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Matt S

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About Matt S

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    nr. London, England

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  1. Well done getting it working, but easy on the sodium bicarb. Veg tanned leather is supposed to be mildly acidic (pH around 3-4 IIRC), and if you take it above its as-made pH it'll break down quite quickly. On the rare instance I use vinegaroon type products I just wash the thing out in plain water rather than adding bases. This brings the pH up a little, which is close enough to its "natural" pH that I think it makes little odds.
  2. Ron Edwards, an Australian bushman, horseman and general craftsman who grew up in his family's saddle shop, had this to say when making a nail bag: Heat, sunlight, salt and water (from the environment or the user) significantly affects leather. The effect on veg tannages is especially noticeable. Over time the oils, greases and waxes that are added at the tannery or on the manufacturer's workbench are lost and so the fibres of the leather shrink, get brittle and do not slide smoothly against one another. Some treatments (such as oil) are far quicker to leave than others (such as grease). This is where periodic cleaning and dressing of the leather comes in, which is sometimes called "feeding". Proper maintenance of leather gear has largely gone out of the average population's skillset, at least where I live. I've had to show grown adults how to apply a tin of Kiwi and a pair of brushes to their smart/formal shoes. Or even the concept that they can/should be polished every now and then -- let alone periodic cleaning, inspecting and greasing their belts. Like Ron Edwards I find it worthwhile to take into consideration the skillset/mindset and workload of the user when choosing materials. People likely to be outside in all weathers tend to get recommended chrome tanned goods rather than veg tanned.
  3. Short answer: yes sewing across a strap does weaken it. Real-world experience of low-strain, low-stakes items means that with a little care in the design and manufacture it's not weakened enough to make any difference in the real world. Look at the countless examples of dress belts, wallets, watch straps and cartridge belts that are sewn the "wrong" way and last for decades in daily use. In stitching across a wallet (e.g. for a spring tube money clip) I would be more worried about stitching too tight to the tube so it strains or deforms, or so loose that it might fall out, or about selecting the temper of the leather, or about a dozen other things before worrying if the leather might tear. Long-winded answer: Engineering in the more general sense is sometimes described as "the art of balancing the ideal with the possible". Making a wallet out of a 1" stack of top quality leather would make it robust but undesirably bulky, heavy and inflexible. The other extreme of folding and stapling a couple bits of garment leather would be frail and stretchy. Hitting the middle ground sweet spot between those two extremes, while also hitting other marks like "subjective aesthetics" and "cost control", is the unwritten goal of what we leatherworkers do. Just as hobbyist and artisanal woodworkers may eschew such modern things as particle board, biscuit joints and CNC cutting, so too do hobbyist and artisanal leatherworkers often eschew things like tubular rivets, edge paint, machine sewing and yes even stitching across a strap. There are circumstances where any of these materials and techniques may be inappropriate. One solution (which works well for the hobbyists, artisans or person otherwise wanting to keep things simple) is to reject them all. "Never sew across a strap" is a fairly foolproof and reliable way to eliminate the potential problem of that strap tearing off. "Don't sew across a strap if it's likely to tear within the projected lifetime and use-case of the item" is a far harder rule to follow because it depends upon a lot more bits of knowledge, which may not be available. Experience (direct or indirect, statistical or anecdotal) starts to fill in a few of those knowledge holes and may provide a different answer. Certain trades tend to err in one direction rather than another. Boatbuilders are very unlikely to use biscuit joints on a boat hull because they're likely to fail in a marine environment and somebody die. So too saddlers may choose to never stitch across a strap because if you do that on a girth/cinch it's under a lot of strain and if it fails somebody could die. Build a coffee table using biscuit joints and it's not only far less likely to fail in its expected use, but if it does the worst outcome is some spilled coffee and a stained carpet. A wallet maker is similarly free to be less strict with their selection of materials and techniques -- no wallet is expected to hold a 200lb man on a 1500lb horse in all weathers at 30MPH. The thing with engineering is, when you have unquantified or hugely variable materials and fastenings, it's difficult to calculate for. Leather is a hugely variable material so there's no specific numbers to plug into things like shear force calculations. We rely on common sense, experience and rules of thumb to develop ranges in which those numbers are likely to fall. The more datapoints we have the narrower those ranges can get but it's really all just an opinion and judgement call. That's why leatherwork is and art! ;-)
  4. I'd also throw my vote behind having a cutting die made. If your hand punches don't work, something's going wrong. Have you sharpened them? They're basically knives or wood chisels, but wrapped into a ring. They don't come sharp and need maintenance. If the plugs aren't ejecting try to see where they're hanging up -- maybe rough tooling marks or a sharp shoulder at the top of the bore where the plug changes direction to come out the ejection port. Smooth any roughness with a fine needle file, a rotary burr or some emery string or something. Remember that small punches are tricky to make cos they're so tight inside. I'd expect a 2mm punch to be used on a watch strap not a dog collar. The buckles I use for my 1/2" dog collars use a 4mm punch. As a more general note I think that beeswax isn't a great tool lube for leather -- it's far too hard and sticky. I prefer glycerine or saddle soap, or if the leather is very hard, thick or grabby plain old dubbin/grease. Dip it every now and then soo as it gets grabby again. Oh and on drilling leather yeah it's not a great practice but it can work. I like it for when I've painted myself into a corner and have to make a high-aspect hole (narrow hole in a thick stack of leather). I've found better success with brad-point ("lip-and-spur") drills than twist drills, since the former score the fibres around the circumference of the hole for a neater cut. Back each hole up with a piece of scrap wood to avoid blowout and move it along when it gets torn up. Spinning a punch, even a mediocre one, in a drill may be a better solution, so long as your drill runs slow enough and your punch runs true in the chuck. That's how they drill paper AIUI.
  5. Weird, cos the article linked in your signature (on a particular manufacturer's website, promoting the capabilities of their machines) appears to be written by "An Lee", rather than "Zach". If you're anything more than a poorly disguised shill for a Chinese manufacturer of laser cutters perhaps you could provide an an article you are proud of enough to put your own name on? Or show your own work? Otherwise, I declare "cobblers awls".
  6. Hi @ClassicCrafter, is that US-based thing non-negotiable?
  7. If you run some colour down that edge she'll be right. Sharpies work pretty well for raw edges.
  8. It's normal -- that bluey-grey is the "natural" (undyed) state of chrome tanned leather, just as a pinky-beige is the "natural" state of most vegetable tanned leathers. All it means is that the leather isn't dyed all the way through ("struck through"). This may be an economical measure (less time and dye) or may be done deliberately (as some dyes can affect the handle of the leather).
  9. That texture often results from the leather being run through a machine with a fabric substrate -- a belt or a pad usually. Is the grain side embossed/plated by any chance?
  10. Beautiful work! It's like a resin table, except I've actually got room for one in my house.
  11. In the 4 years since I made that initial suggestion I've stripped a few more machines down and run several million stitches. Some machines have enclosed/sealed oil baths around the pinion gears, complete with watchglasses, gaskets and fill plugs. Others are completely open to the elements, where anything liquid will dribble onto your knees if the drip tray isn't installed. Many run halfway between, with closed (but not sealed) boxes to mostly keep the schmoo in and the crud out. Still others have pumped oil systems, but we don't use those much in leatherwork. As others have said gearbox oil is designed for cars where the gears, undergoing significant pressure and wear that isn't seen in a sewing machine, are kept wet in a bath. It's relatively high viscosity oil but not, in my humble opinion, high enough to prevent it getting flung off unsealed pinion gears. When I suggested gear oil back in 2018 I was overthinking things. These days my machines with oil baths around the pinion gears get white sewing machine oil, same as the rest of the machine. Unsealed gears get lithium soap grease (and a complete strip and regrease if it looks manky). I like simple.
  12. Those glue pumps have tempted me for years but honestly I'm worried I'm just gonna be too lazy to clean it every day and going to find it solid one morning. Do they tend to clog/dry quickly? This. I used to use contact cements from the DIY/hardware store or builder's yard. Evo Stik, Everbuild or own brand mostly. All were usually too thick. How much too thick depended on how quickly that store turned over stock. Thinning made things much better -- better wetting out, better adhesion, better economy, reduced glue lines and faster tack. I found that most brands of glue and thinner were compatible. Since I swapped to industrial leather-specific contact adhesive (Anglo/Abbey 441) I found it comes the right thickness right out the tin (like emulsion house paint), it's cheaper than hardware store stuff and it works even better. Thinner is relegated to the jar where I store brushes and for when I don't go through what's in the glue pot quick enough. Thinking about it I don't even buy thinner these days. I looked up the primary ingredient on the manufacturer's safety sheet and buy it directly from a lab supply house for significantly less £.
  13. Get Leprevo to make an embossing plate. For their minimum order (~£50+VAT IIRC) you can get a variety of different sizes and designs made up. They are photoetched from zinc in the UK and very easy to cut apart and mount however you want. I do them on billets I can quick swap on one of my heated presses, but others epoxy them on handles you can thump with a mallet. Other than value and speed, thanks to the method of manufacture these have a good draft angle which makes easier pressing and give better colour when heated.
  14. It's an interesting idea. What would be the workflow? I wonder how many paper templates can you print out versus the cost of a projector? For me the repeatability and speed of a solid card, perspex or board template are very useful -- especially where for thin leather you can just run a knife around it, or for thicker leather a scratch awl, and the knife follows the awl mark. I'd also be concerned about being able to move the leather around as I cut it.
  15. @Stewart I am very sorry to hear of your loss. I'm sure that your support, strength and love were a huge comfort to her over the time when your lives ran together and especially when your paths started to diverge. As Gus McCrae says life is short for us all, shorter for some than others. Hopefully you can rejoice that you had the time with Lois that you did. Nothing I can say or do will make things easier for you or your family but I find during stressful or difficult times I find it can help to talk with people, especially people outside of your regular or immediate circle. Being honest about your thoughts (whether you think them "fair" or "mean") in a way that you might not be able to do with people who were fortunate enough to have known your wife. It can help to crystalise them for you and find a positive direction. If you feel the need to blow off steam to a semi-anonymous person please feel free to PM me. That offer applies to anyone on this forum going through difficult times, not just you.
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