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Matt S

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  1. Yes I think you may be right -- we have "full fat" single phase 240v (the European harmonised standard is 230v, but it's really 240v in the UK and 220v on the Continent and usually around 244-247 depending on loading conditions in my workshop) delivered as a minimum. Usually about 100A from a 25-35SQMM service cable (either direct buried or ducted), or 60A for small houses and flats. In reality it's a single phase from a 3ph generation and distribution infrastructure. It's not unusual to have 100A 240v 3ph service to normal houses and small commercial buildings, and I think will become quite common with the increases in electric vehicle charging, a general move away from gas and oil heating, and microgeneration that's expected. It's already common in mainland Europe. In fact we've got it at this house but only a single phase to the service cutout, as it would have cost a lot more in installation and internal wiring costs when we made alterations. It's significantly cheaper for me to run a converter when I occasionally need 3ph than it would be to wire for it. AFAIK we only get split-phase stuff as temporary supplies on building sites (110v, arranged as 55-0-55 centre tapped to ground). We're moving beyond my ken here, as for obvious reasons I only really know how to fanangle our setup. Have you considered a rotary in a "hush box" like for compressors, or maybe installed remotely in an outhouse?
  2. Very neat work as usual Danne! What's the leather?
  3. As others have said, it's a disquieting story with a lot of empty holes where information ought to be. I'm not one for jumping to conclusions 5 minutes after the fact but if no further details have been released 2 months later something doesn't smell right. Maybe someone saw five when there was only 2 and 2 in front of them and twitched if you see what I mean. What's the procedure for investigating a death like this? In the UK all deaths are investigated by a coroner, who then will pass any findings of potential wrongful death to a relevant law enforcement body (usually not the one involved). There's also an automatic self-referral of the police force involved to the independent police watchdog in the event of anyone getting perforated, no matter how justified. It sounds like Mr Kotanko is a loss to the local and international communities. I don't know what Ontario Police SOPs are but in the UK it's been standard to arrange one more ambulances ahead of time if a raid is planned where firearms are known to be present or officers with firearms are sent in. It's not the police's job to be executioner, and it could easily be one of them that gets perforated rather than the suspect. I'm not sure I'd read too much into one being present from the off. I don't really want to get into politics here but the apparent ramp-up of anti-gun unilateralism in Canada the past few years has made me rather uncomfortable. Moving vast swathes of firearms from "non-restricted" (not registered or recorded, just possession of a general licence required AIUI) to the "verboten" list in one fell swoop is idiotic in the extreme. Not only do I disagree with the general thrust and "logic" <coughcough> behind the ban (it's the nut behind the butt which is the biggest potential danger to society IMO, not the hardware in front of it) but there's obviously going to be huge amounts of accidental or deliberate non-compliance, along with overcompliance from people who aren't quite sure what's suddenly turned from a tool or a toy into a massive legal liability. If I were minded to such things I'd cry "conspiracy" but I am a strong adherent to Hanlon's razor as a general rule so, like most bad law, I chalk it up to ignorance and unintended consequence. Mostly.
  4. It might be that static converters are setup to run a little differently with our electrical grid over here, but as I understand it static converters make an ersatz third phase from the supplied one through a capacitor as you say. That makes this phase lag by roughly 90 degrees, which is "close enough" to the ideal 120 degrees to work okay under most circumstances with a slight loss of voltage and increased noise and vibration due to imbalance. This is the minimum it takes to run a 3ph motor on a 1ph supply and is sometimes called a Steinmetz circuit. It's possible to make a second ersatz phase by connecting a suitable inductor between the first and third, which will lag behind the third (or ahead of the first), which will help the motor to balance a little better and provide a little more power. As more or bigger motors are run simultaneously the closer to 120 each phase will be, and so the better balanced everything is. I ran my 4-motor Fortuna splitter off a static for a few years and you could hear the motors become more balanced as they kicked in in sequence. This is essentially the basis behind a rotary converter -- a big "dummy" motor with no load which is used as a triangular array of inductors with reactances that vary at the right speed all at 120 degrees from each other. Sometimes static converters have a bank of capacitors which are switched in and out of circuit manually or automatically in order to regulate the voltage drop from L1 to L3 across varying loads, however there is always a "run" capacitor in-circuit when running. They will often though have a larger "start" capacitor to get the motor turning, which is only in-circuit for a few seconds before being switched out.
  5. How about adding a welt the same thickness as the D-ring bar underneath that top-piece? Then the top surface of the top piece would be flat and you could sew as close to the D as you like. On longer pieces you could skive the welt down to a feather edge a short distance from the D so it tapers up to the D ring from zero (taper length an dangle depending on how fast your machine can climb). Or just forget the backtacking and go round in a single course, overlapping your first and last 2-3 stitches. This is something I prefer rather than separate start/end points because it's faster, looks neater and is a bit more reliable tensioning 2x sets of stitches into one set of holes than 3x sets of stitches. If you can't get close enough to the D on one of your short sides due to the bulk of your foot set, try turning the piece the "wrong" way and going in reverse for that side.
  6. I'm not an expert on 3-phase, but from what I can figure out VFDs are actually only any good when directly driving a motor. Nothing -- no contactors, no brainbox, probably not even an overload breaker -- should be between the VFD output and the motor coils. The VFD also tends to need to be programmed for the motor size and load, and of course for any inputs (e.g. controls or sensors) that you might want to use to influence the action of the motor. They're not clever/robust enough to make a more general-purpose 3ph supply from 1ph. Static or rotary converters are more of a generic "1ph in, 3ph out" type converter, but each has its own strengths and weaknesses. Or, I suppose, a motor-generator unit would work, or a fuel 3ph generator. Depending on what you got at what price, and how many bells and whistles you actually want to be functional, you might just be better off flogging the 3ph electronics and buying a couple of good but basic 1ph servo motors.
  7. I saw this a few months ago and am really curious to tear one down. If it works it'll be a massive game changer, certainly for the hobby leatherworker. I have a "real" band knife splitter, a Fortuna UA. It's a pretty standard 12" model but a little old fashioned. Weighs 800lb including the cast iron frame and stand, 4x induction motors totalling 1.5KW, and the precisely machined steel adjustment mechanisms. Modern equivalents weigh about half that. Before I got my machine I was shopping Camogas with the UK dealer. The chap I spoke with said that they are still so massive (in volume and weight) because that's what's needed in order to tension the knife without distorting the frame. Just no getting around it, basic physics. Having now been elbow-deep in my Fortuna many times I completely understand. That's the first red flag to me about this desktop version: it doesn't seem sturdy enough to withstand the tension needed on a standard band knife splitter blade. I suspect that it's not a full width blade, to avoid stress on the frame. If the blade is narrow it'll have a relatively short life and be more prone to variation in split (the leather will be more likely to veer into or away from the blade).There may also, in the real world, be an excessive distortion of the frame causing things like blade crashes or splits that vary across the width of the leather. The blade sharpening is another issue for me. Band knife splitters, like most edge tools that work on soft materials, absolutely rely on a perfectly honed blade. Leather is an abrasive material and so the blade needs sharpening frequently. On "real" band knife splitters there are a pair of emery wheels which sharpen both edges of the blade at once, to prevent burrs. This may be adjusted for either constant or just frequent grinding. The desktop model appears to use sticky-back sandpaper to sharpen the blade, which I would think would cause a lot of problems with uneven bevels, clogged sandpaper, and being inconvenient enough to not happen as often as needed. The size of the knife wheels can't be very big either, which again hints at maybe a skinny blade or one that's likely to crack prematurely. Just like with a bell-knife skiver scrap sticking to the feed wheel is a common problem when operating a band-knife splitter. The solution is largely the same: a vacuum extractor which pulls the scrap away as soon as it's free. There doesn't appear to be one on the desktop model. This may also be a health hazard as the same system captures dust (from the leather and from the knife grinder) and keeps it out of the operator's lungs. Band knife splitters have a bewildering range of adjustments, mostly for spacing, parallel and tension/tightness. All have to be very nearly dead-nuts-on to work reliably and "want" to shift with vibration, or even to adjust mid-split due to the forces exerted. Frankly I have seen few Chinese-made mechanical devices where the adjustments were accurate, smooth or held tension well. I know that not all Chinese products have screws made of cheese but colour me sceptical by experience. As a result reliability, repeatability and accuracy are likely to be suboptimal. There also seems to not be enough physical space in the machine for half of the necessary adjustments, which would leave them factory-set and prone to wear. Speed also seems to be something that the desktop splitter doesn't do well. That's not the end of the world because it's not exactly a production machine but I bet splitting the components for a half-dozen billfolds would get very boring very fast. It is my repeated experience that electrical safety of direct-from-China machines (rather than made in China to Western design/spec machines) leaves a lot to be desired. This a mains powered metal cased machine. I make it a policy to check the wiring of any mains powered machines that don't come through a proper UK dealer. I have never wasted my time by doing so, and never had to not correct a design or manufacturing fault or shortcut. Similarly mechanical safety may not be up to snuff, certainly for use in a workplace, but I'm not well qualified to discuss that. Finally, it looks like feed roll tension is adjusted with the pair of silver hooks under the front. They look like they're straight off a bell-knife skiving machine. I doubt they're up to taking much tension, and certainly don't have much "granularity" of adjustment (5 steps IIRC). Maybe the fine adjustment is what that wheel's for. It certainly doesn't seem to be up to the sorts of tension I have experienced on a "real" band-knife splitter, though admittedly I have only run a grand total of two. For reference I weigh about 160lb and have to put at least a quarter of that on the pedal to counteract the tension on my Fortuna. Well that depends on exactly how "tolerant" an individual may be on thickness. 0.1-0.2mm thickness variation across a hide is pretty standard these days and for most projects there's a fair bit more leeway available. I'd say that location on the hide, grain orientation and choice of hide for appropriate hand/texture is probably important than getting exactly the correct thickness to the nearest 0.1mm. I understand that having leather split can be difficult with minimum orders but once we're talking about plonking down $5K you could probably afford to get every hide you're likely to use split to every thickness you're likely to want. 100% with you regarding the bell knife skiving machine. I just hate adjusting mine (never been much good at it) so once it's set for a job there it tends to stay until I really need to adjust it for the next one I can't do without it!
  8. I'm going to take that as a yes. You make some cool looking stuff. You have an eye for design and you're clearly pleased with your work, but I really don't understand why you like to imply on the internet that you're actually stitching the leather through with your machine. The amount of effort you use to get that contraption to do something it's really not suited for is impressive. If you presented the steps and time it takes you to use one of these machines to put 207 size thread through holes you've already punched through the leather on an open forum, with an honest discussion about its severe limitations that several people have tried to discuss with you, I'd be more impressed. This forum has some of the most honest and generous tradespeople I've ever encountered. I don't think it's fair of you to advocate to beginners to spend their time and money on something that, at best, will need a considerable amount of skill to sew leather to a mediocre standard at roughly the overall speed of hand stitching.
  9. Is that with or without pre-punching the holes?
  10. One of the great things about making stuff out of leather is that there are many ways to skin a particular cat. Your design is very clever for being so efficient. I think that I would prefer the design in the OP as it appears to have more positive retention and the increased rigidity is less likely to rotate up on the belt during a hasty reload. To each his own.
  11. Well yes and no. Piss was used as a weak base in the pre-industrial world, and amongst other things used in the liming of hides (soaking in a basic solution to aid in removal of hair and fat before tanning). Tour any tannery and you'll find some rather pungent scents in the "not yet leather" stage that you wouldn't want in your finished product. I've dealt with bodily fluids from many animals and wouldn't countenance anything that came out of the hind end of a carnivore in my workshop. I certainly wouldn't want to inflict that on my customers. If it were me I'd cut off any particularly bad sections and bin them, then wash the lot in plain water with some vinegar thrown in, and allow to dry flat. Especially somewhere with a breeze.
  12. That's a neat design! As @Hags says, once they got the design just right it's an ideal candidate for a clicker die. I reckon it's regular old tooling russet. Maybe some skirting scrap if they had a source from a Western style saddle maker. Shoulder would be my preference, but any not-too-stretchy part would do fine. How much leather do you guesstimate is in the thing? Maybe a quarter to half a SQFT? Even if it came from "virgin" hide not scrap/offcut you're not looking at an awful lot of $ of raw material...
  13. Well you didn't exactly make it clear in your OP that you were looking for the cheapest supplier, just that you were struggling to get any! I was "there" in 2020, most of my business is dog collars. I was scouring every supplier I could find in the country for suitable buckles, cleaning most of them out. Most of my leather suppliers either closed their doors for a while or couldn't restock. I ate some of the increased costs, raised prices a little, and simply turned away work when I couldn't get materials at the right price. After that I started reading about business resilience planning. $2 hook on a $14 item. That's a tight rope to walk, especially if that includes postage. Part of the problem when selling a narrow-margin product is that any price increases eat into your profit, and something has to give. Buying/stocking large quantities of material helps to get a lower per-unit cost and insulates you some against price and supply issues but you're still relying on a chain with an awful lot of links, many of them recent world events have proved to be be far weaker than previously believed. They're showing out of stock RN, but it may be worth reaching out to Weaver (some of their lines are getting restocked very soon). Their solid brass 3/4" square eye swivel hooks are <$2 in small quantities, and looking at my wholesale catalogue significantly less in large quantities. I would again suggest that you avoid relying on retail-type wholesalers (middle-men resellers, probably a lot of their product coming from China) and research US-based trade suppliers and manufacturers. As I said before UK "hard" manufacturing is a fraction that of the US and I've got several to choose from. There's got to be something for you Stateside. (Incidentally VAT would be discounted for a sale outside of the UK, it's a domestic-only tax.)
  14. @TomG I've bought hardware from China when I can't get what I want from closer to home, but can you seriously not find it in the US? The UK has a fraction of the manufacturing capability of your country and I have two foundries I order from regularly. Often with next-day shipping. They're 2-3x the cost of the ones from Chairman Xi's Workers' Paradise but it's well worth it for the quality, the speed of delivery, and keeping the money and skilled jobs onshore. These are the two I use, both long-established firms in Walsall, the traditional home of English saddlery and associated leather trades: https://www.abbeyengland.com/ (you'll need to sign up for an account to see prices) https://www.fmartinandson.co.uk/
  15. I've bought some stuff on there. Rivets, snaps, and a few small pieces of machinery. Not my preferred choice of marketplace or country of origin, but there are few options for what I was after. Everything has worked out that I've bought from there, but wouldn't buy leather from there. There are far better options for not much more money, and not all leather is made equally. My time, even when doing hobby rather than job leatherwork, is worth more than the difference.
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