Big J

That is exactly what I want. Any details would be very much appreciated Rob.

I'd like it to be pretty similar to the Alaskan mill, requiring a flat surface for the first cut. I reckon it would be quicker to set up and more flexible to cut around burrs and the like. Static power pack, chainsaw mill moving up and down the log like the Alaskan mill.

From my point of view, I wouldn't really want to go beyond a 60" bar. That would give me a 52 inch cut, which is frankly enough. Handling of boards becomes a huge PITA. Spec for me would be : 52" throat horizontally, 30" throat vertically if possible (makes is a very useful machine for halving and quartering very large logs to be further sawn on the band mill). Mill could be manually winched through the log so no powered drive required. Approximately 15HP required. Any proposal or even ball park figure would be superb.

Yes. The cone is fine, but the drive shaft sheared. Had to get a new one made which would have been extremely expensive if not for having a tame engineer. My screw splitter runs off a 20hp Briggs and Stratton V-twin. It's belt driven (though only one of the two belts is on as finding the right size tensioning pulling is tricky). It runs very well and splits very quickly in the right wood. It does have it's limitations though and with the amount of power I have available to me, very knotty timber is usually a no go. Moderately knotty timber is OK, but you have to think about the way that you present the round to the cone. Clean timber is a breeze though - I did a couple of cube of Scots pine at the end of a day last week in an hour, which included picking it off the stack, cross cutting it and putting the equipment away after. Jonathan

You can get a bit of band wander if you are trying to push a blunt band on past it's best. I was cutting some fairly hard, dry(ish) Elm a couple of days ago and whilst it was cutting flat, you could hear the motor starting to work harder. Cut rate was also down - in fairness to the band, it had cut 130 cubic foot of 1.25-2 inch stock (sycamore and elm). Took it off, new band on and my labourer couldn't keep up with the boards coming off. On a sharp band you run out of power (38hp) before it will wander. Alec - quite agree, would put you in a class of one with no competition for economically milling 5ft butts. Bella - not sure that much power is necessary! My experience with chainsaw milling is such that cutting speed increases exponentially with power. 8hp isn't twice the cut rate of 4hp, it's more like 5 times. My hope is that 15hp of hydraulic power (huge amounts of torque) will result in 4-5 times the cut rate of my Stihl 088, turning 15 minute cuts (which 18ft of sweet chestnut at 42 inches would be, averaging out the three cuts between sharpenings) into 3-4 minute cuts. Can anyone find a motor and power pack to do that?

My mill (Logmaster LM2) does cut very well and indeed very flat, especially compared to it's predecessor (Woodmizer LT40). A lot has to do with the wider band (2 inch) and the fact that it's thicker too. I'm a big fan of a four post head too. It's a chicken and the egg situation with a purpose build hydraulic chainsaw mill though. It requires a reasonable amount of work ahead of it to justify construction but the work would only be wisely undertaken with a bigger more powerful chainsaw mill!

I paid £2 a hoppus for a couple of large trees in 2012. Lovely stuff, but not that easy to shift. Still, a pleasure to saw, dry and handle and I did make money on it.

The LT35 is not a model that is sold in the UK as far as I'm aware. Have you considered trying to find a second buyer and shipping two over? You'd have no issue getting two into a 40ft container. Jonathan

I do believe that the air was practically at saturation point. In my experience of drying sawn timber in that kiln, the RH never reaches higher than 83%. With the firewood, it sat at that for a couple of weeks, like the sawn timber would, and then started to drop. I took it out at about 65% as it just wasn't worth continuing at 3.5kw/hr. The firewood was mostly very dry, though a bit patchy in places. I've never found there to be a need to have RH meters each side of the stack. Give that the volume of the air inside the kiln is 18CM (accounting for the space the timber takes up), the fan completely circulating the air every 21.6 seconds I think that there would be very little difference between the two. I find having knowledge of internal and external RH far more useful.

Harvester sprocket would do the job I'd think, and you've got up to 16 tooth sprockets, which would gear it up to similar speed as a chainsaw. Harvester Drive Sprockets | Harvester | Clark Engineering I like the very flat cut you get with the chainsaw mill, I can handle the sawdust, but the cut speed and the fumes are awful. I thought that harvester chain might also be better as it's stronger and would be better able to handle the additional horsepower?

Thankyou for the suggestion, but I'm not going to bother with firewood again in it. I just don't think that electricity is the way to go with drying firewood. Fine for sawn timber though.

That is very good value for money Difflock. Makes you wonder why they are twice the price here. They can be a pain with the electric motors, and you will have to order some spares from the States, but it does seem like the best mill for your money so far. I have a friend who runs a weightlifting equipment business that's just opened a warehouse in the US. If you want to go ahead with it, I can speak to him about acting as an intermediary. Jonathan

Bit of quick ebay scouring on my end has concluded that electric is out as motors in the 11-15kw range are just too heavy (best part of 100kg). Hydraulic power pack, 72 inch bar (would need to be bloody rigid though - some sort of bar tensioning system ideally to prevent bar sag) and harvester chain to take the power. Who's up for building a prototype?!

One thing I've always wanted is a purpose built slabbing machine, something along the lines of a chainsaw mill but with a lot more power. Toyed with the idea of an electric motor driving the chain, but then you need a generator for remote work. Alternatively, a hydraulic power pack driving a hydrostatic drive type motor driving the chain. Still tricky though. You could have direct drive from a vertical shaft mower engine, but then that means having all the weight of a large 4 stroke engine going up and down the log. Either way, 8.8hp just isn't enough for a 40-50" cut where 10mm of sawdust is being removed. What are the options? Jonathan

The temperature and RH is measured on the far side of the kiln to the main circulation fan, but before the air has permeated through the stack. It should be noted that the 3000 CM an hour is the circulation fan, not the extraction through the heat exchanger, which is around 200 CM an hour. The reason I couldn't get up to temperature for the firewood is that the heat loss, intended and otherwise, was too high. This is most likely due to lower efficiency in the heat recovery unit than published (as is often the case, however it's still hugely better than having no heat recovery). Winter average temperature is about 5c here and average humidity about 85%. That means incoming moisture of 5.86g per cubic metre (1.172kg an hour). Outgoing varies - the kiln will usually sit at 83% RH for 2 to 3 weeks innitially and then drop 1 to 2% per day thereafter. At 83% and 30 celcius, it's extracting 25.27g per cubic metre (93l per day total extraction, once incoming moisture accounted for). A full kiln has 250 cubic foot (7.1 cubic metres) and at least 3000l of water that needs to be removed if green. Jonathan

Very true. There are some very large old sweet chestnuts in the area. I can think of at least a half dozen trees locally with a DBH of over 5ft, some up to 8ft. Dalkeith Country Park (just south of Edinburgh) has a small stand of perfect form, straight stemmed trees at about 2-2.5ft dbh. 30-50ft of straight stems on them. Up here, the issue seems to be that most sweet chestnuts struggle to grow with good form. You see a fair few on the old estates, but unless it's a fairly sheltered stand with good soil, they suffer badly from ring shake and spiral grain. Jonathan

Wouldn't it be a bit far to haul it from the Arctic? Surely it's an Artic(ulated) load you're after!? Joking aside, Helmdon sawmills near Brackley produce a very large amount of firewood, and at an excellent price too. Perhaps worth giving them a call on 01295 760305. Jonathan

Rob - I think that the Log Pro would be too aggressive for any kind of sawn timber. Too much heat and a very short drying period.

I just couldn't get the temperature up to where it needed to be to shift the water. Consequently, it took far too long and was too expensive. I think air flow is also an issue and I'm not sure how you'd resolve that. The fan I have is pretty powerful (over 3000 cubic metres an hour) and it's ample for sawn timber. Jonathan

The stack of beech there is about 1/20th of my stock and I'm only a small outfit. Timber just takes ages to dry, so you need a big rolling stock!

Don't pay attention to the top stack - it was only there temporarily. You want all stickers and bearers to line up. I mix up the board widths throughout the stack, no real order really. I use 18mm or 22mm stickers. All my stacks are in barns with moderate to good air flow and no direct sunlight. Jonathan

That seems to be the biggest issue. From what I've heard, it's spectacular when cut, but 90% is wasted in drying. It takes a very keen eye to spot logs that are likely to present fewer problems. A spiral grain log wouldn't be a good place to start. Jonathan

Very good advice from Alec (as usual), but just two points I'd add (or perhaps even mildly disagree on!). I stick every 18 inches, religiously. Sometimes that isn't enough and you'll still get movement. Perhaps it's sometimes more than enough, but you can't get a flat board flatter, so I'm happy to take that extra time as an insurance policy. I also reckon it's very important to stick right at the end of every board. It's incredible how much an unsupported board can move, in addition to which it helps reduce end checking. I also don't like log form stacks. The reason is that all the boards above the centre are inclined to cup up, all those below to cup down. There are no oppositional forces and I dislike that. Build big stacks and try to flip the boards around. That way you've lots of oppositional drying stresses pushing in all sorts of different directions and movement is minimised. Have fun! Jonathan

I'm 4 miles from the Forth Road Bridge and there are beds and food for you here. It's a fair old trek on a bike with the correct number of wheels, let alone a unicycle!

It's not to say that they do not produce mills that do not cut good boards, but the issues are many. Firstly, they are too expensive. An LT40 with a few options if £35k. Whilst mine isn't as mobile, it does everything an LT40 does, and most of it better for £21k. Secondly, running them is too expensive - parts are all custom, even the parts that shouldn't be have often been subtly altered so you have to buy everything from WM. My last parts order before I sold my mill was nearly £900. Thirdly, they are so damned fiddly and complicated that you are best advised to use one of the WM reps to service your mill. Until recently, that meant whatever rate the individual mechanic saw fit to charge. Now it all goes through WM UK at £50 an hour, and the reps are contractually bound to only do work through WM. Finally, the set works are a waste of time. No matter how well set up they are, they will not produce boards of even thickness consistently - mine was 'perfectly set up' on it's final service for me, including a new vertical raise/lower chain and it still lost a few millimetres here and there. The best way to get accurate boards is to use a manual scale. If you want 35mm boards, go down in increments of 38mm (3mm for kerf). You cannot go wrong that way. Difflock - there are very few European makers of band mills. There are a few in Germany, Serra and Wimmer to name a couple. They really are the Rolls Royces of bandmills though and are well outside your budget. German Ebay throws up a few, though less than last time I looked. Search for Sagewerk. Regarding the US makers, your budget is such that it puts you at the top end of the manual market and the very bottom of the hydrualic market. Cook saw and Turner are both good makes. I'd advise chatting to both of them. Jonathan