verhoevenc

Hey guys. I've been doing some more tests with my CNC and wanted to share my latest fun. I had thought about doing this for awhile, but when I saw the folks at Kauer doing it I was emboldened to do my own tests. The basic principal is to mill out a channel for the binding as the very first step in the build. That way you just hammer the binding into a slot and CA it. No strapping tape; just easy. The Kauer guys gave me some great advice and said to put holes every few inches along the channel to account for glue overflow. They also mentioned they've had better luck with a bead of medium CA in the bottom followed by a thin CA flood. However, since everyone's milage varies I wanted to see how this played out on my machine. Step one was to mill the channel and the glue reservoirs. I purposefully did sections of both straights and curves. Once cut I did half with a bead of medium CA in the bottom and then hammered the binding in with a rubber hammer and flooded with CA: I then waited for everything to dry and went and cut what would have been the "body" outline with a 1/4" end mill like I would in real life: Once that was done I could bandsaw it out close to the line and do some sanding to see how everything worked out. Here's the top. As you can see both side were equally as good and easily pass quality control: Next lets look at the sanded side where I did a medium CA bead at the bottom of the channel. I feel that there is too much gap here... it's visible. This does not pass my quality control: Here is the, in my opinion perfect, thin-CA-only side: Lastly, here's where they meet in the curved section. As I expected the thin CA side is great, the medium CA side left some gaps on the bottom edge: It appears for my setup and processes that I prefer the following steps: 1- Mill channel to only .001 over the binding thickness (that plus the few thou in runout any machine has will be plenty to allow for thin CA. 2- Hammer in binding with rubber hammer and flood with thin CA. 3- After dry run your profile cuts. 4- Sand edges smooth like any binding application. Hope this helps folks, Chris

Yes, I haven't cracked MeshCAM's secret on why it only respects surfaces and polygons... not lines. One thing I'd really like to do is mill constant-depth fret slots the follow a radius. Therefore, I need to do it in MeshCAM... but I've had the same experience there as you. I plan to play around with that particular issue a bit more so I'll keep you posted. Chris

So far I'm having a hard time finding anything I'd want to do on a guitar that MeshCAM won't handle in 3D. I'm still using VCarve Shotbot edition for all my 2D stuff simply cause: 1- It's so dang easy 2- I can string multiple operations together in a single file (which I'm yet to really figure out with MeshCAM unless I want to use the same speeds, etc. for all the operations). Great thing about it is you get a free 15 day trial. I'm 5 days in and I feel I already have a very good grasp of it. It's made for ease-of-use CAM... but there's still a TON of features in the version I'm trialing (Standard, not even Pro) that are way beyond the detail I need. As for confusion... that's disappearing much faster than I would have initially anticipated! Chris

So I've had the thing for awhile but I've mostly been telling myself, "You can't play with your new toy until you finish up a few things." Well I did so I've finally been playing! Over the last two days I have cut out what I'll refer to as my first "guitar-shaped object" aka: GSO. It's just pine and for testing, but boy was it a bunch of fun! Before this all I've ever cut out was an E and a small sign with a word on it. It'd say for a first go at a GSO and my first go at 3D cuts (using the MeshCAM trial right now and quite happy) the learning curve hasn't been ass big as I'd feared. Here's the various pieces I needed: 2D top cuts went smoothly! As did the arm bevel cut with a very fine step-over on the finishing pass: On the back I for some dumb reason told the cutter to cut inside the profile instead of outside, GAH! But so far this is the only mistake: I figured why let that slow me down so I also did the 3D cuts on the back for fun and tried it with a less fine step-over on finishing: Don't get me wrong... this took hours of generating and re-generating my tools paths until I was happy. Also took several smacks of the emergency stop when I saw the cutter heading the wrong direction hahaha. But I feel like in the end everything except that back 2D cut went really well and I went from 0 confidence to like 70%! Best, Chris

Hahahaha. I wish man! You've seen the EIRW. The zebrawood has been in finishing stage for... well... 5-6 years? Lol. I lost interest in that project but it's on the block to complete. The amboyna one is in progress. Chris

If it's got striped grain I see no reason why not?! I've done stripy EIRW and zebrawood to date; about to do some amboyna burl with alternating sap/red Chris

I can't take the credit, first person I ever saw do the radial purfling was my friend Todd at Greenridge guitars. I'm even talking years before you started to see it pop up in custom builds and even mini-factories. He's one creative, and geniusly-inclined, dude! Chris

I'm in the same boat. You'll always be that person. You wait til other people think they're good enough. Hahaha. Put all the pressure on them Chris

I'll start! This was actually finished awhile ago but the customer just now got around to taking pictures. Sadly, I didn't have time to take pics of my own before sending it out, so I had to wait. This is my Model2J with some additional crazy specs: The body is a chambered hunk of "plyboo" bamboo plywood. The top is brown-dyed quilted maple that's bent over the arm contour and accented with a veneer line of wenge. The pickguard is wenge too. The neck is also plyboo reinforced with carbon fiber... it actually worked out great! Wenge fretboard with customer-supplied "sun" inlays in gold MOP. 25/5" scale with 12" radius. The electronics are two Rose humbuckers in JM-style housings with 3-way, volume, and tone controls. The rhythm controls in the upper bout simultaneously coil tap the humbuckers and mixes in the middle single coil so you can get strat 2 and 4 sounds. The volume and tone control just that one pickup and the 3-way selector still works on the now-tapped humbuckers. Hipshot open back locking tuners, limited run copper mastery bridge with matching pickup covers, and tru-oil finish. Enjoy! Chris

I sell the newer ones. Older ones that I don't think are "up to snuff" stay at home. Maybe one day I'll give them to friends? Chris

I agree in general except for the headstock part. A lot of headstock snaps (especially on LPs since Gibson/Epiphone hog out SO much material up there for the adjustment) are due to inertia IMO. By that I mean you have a fairly thin area of wood connecting the headstock and neck, and then you throw a ton of tension on it from the strings and a bunch of weight from tuners. Therefore, if the guitar falls and the headstock isn't supported, the weight of those tuners and the pull of the strings is going to increase the inertia, when the box stops the headstock is not going to want to stop, and you're asking for a break. I'm of the opinion you should put some padding around the headstock (like bubble) wrap. Don't make it imobile like the body, but give it padding to slow any movement down over a greater distance. Think of it like having car air-bags for your headstock. Chris

God I'm a sucker for Original's. Especially knowing he did those covers himself! Chris

You have access to a laser cutter!? Screw messing with the neck, re-cut the template with a wider pocket and re-route it. If you have access to that level of accuracy why not take advantage of it. Everything SHOULD line up perfectly again with lasered stuff. Chris

I don't want to hijack a thread so I will try and keep it short, but David and I still keep in touch regularly. He's been pivotal in my learning about, and recently acquiring, a CNC. I'm also hoping he'll be helping QA a new hardware design I'm having made (teaser alert!) in conjunction with thegarehanman (ya'll remember him?) and an F1 engineering friend of his he pointed me to. David is an absolute joy and a wealth of knowledge. There are 3 people in this world that I cannot thank enough for making me the luthier I am today: David, Todd (mentioned above), and Erich Solomon. 3 of the most kind, caring, and generous individuals I've ever met... especially to someone like myself who can often be a force of evil as well (look back far enough into PG history and I haven't always had the shiny rep Prostheta gives me hahaha). If you guys haven't watched Todd's video series on youtube I cannot recommend any harder searching them out (MDLuthier) if you are planning to build anything in the realm of acoustics or if you're yet to learn how to make a blade so sharp it's ridiculous: https://www.youtube.com/user/MDLuthier/videos Best, Chris

That seems easy! Can't wait for the rest of the info!! That's too cool. Chris

Please please please do tell me about this "vacuum forming of plastics" you did for the covers?! I have a copy of a Gibson V2 pickup that I'm itching to mess with that could benefit from this knowledge! Best, Chris

Lots to say... should probably make a list! lol - LOVE the headstock inlay idea. Fits extremely well! - Absolutely love the bookmatched sapwood cover to hide the join and get a wide enough piece... will definitely be stealing that! - Would you mind sharing your supplier/part number for the humbucker mounting inserts? I'm super tired of the giant-pilot-hole spiral inserts I've been using. Best, Chris

Tuning an acoustic top is really, really hard to relate to another human being... especially on a first build. However, something you said already has me thinking you're on the right path: what you said you were listening for as you carved. I call that "flutter". That wavering, responsive je ne sais qoui that a well-carved top has. However, I can give you some pointers regardless. The first of which you've already done wonderfully: 1- Keep everything in front of the X fairly stiff. There's not much the top is doing up there and stiff is good IMO. So it looks good that you haven't scalloped in front of the X, and you left your UTB chunky. 2- My biggest recommendation for you would be to make your brace carves more triangular. Stiffness increases linearly with width, but exponentially with height. Therefore, if you look at the edge of a brace down it's length you'll get almost as much strength out of something that has an arch-like profile (think the shape of praying hands almost) as you will with a squared profile. The only reason you need braces as think as people say is because you want a good glue surface. So get in there and taper! Lose that extra weight. 3- Don't think you're done tap tuning until you have your bridge plate on. You'll glue that thing in and go "holy hell everything has changed!" Remember, your other braces are fairly small, spread out, and made of light wood. A bridge plate, although thin, is a HUGE and heavy "brace" (usually maple, rosewood, something dense). I think you'll find that once you put your bridge plate on and get back to tapping you'll find you can get away with a much more aggressive scalloping scheme right behind the X. Here is a great picture for reference about what I'm talking about: Photo credit to the man that taught me everything I know about acoustics, one of the most under-rated and under-known builders, and most accomplished voicers I know, Todd Stock of Greenridge Guitars. Hope that helps, Chris

There are several builders who will take on CNC work. Several members on here. A lot of builders that have CNCs don't run them as much as they'd like, and a CNC sitting idle is lost money. If you legit have files ready, put out some feelers to other builders that you know use CNC, you may be surprised what you hear back. Chris

Side note: As a hobby "bedroom builder" I think 1-2 guitars a month, you'll find, is very ambitious! Even if just making strats and teles. Throw custom, setneck, etc. work in there and you've got to re-evaluate your business model IMO. Chris

Thistle, I agree, the large X-Carve is pretty high on the bang for buck list. I'm actually seriously considering one myself. However, I'll clue you in on some stuff that I've learned in my research of it. Firstly, it's run by belts and not lead screws for the X and Y axis. This means it's more likely to skip steps if you try and run it hard. So basically, expect to run this machine really slowly for true guitar-cutting operations... perhaps even slower than you could do it by hand for things like body routing. Go look up highline guitar's youtube channel as he has a number of videos that talk about feed rate and depth of cut for typical guitar stuff. For me, this speed limitation isn't a big deal for me since I'm looking at the CNC more as a tool to keep me productive in the winter while I can't access my giant cast iron, table-saw attached, router table. Another good idea I've thought of is to use this CNC to route the first 1/4" depth or so of anything, then pull it off, bandsaw close to the line, and use the CNC's 1/4" route as your template. CNC accuracy without taxing the run time of your CNC. Speaking of run time, don't expect to use this as a machine that will do production runs! Routers aren't made to run for hours upon hours. They like cycle time (time on followed by rest time). That's why production run CNCs have spindles, they're made for minimal cycle usage; especially water cooled ones. Also, word on the street is you should create a checklist of things to re-tighten and re-adjust on the X-Carve after most major use sessions. Another reason not to use it for production runs. I can;t say for sure since I don't own one... but if I had to hazard a guess I'd say this is a great guitar if you want to build a few guitars a year and have fun. If you're thinking of having a company and that this machine will be your way towards giant profits and pumping out guitars... I think you need to be in the $5000+ range. Lastly, their free software is very limiting. The first big limit is that it's 2.5D. This means it'll use the x-axis... but just to go up/down to cut the next 2D layer. So don't expect to do belly carve, fretboard radii, arm bevels, etc. unless you spring for a more robust CAM software that covers true 3D. I plan to look into MeshCAM and Universal G-Code sender for Rhino (since that's what I model in). Hope that help, Chris

Keep in mind the shapeoko is a 16"x16" cutting area only... not long enough for most guitar bodies, or any guitar necks. Chris

For the binding repair it's not bad; especially if not doing a refinish, Look up acetone wipe binding installation. Go read it thoroughly, but the general gist is wipe acetone on the binding's inside edges, tape in place, let dry. Do the same for the missing section after you've cut a new matching piece to size and trimmed everything so it's a tight fit. If you're ok with doing a little filler work if your fit isn't perfect you can make a slurry of plastic binding shavings and acetone too.

@Prostheta where is that from then? Chris

Yes, also tell me you made that @Prostheta and that you'll make me one lol. Chris