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Matt S

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Everything posted by Matt S

  1. If you run some colour down that edge she'll be right. Sharpies work pretty well for raw edges.
  2. 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).
  3. 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?
  4. Beautiful work! It's like a resin table, except I've actually got room for one in my house.
  5. 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.
  6. 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 £.
  7. 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.
  8. 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.
  9. @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.
  10. Supposedly the preference for left-vs-right sides is because cows' rumens are asymmetrical and expand more on one side after a good feed than the other. Grain in leather is less like grain in wood and more like varying levels and directions of stretchiness. Think of the way the beast's hide moves throughout its life. The belly expands and contracts with each meal, plus has to stretch to accommodate every shape the creature contorts itself by flexing its back. The ribs expand and contract with each breath, but only really in "diameter" (at right angles to the spine) and not length. The shoulders/forequarters move a little in all directions as the big shoulder muscles move the animal around, and the hindquarters do the same but a little less. The neck is in constant movement in every direction and the spine only does a little flexing. This basically follows how different areas of a tanned hide stretch. Cutting across a double shoulder (perpendicular to the spine) is definitely stretchier than along or parallel to the spine, all other things being equal. Whether it's "too stretchy" depends on the hide, the exact application (lady's fashion belt or framing carpenter's toolbelt?) and the individual craftsman's standards/judgment. I don't really like to do it unless the leather is particularly non-stretchy or it will be lined and sewn, both of which reduce stretch.
  11. @fredk I wonder if this is because the flesh side has more stretch to it, the fibres being coarser/looser than those of the grain layer? While it's something that I'd often "known" I had never considered quantifying the difference or what practical effects it causes. Thanks for providing an example where this slightly abstract material property makes a real-world difference!
  12. It's edge paint. Probably several thin coats over a sanded/profiled edge.
  13. You may be able to buy spares for these machines from one of the several sellers. Or if you strip it down and measure the piece (which I suspect may be a simple nylon tube) you may be able to buy a short length of standardish tubing to replace it. Failing that, as others have suggested, it's a simple job for someone with a lathe to turn from a piece of nylon or acetal rod. Even a wood lathe may be able to be used.
  14. Edge Kote is a product from Fiebing which is a combined colour and sealer for edges. I guess you can also use it to seal unfinished backs. I think it's a rather archaeic formulation of edge paint (in a bad way). I've never been happy with the results of Edge Kote, and I don't think it's up to the standard of modern edge paints from the likes of Norsol, Giardini or Fenice for instance. Modern edge paints can be very durable, bind well with the leather and previous layers of paint, are easy to apply, have a high "fill", are available in a variety of colours and finish effects and can be quick to dry. I associate none of these attributes with Edge Kote. I find that Edge Kote has all the "bad" characteristics which are often attributed to all edge paints, many of which don't apply to modern edge paints when properly applied. If this is what "accessible" edge paints were like "back in the day" no wonder so many craftspeople took against them.
  15. There are many reasons to use RFID blocking linings. One of the most common in my neck of the woods is avoiding "card clash" where you have multiple NFC-enabled cards in one wallet. Put your most commonly used ne (debit card for instance) in an unshielded outer pocket and your multiple others inside the protective cocoon of a Faraday cage and things work much smoother.
  16. My understanding of 45Ks fitted with reverse feed is that that secondary screw to the left of the stitch length adjuster (circled in red in @Constabulary's post) regulates the length of stitch in reverse. That is to say although it's a limiter it limits how far up the slot the stitch length adjuster can go when you make it sew backwards. The screw should be adjusted to match the length of forward stitch every time you change stitch length. Bit clunky, though I guess simple for the factory to implement and fine for production work where it's a case of "set it and leave it set". About par for the course with Singer's mid-century industrial machines!
  17. Oiled thread felts certainly help with friction and sticky glue. What oil do you use? I like silicone, but it's a swine to clean up if/when I spill it on the floor. This is the kit I was thinking of, and while I think that College Sewing is an excellent company I'm sure similar setups are available elsewhere. The nozzle looks pretty compact and I like that it comes not only with the valve but a regulator too. https://www.college-sewing.co.uk/ka-cns-needle-cooler-single-needle.html Alternatively I wonder if one of those ball-joint coolant nozzles would work? Should be long enough to screw it directly onto a solenoid valve or pressure regulator mounted directly to the back of the head.
  18. Brilliant bit of work Brian! I mostly use spring-guide feet rather than drop-down guides but think that the same idea could be applied. Then all I need is a limit switch and servo to turn the piece when I reach the corner... BTW you mention overheating needles. I generally use quite waxy/oily leathers so can get away with running my machines 2000+SPM. I think the heat dissipates by evaporating/burning off some of the excess oil but I expect that's not great for my lungs. Have you much experience with the needle cooler units? There's some neat little kits available that only switch on the air when the go pedal is down, to avoid wasting air. I'm tempted to try knocking one up with an aquarium air pump and bit of copper tube.
  19. As others have said, having more than a fathom of thread "in hand" at any one time leads to increased issues with tangling, unravelling, having to rewax the thread periodically, fraying and discolouration. I've done it, it's doable, but not my preferred way of working. Doubled-up stitches at changeover isn't hugely noticeable IMHO, are "honest" artefacts of how the item was manufactured, and it's often possible to hide them. On shorter belts it's also possible to start at the point of the belt with /two/ fathoms of thread. Pierce the centre hole and pull both threads through so they're crossing over equally, then start sewing down one side of the belt with the ends of opposite threads. Once you've reached the end start again at the point with the second pair of ends and sew towards the buckle. Of course this requires being able to sew equally neatly both towards and away from you. I've been hearing this a long time. Ron Edwards touches on how the idea probably became common, with saddlers directly comparing seams machined with skinny, slippery, stretchy synthetic thread (for light articles, rugs etc.) against chunky linen saddle- or back-stitched seams (for heavy and working articles) in the second half of the 20th century. I suspect also there's some mixup between lock-stitched seams and chain-stitched (which definitely do just "zip up" when you pull the right thread). Without meaning to sound rude or confrontational, how much experience do you have with threads broken on stitched leather articles? I ask as I used to believe the same thing. Now, with the experience of examining hundreds of such broken threads (through accident, wear or deliberate cutting) I can tell you it doesn't work like that. It is my experience (through direct study and asking the experience of professional leather tradespeople) that a "correctly" saddle stitched seam sewn in a decent thread with a grabby/hardening coad (not bloody beeswax or candle wax) /might/ be stronger than a lock-stitched seam... but I see precious little of that being done these days! For almost all practical purposes, when compared apples-for-apples, lock-stitch machine sewing is at least just as strong and durable as imperfectly sewn saddle stitching. I've handled plenty of items where one or more threads has been cut by wear or accident. Some (like the shaft tugs which hang above my desk) have the surface portions of both threads entirely worn away, yet are still solid. Similarly I've had to pick out plenty of machine-sewn work, that simply had to be cut and pulled out one or two stitches at a time -- same as saddle stitched. Others, saddle stitched even 100+years ago in linen thread, will disappear as soon as one of the stitches parts ways. The real difference in "staying power" in these cases is from tight holes (just big enough to admit the threads before they close back up, which is best achieved with a sharp awl immediately before each stitch, or failing that the smallest leather-point machine needle that will work), tight stitches, thread (preferably linen) saturated with proper drying stickywax (hardball or polymerising liquid), and a design that minimises reliance just on the thread to hold the thing together.
  20. Some of them do, either a third linear axis or a controllable focus. The cost of another stepper motor may be small, but there's also the cost of the leadscrew, rails/linear bearing, a third motor controller, a home/position sensor, extra power requirements, the extra space required... it all adds up, especially in a market saturated with bargain-basement penny-shaving designs sold at razor thin margins. The better designs have a height adjustable bed, which must really cost.
  21. There's both a functional and an aesthetic element to deciding stitch spacing. I come from a background in the English saddlery tradition (though I'm no saddler) and prefer fine stitching -- starting point is 8SPI (3mm spacing) with 18/3 linen thread in a slanted, non-grooved stitch made with a diamond awl. Either single-needle back-stitch or two-needle saddle stitch. Anything coarser is for very heavy or rough-and-ready use. Western saddlery tends to be somewhere around 6-7SPI (4mm spacing) as standard, a chunkier thread (say 18/5 linen) and may or may not be grooved by default. The modern fashion is chunky synthetic thread at very wide spacing, often 4SPI (6mm spacing) or wider and using round holes, all because the results are easier/faster but to the detriment of longevity, strength and (IMHO) good looks. The general rule is that the thicker the total thickness of leather you're sewing the wider your stitches are spaced, and so the thicker thread you use. When stitching across a strap every stitch is a weakness (like when they perforate paper for tearing off a coupon) and is generally best avoided. Where it can't be avoided (like a cartridge loop) it's best to keep the stitches as widely spaced as good design allows -- maybe 4-5 stitches per inch (5-6mm spacing). Alternatively you can use a rivetted or a laced style of cartridge loop to avoid stitching altogether.
  22. That looks great, very clean and ready for another 50+ years of use! A servo motor is a good shout, and clutch motors are great for workshop projects like burnishers or disc sanders.
  23. You wouldn't be the only one of us two to mix up the 21 and the 25
  24. I /think/ I understand what you're asking but not entirely sure. I would skive a long taper to a feather edge on the inner (orange) part, glue them perfectly overlapped (so the thickness is consistent all the way round) and then do the same with the outer layer, offset from the inner overlap. Contact cement will stop the ends of each strip from migrating. That or skive a half-thickness step, sew them grain-to-grain half the width of the taper back from the edges, and fold the unsewn ends of the taper back, with a little glue to keep the ends down. If you don't want to skive you've got two approaches. The problem you're getting is that you have two 90 degree ends meeting at an angle. One approach is to calculate that angle (some basic trigonometry) and cut the ends at half that angle so they meet neatly. Your inner leather looks chunky enough that contact cement should stop it from shifting left and right before applying the outer layer but can't be relied on in its own right. The other approach: my wife and I took a one-day jewellery workshop to make each others' ring from bullion strip. We were taught that the soldered seam has to have the square ends of the strip meet straight for a neat joint, so we bent them to a D shape with the joint in the middle of the straight. Then once the joint was soldered and dressed we made them O shape again on a mandrel. You could try that with your inner layer, there might just be enough surface area at the butt joint for the contact cement to hold and pull the edges to the right angle as you pull it round. Then once your outer layer is glued on you should be golden.
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