ESP M-II type "Invaders" Superstrat

[Prostheta]

Just under a day of curing and the epoxy has become "fingerprint touch" hard. This will need a few days to fully cure, which is fine.

I was wondering how to mask off the logos during paint, and I hadn't come up with a good idea until last night. I considered whether a vinyl outline could be cut, but that's expensive and unlikely to work with the detail requirement. The best I had come up with was good ol' hand cutting. It then hit me that I could use the CNC with an engraving bit to cut through tape. Duh! Immediately obvious, and always what happens when looking for distant solutions instead of what's in front of you.

I'll have to test this since getting a clean edge is important. I don't want whatever backing material (Corian? Plywood?) I use to dirty up the edges, so it might be a very fine balance of cutting depth to *just* make it through the tape. I've sort of done this before though, making a mitred solid wood "net" backed up with tape that folds up neatly into a cube (Lament Configuration FWIW so I know that the precision is possible. I recall that 3M blue tape is 0,14mm thick, and I can get precise depths to hundredths of a mm when I calibrate endmills. This should be possible. If I can cut through 0,1mm (or that sort of thing) then the remaining fraction should part itself when pulling up the mask with tweezers.

[Prostheta]

The epoxy scrapes back nicely, but is very rough on the hook. Once I managed to get it near level, I block sanded flat to 320 grit....

Aside from a couple of very minor faults, this is absolutely what I was aiming for. Under the decal the logo will have a little depth and will be visible. When illuminated it's BRIGHT. Silly silly bright. So bright that it caused the camera to dial back the exposure in the second photo in a dim room!

[Prostheta]

I CNCed a nice Sapele body blank today. The neck pocket was cut first by roughing with a 20mm carbide knife endmill, finishing with a 10mm three-flute upshear. The perimeter roughed in at 1mm from final size with a 16mm three-flute upshear endmill, then finishing with a single pass. The corners around the neck pocket needed a little cleaning with a chisel and sandpaper.

This won't be the actual body I'll use on this Mirage, as it's screaming for a transparent finish. It isn't special by a long shot, and the matching isn't spectacular either. The other two blanks I have will get the same CNC treatment. One is similar to this one (same board) whilst the other is plain straight grain, pretty much paint grade. That's the one I'll be using here.

I have two auxiliary workholding beds to cut into some MDF. One for working on the face and another for the rear. I imagine that I will drive some threaded inserts into these so that I can add simple bolted holddown clamps for the various operations. Most importantly, it makes operations repeatable for future Mirage builds, especially the carved top version.

[Muzz]

That body would look fantastic natural and clear or stained red and covered in red candy transparent finish.

[mistermikev]

On 9/26/2021 at 1:57 AM, Prostheta said:

 

This solution is similar, and I like the enclosed nature of the mechanism even though it is more complex and requires additional material such as the Plexi.

 

I don't currently own a router appropriate for that length of bit, however I can certainly borrow one until I do. The profile pucks seem a perfect solution since I am very much a desktop designer, CNC operator and propellorhead, plus it's a good jig to have going forward.

this is one of my fav videos.  the sheltima jig... before I got cnc I had seriously considered building on of these.  not so much for being able to mass produce but more to be able to consistently build a neck and know that it was "the shape I liked".  that said... I can't help but wonder why you didn't cnc the neck?

 

the glow in the dark logo is gonna look killer.  vcool.

[Prostheta]

4 hours ago, Muzz said:

That body would look fantastic natural and clear or stained red and covered in red candy transparent finish.

I have a shelved project which was a cross between an Ibby RG and a Gibson SG. The whole antique cherry red thing over Mahogany/Sapele, pickguard, etc. This one needs fixing. You're right though. It's a nice potential look. Unfortunately unless I can get candies in a can, I don't really have the experience on the equipment to shoot that. I have the spray guns, dry compressed air and a booth available, I just need to find some good time to take those skills on before I commit to a real workpiece.

[Prostheta]

3 hours ago, mistermikev said:

this is one of my fav videos.  the sheltima jig... before I got cnc I had seriously considered building on of these.  not so much for being able to mass produce but more to be able to consistently build a neck and know that it was "the shape I liked".  that said... I can't help but wonder why you didn't cnc the neck?

 

the glow in the dark logo is gonna look killer.  vcool.

Thanks man! Well, I could CNC the neck profile, but it's all about workholding. The neck won't have a flat bearing surface once the fingerboard is on, and if it shifts during the cycle then the whole thing gets screwed up. I could do the profile before I glue the fingerboard on, however there's potential for splintering along the very edge. I also prefer clamping flat to flat to get even pressure, so having an existing neck profile makes glueup more tedious and introduces potential for error. Doing the profile by hand using a jig is controllable and very hands-on. The adjustment built into the jig along with the easy puck-based profile transitioning makes it quicker to dial in than an entire CNC program.

Plus I love jigs. @ScottR knows this!

[Prostheta]

I got chance to buy some more DNA today, so here's the nicer body wetted out.

 

I've landed myself with three Sapele bodies.

 

I also cut two MDF workholding boards, one mirrored in the Y axis along the centreline.

[mistermikev]

57 minutes ago, Prostheta said:

Thanks man! Well, I could CNC the neck profile, but it's all about workholding. The neck won't have a flat bearing surface once the fingerboard is on, and if it shifts during the cycle then the whole thing gets screwed up. I could do the profile before I glue the fingerboard on, however there's potential for splintering along the very edge. I also prefer clamping flat to flat to get even pressure, so having an existing neck profile makes glueup more tedious and introduces potential for error. Doing the profile by hand using a jig is controllable and very hands-on. The adjustment built into the jig along with the easy puck-based profile transitioning makes it quicker to dial in than an entire CNC program.

Plus I love jigs. @ScottR knows this!

all solid reasoning.  thanks for solving the mystery!!

[Prostheta]

I was contemplating the whole puck approach and realised that you could easily mix and match them. Essentially creating hybrid profiles. Using a standardish C profile for the head end and some asymmetrical profile for the body end would result in a "low percent asymmetrical, mostly C" 1st fret profile and a "mostly asymmetrical, low percent C" 12th fret. That would be very cool to try out at some point, however I don't think I'd do so without adding in some additional reinforcement to prevent twisting....

[mistermikev]

2 hours ago, Prostheta said:

I was contemplating the whole puck approach and realised that you could easily mix and match them. Essentially creating hybrid profiles. Using a standardish C profile for the head end and some asymmetrical profile for the body end would result in a "low percent asymmetrical, mostly C" 1st fret profile and a "mostly asymmetrical, low percent C" 12th fret. That would be very cool to try out at some point, however I don't think I'd do so without adding in some additional reinforcement to prevent twisting....

right on.  well if strandberg gets away with that shape... I'm thinking almost nothing would be problematic lol!

[Prostheta]

Asymmetrical necks are a pretty old concept. Rick Toone did/does some radical sort of profile that accentuates the asymmetry by using a trapezoidal shape. Whether that was a decision based on making it a visible feature over functionality (ideas are often played out in words differently to their true intent) isn't known, but still. I'm not considering an asymmetrical profile for this project just on the basis that I could do them with this jig, but it does open out a lot more flexibility going forward. I'm wondering whether I should be a little more forward thinking in this regard and make the jig so that I can also do bass necks, but that sort of thinking is what ends up paralysing me. Anyway.

Talking of internally-sidetracking myself so far that I forget "why I went into that room in the house in the first place", I'm just about to head out of the door to investigate local auto paint shops. Specifically I want to locate somewhere local that will mix aerosol 2K to codes. The two colours I have in mind for a white pearl version of this Mirage are a Subaru Pearl White (I need to look at the chips to remind myself which one this is...champagne-y) and Porsche Pearl White (DuPont code AST1265D). I need the base plus cans of true 2K with the separate hardener canister since pre-mixed 2K is not really as durable or hard when cured.

Porsche Pearl White:

 

For reference, I meant this rendering idea I threw together a few weeks back....

 

....which in turn was inspired by this....

[mistermikev]

5 hours ago, Prostheta said:

Asymmetrical necks are a pretty old concept. Rick Toone did/does some radical sort of profile that accentuates the asymmetry by using a trapezoidal shape. Whether that was a decision based on making it a visible feature over functionality (ideas are often played out in words differently to their true intent) isn't known, but still. I'm not considering an asymmetrical profile for this project just on the basis that I could do them with this jig, but it does open out a lot more flexibility going forward. I'm wondering whether I should be a little more forward thinking in this regard and make the jig so that I can also do bass necks, but that sort of thinking is what ends up paralysing me. Anyway.

Talking of internally-sidetracking myself so far that I forget "why I went into that room in the house in the first place", I'm just about to head out of the door to investigate local auto paint shops. Specifically I want to locate somewhere local that will mix aerosol 2K to codes. The two colours I have in mind for a white pearl version of this Mirage are a Subaru Pearl White (I need to look at the chips to remind myself which one this is...champagne-y) and Porsche Pearl White (DuPont code AST1265D). I need the base plus cans of true 2K with the separate hardener canister since pre-mixed 2K is not really as durable or hard when cured.

Porsche Pearl White:

 

For reference, I meant this rendering idea I threw together a few weeks back....

 

....which in turn was inspired by this....

idk if I'd like this profile at all... but the sm concept using an mm axis profile flipped on either end might be really noice:

ps that porsche is a lovely color!!

 

 

[Prostheta]

It's actually an Aston Martin, but they used a Porsche colour! I had a conversation with one of the guys at ProVäri and he's pretty familiar with the ground I think. Unfortunately, that's mostly industrial paint rather than auto specific, but he was certainly more friendly than the guy at Colornet. The Invaders guitar needs a good jet black and a proper 2k clear over the top. I'm unsure how high end the stuff ProVäri gets in terms of the deep glassy blacks, but I will get an honest answer there at the very least.

The basis I think I'll be working with for the paint is to either hand apply an epoxy sealing layer or an aerosol epoxy primer. This will be sanded back to within an inch of its life. Over that I'll be using a simple black primer as a guide coat so that I can block sand and tune the surfaces towards perfection. The ultimate choice of black paint matters little if the substrate isn't James Webb telescope mirror grade. The black primer will then be laid heavier and block sanded before moving onto the black of choice. There's endless debate over what is the "best" black, and in general you learn nothing unless you're doing the practical work to reinforce ideas, see how they work for you. It's easy to end up with an Internet list of stuff that is of no use or just isn't available. I'm working with aerosols until I can put in some hours behind the gun, which won't be now. The bottom line is that perfect prep with a reasonable black and clear coat will piss on poor prep and the most boutique-y top dollar product. I can't imagine that I will get anything as glassy as that Ibanez I posted a while back, however with patient prep work I can dial in some good glossiness and hopefully some depth. The trick will be keeping the binding clean and level. I can't go too thick on the basecoat since that will create a ledge at the binding transition, and that will require some major wasteful burying in clear. Building up paint/clear on edges for any reason is a bad place to be. I also don't want to pile on too many layers of clear as too much will "collapse" and look like shit. Using Spray Max 2K clear restricts me to a limited amount of product plus a small time window with which to use it. That might push me to do it right rather than push too much product.

Any thoughts would be welcomed, but do bear in mind the constraints I have.

[Prostheta]

Body program on the CNC coming together. Rear tremolo cavities and electronics, drilled for press-fit inserts.

 

Fingerboard milled on the CNC. Inlays were slightly enlarged and cut slightly shallower. No problems with the eyes this time! I spent ten minutes with a pin and needle file inspecting each pocket and perimeter using magnifier goggles. Safe!

 

Inlays wetted with plain casting epoxy, heated plus the fingerboard was warmed also. Again, a lot of time with a pin and magnifiers checking for bubbles and filling/popping.

 

 

I took off a small quantity of the epoxy....

 

....then filled it with glow pigment until it became "chalky", then added a little epoxy until it wetted through with heat. Maximum pigment content.

 

 

Drop filled over the inlays. The pigment crashes through with a bit of heat and displaces the lower density straight epoxy through gravity.

 

A second drop fill and liberal amounts of heating to lower viscosity and encourage sedimentation crashing.

 

Whoa, brighter than the first test set! Now it's a waiting game for the epoxy to chooch.

[asgeirogm]

Looking great, I can't wait see the inlays cleaned up

[Prostheta]

I might be able to surface the board Tuesday or Wednesday if the epoxy is sufficiently cured. I'm concerned that 15th, 17th and 21st didn't work well enough and may need recutting and filling. 

[mistermikev]

17 hours ago, Prostheta said:

Body program on the CNC coming together. Rear tremolo cavities and electronics, drilled for press-fit inserts.

 

Fingerboard milled on the CNC. Inlays were slightly enlarged and cut slightly shallower. No problems with the eyes this time! I spent ten minutes with a pin and needle file inspecting each pocket and perimeter using magnifier goggles. Safe!

 

Inlays wetted with plain casting epoxy, heated plus the fingerboard was warmed also. Again, a lot of time with a pin and magnifiers checking for bubbles and filling/popping.

 

 

I took off a small quantity of the epoxy....

 

....then filled it with glow pigment until it became "chalky", then added a little epoxy until it wetted through with heat. Maximum pigment content.

 

 

Drop filled over the inlays. The pigment crashes through with a bit of heat and displaces the lower density straight epoxy through gravity.

 

A second drop fill and liberal amounts of heating to lower viscosity and encourage sedimentation crashing.

 

Whoa, brighter than the first test set! Now it's a waiting game for the epoxy to chooch.

that fretboard looks awesome.  the gobs of green goo look like quatrophonic lung butter tho.  hoik.... patewey.

[Muzz]

16 hours ago, Prostheta said:

I might be able to surface the board Tuesday or Wednesday if the epoxy is sufficiently cured. I'm concerned that 15th, 17th and 21st didn't work well enough and may need recutting and filling. 

The space invaders look terrific, looking forward to seeing those sanded down. If you are concerned about those fret slots then they do need filling and recutting. So easy to do and you are not going to be happy about it until you do it. 

[Prostheta]

It's not the fret slots I was concerned about, it was the inlays at those positions. The fret slots are sized well with the 0,5mm cutter. The potential issue was that the finest details might increase the localised (forgive me if my terminology is incorrect) shear within the epoxy, not allowing pigment to crash through as well as the larger, more open inlays. It turns out this was not the case. I left the board heating today and resurfaced it on the CNC.

I still don't think that these are perfect, however I think that this is as good as one can expect from wood and casting-in-place which was the whole idea from the beginning. Unfortunately the main point of the technique - the binding - was shown to be too difficult to realise as discussed.

I'll try and get a photo of the board fully illuminated. The epoxy is hard enough to be cut, but not sanded. Once it's fully cured (a week is a reasonable rule of thumb with slow casting epoxies) I can sand the board with a radius beam. I should get it bound and glued to the neck next I guess.

[Prostheta]

Bound and cleaned up a bit. By the weekend it should be possible to sand and polish through the grades.

[ScottR]

Cool.

SR

[Muzz]

Everything's looking good there.

[Prostheta]

Freshly bound. Hopefully the inlays pop a bit better once I can get sanding the board and cleaning it up with alcohol. At this stage I think it'll burn the surface.

[Muzz]

I can almost hear the lasers and the shuffling space invaders