one Cal

Originally Posted by domau

none of my off-cuts are wasted...they go into my wood-fired pizza oven to make delicious pizza :u. That highly-figured, super-dense australian hardwood sure does burn nice and clean . So 0% waste on the off-cuts haha.

Cheers,

dom

love it

Originally Posted by DomAU

Wow. Also, do most people factor 50% wastage for typical furniture making? I've never really paid that much attention but always figured about 40% on top for something like a dining table to cover jointing/thicknessing, cutting to length, defects etc. But if it's closer to 100% extra then that would really make it difficult to be profitable if making something to sell.

Cheers, Dom

We'll generally order 10% over the total lm needed or, for table tops, +2 full boards to allow for unusable ones.

Waste can be dictated by what the client orders; I've had to make table tops that are specified at 55 or 60mm thick, which means we have to buy 75mm stock and send 25% of it straight into the dust extractor. Same deal for tops finishing at 40mm, buy 50mm and dress 20% off. If we have to cut 3mm solid edging for veneered board we lose over 60%: 4mm for the saw and another 1mm for sanding

It can also be dictated by what our suppliers send us. A common one for us is bed rails that finish at 120mm wide. We order 150mm boards, but what's delivered is anything from 150-200 wide depending on what they have in stock; a 30-50mm offcut is generally usable, anything under that is firewood. Or you might lose 5mm in thickness and 10-20mm in width just straightening a board.