openspaceman

to me it was the little steam driven battery charger made by alco for SOE agents in France

Yes it's alkaline because of the potassium (and some calcium) salts

I have often forked chip out of failed bottom unloaded silos ( curse of the devil) and walking floors without immediately obvious problems. I do get out of breath very easily but at my age... I always had someone keep an eye on me in the silo because of risks of CO or simple low oxygen. From what I understand CO is a problem with very dry wood, people having been killed by it in ships holds. Have you ever sat a logging CO detector on top of your chips?

Yes you have both got the correct reason. There are many mechanisms that make it difficult to achieve a goo turn down ration with a wood burner compared with a gas flame, lower emissivity being one. One can make a fair judgement of the reason for the smoke (which is just products of incomplete combustion) by its colour. Mostly we are probably talking about a mild blue haze and this is generally caused by the secondary flame being quenched before the offgas has been fully oxidised, what has happened is the flame has stripped the easy to burn hydrogen component from the mixture of compounds and the remaining carbon has reformed as a microscopic graphene based soot before it can be oxidised as it has moved beyond the flame into a cooler area, often the cooling will be by excess air or the aforementioned loss by radiation. These tiny particles then form a sol in the exhaust gas and the weak forces that hold them apart act over similar distances to the wavelength of light such that they pass all but the blue component which we see reflected as a blue haze.

Most biomass has about the same calorific value on a dry ash free basis but conifer beats hardwood on weight for weight by about 10% because of the higher lignin content, so given a high ash content and low lignin you are probably right. What we found with willow asrc was the ash has a low fusion temperature and clinker became a problem the short period we tried it.

You beat me to it Ian. If you look at machines harvesting eucalyptus for pulp in warmer climes you may notice they set the knifes to strip most of the bark, which is left to decompose, removing the white wood only means less fertility is exported with the crop.

That's because the bark %age goes up and bark has a higher mineral content.

What colour smoke and what is the flue gas temperature as it leaves the boiler?

Don't you still offer the option of a 12V electric pump in tandem with the engine driven one for this very reason? Nowadays we have to have a crane available for lifting a dead chipper off site on rail work. I have also had a 10 year old track snap where the wires had corroded through cracks in the casing but we were carrying a spare, it was an eye opener as it looked unworn otherwise. Again with another we lost a track in mud on a hillside construction site and had to drag it out with a 360 to work on it, no significant damage to the under gear.

I didn't know he had those, ours is 6" with top roller feed and lister 3 cylinder engine. It has Percy's adaptation to the feed to make it compliant and as far as I can see would cost £60 to monitor engine speed and dump through the same circuit. It too weighs over 750kg which is why the bluechip has lasted so long, only the older blokes can tow it. The older Dosko has been owner operated for the last 15 years which is why that is still going strong but I do question it's productivity compared with a more modern chipper.

I plainly missed those so still need convincing that one can deliver own goods in a vehicle whose gross train weight exceeds 3.5 tonne without a tachograph. As far as I can see the only recent changes to legislation you may be referring to is the removal of the exemption for an operator's licence for a trailer less than 1020kg unladen weight when carrying goods for hire or reward. The exemption from operator's licence remains for most of us delivering our own goods with such a trailer. An exemption from requiring a tachograph to be fitted is a different issue. Well it seemed fairly clear to me, though IANAL people I work with do rely on me for advice on transport related issues, including a recent case I took before the traffic commissioner in the face of opposition from the highways authority, regarding our operating centre, he ruled in our favour. In fact the text accompanying that particular document says: "This form is used at the time of a vehicle test if a HGV does not have a calibrated tachograph fitted and the presenter wants to declare it exempt." but granted it may influence a policeman at a roadside check. So my view remains in the unlikely event you are stopped at a roadside checkpoint whilst delivering logs with a trailer and you are not overloaded or breaking other traffic laws: You do not need an operators licence if the towing vehicle is less than 3.5 tonnes MAM AND the trailer has an unladen weight of less than 1020kg and a MAM of 3500kg AND the logs are your own goods. You do require a tachograph unless the work is agricultural or forestry enterprise. You probably don't require the CPC on top of your B+E licence.

And its offspring the bluechip. I used a Dosko for over 10 years and it's still going but engine parts are becoming a problem. Where I work there's still a working bluechip but both lacking stress control makes them a bit limited on those jobs where you just want to stuff whatever comes in and walk back for more.

I think it must be a job requirement where I do work.

I was told strip a bit of copper flex and run it either side of the ridge, not tried it as moss on roof isn't a big problem here.

Which bit are you quoting from? The document attached in this thread says: "Vehicle with a maximum permissible weight not exceeding 7.5 tonnes which only carries material or equipment for the driver’s use in the course of his work within a 100km radius of the place where the vehicle is normally based, provided that the driving does not constitute the driver’s main activity." To my mind if you are delivering logs from a non agricultural enterprise then you can't use this exemption either because delivering means driving is the main activity or that the goods are not material for use by the driver. I suspect carrying logs is sufficiently agricultural looking not to attract attention.

That's my understanding though chances of getting pulled are low. I can tow a tracked chipper up to 100km on a non agricultural job without the tacho and use the chipper on site but if I deliver it to a job for others to use I should have a tacho. You can test the water if you like, the fine was only £200 when the chap delivering our chipper behind his disco got pulled. I cannot see the difference between this and delivering firewood.

Strength isn't an issue in a stove, corrosion is. Steel will resist oxidation at fairly high temperatures but get it too hot and it burns at the grain boundaries. As cast iron has a much higher carbon content these grain boundaries are occupied by carbides and graphite, which though it is pure carbon is highly resistant to oxidation. You can see this if you first oxyacetylene cut a sheet of mild steel and then try the same with a similar piece of cast iron. I don't know which steel alloys might offer the same corrosion resistance as cast iron but my guess is a steel stove with refractory brick liners will last well and as the combustion temperatures will be higher should be cleaner burning too.

Solar powered kiln kiln is much sexier than polytunnel dried

Basically yes but I cannot put numbers to your other question, in essence smaller logs have more "edge effects" as do smaller containers. As I said this does depend on the size assortment being similar. To illustrate this a bit; consider a sample of woodchip which has sizes assortment ranging from 4% of <1mm to 96% <32mm. Screen out the <1mm sizes but the volume of the remaining >1mm remains the same because the fines you have screened out fited in the spaces between the larger particles.

Many do, it's like they think the thumb along the axis of the handle is exerting some extra control. It has nothing to do with tightness of the grip. The reason for having the handle in the crotch of thumb and forefinger is that any kickback is pushed into the joint and the saw and hand move back together rather than the saw sliding back past the wrist. Most at risk when making a horizontal (falling) cut with the pushing part of the chain.

That's my view too. With split logs it's easier to demonstrate, stare with a ring, split it once and try and put it back together, split it into 4 and try and put it together, each time you split it each new surface has irregularities which increase the gaps between logs.

It needs a bit of empirical evidence but: assuming all the logs are cut to about the same size and there are few smaller logs which will fit in the gaps between the larger logs ( look at aggregate theory especially in things like the size distribution of sand in lime mortar) Start with 2 logs 80" long now, ignoring kerf, cut it in half is there any way you can stack it so that it occupies less space than the original log. Do this for one log in 10 bits and the other in 8. Even if you try and reassemble the log the cut suraces will always mean you take more space. The ultimate test is to chip a solid log, the chips occupy about 2.8 times the solid log, normal cut and split logs occupy about twice the solid volume.

Actually they seem to sharpen ok on a diamond disc, I only get discards and haven't a saw to try them on atm but will soon.

Right on the first two points but I disagree on the third, they'll be getting less solid volume for the same bulk volume.

Thanks spud, that must be one of the attachments from the chainsaw repair forum cut4fun mentioned?? re your previous post, this saw came to me after the fitters so was already in bits with the plug missing. As the rings were stuck and only light scoring on the exhaust side I'm tending to think over revving coupled with lean mix . re Gardenkit's test, I do remember seizing a newish saw by using neat fuel, it was in the days of 4 star before unleaded was available and yes it ran for more than one tank before failing, at the time I put it down to the lead acting as a lubricant.