CAD/CAM Tips Thread...

Gizmo

So while i had my Workbee desktop CNC clone up for sale here in misc (it's now getting a plate/ballscrew upgrade) i got a few questions about how i made/cut the body curves on this "Maverick" inspired Super Tele i posted pics of & that im currently building

To save just replying to one or 2 users i thought it better to throw this up in a M&M CAD/CAM thread, as there are 1000 & 1 ways to do this i'll just say mine isn't the be all and end all (but it works for me) & should work in any 3d modeling software (commands might not be nammed the same but if it's current it should have these type of features)

If anyone has other methods/tips/trick for this or anyother kind of CAD/CAM stuff feel free to chip in and info etc etc, im sure video of this would make a lot more sense but  hey a pic is worth a 1000 words right

1. Get you 2d body outline curves sorted and a solid extrusion pulled to cut/split.

2. Using a control point curve/line draw between where you want your cut to start/end adding a handful of point's along the way, lock this line in planar so i stays flush with the top of your body (in the next pic this can be seen in the upper left window) then alter each control point to create the type of curve/flow you want cut too (add more control point's if you need but the fewer the better)

3. Creat a control point cuvre that scoops down in Z and extends out in Y (above pic lower right window) you can make this sharper if you want that type of look/feel, copy paste this curve and move it so there is one at the start/end of the flow/curve

4.Join the bottom of the scoop curve with a line

5.Select each of the curves you made above and perform a "networksurface" command

6. Select the main body & use the "Split" command, select the network surface you just created to as the cutting object.

 

7. rerun the split command but this time select the network surface as the object to be cut and use the section of the body you just split out as the cutting object

8. delete/hide the networksurface/curves/split section & join/union the slipt surfaces back to the main body, you now have a nice flowing bevel alone the edge of your body.

When this is Milled i use a rough pass with a 6mm downcut bit to hog out steps and then run a parallel finishing pass with either a 6mm,4mm or 2mm ball nose bit with a 5% step over (yep that take's longer but doesn't need sanding at all)...one other tip is that i run a full outline cut to about 12mm deep as part of the rough cut (see the top photo) that stop's the ball end bit from ploughing into a wall of wood when it's cutting around the edges of the body.

you can use the above curve/networksurface/split method to make belly cut's,horn access cuts and heel scoops etc etc, as i say 1000 & 1 ways to do this type of stuff but this works for me and mill's very nicley. 

Pretty sure that's clear as mud, but might be of use to someone

Laters

Steve

WezV

Thanks for this.    I do keep thinking i may need a CNC at some point, and now I've started to get to grips with 2D for the laser work it seems like the next logical step

TTony

WezV said:

 I do keep thinking i may need a CNC

“need”.

They are incredibly useful things, for all sorts of tasks.  I think the key is being able to draw/model the thing you want to cut.  It becomes more about the software than the woodwork.

Gizmo

WezV said:

Thanks for this.    I do keep thinking i may need a CNC at some point, and now I've started to get to grips with 2D for the laser work it seems like the next logical step

TTony said:

“need”.

They are incredibly useful things, for all sorts of tasks.  I think the key is being able to draw/model the thing you want to cut.  It becomes more about the software than the woodwork.

Well i built stuff by hand and with templates for a fair few years before deciding to do a self build of the openbuilds workbee desktop CNC (one it's had a plate/screw upgrade im using it to build my own CNC design), It's really like having another person in the workshop, set it up hit go and just keep an eye on it while i get on with other things.

The main reason i went CNC is because it helped stop the error creep, in the past id design in PS-Print in sections-tape together-cut out-transfer to MDF -Cut out-sand- use template to cut out, now i just design in CAD and cut out...simples

@TTony yes you are right the bulk of the time is shifted to the CAD/CAM, & it does take a bit of time to get your workflow down, but the great things is once you have your design's such as pup/vol,tone/floyd cavities nailed down you can just C&V them between designs.

Some Video's that helped me wrap my head around things in starting out in CNC where by a guy from Helix guitars on YT (pity he doesn't post anymore it seems) he's build a neck/volute video is pure gold.

Hopping others will add to this thread but if anyone thinks i can help with this stuff just shout,im not saying in the alpha/omega of CNC CAD/CAM but i like to think i have some clue

Laters

TTony

Cheers @Gizmo ;

Here's another YT on creating a neck.  I should really give this a go (I'd completely forgotten about it and lost it amongst all the other bookmarked YT videos!).


And another

Sporky

I think that's Rhino3D in the first post? Grasshopper is a fantastic tool for that - I had a setup (need to find it or recreate it) that made fretboards based on scale length, number of frets, width at each end, and radius at each end. Really handy for doing odd things.

Gizmo

Sporky said:

I think that's Rhino3D in the first post? Grasshopper is a fantastic tool for that - I had a setup (need to find it or recreate it) that made fretboards based on scale length, number of frets, width at each end, and radius at each end. Really handy for doing odd things.

Good eye, yep that's rhino it's way way to highend for just making guitars but i scored a laptop mid lockdown from a design house that had shut down and thrown there stuff into clearance , i thought it might be a bit doggy but it validates online so im not one to look a gifthorse and all that.

I'll give greasshopper a look thx, till now i've been using fretfind2d to get dxf's for fretboards

A lot of guys over at sevenstring.org tend to use fusion360 of there CAD/CAM stuff (still free for non-commercial use) ,but i really dislike it's 3d camera controls, Rhino feel's more like the old Quake & unreal lvl ed's i used to use to make gaming mods with.

WezV

How difficult was it to build the workbee clone?   are there any guides for this anywhere?

If you do make another, a build thread would be great!

jasonbone75

I'm geeking out on the pockets for neodymium magnets on the covers :-) I can potentially contribute to this thread from a Solidworks perspective which is where all my design and modelling work takes place (mostly unrelated to guitar for work but I have dabbled and can advise on how to do things in SW). 

Sporky

Gizmo said:

I'll give greasshopper a look thx, till now i've been using fretfind2d to get dxf's for fretboards

It's basically a parametric plug-in. You can make it do all sorts of things - bit of a learning curve, but it's almost limitless. I had it draw up and create a cutlist for a chest of drawers, only you could say how many rows of drawers, how many in each row, what thickness timber, all sorts of things. I seem to have lost a load of them at some point, but the fretboard calculator was well worth building.

What CAM agent are you using? I'm on MADCAM.

Gizmo

WezV said:

How difficult was it to build the workbee clone?   are there any guides for this anywhere?

If you do make another, a build thread would be great!

The worst part was the shopping list! OpenBuilds do a full kit for the Workbee and at the time i built it there's was about £1200,(almost £1500 now i think!) that was with no router/drivers/psu/stepper motors.....just the bare mech kit.

I did some shopping about on Ali and ebay and built the whole thing for about £800 that inc'ed a router/driver/controller/psu/motors

If your thinking of building a DIY Desktop CNC clone right now id skip the workbee basic and look at cloning the Bulkman Ultimate Bee, that's a ballscrew rail update of the workbee with some other tweaks (look on YT for some builds in op videos),infact you can get the full frame kit in a package for the Ultimate Bee off aliexpress for about £700 (1000x750mm) or get the bulkman plates and shop around for the other parts yourself and build it for about £600 (or less if you catch some of Ali's mega sales) If you can wire pups (which i know you can!) the PSU/steppers motors and Controller shouldn't cause you any issue in setting up/config

There are build guides all over YT and the Openbuilds pages have all the info you need, looking at it to start with it's a bit daunting for sure but take it section by section and you'd have it up a running in a few days no doubt. 

a bit more on why i wouldn't go wit the basic workbee....The weakest part of the workbee is the V wheel rail/support, they are a total pain in the ass to balance and adjust (they tighten on a small cam) and on the dual X axis if you don't get them perfectly balanced the ganrty can lagg on one side cause the job to miss stepps and really mess you workpiece up!

Onto my own rebuild....I did look at getting my own custom plates cut by someone else but pretty much all the quotes were coming back in the £300+ range, & as I wouldn't trust my V wheel WB to cut so much aliuminum,I've just decided to grab the BM UB plates and all the ballscrew rails etc i need for the upgrade & once there installed i'll then cut my own replacements plates and sell just the BM plates on.that way i get my own plates done by my own hand for less that £100 win/win

My own take on the Rail/BS design will also have a fixed Z plate, that way the the motor doesn't have to lift it's own weight, and is closer to the rail so has less twist....last revision of it looks something like this in CAD.....

Sporky said:

What CAM agent are you using? I'm on MADCAM.

RhinoCAM which also came on the laptop i got from the clearance, i didn't use it for a long time because it was a bit scary and most all cuts/jons i started with were just 2d inside/outside cuts,im into using it now though and the mechsoft vid's on YT helped me a lot.....like Rhino i will never use even 1/3 of it's features.....it keeps telling me there's updates/new features i can download but if Ive leant anything on close to 30 years from working in I.T.....it's don't update if it's working without any issues

Dam that's a big a wall of txt...Soz guys

 

WezV

Nah, that is very helpful stuff.  Thanks!

Sporky

I can vouch that building the controls us entirely doable. My K2's control box caught fire - incredibly shoddily built. I made a new one from all new bits (except the mains transformer, rectifier, and caps). I'll dig out the photos if anyone's interested. 

Gizmo

I think the 2 fav things i've done so far with the CNC that i would have had a lot of trouble doing by hand are

Brass Headless string retainer, brass cost £3 tap kit £1.50 Bolts £1

LED side markers,I got a few packs of these 5mm flat led's from ali, they are clear off and super bright blue on & look great either way

M1ck

I know there are all sorts of flavors for 3D CADCAM software and some will have their preferences over all others (I know I do!), but I just thought I’d throw this into the ring.
Autodesk are really pushing Fusion 360 as ‘the way forward’ and they have a ‘free for hobbyist/small business’ version (I’ll try to find the link for those that are interested) it’s been a little while since I used it but I’m pretty sure it has a dxf that can be exported to a CNC. I found it very intuitive, it’s very similar to Autodesk Inventor and it works in the cloud (so you need an Internet connection to validate the license when you use it) the plus side of this is you are always using the latest version. 

Even if you don’t use it for CNC work it does a great job of 3D models for those interested more in design. I did a whole suite of offices with it a couple of years ago with full colour renders right down to individual parts and finishes - I can only assume it’s got better since then! It also works with 3d controllers such as the 3D-Connexion space mouse

Gizmo

So i finally got the Workbee rebuilt with Ballscrews and rails....

Took way longer than i expected, mainly because i needed to import pretty much all the parts, the translation barrier threw up a gew hitches along the way, one example of this is that i asked for 1000mm ballscrew lenght + the screws mounting/attachment (20mm one side & 40mm the other) so they should have been made & come @ 1060mm but they send 1000mm overall lengh screws meaning i lost 60mm and then had to cut all the frame lenghts down......Still £450 on the upgade vs £1600 for a new full kit,i can live with 60mm loss....

I've only run a few tests cut's sofar but it's much much faster and way smoother that the old V wheel/lead screw WB design,i also have pretty much Zero Slop/defection in the frame/axis, it's like a frecking Tank now!

Next project is a 4mm steel toped tortion box/waste board/bed + i have a Blackpill /STM32 controller on the way to replace the Uno..i'll post some stuff cut on it once i get those inplace.

Laters.

Corvus

That looks great, well sturdy!

Been debating CNC for a fair while, confident about the mechanicals but the software side looks very daunting.

TTony

Corvus said:

Been debating CNC for a fair while, confident about the mechanicals but the software side looks very daunting.

The software side *does* take some time to get your head around @Corvus if that's not your thing, and I find that I don't use it frequently enough to retain a lot of whatever I learn to make it do a job ... but for repeatable, very accurate and detailed tasks, it's absolutely brilliant.

Pick a software package that has good community support, decent YT channels, active user forum, frequent updates, etc.

Gizmo

Corvus said:

That looks great, well sturdy!

Been debating CNC for a fair while, confident about the mechanicals but the software side looks very daunting.

Yep it's much much better than the old wheel in grooves/leadscrew setup on the old WB clone kit i built, can wait to throw it at something major,most likely a Fretless version of the Brian Bromberg Bquad 4 string bass i own (minus the graphite neck!)

& As @TTony says it will take a little bit of time to get your head into the 3d space,but you can do a lot of work that just uses 2d layouts, so if your used to designing in PS with outlines all you need to do is tell the CAM software if it's cutting on the inside/outside of the curve, how deep to cut, how deep each pass should be and the cutting bit/type/size your going to use.

Someone asked me about the wiring of the control board/steppers and how hard it is to setup yourself,id say basically if you can wire up a plug you'll beable to wire the steppers/controllers without issue,once you've done one they are all the same wiring wise & your just attaching the pinouts to a different control axis.

I'll grab some video once i get a really cut going.

Gizmo

So, one small tip if your going to self build and config a home CNC...DO NOT USE the TB6600 Stepper drivers

After cutting all the inner body routes on this Ash sc 5 string bass without issue they lost stepping while 18mm down in the outside body pass (step over was 1mm so the bit wasn't rubbing/tight at all) and locked up the machine scary!.

I can recover/fix this piece by altering the profile for that aera by a few mm (i dont think it will look that bad or the other option is to fill and paint...)

I have some DM556 driver's coming as replacements,which now i look on YT for the problem loads of people have had issues like this with the TB6600 ir seems.....humm.

Sporky

Ouch!

Mine runs on Geckos. Which are interesting in their own right - particularly that with some encoders they then need resistors and capacitors bodging into the already-near-impossible-to-assemble IDCs at the encoder end.