openspaceman

Yes English elm was named ulmus procera, it is now classed as a hybrid or variety of ulmus minor and is sterile. I have collected seeds from the streets of Brighton and successfully grown from them. I must have dropped one on the path beside the house as it keeps growing from the crack betwixt house and concrete path.

Was he the one that peppered someone’s posterior with lead or was that the father?

That by implication answers my question that you use a probe of some sort. I've never owned a moisture meter so use oven drying until I see a comparison I'll not know which basis the moisture meter uses.

How will you check them? One of the things @Woodworks and I have previously discussed is how moisture meters are calibrated and the same holds true for the tables of equilibrium moisture content he cited. Most lumber drying measures moisture on a dry weight basis. I think the recent legalisation for firewood is measured on a wet weight basis?? Now if the example of 21% moisture content being in equilibrium with air at 90%RH is based on moisture as a percentage of dry weight then that equates to 17.4% wet weight basis. Also look down the chart for cities in america, are they all seriously dryer than UK as not one of them shows an EMC of higher than 18%. I'd like to see a real experiment of a log of moisture content determined by oven drying suspended in free air under cover outside. @Mike Hill mentions airflow and this is far more significant than one might think because diffusion alone isn’t enough to move moist air away from the log. My little experiments with single logs point to this also as they seem to do better than logs in my log shed. I should have weighed some sample logs and marked them before embedding them as I filled the store in May. Just consider how wet roads dry out in a day without rain even in January, so drying is still taking place mid winter albeit not much but if the wind is free... A m3 stack of beech logs at 21% mc wwb probably weighs about 280kg and has about 53kg of water, to get it to 19% means removing 6.25kg of water and the latent heat of evaporation that needs is 4kWh ( the heat in a1kg of 20%mc log), the trouble is that if the moisture in the logs is homogeneous the temperature would need to be high enough to get to all the log and the heat losses from that could exceed the heat needed to vaporise the water. One way would be a first in first out queue blowing warm air from the first out end with maybe4 days log deliveries in the queue in an insulated tunnel to polish off the few kg of moisture. We can have a separate discussion on how come there is a need for legislation and about selling wet wood when everyone knows dry wood burns well and green wood doesn't. It's a bit like gun law once garage forecourts stop selling wet wood then the people burning it are likely not buying it but getting it free and burning on an open fire.

On 6 Jan I brought a freshly felled piece of beech 1287 grams to the side of the stove at 48% mc and two days later it was 33%. At the same time I brought a piece of holly into the house and it was 16% from my log store. This is similar to what I have measured from my log shed since I built it a couple of years ago. Last Wednesday I washed my winch rope and strung it up in the shed, today, despite rain on and off all week, it feels dry but then I am in a dry part of the country.

Arthur Cundey made two posts here 9 months before I joined and looks like got no responses, a bit of a shame as Cundey peelers featured in many yards and sawmills. Back to the today’s post and those angle grinder attachments; I have not used a cutter on an angle grinder other than the arborcut chainsaw tooth thing but find a cheap £50 750 Watt electric planer with disposable blades does a safer job of removing bark off single poles where the curve means a 4" wide cut is adequate. It's a damn sight better than the sharpened spades we had to debark potential telegraph poles with.

Trouble is now I'm finding it all too easy to fall into being a couch potato and online warrior and this makes me wonder if I would have kept as active as I did if I had taken a desk job early on.

I agree, it is surprising considering the trade is a bit of a luxury service industry, but can think of many reasons for this not least of which is that people have a bit of money which may normally have been spent on travel etc. This comes back to the way we as a wealthy society fail to provide for the parts of society heavily affected by changes. Just as we didn't plan an orderly retreat from mining, steelmaking, shipbuilding etc. and let those parts of the country, once the core earners, become relatively poorer than the elite finance professions centred on London. Instead we have created a situation where labour is is made inflexible by H&SE requirements for expensive certification. No we will never have a great reset, it's not human nature, but I'd hope for a bit more compassion as well as resilience and of course looking at those activities that are causing problems to the environment.

It has to increase but the worst thing is that if the site does not have a neutral return back to the point the three phases separated all that current travels back by earth. This is because when you put a balanced load across a 3ph supply the sum of the currents is always zero, so no separate neutral required, all the current runs in the three phase wires. If one phase is missing something has to be provided to return the current when both of the available phases are the same instantaneous polarity. I never got that far which is why I chopped trees down.

It's kW but as long as the motor rotates with little slip and no load very little current will be drawn until you impose the load of your saw motor onto it. Not having 3ph available to play with I am not sure but the second phase is 120 degrees out of phase with the other so a quasi rotating field exists, in much the same way a single phase induction motor uses a capacitor to create an out of phase lead coil until the rotating squirrel cages induces it's own or a copper coil creates a lag in a shaded pole motor. See above. As for imbalanced load I'm not at all sure but 15kW implies 62A at a power factor of one so yes there could be a problem at low power factors You've lost me there, I can see using a transformer on one phase can create a 90 degree lag which would create a non symmetric rotating field with the other two but two transformers? and my maths doesn't do the sums of sines any more and it's too late for me to go back to A level maths again.

So you have 380-440V between then and 230-250V between each and earth? Theoretically you could stick a bigger 3ph motor wiring 2 of it's terminals with the incoming phases and each coil to earth and then once that is spinning draw 3ph of each terminal as the rotating squirrel cage will induce the third phase. Mind it is 50 years since I studied electrical engineering.

I agree with your last point but not the first. In normal white and grey cast iron the sites where oxygen can get in are occupied by cementite,(iron carbide) and graphite. This is why you cannot cut cast iron with oxy-acetylene or oxy-propane cutters. It is also why you can often find old iron castings still sound but pitted when steel has rusted away in flakes. Stainless steel develops a thin layer of chromium oxide which prevents oxygen penetrating further, put it in an acid environment which strips away the chromium oxide and it corrodes. I have posted a picture in the past of a flue pipe made of 316 pinpricked with holes where burning damp coated wood had allowed an acid condensate to form in the flue.

Yes they are cast iron but doesn't cast iron resist rusting better than steel? I had assumed it was the pads exposing fresh iron that meant surface rust happened quickly.

Hi Roger Long time no see. It looks like your website fell foul of brexit

caught two on the lampshade this evening and put them out

Try TXM plant, we hired their road railers but of course mostly the mats were already in position. I think I might know where there are some discarded level crossing rubber mats.

There's definitely a queen living at the back of my bookcase against the cold outside wall because I saw her fly there from the log basket.

I'm fairly sanguine about nuclear energy but this business of committing future generations to managing the waste is why I wouldn't support it because we have built our riches and wealth on fossil fuels and there is no saying future generations are going to enjoy the standards we have had for the last 50 years. I actually believe it could have been done much better but it wasn't and there is already a terrible legacy. I have a reasonable chance of dying within the next five years but I do have grandchildren to consider.

I'm late to the fray so will miss many points but yes leaf litter is valuable, it is how the mycorrhizal association the roots have to extract mineral is then left to benefit the surface humic layer. I think the reserves of soil organic carbon are huge, especially in peat bogs. Which of course are respiring carbon away as we get warmer drier summers. While I advocate intervening in the photosyntheses-rotting part of the carbon cycle and making some carbon recalcitrant I obviously would not want to see it impacting on soil organic carbon.

I think you're splitting hairs a bit deciding whether you count net carbon zero as you fell the tree or from the point you plant it, the issue is that the sustainable bit is that as much tree biomass is growing each year as is harvested (or falls down and rots back to water and CO2). In fact we know that in many places forests are being replaced by grazing land or other uses so their wood is not sustainable. The was a book written by a senior forester with the FAO maybe 40 years ago where he points out that man has been turning virgin forest to agriculture since the stone age and at the time he thought half IIRC the excess CO2 emitted into the atmosphere (and by implication the 45% of that that is in equilibrium with surface waters of the seas) before the industrial age came from forests that were felled in the tropics from Tudor times onward to grow things like sugar for us in the north. The inference is that the climate was being modified by man before he discovered fossil fuels but the fossil fuel era has only taken off in the last 100 years.

It was largely promoted for ARBRE a gasifying generation plant, when that failed to materialise...

I suppose that 2kW refers to a heating element? We experimented with Coanda effect for gas mixing in our kiln and made several devices well before Dyson came to the market. I came to the conclusion that they conserved momentum but not energy very well so not so efficient. Also I think they are bypass filters as only the higher pressure air powering the blade-less design gets filtered doesn't it. I would like to build a domestic wet scrubber and dehumidifier possibly with an electrostatic stage which would give just a tiny bit of ozone (to match outside air on a sunny day) and so dispatch bugs as well as catch very fine particles. I was taken in by Dyson's multi vortex separators and bag less vacuum cleaners until my colleague and firm's chief designer explained the energy cost, he should know and when we folded went to Rolls Royce and now, twenty years later, is a senior design technician in their gas turbine division. For my part I acquired quite a few Dyson cleaners when they got binned because the filters were blocked, it was a surprise to read that they should not be used with fine dust. I think they are only for clean homes. I have got a few Henry's too which were binned because the power cord fails inside the insulation where it flexes on the attachemnt to the recoil drum.. Replacing the bag is less of a chore than tipping out the dyson container into the bin and getting covered in dust. The HEPA bags are cheap and efficient. I might just get a pre cyclone for the workshop to save on bags filling as per @Paddy1000111's link

Yes that's what I use I was issued with an ash bucket precleaner for cleaning the flyash traps in industrial chip burners, it attached inline with the numatic and most of the fly ash settled into that so the vacuum cleaner filter didn't get clogged, it was all metal in case the ash was still hot, I used it once as it was such a faff to use,

How will you be establishing the weight? In the past it was easy with sawlogs, run a length tape along them and a Qgirth tape around the middles and either tag the end and write the volume in a book or paint the volume on the end.

I put that wrongly, it's particulates that increase during the evening. As it was raining steadily this morning I sampled the outside air, expecting some of the particulates to have washed out but I got figures of ~7μg/m^3 for PM2.5 and 10.5μg/m^3 for PM10, inside the figures were about 2μg/m^3 PM2.5 and 9μg/m^3 PM 10. Bearing in mind PM2.5 are a subset of PM 10 in this device it shows how the smaller particles are almost certainly smoke. There was a big spike of PM10 as I moved the device and then several spikes as I ashed out the stove, all predominatly PM10. So I think that my thought that moving around acauses larger ash particles to be lofted is likely. A long time ago someone, @kevinjohnsonmbe I believe, had a fine filter for indoor air to reduce a family member's allergies? Anyway it is something I am considering but I want to try and make my own. Yes Kevin I have little doubt air changes in supermarkets are too low and some of this will be due to costs of all the lost heat unless they have whole building air heat recovery. I haven't been to a supermarket for a year ( spend a bit more at the corner shop where there are seldom other customers) my wife gets the occasional delivery but as with tube stations, buses and railway carriages I would expect them to be hot spots of virus. I still don't know how efficiently a virus could be filtered out.