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#31
10-17-2023, 05:26 PM
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 Is it the same for the ones I posted in the last few days? From 2nd October onwards they should be re-sized to ~500 x 300. The ones in the posts before that are original size though. I think I've been spoilt by forum software that handles the resizing - not sure if I can edit. Andy [Seems I can edit, so will go through and change the images - thanks very much for letting me know.] [Edit 2: all the pictures should have been re-sized now - any better?] Last edited by misterg; 10-17-2023 at 06:00 PM. 
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#32
10-17-2023, 06:39 PM
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I have built 6 guitars using a very similar, if not the same, Martin style heel. 2 are from the Grellier OM plan. It is 1' wide at the heel cap. 5 of these use a 7/8" x 3" tenon, one, a Terz, a shorter one. Those all use 6mm inserts,18 or 20 mm long. They look like this.
 . The pilot hole for my style insert is more than 3/8" diameter, maybe an X bit, depending on the wood hardness. Practice on scrap. I also trickle some super glue around the insert after installed. I cannot imagine them coming out easily. My tenons are 1/2" to 7/8" deep 3/4" is good.I have tried the barrel bolts and they work but I find the inserts easier. I make my end blocks after the sides are in the mold so I can fit them to the sides. I cut the mortise after the box is closed. But you've already done your's so you should be ok. Good luck
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#33
10-17-2023, 07:00 PM
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__________________
Fred
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#34
10-18-2023, 03:25 PM
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Quote:
 I'm not wedded to the detail of the plan, but it seems a decent place to aim for. The inserts I had found were similar, but only 10mm or so long, which I didn't feel was enough. Longer ones like those could be bedded quite deep into the heel, so I think they could still be an option, even without modifying my current head block. Thank you both for your interest and encouragement  Andy
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#35
10-19-2023, 06:12 AM
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You could always try making your tenon thinner and test fit an insert into a piece of scrap to ensure it doesn't split.
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#36
10-19-2023, 07:50 AM
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I have a 16mm mortice currently (that could be made bigger). I'd probably try and drill / fit the inserts before cutting the cheeks of the tenon away in any case. I'll get hold of some of the longer inserts and have a play on some scrap.
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#37
10-19-2023, 08:13 AM
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I don't install my inserts before cutting the tenon because my tenon template is attached to the neck with drywall screws into holes which are later enlarged for the inserts. You're method sounds intelligent though, if you have another way of doing your tenon.
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#38
10-28-2023, 06:20 AM
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I had cut the sides to the template in the plan, but had added a little material to each side 'just in case'. Marking the finished height of the top of the sides was easy by laying it on a flat surface and marking around level with the head and end blocks
 It was pretty much all of the 3mm extra I had allowed. Marking the finished height of the back was a bit more of a puzzle. I was avoiding making a radius dish, and had read up in the Cumpiano / Natelson book about using a sanding board to shape a radius on the back. Faced with the reality of this (and the need to make a large, flat sanding board anyway), I caved in and made a jig to carve out a rectangular radius dish!  I made it out of 18mm MDF, but after cutting the dish, the board became very flexible and the edges bowed up, so I had to glue it down to another piece of MDF to stabilise it. The whole thing only took a couple of hours, including making the jig. This is the back sitting on the radius dish before any adjustment - they're actually a reasonable fit. If I'd only added (say) 1mm to the sides, I'm sure they'd sand down to a fair curve quite easily.  As I had added more material than that, the radius dish provided a reference for marking the finished height of the sides at the back of the guitar. Again, this was pretty much all of the 3mm I had added on:  Both edges of the sides were planed back to the marked lines (quite enjoyable work).  And then the back was worked against some sandpaper stuck to the radius dish to level out the cut.  For the front, it was necessary to use a sanding board as the inner parts of the head and end blocks stand proud of the sides:  It was about now that I noticed there was a crease / divot in one of the sides around a patch of funky grain - I made a separate post about this, but the upshot was that I was unable to get rid of it by heating, so ended up fitting a doubler to the side in this area to try and support it, and bring the distortion within 'sandable' limits.  It has helped a bit  Andy Last edited by misterg; 10-28-2023 at 06:28 AM.
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#39
10-28-2023, 06:58 AM
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Firstly, I will apologise in advance for being a newbie and heading off piste: I really wanted solid linings in this guitar. I know kerfed linings are traditional and perfectly good, and come from the peones in classical guitar construction, but aesthetically, *I* don't like them - they always look 'unfinished' to me. If it ends up sounding like a banjo, I'll only have myself to blame!
I had bought some 6mm thick lime wood strips (similar to basswood, I believe) for the linings, and rather naiively set about trying to steam them to shape (they didn't want to know about bending on the hot tube). I made a makeshift steamer out of some insulation board that worked very well.  I also made a couple of undersized forms to bend the linings around. For my first try, I soaked the strips for 2 days and then steamed them for 30 minutes. They certainly became very pliable, but wouldn't hold their form when released from the forms a week, or so later.  Also, in the tight curves, they wood developed ugly creases  I had read about basswood wood 'collapsing' if over soaked / steamed, so, assuming that lime was similar, I tried again, reducing the strips to 5mm thickness, and steaming them for 15 minutes without any prior soaking. They at least held (most) of their shape, but were still pretty ugly:  With that out of the way, I decided that the way forward was to laminate the linings (in the manner shown by Beau Hannam's videos on Youtube). I reduced the strips to 3mm thick using my hand planer on a bench mount (Bosch used to sell a similar adapter - this is my home made version):  These strips bent easily on the hot tube with just a spritz of water...  ...and held their shape well:  Two strips were laminated in-situ, clamped to the sides   For the back linings, I used strips of rosewood left over from the sides. For reasons even I don't quite understand, I included a layer of maple veneer in the lamination.  Once the glue had set, I cleaned up the inner edges on my belt sander  And then cut a radius on the inner corner using the router table  Mmm... I like that maple.   Full set of linings  Next job is to sand the inside of the sides and then fit them.
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#40
11-06-2023, 04:33 PM
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Fitting the top linings seemed to go OK - I mostly used clothes pegs with rings of bicycle inner tube wrapped around them, but made a couple of matched cauls for the tightly curved areas around the upper bout and waist
 When the dust settled, however, I could see a slight gap in a few places on the inside edge of one of the linings - it had all been tight when I dry fitted it. on the outside edge, the joints were all pretty tight. Poking about with a feeler gauge showed that the gaps weren't actually all that deep:  The worst bit was on the waist which went in about 3mm  The first lining I did was pretty much OK. I think that I'd overdone the initial clamping of the second one, and it couldn't 'find its place' as I clamped the full length and I made the mistake of trying to ease it into position. I wicked some medium viscosity CA into the gaps to fill them up and to maybe reduce the likelihood of future buzzes, etc.  Lesson learned, I fitted the back linings with clothes pegs along the full length before clamping anything up, and let them go where they wanted. Joint wise, I think they came out perfectly, inside and out.  They did end up rising up above the sides at head an tail, so the linings will end up quite short here, but I guess will still do the job.  With a freshly sharpened block plane, it was an absolute joy to plane the linings down to within a hair of the sides.   I love the pinstripe shavings! I levelled the top linings and put a slight bevel on them with a radiussed sanding stick - I used the 25' radius for the lower bout and the 15' radius (that I'd made for the back) to do the steeper curve at upper bout around the head block and fretboard extension. (I may need to refine these when I come to fit the top.)  The back was levelled with another 10 minutes on the radius dish. It all went very quickly.   continued...
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#41
11-06-2023, 05:02 PM
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...continued
To mark the brace positions on the lining, I copied an idea from one of Marshall Brune's videos and made a very thin marking knife out of an old hacksaw blade   I used a gauge on each brace in turn to set the depth of the router cutter.  I used a thin shim (coke can) when I set the depth to reduce it very slightly to keep the joints snug.  I fitted a piece of ply to the router to act as an extended base and just free-handed the bulk of the material out before cleaning it pocket up with a chisel    I was very pleased with the result:   I hope they glue up as nicely. I did have one minor disaster - You know that thing about never lifting the router up until the bit has stopped spinning? Yes, that one. I just caught the edge of the lining and took a short section of the corner off. It's just to the right of the brace in the photo below. Apart from feeling silly, I don't feel too bad about it.  I thought I would fit the end graft now, as it seemed to be easier before the top of back were fitted. I decided to rout it out as I find it easier to get a nice, clean edge and even depth that way. So I cut a pleasing looking taper out of some maple and cobbled up a jig from some scraps to match it.   At the last minute, I remembered that I wanted to add purfling strips either side of the wedge. I thought I had bought strips that matched the white-black-white-black ones already attached to the bindings, but aparently not... So I had to plane a couple of lengths of binding down to just leave the purfling.  After glueing and scraping it back, I think it came out OK:  Thanks for reading Andy
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#42
11-17-2023, 05:18 PM
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Gluing the back on (probably too much glue). The spreader is only loosely in position.
 The strips of innertube and bungy cord wrapped around drywall screws did a great job of holding the joint tight and allowed complete access to the inside to do the cleanup.  Still some sanding to do, but very pleased so far:   I didn't feel ready for finishing the carving of the top braces, so pressed on with the neck instead. I thinned the blank down a bit before gluing the scarf joint. After cleaning it up a bit:  I did order some threaded inserts to see how they would pan out for the neck attachment, but despite them being described as steel (two separate suppliers), when they turned up both lots were some sort of cast zinc. I was concerned that the threads might get chewed up easily (I've damaged enough of them over the years) so I decided to stick with my plan from above, and drilled the holes for the vertical dowel and the securing screws. I needed to drill the dowel hole before routing the truss rod slot (because they intersect) but, in hindsight, it would have been better to delay drilling the screw holes until I could put the neck in position and mark through from the headblock. I went around in circles trying to think of a clever way to cut the tenon (router, sliding mitre saw, etc.) but in the end I just used a dovetail saw for the shoulder cuts and the bandsaw for the cheek cuts. I aimed to angle the shoulders in slightly per the Cumpiano book.   One side is cleaner than the other - I guess I can put whatever time it would have taken me to build a router jig into finnessing the hand cut joint. Time will tell... I wasn't keen on the headstock outline in the Grellier drawing, so doodled around and came up with something I was happier with that geve a slightly better string angle to the tuners. The shape looked OK on the rosewood headplate blank inside a paper cut-out  So I cheated and used my little CNC to make a routing / drilling template out of 3mm ply  (There are a couple of sets of holes on the treble side as I was still toying with an asymmetric layout.) I bandsawed a quick-and-dirty dummy headstock out of a piece of scrap 12mm ply to see how the tuning machines fitted and to check for clearance.   The symmetrical arrangement seems to fit fine - Decision made! Just got to make the real one now! Thanks for reading
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#43
11-21-2023, 06:23 PM
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Well, the phase of the moon was right, and the mojo was high, so I decided to work on the soundboard bracing.
I am only 'painting by numbers' here, so my aim was to match the dimensions and shapes in the plans and make it look as neat as I could. Unless I hear different, this is "it":     The top is still ~~10mm over sized (the pencil outline is roughly right) and the transverse brace and front ends of the X braces need trimming. If anyone has any comments, suggestions or critique please speak now... 
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#44
11-26-2023, 05:57 PM
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Dearly beloved, we are gathered here today to join together... etc.
 Some odd jobs to finish first: The nice, new Forstener bit that I had ordered for the tuning machine holes turned up - I think the packaging must have cost more than the bit!  I used it to drill the truss rod access hole in the head block. I was originally intending to rout a slot for it once the top had been fitted, but with a clearer idea of where it would end up (after starting the neck) I realised it could be below the top completely.  Next job was to align the top and mark and cut the ends of the braces and the mortices for them in the lining. I'm only setting the upper transverse brace and the top ends of the X braces into the lining. The lower ends of the X braces will be pared down and clamped between the lining and the top, and everything else will be shaved to zero thickness before they meet the the lining. The top tempararily lined up on centre and clamped in place:  I was intending to use the rubber strap to wrap when gluing the top, but a) it wasn't anywhere near long enough to wrap round and around the body; and b) it was a PITA to put it on and off when test fitting. I made a couple of spool clamps to help, and having used them, made up a couple of dozen to use for the glue up. I marked the ends of the braces for trimming, and used the same, thin, marking knife that I had used for the back to mark the position of the braces on the linings.  I used the trim router to remove the bulk of the material from the brace pockets, as for the back, and finished up with chisels and a modelling knife. I think I managed to get reasonable fitting joints on both sides (as judged by poking a phone camera into the sound hole:   I did go around with a 0.05mm feeler gauge to find any gaps and then carefully sanded the braces to get them fitting tightly. I found I also had to finesse the transition between the head block and the sides to get a tight fit - the plane was only taking off dust, but it made a difference.  I finished off the top of the tail block to give reasonably consistent gluing width to that of the linings  I also marked the body outline on the top and trimmed it to a little over the final size, and did a whole bunch of sanding on the inside of the body... ...and made cauls to fit under the bridge and fingerboard extension for use later   I've also gone down the rabbit hole of 'popsickle' braces... There isn't one shown on the plan, so I don't think one is needed. Just in case somebody tells me at a later date, I cut a piece of spruce that could be used as a brace in this area, just to keep in my back pocket, so to speak.  Deep breath, glue bottle out...  I did use the rubber strap to fill in between the spool clamps on the lower bout, but this was only a bit of insurance - I'm pretty sure the joint was tight without it.  A quick run around with the trim router, and we have a box!  I'm pleased with that!
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#45
11-28-2023, 12:57 PM
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I tried to plane the headplate down to thickness by hand, but had to admit defeat - it was like cutting down the legs of a table; I was just chasing uneven thickness around the piece, and rapidly running out of thickness (I was aiming for ~2.5mm).
So I swallowed my pride and thicknessed it on the CNC  I also cheated and cut the mother of pearl inlay and its recess using the CNC  (sorry to craftsmen everywhere). I had never tried to cut shell before, let alone with a 0.6mm bit, but a video on Youtube by Brian Right was extremely helpful and I managed to cut the complete inlay without breaking anything. ( https://youtu.be/e5Wao5huZnA?si=bn4c0PRPvRZpB7c3 ) I used the same bit to cut the recess in the headplate  The beauty of having it on the CNC is that I could re-cut the recess, gradually increasing the size until the inlay slipped in.  I glued in the inlay and sanded it back, then tried to glue the headplate to the neck, and messed up: I wasn't really thinking, and used a soft, cork covered caul to clamp the thin headplate. The (oversized) headplate bent around the the edges of the headstock, under pressure from the (also oversized) soft caul. This caused the headplate to lift slightly near the edge of the headstock:  I managed to rescue it by going over it with a household iron until the glue softened (titebond) and re-clamping it. When I trimmed the headstock, the offcuts still seemed to be stuck, so hopefully I've got away with it. The final shape was machined using a template following bit in the router:  Followed by drilling the tuning machine holes  It still needs a little bit of filling around the inlay (there are a few pits in the glue), but I'm pleased with how it came out. My original intention was to chamfer the edges of the headplate, but I haven't decided whether to do this or not, yet.  Now I must wrap it in padding so I don't keep banging it on things! Thanks for reading
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