Prostheta Posted October 8, 2016 Author Report Share Posted October 8, 2016 Me too, @Chris G. I'm laid up with that terrible illness going around and can't find the space between work, passing out and coughing my lungs up to do anything.... Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 18, 2017 Author Report Share Posted June 18, 2017 Seriously.....? I haven't posted anything on this one since late last year....? Wow. Okay. Let's get up to speed. The wings were attached using a broadly similar technique to the headstock, albeit with a flat plywood board underneath the body, two 16mm plywood risers supporting each wing and two (for want of a better name) overhead parallel clamping cauls over the top.... On 6/11/2016 at 6:20 PM, Prostheta said: Two U-shaped cauls made from plywood or whatever keeps its dimensions nice and square. I simply ripped a strip of waste plywood to about 35mm-40mm wide, then cross cut it on the table saw into 4x 50mm plus 2x 120mm lengths. A dab of glue and chamfering the "pad" faces produces an excellent pair of headstock alignment cauls. Chamfering is not 100% required, however I don't like corners. Total paranoia, I know. The exact same idea helps with the body also. Like I stated, this idea helps with the body! In order to increase positioning accuracy, I glued one wing first of all and used that as a reference for the second. Titebond-I has a reasonable working window where you can position a piece freely and after it starts to grab, clamp it closed for a clean glueline. It's about 22-24°C in summery Finland right now, so glue is drying nicely without the crazy dry winter thing of it going off on you in a heartbeat. The upper wing had glue applied (excess wiped off with a squeegee to reduce squeezeout) and the mating face on the neck wiped with a damp cloth to provide an easier wetted surface for glue to migrate. After positioning the wing and allowing it to grab under its own gravity (five minutes or so) clamps and cauls were added for it to dry overnight. Two big Bessey GZ40 clamps are all it takes to provide adequate clamping pressure by the numbers (6000N each, or about 1348lbs force). Why am I detailing the exact models of clamp I used? Advert for Bessey? Not quite.... The mating glueing surface of the wing was about 350mm x 35mm or thereabouts. That's about 19in². If those clamps were whaled up tight to the point where the bar deforms, the glue joint would be under about 141PSI. A bit short of the general recommendations, however in conversation with the technical manager at Franklin it appears that loose is no big deal in anything other than the cosmetics of the glueline itself. The ultimate bond strength of two well-prepared mating surfaces will be far higher than is required in a bass, so it's all good. 1 Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 18, 2017 Author Report Share Posted June 18, 2017 So after the first wing was glued up and dry, it provided reference for the second wing in the clamping jig so that both wings are co-planar with each other. The neck itself is left proud front and rear, so that now needs to be planed or otherwise made flat with the wings.... Two small strips of plywood with 3M double-sided tape at either end make perfect temporary rails for a router to plane the neck flat: The sled for my compound neck scarfing jig is easily repurposed for this work.... A large 19mm flat-bottomed cutter should make this job light work.... 1 Quote Link to comment Share on other sites More sharing options...
Andyjr1515 Posted June 18, 2017 Report Share Posted June 18, 2017 I spotted the chamfer on your ply jigs! It isn't just that they're chamfered....it's that they're so perfectly chamfered . It does your craftsmanship credit. It's great to see this back in progress. I need to remind myself, when I'm on a faster connection, the design features. In the meantime, you've given me some thoughts how I get to be able to rout the hatch rebate on my new bass build....except my jig probably won't have chamfers. Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 18, 2017 Author Report Share Posted June 18, 2017 Thanks Andy! The chamfers are simply because I don't like hard corners on jigs where they come into contact with a workpiece. I even put a single layer of masking tape over the pads out of protection. The wings are already finish sanded which is far easier off the neck. The jig ensures accuracy up to how well the wings and body were jointed, so it really is a successive chain of events....or maybe more like a house of cards if I screwed something up waaaaay back down the line. Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 18, 2017 Author Report Share Posted June 18, 2017 A few passes, then a quick chase with 180 grit. The first two passes were made to get rid of the majority whilst the last was measured to cut at the exact depth as the plywood rails are thick....the addition of the double-sided tape under the plywood ensures that the cut is microscopically shallower than the final depth, so any slop or play is easily dialled out in sanding. The heel looks ugly as sin, and needs finessing to a smooth circular end. I could relieve it all the way back to the body, however that chunky heel is a signature Rickenbacker thing so I'd like to keep that. I'm of the opinion that the more mass remains in the neck (as opposed to making it long, thin and more flexible), the more sonorous the neck will be. This isn't backed up by objective fact, however being as far from rubbery necks as possible is always a good thing. Access is not an issue because bass. Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 18, 2017 Author Report Share Posted June 18, 2017 It then becomes a case of rinse and repeat. The riser near to the end of the neck was maintained, and will be trimmed with a chisel once the fingerboard is in place. 3 Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 18, 2017 Author Report Share Posted June 18, 2017 I'd better ask to see if I can borrow a pyrography pen now.... Quote Link to comment Share on other sites More sharing options...
psikoT Posted June 18, 2017 Report Share Posted June 18, 2017 Did you flat the top and back with the orbital sander?... should I buy one of those? I'm sick of doing it by hand, using a "flat" surface covered with sand paper. Great work btw, love this one. Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 18, 2017 Author Report Share Posted June 18, 2017 Doing it by hand is just as good if you're using a hard flat block and check your progress. A good random orbital sander can be costly (the DEROS is getting to around €450 for the 5650CV set however I use the 625CV which is around €300 depending on where you buy. They're all the same sander, with the numbers specifying pad and orbit size. I've stuck with the DEROS simply because I have about six years of hands-on use with Mirka sanders, and I haven't found anything which is anywhere near as handy and useful. Makita and Bosch make models a fraction of the price, however I find them too tall and tippy and are more prone to jumpiness, leaving swirl marks, etc. http://www.axminster.co.uk/mirka-deros-5650cv-random-orbit-sander-503855 Sanding by hand is always the safest and most controllable option of course. I'm of the opinion that a finish sander (2,5mm orbit as opposed to 5,0mm orbit) is an investment rather than just a purchase, so it's worth considering and trying out what is available. Which reminds me, I need to finish up the review on the Festool ROS sander....which isn't a tool I can recommend....still, useful info so we know what the bounds of things out there are. Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 18, 2017 Author Report Share Posted June 18, 2017 Since both wings were co-planar from the glueup and the majority of the neck tenon was brought down to the same level (within a fraction of a mm) the sander hardly needed more than 10-20s of work with 180 grit. Pencil scribbling either side showed when it was level. That would have been maybe a few minutes block sanding otherwise. Quote Link to comment Share on other sites More sharing options...
Andyjr1515 Posted June 18, 2017 Report Share Posted June 18, 2017 Some great skills on show here and some excellent tips and techniques. I'd forgotten the double sided tape technique - so obvious once you've clocked it but I could have gone on building 10 years sweating over excess sanding jobs and still not remembered to do it... ... reminder gratefully received Quote Link to comment Share on other sites More sharing options...
psikoT Posted June 18, 2017 Report Share Posted June 18, 2017 Well, that's a lil bit pricey... I think I'll stick with my arms. But good to know that cheaper ones won't do the job properly, so I don't waste any money of them. Thanks for the info. 1 Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 18, 2017 Author Report Share Posted June 18, 2017 I asked Carlos at G&W to see if he would be able to stock the 3M DST, since otherwise it's specialist stuff (coincidentally, RS sell them, Andy....) that is easiest to acquire from StewMac....but not cheap by any means. The whole "masking tape and superglue" thing still annoys the hell out of me, mostly because it's such a waste of money compared to how inexpensive DST is. That €20 roll is hardly even dented and I've been using it almost every week for both instruments and furniture work. A little goes a LONG way. The obvious alternatives to routing the excess would have been hand planing, but that wouldn't have worked out for the front where the fingerboard step is. That and one false move puts a crease in your wings! 1 Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 18, 2017 Author Report Share Posted June 18, 2017 1 hour ago, psikoT said: Well, that's a lil bit pricey... I think I'll stick with my arms. But good to know that cheaper ones won't do the job properly, so I don't waste any money of them. Thanks for the info. Cheaper ones do the job. Certainly, any random orbit is a world better than a simple rotary sander. The DEROS has its place because I know how durable they are, how much Mirka stands by its guarantees and that they just perform outstandingly. My primary issue with cheaper sanders is that the velcro pads are often not replaceable. Once you make one false move accidentally sanding without a paper attached (intern students....they do it too much) or push the machine too hard and damage the hooked surface, the machine is more or less toast. I hate tools that you can't maintain and repair. Step up to the mid-range and you can then buy new backing pads, but the machines themselves are still clumsy and feel like crap. The Bosch ROS20 range for example, are all 5" x 6" x 9" (125mm x 150mm x 225mm) which is super tall and hence bulky feeling. My DEROS is the same size but a full 2"/5cm shorter, which makes a huge difference. Kind of like a Ford GT40 versus a Volkswagen Polo. A high centre of gravity means that it's too easy to put excess pressure on the pad edge rather than a confident uniform flat contact area. Surprisingly, I felt exactly the same way about the Festool ETS EC machines and they're super expensive! The DEROS is right on the money. 1 Quote Link to comment Share on other sites More sharing options...
psikoT Posted June 18, 2017 Report Share Posted June 18, 2017 Thanks, then maybe I consider to try a cheap one, as I'd need to use it once a year... not really a high level of production here. Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 18, 2017 Author Report Share Posted June 18, 2017 You know what? I wouldn't bother at that level. Hand sand all the way. It only takes one sucky moment with a machine to alter your work beyond what you wanted. I'd rather lend you mine. When I was doing my wood manufacturing degrees I saw a lot of enthusiastic-but-inexperienced people burn through various machines, not just sanders. Schools are a crucible for hand tools and machines. Both the CEROS and DEROS units saw thousands of hours of use each year, occasionally abuse too. The CEROS died once in the third year of my first degree and Mirka serviced it. They would have done it for free (out of warranty!) but the school sent it in before I got chance to sort it for them so they paid. Meh, whatever. Beyond that, those machines saw daily work and still operate fine today as far as I am aware. The Festool tools just didn't get a look in and were all completely sidelined by the Mirka units. Festool are another story as it stands....and not a good one. For anybody that's just doing a project every once in a blue moon it's a big ticket investment, but once you start doing more than that it's a worthwhile one. You know how they say that when you buy cheap you regret it every time you use the tool, but when you buy the proper expensive tool you only regret it the once? Case in point right here. Zero regrets. I couldn't not have one in the ProjectGuitar.com workshop. 1 Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 18, 2017 Author Report Share Posted June 18, 2017 I don't want to come across as some sort of tool snob. Quite the opposite. I genuinely think that hand sanding is superior for guitar work than a mediocre ROS. I'm fully cognisant that a €300 sander is not within most people's budgets. In that respect, I think that spending €100-150 on a cheap to mid-range ROS would be better saved buying some high quality abrasive media and sanding blocks, or just saved for that better machine. I'm fearing having to buy a bandsaw for that very reason....I know that once I commit to one, I will regret not having waited a few more months to pull the trigger on something better. Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 18, 2017 Author Report Share Posted June 18, 2017 I'm not 100% convinced by the end profile of the heel..... Rick 4003s have a far less circular shape to them: There's still a fair amount of material left to draw that back and re-shape it appropriately. Quote Link to comment Share on other sites More sharing options...
ScottR Posted June 19, 2017 Report Share Posted June 19, 2017 On 6/18/2017 at 2:30 AM, Prostheta said: Seriously.....? I haven't posted anything on this one since late last year....? Wow. You think that's bad? You should see the gaps in posts my friend Carl makes........oh wait. Nicely caught up and lovely work sir. SR 1 Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 19, 2017 Author Report Share Posted June 19, 2017 Thanks Scott! It's only just occurred to me how differently the colouration of those adjacent pieces of Birch are. I'm tempted to get some straw-coloured stain mixed up.... Quote Link to comment Share on other sites More sharing options...
ScottR Posted June 19, 2017 Report Share Posted June 19, 2017 Do you have any scrap from that piece left? SR Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 19, 2017 Author Report Share Posted June 19, 2017 Of the Karelian Birch (Visakoivu) or the Birch in general? Quote Link to comment Share on other sites More sharing options...
ScottR Posted June 19, 2017 Report Share Posted June 19, 2017 Of the lighter colored piece in the neck lam. Maybe I misunderstood your comment? SR Quote Link to comment Share on other sites More sharing options...
Prostheta Posted June 19, 2017 Author Report Share Posted June 19, 2017 No, none of that left. It was taken from a pallet of A grade clear PAR Birch. Variations occur in Birch anyway so it's perfectly normal. Just surprised that I didn't notice it sooner. It may well have aged over the last year also. I should feel bad cutting into this vintage stuff. Quote Link to comment Share on other sites More sharing options...
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