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demonx

So this is where the cnc guys hang out?

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Exactly. Pouring all your time and effort into achieving the "gold standard" right off the bat will start up cause you endless amounts of "non-productive" time. Even using the CNC to produce templates and parts for jigs will immediately improve output usefully whilst simultaneously not giving yourself a mega-steep learning curve.

This autumn I want to hit the guy running our CNC in the head and face area a bit. Then I want to start working on creating a familiar workflow without having to continually involve his lazy ass.

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I use SolidWorks exclusively. It's way overkill for just doing guitars, but there's definitely no better tool for it. Plus the fact that there's a free CAM plugin, HSMXpress. It only does 2.5D stuff, but it's very good, very intuitive, and you use it in the SolidWorks environment, so when you make a change to your model, the toolpaths are automatically updated.

The cost for a SW license was tough to swallow (just over $4k, and that's without the subscription service), but it's proven to be well worth it.

I'm no guru by any means, but feel free to hit me up with any questions.

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Thanks DC, I've had a lot of progress over the last couple days, I've basically got my Solidworks models up to the the stage (only a couple of them) that I had my autocad ones.

It's more a transitional thing at the moment, in autocad I know how to approach things, in SW I have to work out how it approaches the same task, for example at the moment I cannot work out why a certain thing won't trim and it's frustrating to say the least. It should trim as I've created a surface to use as a 3D cutting tool, which succeeded, now i can't trim it to the edges, which I cannot make sence of.

Then the whole planes and sketches thing keeps confusing me. I'm starting to get used to the sketch aspect and swapping from sketch to sketch but the planes thing still pisses me off.

I'm learning though. Every time I sit down to it I'm learning something and most times I get over a hurdle that I couldn't jump the time before.

Another thing that is slow progress is I'm redesigning my shape slightly to my handmade shape. So that is also slowing down progress as I work out the design aspects at the same time I learn the software.

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I managed to jump a few more hurdles today that have been slowing me down.

One of my main obstacles was the neck to headstock transition. It felt practically impossible with Autocad. I managed to get this done today with Solidworks.

10481615_663155090432995_616900079314156

10464385_663151780433326_205641112940988

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More baby steps.

I cannot finish the neck heel until I finish the body.

1511760_664103337004837_9038339286429408

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Re, modelling the complex shapes:

Have you considered physically making some of the difficult parts (eg, headstock-to-neck transition) using pine, MDF or other cheap materials by hand, slicing them up into 5-10mm cross sections, laying them on a scanner one by one and joining all the cross-sectional 2D scans into a 3D profile? I'm thinking kinda like putting the skin on a boat hull.

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Or you could just use a contour gauge. I bought mine years ago for about $20.00

I've only used it on the neck profile itself though, the test of it I've modelled to sight and will modify it after I start cutting wood with the machine

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Contour gauge is a good non-intrusive idea, although it might be more difficult to get accurate results on areas where the profile changes rapidly over a short distance (neck to heel transition for example).

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Have just been talking to the guy building the CNC and all the issues that have been holding it up have been overcome and all the mockup parts and wiring have been removed and the final parts are now being assembled with the correct wiring etc.

I've been told it's only weeks away now.

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That's a decent sized beast! How big is that bed?

SR

I cannot remember the final spec as it has been enlarged from the original list, but it's about the size of a small car, the cutting area is obviously less, but it's enough I can lay a house door in and carve it.

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Ok, it's here, finally, so now what do I do!

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Well, actually, yes, it's here, but Mach 3 still needs to be set up completely and some issues with the tool changer not resetting correctly after a power down or reset. The guy who built it is still trying to sort out the codes he wrote to fix that as the code written by the spindle company was not compatible with this machine for some reason I don't understand but I'm guessing the engineer who is building the machine would not spend the time to write codes for nothing when he's not getting paid extra for it.

Another major problem at the moment is the spindle is faulty. The tool changer is not releasing and the water jacket is leaking and water dribbles out the bottom of the tool holder area. Spindle company have acknowledged this is a fault and says they're building another one and it'll be shipped in a couple of weeks. Bad news is their "fast service" last time took them six months to deliver the current spindle, so no idea how long they plan to take this time. Lets hope it's sooner rather than later and at the moment we're looking at some temporary spindles just in case.

All that aside, it looks like I now need to learn how to use this thing and I'm guessing it'll be a major task. My brain hurts already and I haven't even learned how to turn it on!

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Time for some updates.

Turns out the CAD software I'm using (Solidworks) doesn't like the CAM software I had (Aspire), so I've had to move over to CamWorks which is a way more advanced system, but it integrates itself into Solidworks which is great.

You can see from the pics below the difference the two CAM packages make the way they read the Solidworks file. Exact same file, same cutter, same idiot running it, just a different CAM program generating the code.

My biggest issue at the moment is writing the Post Processor, as CamWorks does not supply a P.P. for Mach3, as Camworks is written for 300k machines and Mach3 is generally for hobby use, so I'm using a generic Fenec Post and trying to modify it myself, which when I don't understand G-Code or Post Processor code is quite a chore. I've got one running, but it's very glitchy.

Another issue is the proper spindle is not here (this one is faulty) so the tool changer isn't functional at the moment. The spindle works, but the water jacket leaks, so it can only run air for cooling and the tool changer doesn't release. The manufacturer has viewed a video of the fault and is sending a replacement, this one to be returned when it arrives.

IMG_9525small_zps7f56b78a.jpg

IMG_9524small_zpsda211b30.jpg

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If you're desperate, I could probably help you configure Solidworks to produce those weird compound shapes that only Aspire seems to be able to manage! ;-)

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CamWorks is supposed to be excellent. Couldn't afford that price tag on top of SW, so I opted for HSMXpress (a free 2.5D plugin from Autodesk). Super easy to understand. I use the generic Fanuc post as well, and it works brilliantly.

For 3D carves I use FeatureCam. It's kinda cheesy, but it does a good job, just not as fluidly.

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CamWorks is supposed to be excellent. Couldn't afford that price tag on top of SW, so I opted for HSMXpress (a free 2.5D plugin from Autodesk). Super easy to understand. I use the generic Fanuc post as well, and it works brilliantly.

For 3D carves I use FeatureCam. It's kinda cheesy, but it does a good job, just not as fluidly.

I've spent the last few days trying to work out CamWorks, yes, it's awesome, yes, there's feature upon feature, menus inside menu's inside menus! I'm sure it's all great once you know the program inside out, but trying to learn it from scratch is a giant undertaking.

It has some feature recognition features that you can pre save strategies for, I'm trying to get these sussed out at the moment but the program keeps overwriting my settings with defaults and keeps choosing its own tools as opposed to the ones I've selected from my own tool crib.

Once I get over these hurdles I can move onto bigger ones, like getting the Post working properly. At the moment it's working and I'm able to use the machine, but there are few things I'm not happy with still, for example it isn't turning the spindle off before it returns to home, now on my machine returning to home is something like 3 meters of diagonal travel, I'd rather the spindle be turned off!

Take this for example:

I want the spindle to lift up 50mm when I hit start. At the moment I set the workpiece zero and hit start and then it moves dragging the bit across the workpiece.

I added this z50 to the "init tool change" section (whilst creating the Post Processer in UPG), however when I run this code on the machine it lifts the Z to the limit (which is about 300) rather than just 50mm - in G-code to lift the z 50mm I just write z50, but how do I write it in the UPG code?

:T:<N><TOOL_COMMENT><EOL>

:T:<N><T><M:06><EOL>

:T:<N><G:00><Z50><EOL>

:T:<N><S!><M!:SPINDLE_DIR><EOL>

Next question, because I've added it here, I think it'll do it at every tool change, so where should I actually be adding it, I want it to lift at the beginning, just before the spindle starts.

Here is my default "start of tape", should I have it in here?

:T:O<"%4LT": program_number><EOL>

:T:<N><G:17><G!:ENGMET><G!:40><G!:80><EOL>

Next question, I've added this M:05 to the end of tape to turn the spindle off - at the moment when the workpiece is finished, the spindle lifts, moves to the machine zero and then the spindle turns off, I want the spindle to turn off before it returns to zero (safety first)

:T:<N><G:00><G:91><G:28> Z0<EOL>

:T:<N><M:05><G:28> X0 Y0<EOL>

:T:<N><M:30><EOL>

It looks like it should work, but it's not! So why isn't this working? Or do I need to add it somewhere else? All the G-Code still looks cryptic to me.

Is there anything else I need to add to a Post Processor that I haven't thought of yet that is just good machining practice or things that are advisable?

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