agg221

Spruce is what a most basic workbenches are made from, or you would end up with if you used lengths of joist to make one, as my Grandad did some 60yrs ago. That bench is sat in Mum's garage - the top is far from pristine but it is still perfectly serviceable. It was well dosed with something at some point, probably creosote, but now more like oil from the various engines etc that have been dismantled on it. It's fine - no woodworm, no rot, will do at least another 60yrs. Spruce and poplar are both pretty resilient - they take knocks and dent a bit but lumps don't fall off. Oak is far more vulnerable in this respect. Poplar and spruce are about equivalent in hardness on the Janka scale (approx. 400-500). Sycamore is a bit harder (770), ash and oak are around 1300. Note, I can't find a perfect match on species as I can only find American values, but they're not far wrong. In my view, hardness is important if you want a nice stable workbench to lay out fine woodwork, but for bashing lumps of engine around it will get dented anyway (no practical timber is as hard as a lump of cast iron!). I prefer poplar over spruce as it is more absorbent. It will take up a spirit-based insectide, followed by something oily to seal it. It will then be pretty resilient for a good few decades. I would avoid oak as the tannic acid is corrosive to steel parts. Alec

Of your list, poplar or sycamore. Poplar is a lot better than people give it credit for. It also soaks up oil really well which then means the woodworm don't like it. It is used for the beds of artics. Alec

Had an elm stump wash down the river, complete with major roots. I reckon it's about 18" across, stump length about 2'6". The base should be pretty gnarly grained. It's dry enough that the bark has gone, but seems completely sound. Any good to anyone before I log it up for firewood? Alec

Shouldn't need to spray them - just leave them and any which grow back suggest that he knocks the re-growth off around next June - that should finish them off. Drilling holes down the centre helps them rot fairly quickly - I've found around 5yrs although the oak will last longer. Interesting point on nitrogen - not really considered this. A heap of grass cuttings over the top would be one way to boost nitrogen levels. Alec

I absolutely concur with this, and it holds true in any field. It reminds me a bit of times tables. In my day you learned them by reciting 'once two is two, two twos are four' etc. They are now learned apparently as just 'two, four, six' etc. The former method meant that if someone asks 'what are six sevens?' it is so embedded that I can still quote 'six sevens are forty two' without even thinking about it. My daughter who is learning times tables at the moment can't do this because the method she has been taught doesn't get her there so quickly. However, neither method actually gives you mathematical understanding, so you can't translate the above into 6x70 unless you actually understand what you are doing. Education can lay solid grounding to allow you to do tasks better. The application of that knowledge can be communicated (more efficient, high success probability), or figured out (less efficient, lower success probability but often more easily remembered once done and sometimes the only way if nobody knows), but the knowledge is worthless until one or the other of these routes has been followed. Alec

Some detail pics would be good please! Cheers Alec

I agree with the theory... I reckon annular ring shank let you get away with a bit less where necessary - e.g. I am fitting 3/4"-1/4" feather edge cladding to 1" battens, so can only get a maximum of 2" in there. I'm using 50mm annular ring shank and I'm not worried about pull out. Alec

Elder daughter (5) is sat with me, has just seen this and now she wants one! Anyone taking down any larch round my way.....? Alec

In all honesty, I wouldn't bother with a nail gun. A nail gun is great if you are going to do an enormous amount, day in, day out, but for the odd shed/dog kennel the time saving from using a nail gun over a hammer is trivial - most of your time will be spent measuring/marking and cutting, rather than fixing. Length - I like at least as much nail length holding the thing in as its own thickness, ie for 25mm shiplap, use at least a 50mm nail, up to 60mm if the structure is deep enough to hold it, 19mm shiplap use a 40 or 50mm nail etc. For more structural stuff, holding 50mm to 50mm a 100mm nail is best. If you don't have much luck with timber things, I would go to the trouble of drilling pilot holes and use annular ring shank nails - use the thicker ones as they are less likely to bend on you. A cheap cordless drill will make pilot holes all day long on a single charge. If you use 3.35mm nails and a 2.5mm or 3mm pilot drill it will work fine, bend less, give you heads to pull out on the ones that do inevitably bend, not split the timber even when you're a bit close to an end and prove far less annoying overall. Obviously scale this up for the structural ones. I buy nails from Tradefix direct - fairly cheap and I buy the stainless ones as then I can use them with oak/sweet chestnut/cedar without it staining black, or having to keep two bags. Alec

It should, although there is a risk that it pulls through if the board is a long way from quartersawn and trying to cup heavily. Coach bolts would be more certain. You could try a pair of your screws, fairly close together near the centre of the board, say 2" apart so the relative shrinkage of the board in between them is minimised. Don't forget that the board will also shrink in thickness, so you will want to be able to nip them up a bit, probably next summer. It's easy to do this with bolts, rather more tricky with screws as you will have to clean all the heads out by then to get the driver back in. Oh and last night, I should have said 'smiling' rather than 'frowning' ie the bit from nearest the centre of the tree upwards. Alec

I don't bother - oak is acidic anyway and if you have rinsed reasonably well it will be fine, and be neutralised when it hits the concrete. If you particularly want to, probably sodium bicarbonate is the cheapest and easiest to get hold of, from the supermarket. Alec

If you can edge out all the sapwood, I would leave it untreated. If you need to keep sapwood in I would definitely treat it heavily - I never find oak sapwood to be at all durable (often just let it rot off before I mill given the choice!) When you bolt down, fit the boards 'frowning' rather than 'smiling' as it will reduce cupping and any that you do get will help water shed between the gaps, rather than pond in the middles. Alec

It would worry me a lot! Run it on 15:1 and you will kill it, either because it's running lean (yes, really, too little fuel in the fuel:air mix if you take it all out and put oil there instead), or because it will blow the plug out (fill the top end with oil and you decrease the space for compression, so the compression ratio goes up). If by some chance it doesn't, it will kill you instead with the smoke! I would say however that if you don't use it that often it's worth swapping over to Aspen once it's rebuilt again. I would also suggest that this sort of saw just isn't his thing, and ask someone else to take a look. Alec

It should get rid of them completely. Alec

Oxalic acid can be had cheaply from a decent chandlers (noting your location - Milford Haven?) or a proper chemists, not just a pharmacy - they will have a catalogue, probably Sigma Aldrich, and will be able to get it in although it won't be cheap that way. Or there's always the dreaded Ebay. About a fiver for a kilo delivered - dissolve it up in warm water, brush on with a stiff brush and leave, then rinse. Alec

Is he using genuine parts or pattern? There have been issues with rings on the chinese pattern parts (I haven't had any, but I have heard of them failing). How many tankfuls between the first failure and the most recent? If it's not many, it suggests you may have an underlying problem that hasn't been diagnosed. Has it been pressure/vac tested? Alec

Definitely iron staining. Removing it - oxalic acid should take it out. Do wear rubber gloves as it's toxic. Alec

Ah - that which was formerly known as Prunus pissardi and is now known as Prunus cerasifera 'Pissardii' Alec

You do know that's one of Rob D's listings? Might be worth asking him what it is. Alec

I started off milling with an 064, then an 066 (ie 660) before I went to larger saws. A 36" bar is as much as I would want to fit (you can go to 42") which gives 28" capacity with the dogs on, 30" with them off. Doing this, it's slow. It works very well on a 25" bar milling at 18" capacity. You will need proper ripping chain, and I would seriously advise the Granberg precision grinder as keeping the teeth equal in length and angle (as well as sharp) is critical for good milling. Alec

I sometimes have some well air dried material surplus to requirements. Any particular species, dimensions, quantities of interest etc. Alec

What is the floor like? If it's fairly smooth concrete could you go to crates/stillages on pallets, load up outside and then pull them around on a pallet truck (hand or battery depending on quantity and length of run)? Alec

Elm is a really interesting one. English elm definitely isn't native to Britain - current thinking is that it is native to somewhere in Turkey. However DNA analysis (2004) identified that it is a single strain of Ulmus minor, rather than a distinct species. U.minor is more contentious - because it usually propagates from suckers it is not very fertile, but it can and does set fertile seed in the UK, about every 20-30yrs which is quite frequently enough for sustained propagation. It was also largely wiped out in the 16th century, probably by a previous strain of elm disease, so the current genetics are very narrow compared with what may previously have been. As such, there is nothing concrete as to whether U.minor is native or was brought here by man over the land bridge. The same is probably true of other species - did the acorns gradually fall further and further and north as the ice receded, or did a man drop a few out of his backpack....? Alec

I would second Rob's comment. I suggest starting with an Alaskan Mark III mill, probably 36" as this is about the length you would be OK with if you did have the double saw set-up, and in the meantime you can shorten it up to fit the 441. You would also need a suitable length bar - a 25" would give you 18" capacity, meaning you could mill a 2' log by rolling it. You will then need a ripping chain - personally I like Granberg chain as I find it cuts a bit faster and leaves a smoother finish, but Oregon is cheaper. You also need to consider how you will sharpen the chain - it needs to be both sharp and even in angle and length for good milling, to a level which is extremely difficult to achieve by hand. You could use a precision filing jig, or a precision grinder. Note, you would need a grinder for the Granberg chain. In the meantime, have a look at the videos Rob has put on youtube - you can find them linked from Chainsawbars ? chainsaw chains, chainsaw bars and chainsaw accessories Cheers Alec

My day job is in commercial engineering R&D, and I have been named on around a dozen patents over the years, so I'll try and set out the options. First thing is that to get a patent granted you need to prove an innovative step and that the invention is not obvious 'to one skilled in the art'. A trivial example of the latter would be if that if the longest log anyone has ever set a processor up to cut is 12" you could not get a patent simply by moving the guide out to 14" as it's obvious, but obviousness can get a lot more subtle and tricky than this. The purpose of a patent is to encourage commercial exploitation. It gives you a protected position for 20yrs to gain market share, in exchange for putting the knowledge in the public domain for general exploitation once the patent runs out. There are a couple of points in your original post which would warrant some thought - the first is that it appears that there is already a patent on a method for achieving the result; the second is that you are not looking for commercial exploitation. With regard to the first - have you reviewed the existing patent? Does it use the approach you have, is it completely different or is it somewhere in between (e.g. different, but not fundamentally)? If it's the same approach, this would form prior art and you would need a licence to access it if the patent is current (has not expired or been allowed to lapse). Your idea could be an extension of the existing patent, in which case you could get a daughter patent, but would still need access to the existing patent to use it. Fundamentally different approach, no problem; somewhere in between you would need to discuss with patent lawyers whether claims could be drafted in such a way as to not be compromised by it. You say you don't want to commercialise it, but you 'don't want your ideas stolen'. Why not? This isn't a flippant comment - you need to work out why. If it's because you feel moral ownership of the concept, you could become the acknowledged inventor of the concept by publication - write an article about it for a relevant magazine and this will form prior art. Alternatively you could file the first stage of the patent, which is pretty cheap, but let it lapse. Again, this will stop anyone else from patenting it themselves, although both approaches will leave people free to use the idea (you could look on this as altruistic). Otherwise, unless you want someone to exploit it commercially and pay you for access, you are effectively saying that you have had a good idea but you don't want anyone else to be able to have access to it in any form. This is regarded as counter to advancing the state of the art, hence patents are designed to prevent this situation arising. If you do want to take it forward, there are other ways. If you just want to get someone to build one for you, you might find a non-disclosure agreement (NDA) is more what you are looking for. This formalises confidentiality when you are discussing it with an engineering firm. If you need an NDA template at some point, drop me a PM as I can send you a standard one. Beyond this, you could look at selling access to the concept, either outright or on a royalty basis. You do not need a patent to do this. Formalised intellectual property (IP) in the form of a design right can be easier to obtain and is usually sufficient. If you initiate discussions under NDA, a company can't make use of the concept until you have reached an agreement. However, when thinking about this, consider that a company will only adopt a new concept if it can increase their revenue. If it allows them to take greater market share in a closed market, or extend the overall scope of the market, they may be interested, but usually only so long as the payment to you is a percentage of the additional profit they are gaining by doing so - otherwise they may as well not bother. Hope this helps. Alec edit: I would echo the comment about not disclosing the concept on here.