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Prostheta

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Everything posted by Prostheta

  1. I hadn't quantified things like how much frets spread out sideways, so calculated sizes seemed less than useful. Turns out it's a great way to do things. I'm sure calculating for a multiscale would be a little more complex. I can already imagine how to do this in CAD of course, which implies how to approach it mathematically. The angle of each fret and how the circular end meets the fretboard edge at a (secant?) is way more complex than I can remember or re-remember how to approach. This fretjob has put all kinds of silly ideas in my head. One being how to make a fret grinder using a slow dressed grinding wheel, a DRO made from a set of digital calipers and a gear-reduced leadscrew advancement. Also, a mini cutoff chopsaw for cutting fretwire to length cleanly. I think too much.
  2. I am presuming that this finish is an oil/varnish mixture which is "sort of" an oil. These need to be left for the solvents to escape, and often they get trapped under a skin of dried finish film so stay soft for a very long time. Generally they're best wiped on, left to permeate the surface of the material and then wiped off. Subsequent coats are thin and numerous as opposed to a few thick coats which results in the tacky or soft "floating" surface. I am doubting that it is a wiping oil/poly mix. What product are you using? I might suggest that if it isn't too late, taking an appropriate solvent and going back to the initial stages of the finishing process. The finish will stay sticky for forever and a day until those solvents can offgas. I'm of the same opinion as @Bizman62 here. It's worth going back and re-doing things with a slower schedule, especially if your weather isn't conducive to swift cure times. An excellent finishing article to refer to on this is one by @Andyjr1515 here: ....whilst Andy's article is about varnishes rather than oil/varnish mixtures, the technique and general approach is good grist for the mill. Additionally, refer to Bob Flexner's article on oil finishes to better get an idea of how the product you're using works in principle. http://www.woodweb.com/images_forums_public/finishing/Oil_Finishes__Their_History_and_Use_Bob_Flexner.pdf
  3. Oh for reference, I am using an orange-handled Hosco TL-FF2 crowning file, and using the medium side rather than large. Fretwire is Jescar EVO 57110. The medium size is perfect for producing easy round ends on this size of wire. I think I want to get a diamond crowning file at some point soon, mostly because steel fret files often leave chatter marks that need additional work to remove. I'd rather use both than just the diamond file on its own (diamond shouldn't be used for shaping, only refinement) so it's a complimentary tool rather than an upgrade as such.
  4. What we can take from this, is that the individual pieces of fretwire can be presented to the fingerboard after the initial end rounding has been carried out and again immediately prior to inserting the fretwire in order to ascertain whether the length is dialled in correctly. Doing this visually is sufficient, and beyond that it becomes a case of your eyes being the judge. Of course, we can still take the fingerboard width, subtract the space we want to ease the edges by and measure the fretwire with calipers. I think it would be reasonable to produce a spreadsheet of derived values for this purpose if one doesn't want to constantly measure to and from the workpiece. That depends on how confident you are that the numbers reflect reality. Okay, let's crack on. Those last twelve frets aren't going to finish themselves!
  5. Oh well. I ran out of beermats and patience, so I took to CAD. I drew a circle of radius 12" and trimmed it to an example width of 50mm, giving me an arc length of 50,056mm. I then drew an arc with a radius of 16" and an arc length of 50,056mm, aligning this over the trimmed 12" circle's arc. This shows exactly how much wider the segment becomes when the radius is flattened out by 4" for an equal arc length. This is simplifying the issue for sake of illustration. I take 0,5mm to be my "acceptable margin" below which it requires physical measurement that the eye can't easily discern without distinct reference. If you can't see the difference that easily, you're far more likely to be chasing a ghost in the numbers that you'll not see in the finished item. Unless something in the finished item specifically highlights errors in measurement of this magnitude, we can look at shorter and simpler methods. Basically, fret expansion isn't anything to be concerned about. At least, not at these fret widths and radii. The values may change more significantly at say, 6" radius flattened out to 7,25".
  6. I also did a little thinking on how to calculate the amount that a fret would expand sideways when pressed or hammered into a fret slot. I've not done the mathematics on this yet, however I know what I need to calculate. Let's see if I don't make too much of an idiot of myself here. So, the variables we have are the width of the fretboard at any particular location, the point to point distance we want the fret to lay from that edge, the pre-bent radius in the wire and the target radius when the wire is located. The value we're deriving from all of this is the point to point width of the wire in it's pre-bent radius. In more mathematical terminology, we're wanting to know how a change in the segment height affects the chord size, and calculating that backwards to figure out how wide the piece of fretwire needs to be so that it expands outwards to the correct size. I'm sure that it will be minimal, but let's play.
  7. Thanks Andy! This post is somewhat of a recap or addendum to the tutorial I did on semi-hemi fretwork: Over time and heavy repetition, methods refine themselves. I tried the method shown in the YouTube video linked previously, however I found that the wheels used were absolutely inadequate. The best way for grinding fret ends in this manner would be to use a slow speed wet grinder, such as the back end of a Tormek grinding wheel. I'd love to invest in one of those, and I'm sure that the wheel would last me over a decade with occasional use before it got to the point of being useful for fretwork grinding! If I do Tormek my life, I might ask around some tool-bod forums seeing if any Tormek owners have old wheels on their last legs they would sell. Anyway. For this build, I cut all my fretwire pieces largest to smallest. My cutters are a bit crap, so some ends mangle a little. Hardly an issue when the tang (most easily mangled) gets cut back anyway. A pair of needle-nose pliers pulls off the corner of a bent tang when straightening it, with modified nibblers as fret tang cutters undercutting the rest. If any pieces ended up too short for that fret position, they easily work for lower frets. My first job is to clean up the fret end flat using a file, and using a diamond needle file to smooth any remaining tang. This removes any chowdering left by cutters, and allows the crowning file opportunity to work evenly from the get go, rather than it having to chew off one corner more than another. After the end is clean, flat and even I run the fretwire against the file in my left hand vertically, with strokes about 45° either side in order to establish a round end profile. Having my bench against the window makes this (and most other) work quick and simple to observe. Once the fret end is rounded, I repeat this operation more or less equally with the fretwire held at 45’ from the file face, rolling it over 45° either side, being careful not to take too much from the edge. This is intended to make a 45° sweeping face that tapers out at the edges. The last of the filing with the crowning file is to smooth out those last two edges a little at around 22,5° and (hold up whilst I think...) 67,5° similar to this: At this point I either spend a little time fettling with a diamond needle file or move straight to polishing. This is where I depart from the method displayed in my original semi-hemi tutorial. Instead of drawing the profile back over a sanding sponge, I cut the profile with a felt pad in a Dremel tool. I use Autosol, which is a paste of aluminium oxide. You can also use the various white wax metal polishing compounds out there. They're all aluminium oxide and good for the purpose. Autosol needs spreading into the wheel otherwise it sprays a bit, but hey. This felt wheel was one of the (about) 1/2" wheels that come with most Dremel sets. It's done half the fretboard already. Compare that to sanding sponges which tear up and still need polishing. A smart person would have put some masking tape on the bench. I am however, not that smart right now.
  8. Whilst not quite original as such, I prefer the look of the exterior surface of the main cambium with its pins and textures. Almost like the "shore" of the river table idea. This approach turns otherwise unusable waste material into something interesting and compelling. As long as the underlying mechanics of the guitar are valid, this is something I'd love to try. It just means taking a pressure washer to blow the exterior layers off (unless maintaining those) and drying for a good long time. Plenty of pahka on Tori....
  9. I can think of a few ways, but all come down to what tools are on hand. Cutting a slice sounds good, and it can always be dressed down to the right thickness and/or taper using sandpaper taped to a flat surface. When you say 2x4....I'm hoping that's from a hardwood rather than say, Pine/Fir, etc? Those would still beat putty, hands down, however a matching hardwood is the gold standard. If you simply don't have a piece on hand and you can't get ahold of a piece of constructional veneer (the thicker stuff) I'm certain another stateside PG member might be able to help out.
  10. If you are painting solid over the top, Maple is easier. Otherwise, stick with the same material. Usually whatever you have to hand is best, to use an old maxim. Veneer is still wood, but that would need pushing in the direction of the grain from the neck so it doesn't fold up and crack. Maintain the same grain direction as the body. At this stage, anything is better than putty. The flush cut saw might work if there is no set to the teeth, and you wrap tape over the teeth and on the neck. Not so much that the thickness deflects the blade, but enough to protect. Given your patience and success thus far, I think you'll get it right with forethought. It's always the way forward!
  11. Isn't it more like a catalysed polyester casting resin, so a lot more chalky than epoxy?
  12. Great seeing you back! It's looking good, and it's always a positive reinforcement to get sound out of a build. I'm watching the video as I type this, so I hope you've not yet filled that gap in the neck. If you have the opportunity to do so, shim it with a sliver of wood. I'm sure that the wood glue already added will complicate this of course, as the internal gluing surfaces will be sealed by the existing glue making additional adhesion a magnitude less strong. The SG design has very little sidewall support as it stands, and the last thing needed at this stage is any funny business happening in the pocket. Wood putty has zero structural strength for shoring up these gaps, so it's worthwhile providing that joint the best stability it can get. In the playing position, the neck has a degree of twisting force in the pocket and if you're the sort of player that uses the natural flex of the guitar to induce vibrato, this will more than likely become a problem. If you have the confidence to do so, I'd suggest sliding a saw into the joint to both open and clean it out for a shim. It's risky though as you would expect, especially if the saw teeth scratch up the neck as they run parallel to it. Perhaps the most usable option would be to inject the gap with a hard setting epoxy (not epoxy glue) such as West System (105?) or similar. It's great for gap filling and provides the best support as a simple fix. It's already a far better instrument than those kit makers intended it to be. Your structured and planned approach makes all the the difference....I've seen overly-enthusiastic learners blow hundreds on expensive exotics and end up with a poor end result, or just trashing the lot. Being able to make a good instrument from basic materials - kit starter or not - is far more impressive. Stay safe!
  13. Well, that turned out to be a waste of time and money. I decided to try out Highline Guitars' method of taking a Dremel impregnated rubber polishing wheel, dressing it with a 3,0mm/0,125" diameter diamond ball end bit and making semi-hemispherical fret ends that way. As with most information on the Internet, this method is a bit hit and miss. I found that the dressing of the polishing wheel is very inconsistent. Once the edges thin out, they happily flop over and make it difficult to centre the profile of the fret you're working. It gets you some of the way, however the fine tuning ends up going back down the route of the method I've always used, and that's to "drag" the fretwire over an appropriately-sized crowning file, with each stroke starting almost parallel and ending up at 90°, then doing smaller strokes of the same to establish a hemisphere around the fret end. The most I got out of this technique is that I cheaped out and bought a set that included the correct arbor for the abrasive wheels and ended up with some compressed felt polishing mops which are great for polishing up a fret end. First fret. If you look closely, you can see my reflection in the fret end
  14. ....aaaaaand we're back! The move was fair uncomplicated and it feels great having space plus a lot more organisation to get stuff out of the way. The next job on this bass is to get the fretwork sorted before gluing on the wings. Believe me, that second part feels really tempting right now. Being able to see more of that finish line is a positive reinforcement that will just complicate jobs like the fretwork! Currently hunting around for a non-crucifyingly high price on a 3,0mm diamond ball end Dremel bit and silicon carbide impregnated wheel for doing the fret ends. Meanwhile, the frets have been cut to length and are ready for a bit of de-tanging and grinding to better lengths prior to the end finishing. We're getting there. I also located my camera battery charger, hence the silly bokeh off my fave 50mm lens. Thanks as always go to @Andyjr1515 whose help in getting me this Evo wire at a less-silly price was very very welcome. Its made all the difference!
  15. Looking forward to it! Now I'm starting to establish a more permanent "owned" space to work with, I can consider acoustics myself. Looking at ideas slightly left of centre are always good grist for the mill, and help develop or inspire ideas. I've two acoustics still from the many over the years, and I have a good idea of what I want to try and voice from my own. I'm sure it'll be a few lifetimes of learning to take on, but hey, nothing else better to do these days, eh?
  16. It's incredibly satisfying and validating when you discover either a great personal way of working, or that your own internal deliberation brings you to the same conclusion as an established method. Ripping up the rulebook is one thing, however it depends on whether it's proscriptive (eminently rippable) or solid reference (oh hell no). Also, try using magnets to locate items through the soundboard. They also provide light clamping.
  17. I'll see your TFT and raise you one Loverboy!
  18. Love that headstock. It's got a nice level of proportion and balance to it. Reminds me to a degree of Ibanez' Soundgear bass headstock, which I've always liked. I'm sure we've discussed this previously - if briefly in passing - but isn't that a Veritas spokeshave? I'd love to hear your thoughts on that tool. It'd be a nice upgrade from my pair of cheesy Stanleys.
  19. Yes, it's problematic. For one, colour matching becomes that much harder, for example in a simple Shaker door with two horizontal and vertical pieces. It looks different from different angles, especially with the 90°-oriented parts. I personally wouldn't go as far as calling it a fault, however when buying graded clear lumber it could be interpreted as such. As a material product it doesn't serve the end use, hence it is (I almost started describing this in Finnish) faulty or an exception that should be excluded. Generally it's not wasted, that much is a different matter. Calling it faulty doesn't mean it gets binned, it's simple faulty for that graded level of fault-free lumber. It's hard to work with in comparison to straight-grained clear wood, so the working methods need to change. Even if it could be "gotten away with" in the end product, the working methods familiar to clear wood processing may not apply. It's a pain to plane, joint and shape thanks to the grain dipping in and out of the surface causing nice clear paths of short grain where cohesive strength drops below the point where cutters shear material, and instead push it free of the rest. It's just wordplay for the most part, or at least our part. You wouldn't need to regard it as faulty unless you specifically ordered clear straight-grained lumber.
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