rwillett

If I was tasteless and loved bling, I could do that, yes.

This is my 3rd music <ahem> related project. I've done a six string which is now professionally setup. The chap in the shop loved it, plugged into a large Marshall stack and proceeded to beat the hell out of the guitar. Big smiles all round and an awful lot of laughs. A few people came in and wanted to try it out. All had fun which is just how it should be. Sadly nobody offered my £5K for it The bass guitar will be based on the lessons learnt from the six string. Current aims are: Use a Fender MIM Jazz bass neck. A kind bass chatter let me have one for virtually nothing. I also got an Aria Pro neck from him as well. Use a similar type of construction to the six string. When I started the six string I used hexagons as the design pattern as I bolted pieces together as I didn't want to glue stuff. That was a mistake as the glue is easier and stronger. Now I will use the Voronoi patterns for the body of the guitar. Very organic, very fluid, quite Gaudi like. I'll try and use pickups that I make myself from the guitar pickup winder I'm making. It will not be headless. I have all the pieces for a headless bass but I am not chopping the head of a decent MIM Fender Jazz. I have an Ibanez neck for that, but thats for later in the year. Worries or things for me to think about Neck dive. The average MIM Jazz body appears to be circa 2.4Kg with no hardware. I have designed a prototype body based around a jazz design but using A Voronoi infill as opposed to hexagons. According to my slicer, if I printed this even at 40% infill which is waaaay too much it only weighs 1.5Kg. Now I need to add in the middle bits, including a plywood backbone so that will add more weight, but I'm going to struggle to get another 1Kg on this to get it balanced and avoid neck dive. I could fill one or two of the pockets with epxoy resin to make it a feature OR I could try and get some really lightweight tuners. Its a big thing to print. I may have to do it in 9 (?) sections as it's nearly 500mm wide and 300mm tall. I need to do the electrics. Less concerned about that, but it needs to be designed in. Not sure if I should use a preamp or not, probably not at the moment. Putting a switch top right on the six string created a lot of routing problems so this time all the electrics will be on the bottom section. I supposed if I concentrates them bottom left, then that will help balance things out. I want to put some body cuts in it to make it easier to play, that will reduce the weight even more Apart from that, its similar to the six string, I need to put brackets for straps, design a pick guard, make it all work, but learnt a lot from the last two I made. Rob

@Frank Blank - Jabba short scales, fretted and fretless, Ibanez SRC6, QSC K12.2, Grace Design preamp. @rwillett - Ibanez short scale, Fender Jazz bass, Fender Mustang bass, Telecaster, Westone six string, 3d printed guitar, small practise bass amp, small practise guitar amp, Mod Dwarf, various guitar/USB interfaces and quite a lot of software and a fair few laptops as required. I live next door Probably cake as well. @ossyrocks- '73 P bass, '73 J bass, '78 P bass, '87 MIJ P Bass, Fender Bassman 50 (rebuilt from the ground up by Gartone), Bergantino Forte D, TE Elf, Barefaced Super Compact and One10, Fender Rumble 100. @sifi2112 Vigier Excess 4, Mas26 (x2) sfx D3 preamp Koch ATR4502 poweramp @neepheid - Some and hopefully all of Epiphone Jack Casady, G&L L-1000, Epiphone Les Paul Standard, G&L Tribute LB-100, Sire D5, Reverend Triad, Yamaha BB1200, Harley Benton HB-50, Soloking MJ-1, Epiphone Explorer, Markbass Mini CMD 121P IV, Markbass NY 121 cab @ead - ACG SLG 32" 4-string; "Lee Sklar bass"; Ibanez Grooveline GS104; Yamaha Attitude Special; SBMM Pete Wentz Stingray sig bass; practice amp (with headphones)

That Voroni generator isn't that easy to use, it puts sketches at a higher level in the component tree and some of the areas just didn't work. However I have managed to get something out, it does look really nice and organic. This might for the basis for a Jazz body with a nice Fender Jazz neck I've got. This bass won't be headless as I can't cut the head off a Fender, well I can but I won't.

@ead don't worry. Il fix it in a new post

Thats sensible. @Frank Blank - Jabba short scales, fretted and fretless, Ibanez SRC6, QSC K12.2, Grace Design preamp. @rwillett - Ibanez short scale, Fender Jazz bass, Fender Mustang bass, Telecaster, Westone six string, 3d printed guitar, small practise bass amp, small practise guitar amp, Mod Dwarf, various guitar/USB interfaces and quite a lot of software and a fair few laptops as required. I live next door Probably cake as well.

Since this is my first one, that sounds like a good idea. I've put the people who have expressed an interest and have said yes on the first post of this thread. Do people normally use the same thread for this or a new thread? Rob

Thanks, sorry about that. Rob

A true star with excellent shaming skills. I approve. There's still a room or two available if you want it. Rob

Can I do a quick roll call and see who is coming, or might be, please? I've held the hall and if there's a sensible number, there's no problem, but for 2-3 people, we could have it in my front room. Thanks Rob

Does that mean you might leave with more than one? That happens to me sometimes, I pop into a shop to have them look at a guitar that needs setup and I somehow end up with two on the way out. As they are both in black gig bags, somebody might not realise it's another one. Rob

Some people vote for Jacob Ress-Mogg as well, no accounting for taste...

Santa has arrived with a late delivery. 2 x 500g of 44AWG and 42(ish) AWG. I suppose this means I need to get my act in to gear and get the stepper motors working properly.

I'd forgotten that about Fry and Adams, they were heavily into IT. As an aside the company I worked for as a sandwich student (do they still exist?), brought something like the 2nd Apple Lisa in the UK when it came out. I worked doing research in formal methods and the dept next door had the Lisa. It was wonderful but I recall that if you dropped the calculator into the wastebin it crashed the OS. Not to be outdone, the dept I worked in brought a few Xero Dolphin workstations and a laser printer. I think they were £25K each at the time and ran Interlisp-D. Thats when I first encountered Lisp and loved it That works out to be around £100K now, so around £400K for three workstations and a printer. Rob

Nice but inaccurate nod to Douglas Adams FTFY

Damm, misremembered that, though technically a panther is just a black leopard. However I will claim that I didn't want to get sued by Douglas Adams estate rather than my memory is failing me I can now say that it saved me two £15 stepper motors, two DRV8825 drivers, a CNC board and an Arduino (though the latter is more difficult as it's more isolated), total of about £30. It's almost paid for itself.

Whilst I've not made a lot of progress over the weekend, beyond what I put above, I have started to understand more about the Vref potentionmeter on the little driver sticks. These drivers slot into the CNC board and controll the stepper motors. You can control the stepper motors directly from an Arduino but its better to control the drivers and let them control the stepper motors as thats what they are designed to do. The Arduino was designed to allow physical components called shields to slot on top of the board. These shields provide additional functionality such as Ethernet, WifI, Real Time Clocks, stepper motor drivers, connections to sensors and so on and so on. I'm using a sheild called a CNC shield, see below which is really just a simple way of adding in stepper motor drivers which are the four chips around the side. CNC Shields are about £2-£3 each and are made in bulk. CNC shields have no programming capability, they just present a simple and uniform way to get stepper motors connected. You access the stepper motors using a standard and uniform coding libraty as well on the Arduino. So instead of making complex calls to pins and timers, all of that complexity is abstracted away. Thats the theory anyway However to get the stepper drivers to work, you have to do some low level coding to enable the stepper motors which appears in documentation that is hidden in a file cabinet in a cellar in the local planning office with the stairs removed, the lightbulb out and a sign saying "Beware of the Panther" on the door. It's only two lines of code, but it's an important two lines of code as nothing works without it. Once thats done, you can connect your PSU up to the blue terminals on the bottoms left. The input is 12V to 36V which is way beyond USB so a dedicated PSU is needed. I used this as an excuse to buy a decent bench power supply This little beauty has one key feature. I can restrict the amount of current that can be drawn. So I set it to 12V and 1A plugged it in and immediately the CNC board and stepper motors started to whine. It turns out that the DRV8826 stepper motor sticks have a little potentionmeter on the top that determines the maximum current draw. I initially set this to 1A so I didn't blow anything up. I didn't understand how this worked so decided to keep increasing the allowed current to see what happened. I got to 12V 4A and still nothing worked. Turns out that the potentionmeter was allowing around 8A per driver to be pulled and if I didn't have a decent bench power supply, I would have fried both driver sticks and the stepper motors. I only really noticed I had a problem when I touched the heat sink and promptly burnt my fingers. So I put a multimeter on the potentionmeter centre point through a screwdriver and a crocodile clip, and the black to ground and turned Vref down to 0.6V from 3V. The whining stopped and the stepper motors started to work. Also the temperature dropped to non burning temperature. The moral of this story is "Dont mess with things that you think you understand but really don't, because it could be expensive and you literaly do get your fingers burnt". Thankfully I didn't blow anything up, and the only damage was my singed fingers. I can see the burnt marks now. Now I have the pots turned down, time to see if my Arduino coding actually will work and drive real stepper motors as opposed to simulators. Rob

Sam I had seen Voronoi stuff before and promptly forgot all about it. Its very organic shaped and almost Gaudi like. Thanks for reminding me about it. The fact there is a F360 generator is great and once I finish the pickup winder, I'll look at using this again. Since I've now been converted to glue for PETG bits, I don't have to worry about flat sections and stuff like that for bolts. I'd love to see your pedalboard with this as well. <hint> The pickup winder is still progressing. Spent most of Sunday evening trying to understand the Vref potentiometer and how it works on a DRV8825. Thanks Rob

So after putting up the bathroom mirror, changing lights, sorting out the clock in my daughters bedroom, taking dog for walk, paying my tax to HMRC, I finally got around to doing some work on the winder. I now have a case for the Arduino, screen and keyboard. I have ordered a mechnical 4x4 keyboard to replace the membrane one but got a 3x4 by mistake so a new one is on it's way. Whilst the membrane keyboard works, it's vile to work with. The gorilla tape just holds it down as I have no idea what the glue would do to it, probably dissolve it. I've attached the lead screw mechanism to the plywood base and am working out how to get the motor that loops the bobbin as square as possible, hence the set square. I would have this all powered up, but the bench power supply came with no cables apart from the mains supply, it needs 4mm banana plugs and do I have any? No! The lead screw mechanism was a little tight as the screws that mount the linear bearing on each arm, were probably out by 0.25mm. Not a lot but thats enough to put friction in the system. So I'm reprinting that with a fraction more leeway in the screw holes to allow it to settle down. This lead screw mechanism is critical and it needs to be as smooth as possible as it moves back and forth as the bobbin rotates. The area at top left is reserved for a dedicated PSU once I work out what the power consumption is. Thanks Rob

There's seven bids on it, so somebody is interested in it.

Odfly enough I did think about that but a simpler model. I have rejected the idea though

It means that I have the basis of the controlling software for a winder. As far as I know, there is no code around for doing this, so I wrote my own, I know that people use electric drills and similar to do windings, but I wanted anything I did to be defined. I'm not very good mechanically so Id rather write software that does things for me, as thats easier for me.I have nothing but admiration for people who can make things creatively. So if I can make this work (note the word if) and they sound OK, it's repeatable. If I want to make a pickup with 10,000 loops of AWG 44 wire or 5,000 loops of AWG 42 wire (thicker than AWG 44), it's a matter of changing the Wire Width parameter and the number of loops. The software should do the rest automatically. If I want to make a thicker bobbin or thinner bobbin, thats just a parameter change. I now have the CNC shield setup, added the stepper drivers, DRV8225, set up 1/8 microstepping, I have a 60V/10A bench power supply but now I just realised I don't have any jumpers to fit the stepper motor wiring to the CNC shield. These are DuPont connectors. I can make them, I even have a kit, but I hate making them, Sod it, Mr Amazon to the rescue. £10 for 6 of them, I only need two (at the moment), so a bargain. Everybody uses their own connectors Rob

Managed to get the IDE working on my Mac. Didn;t have to download any drivers from an obscure Chinese web site. That was never going to happen Copied all the code across to the IDE, compiled it, uploaded it and blow me down with a feather it works. No drivers setup, but I now have working keypad, screen and Mega 2560. That was rather painless. Suspect the CNC shield and stepper motors will be a lot more hassle.

Everything is possible. The easiest way is probably to create a file externally that has all the motor actions, basically the same as a gcode file for 3d printing. The looping motor just loops, an external source with a lot of memory (Raspberry Pi comes to mind), connects to the USB port and sends down the stepper motor commands for the lead screw motor to move it along the X axis, perhaps a step or two extra left or right or take a step out. The most difficult thing would be the connection from Pi to Arduino and keeping the timing right. Other options include making the bobbin with angles so that the top of the bobbin could have a wider diameter to the bottom or the middle is thinner or anything really. As I'm 3d printing the bobbins, that fairly easy. No idea if it makes a difference though. Perhaps this is V3. Rob

Randomisation is not in V1. Scatter winding appears to be how Fender wired these things, basically hand wound trying to make it near but with imperfections. At the moment my focus is getting anything down, neat is a bonus. If the winding pattern can be reduced to a function, then everything is easly possible. What you are describing above is what I would call typewriter winding (just made that up), you wind to the end and then instead of winding back carefully and slowly, you move the wire back quickly to the start and then wind across. There are loads of ways to skin this cat, I could do randomisation and capture this in a stream of data that is sent off the Arduino. I could inject random data into the Arduino from an external source that is precaptured. I have a TrueNas file server here with a lot of free space, so capturing data and storing it is not a problem. There's a number of options to consider but I'm not ready to do that yet. I just want to get something working and try it out. I am going to have to make a test bench guitar for these pickups (6 and 4 string) so might quickly take the 3d printed guitar design and just print the absolute essentials (bridge, pickup and neck modules) and attach it to a plank of wood. Another thing to add to the list Rob