waldemar Posted March 20, 2011 Share Posted March 20, 2011 Hello. I've been toying with the idea of designing a body in a 3D app and having it CNCed for me sometime in the future when circumstances allow. Anyone here done this? If so, how did you approach the neck - ie. ready-made? Designed then built by a luthier to your specs? Of course, shape wise it's all been done before, but just spending a couple of hours pulling around splines in a 3D app really gets you thinking... And wanting..! Here are a couple of the ideas I've had. One conventional, the other not so... Quote Link to comment Share on other sites More sharing options...
Kiwi Posted March 20, 2011 Share Posted March 20, 2011 I've done some research into this. If you have relatively modest expectations, its possible to whack something together in Google Sketch Up and export it to a 3 axis machine. If you feel like doing something with compound curves (warwick/spector bodies), things get a lot more complicated and require a 5 axis machine. If you need small hardware jobs done, its also worth looking at this: [url="http://www.emachineshop.com/"]http://www.emachineshop.com/[/url] Materials tolerances are hard to judge by computer, neck pocket fits still need to be done by hand...unless you have the neck dimensions measured to fractions of a millimetre or dont have high expectations about the fit. Quote Link to comment Share on other sites More sharing options...
waldemar Posted March 20, 2011 Author Share Posted March 20, 2011 [quote name='Crazykiwi' post='1169149' date='Mar 20 2011, 07:42 AM']neck pocket fits still need to be done by hand...unless you have the neck dimensions measured to fractions of a millimetre or dont have high expectations about the fit.[/quote] Nah, I'm looking for a Fender style fit... Hehe. What I imagine will happen is that I'll make the pocket ever-so-slightly under-size and then hand tool it to accept whatever neck I decide to use - perhaps a standard size Warmoth with a paddle headstock that I can rout down... I hear you on the complexities of the model - a while back I spoke to a guy based up here in the north who offers the service: [url="http://www.woodrouting.co.uk/"]http://www.woodrouting.co.uk/[/url] Looks like he can get some pretty good results, but for my own sake I'll probably keep it fairly simple to begin with - come to think of it, I quite fancy a Warwick shape in a slab-style body. It's all a bit pie in the sky at the moment due to moving house and work commitments, but would love to have a go at this sometime! I'll stick to virtual ones for now. Cheers. Quote Link to comment Share on other sites More sharing options...
Kiwi Posted March 22, 2011 Share Posted March 22, 2011 Wow, super handy link! Thanks! Gibson have got things down to a fine art where they'll do a body by hand and scan it into their milling machines and it turns out pretty much perfect. That would be my preferred route as well but a 3d scanner is a fairly expensive and specialised piece of kit and prices for scanning services were pretty steep last time I looked. Industrial design schools will have one though so it may be possible to wangle something if you have contacts. Quote Link to comment Share on other sites More sharing options...
apa Posted March 22, 2011 Share Posted March 22, 2011 I got as far as pressing the button on a 3D modelled body for a Ray project. Only thing stopping me was the guy who was programming the Tooling path. (I would have done it if they would let me on thier software for a couple of hours!!) It all depends on the quality of the kit your using both Software and hardwear. If you take your time you could get some decent results from spline curves then finish the curvature by hand. (Although if you want the ultimate you should use NURBS ) Try and find a tool makers or fabricators around your area and like crazy kiwi says, the local uni / colleges may be interested. I do think you could machine out anything with a 3 1/2 axis machine as long as there arent any undercuts. The biggest problem is the practicalities of clamping and setting up the machining. My solution was to machine one half out like a jigsaw piece with spru sections left in to hold the body in the stock material then turn it over and machine the other side out with pegs for reference positions. Like I say it never happened but was the plan. Bare in mind that all that would involve quite a bit of expencive machinists and programmers time unless they wouldnt mind you wandering around thier machine shop playing with thier expencive and sharp tools!! Hope this helps A Quote Link to comment Share on other sites More sharing options...
Kiwi Posted March 22, 2011 Share Posted March 22, 2011 [quote name='apa' post='1171672' date='Mar 22 2011, 07:48 AM']I got as far as pressing the button on a 3D modelled body for a Ray project. Only thing stopping me was the guy who was programming the Tooling path.[/quote] The free software offered by emachine works out the tooling path for you. Quote Link to comment Share on other sites More sharing options...
Count Bassy Posted March 22, 2011 Share Posted March 22, 2011 [quote name='waldemar' post='1169131' date='Mar 20 2011, 04:57 AM']Hello. I've been toying with the idea of designing a body in a 3D app and having it CNCed for me sometime in the future when circumstances allow. Anyone here done this? If so, how did you approach the neck - ie. ready-made? Designed then built by a luthier to your specs? Of course, shape wise it's all been done before, but just spending a couple of hours pulling around splines in a 3D app really gets you thinking... And wanting..! Here are a couple of the ideas I've had. One conventional, the other not so... [/quote] I don't see anything there that couldn't be done with a three axis machine and a ball end cutter, provided you had the right post processor to go from the CAD model to the NC data. You'd still want to hand sand to take out the machining marks however. Why not design your neck in the same way and get that routed out at the same time? Personally I don't see a problem with the neck/pocket tolerance, what sort of tolerance are you looking for ? Quote Link to comment Share on other sites More sharing options...
waldemar Posted March 23, 2011 Author Share Posted March 23, 2011 Thank you all for your posts. Count: The neck's just a bit too daunting for me, really - being the business end of the project and arguably the bit that [i][u]really[/u][/i] does need to be right (playability wise) I'd sooner buy something that's 'reasonably easy' to modify off the shelf - that's not to say that I wouldn't make my own at some point, just not now, I'm far too green... Apa - yeah, the models illustrated in the OP are based on NURBS - or rather Cinema4D hyper-nurbs, which some might argue aren't [i]real[/i] NURBS but for my purposes (so far) work in a near as dammit fashion. I do have a friend who has limited access to a machine that he'll let me put some high density polystyrene through, so I dare say I'll learn a bit from that before offering up a final model to someone with the experience to do the job properly. All interesting stuff, and should it go slightly awry, I don't mind cracking out the sandpaper... Cheers! Quote Link to comment Share on other sites More sharing options...
Kiwi Posted March 23, 2011 Share Posted March 23, 2011 [quote name='Count Bassy' post='1171752' date='Mar 22 2011, 08:54 AM']I don't see anything there that couldn't be done with a three axis machine and a ball end cutter, provided you had the right post processor to go from the CAD model to the NC data. You'd still want to hand sand to take out the machining marks however.[/quote] Its definitely possible but how to register the body for machining the underside once the top is done? Spector tend to leave a chunk of the neck unmachined at the bridge end of the bass and deal with it by hand during general sanding. The risk of getting it wrong even by a few mm is quite high. Quote Link to comment Share on other sites More sharing options...
Count Bassy Posted March 23, 2011 Share Posted March 23, 2011 (edited) [quote name='Crazykiwi' post='1172856' date='Mar 23 2011, 03:36 AM']Its definitely possible but how to register the body for machining the underside once the top is done? Spector tend to leave a chunk of the neck unmachined at the bridge end of the bass and deal with it by hand during general sanding. The risk of getting it wrong even by a few mm is quite high.[/quote] Yes, that's what I would tend to do as well leave a couple of 'tabs' on it some where with a through hole in each and use those holes to do the alignment for the second side. When you're sure you've finished machining on each side then your final program could machine the tabs themselves off. Also - do some practice runs on cheap material first - either foam as has been suggested, or even a chunk of pine/mdf, which would allow you to make a complete mock up of the finished thing, bolting the neck on etc, before you commit to the expensive bit of wood. Also, Waldemar, using cheap materials you could make mock ups of your own neck design and try out different profiles etc. Personally, If I had access to an NC machine I would use if for almost everything, including machining the fret board radius (even putting the slots in if it was the right cutter) The beauty of using a machine is that if six months later you wanted, say, a fretless version you simple run the programs again and you'll get the same part out! Edited March 23, 2011 by Count Bassy Quote Link to comment Share on other sites More sharing options...
apa Posted March 23, 2011 Share Posted March 23, 2011 [quote name='waldemar' post='1172845' date='Mar 23 2011, 01:44 AM']Thank you all for your posts. Count: The neck's just a bit too daunting for me, really - being the business end of the project and arguably the bit that [i][u]really[/u][/i] does need to be right (playability wise) I'd sooner buy something that's 'reasonably easy' to modify off the shelf - that's not to say that I wouldn't make my own at some point, just not now, I'm far too green... Apa - yeah, the models illustrated in the OP are based on NURBS - or rather Cinema4D hyper-nurbs, which some might argue aren't [i]real[/i] NURBS but for my purposes (so far) work in a near as dammit fashion. I do have a friend who has limited access to a machine that he'll let me put some high density polystyrene through, so I dare say I'll learn a bit from that before offering up a final model to someone with the experience to do the job properly. All interesting stuff, and should it go slightly awry, I don't mind cracking out the sandpaper... Cheers![/quote] Yep if you want a real tangent/curvature flow you need NURBS I think your there with your mate and his machine. As long as you have the right post processor your good to go. May I suggest you try a couple of test peices at 1/4 scale to save on materials and time using the styrene. The way to match the halfs when you flip them over is the make damn sure your stock (The lump your machining out of) is 110% square. Then position a reference edge on 2 sides to the bed. You can use the CNC and a 'wobble bar' to get all this right. Then machine from the centre. Im assuming your friend knows how to use the machine so he will know what I mean. Remember preperation is 9/10th of the work and measure twice, cut once. Have fun and look forward to the outcome A Quote Link to comment Share on other sites More sharing options...
Count Bassy Posted March 23, 2011 Share Posted March 23, 2011 If you're going to use NURBS then check that your mate's machine will process the NURBS data, some controls will, some controls won't (or have it as an option). If not then best get the post processor to output it as masses of straight lines, though this can cause problems with the file size (again depending on the control). Quote Link to comment Share on other sites More sharing options...
apa Posted March 24, 2011 Share Posted March 24, 2011 Or convert it to an IGES or Polygon. They are usually safe bets. This is all getting rather geeky lol A Quote Link to comment Share on other sites More sharing options...
Count Bassy Posted March 24, 2011 Share Posted March 24, 2011 [quote name='apa' post='1174279' date='Mar 24 2011, 09:40 AM']Or convert it to an IGES or Polygon. They are usually safe bets. This is all getting rather geeky lol A[/quote] Geeks of the world unite! Quote Link to comment Share on other sites More sharing options...
waldemar Posted February 8, 2014 Author Share Posted February 8, 2014 Apologies for a. resurrecting such an old thread and b. steering it a bit OT... Well, the CNC bass project hasn't as yet come to fruition. Why? Because I've been busy making the CNC vertical mill which in turn will help me make the CNC router which will make the bass, by which point I'd have been able to buy several of my dream basses, but where's the fun in that..? A couple of pics attached and a vid of a test cut here: [media]http://www.youtube.com/watch?v=VR9hAaXSzto[/media] Might even get into a spot of engraving... Stay tuned for another update in, I dunno 3 more years...? Wal. Quote Link to comment Share on other sites More sharing options...
Diablo Posted February 8, 2014 Share Posted February 8, 2014 Even a 2 1/2 axis machine will do this if you don't mind a bit of hand finishing. For machining the A and B sides you simply machine 3x Z, 2x X and 1xY datums onto the part when doing the A, and use those as datums for setting the B side on the machine. Common practice when machining castings which I do enough of on my own CNC mill. When all machining is done you just machine or cut off and hand finish the datum plane locators to get rid of them. The most important thing is machine stability, mass = good, and thermal stability is important. Stiffness and spindle speed help and also time, the smaller the stepover the less hand finishing you need! Cheers, Rich Quote Link to comment Share on other sites More sharing options...
waldemar Posted February 9, 2014 Author Share Posted February 9, 2014 Hi Rich, I'm not familiar with the "3x Z, 2x X and 1xY datum" technique (I've no engineering background and I undertook this CNC build as a hobbyist) perhaps drop me a PM with a bit more info if you have the time and inclination. Would be nice to learn something new. Cheers. Wal. Quote Link to comment Share on other sites More sharing options...
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