[Che]

Another non-auto, non-Suzuki question.

In my downtime, one of my hobbies is to make guitar amps and pro audio gear. Most DIYers clone their favourite pieces of gear from eras gone by, but there's also a large base of guys who build their own items from scratch, or heavily modify circuits to the point it's virtually a custom solution. Once you start building your own circuits and designs it's impossible to find perfectly suited chassis and cases/enclosures for your projects. I'm usually using a dremel, jigsaw and stepped bits to make my own cases, but they're never as neat as a CNC cut piece. It's got me thinking I could possibly fill a niche as there's a reasonably big DIY audio electronics market but there's only one person in Europe that cuts and presses custom enclosures for hobbyists... and i've bought a couple of enclosures off him (@ $200 a pop) and was not overly impressed with the quality of what I received. Most people who are spending $1000 on components aren't wanting to hide their builds in almost-nice enclosures. The potential is also there to service businesses wanting batch runs of such products.

So here's a couple of examples of things i'd be interested in making. Sheet metal isn't really my forte so i'm not savvy with gauges, but the cases are usually made of mild steel or aluminium, anywhere from the thickness of a Sierra panel, and sometimes the aluminium is a light plate around 2-3mm thick. Of course, layouts, cutouts and enclosure sizes are dependant on the project at hand.






What sort of CNC machines would they use to cut out the these sheet metal panels? I know of plasma, laser and water jet CNC machines, but i've only ever seen them in fab shops from afar and have zero working experience with any of them, and I have no idea what would be best for the application i've described. I'm only used to working with plate metal and pipe. I estimate a cutting area the size of a pallet would be more than ample for what i'm chasing, but I have no idea if these machines are built on a small scale or only on an industrial scale. I also know they won't be cheap, but for now i'm just entertaining an idea.

Can anyone pre-school me on metalwork CNC machines?

[Zook_Fan]

The place to be if you want to learn about CNC stuff http://www.cnczone.com/forums/

For what you want to do I'd be going CNC plasma. For the work you want to do I'd say go with Air Plasma. It's the cheapest of the options you have presented and with the thickness of material it will be accurate enough. Machines are built on whatever scale you want and really aren't too dear. I costed this up only a couple of weeks ago and with a lot of overkill components for very decent accuracy and precision the CNC set up will set you back about $2k + a plasma. The plasma I costed up (Hypertherm 45) was around $2500+machine torch I think. You can do it cheaper on both scales as well. It depends what you use for you linear motion, what you use for drive and obviously you can set up much cheaper plasmas. You would have to look into torch height control, you can do it cheap but my costing includes a digitial torch height control from candcnc.com

Your other option, which could appeal to a higher end market, would be CNC router. Just as you said you've done in the past you could use the router the cut the profiles and piece them together or get a big slab of aluminium and let the router do it's thing. Have a read through that forum, it is really cool once you start looking into it. I'll be working on a CNC plasma in the not too distant future just for a side project.

With either a router or plasma you could also set up an engraver to travel on the y axis with it's own independant z motor. That way you could engrave all the fascia/text like in your examples with the machine as well.

[azzas15]

I don't know to much but if you took that into a shop that has a water jet I would imagine they would be able to copy or make something similar with any modifications you need

[henno]

I know a few places (ex clients) that have one of these machines:

http://www.salvagnini.com/

I've seen them pump out some amazingly intricate designs.

[Blakey]

i have a small desktop CNC machine that can do small stuff around the 200x200mm size also can do routing and engraving. it works well for doing custom PCB's and nearly any small scale CNC work if you have the right milling or routing or engraving bits.

got it off ebay i can't remember how much tho.

depends on what size you need it might be cheaper to buy your own small ones and go from there.

[Reubs]

If you are putting cutouts into rack faceplates and need something neater than stepped drill bits, how about something like a powerman junior. We use these at work and they are pretty easy to get really neat cutouts in panels. We mainly use these for up to 50mm dia holes into 2mm mild steel sheet. These are commonplace in the switchboard industry. There are also dies available for them which will do square cutouts although I personally have only used them to cut round holes.

http://stainelec.com.au/doc/HP-1_Specification_Sheet.pdf

[Blakey]

Iv used them at work they are pretty dam awesome I must say and so much less effort than a holesaw or similar

[Che]

Thanks for the advice guys. I'm gonna join that CNC forum and see what they recommend. I might be able to set up a little cottage industry to keep me busy between projects.

[SierraDan]

Plasma cutter isnt very good at the smaller details like those small holes.

[Che]

I think a CNC router is my best bet, that way I can tweak a machine to work wood also. Supplying pre-cut panels for guitar amplifier cabinets and speaker boxes is another service I could provide. It also seems to be the cheapest option in terms of maintenance and running costs.

[alien]

I'd love a small CNC machine =) be so fun!

[Blakey]

this is my little desktop CNC Router.

i pretty much never use it haha its still brand new. has a rotary tool that's clamped to it. and the rotary tools drive head has been replaced with a chuck bit. for accepting milling bits and engraving bits

payed around 700 for it. when i bought it so if your after this size expect around that price.

[sideways]

alien wrote:

I'd love a large CNC machine =) be so useful!

[31zook]

SierraDan wrote:

Plasma cutter isnt very good at the smaller details like those small holes.

Laser cutting is what I use for my stuff.

Laser also doesn't put allot of heat into the job, so your 0.6tin sheet doesn't buckle while cutting.

[nick_75au]

Ive got a mate who does custom dashes for cars and boats using aluminium plate, he uses a Multicam CNC router, If you can do Cad, it might be better to farm out the work. he charges about 100 for a smallish dash including either paint or graphic coat.

nick

[ball]

31zook wrote:

Laser cutting is what I use for my stuff.

Laser also doesn't put allot of heat into the job, so your 0.6tin sheet doesn't buckle while cutting.

Laser isn't that flash on aluminium. I have never found anyone to do a decent clean cut with ally.

[mnemonix]

Without hijacking the thread, does anyone have experience with the Sieg benchtop mini mills?
I'm love the idea of being to whip up my own flanges/bushes and small parts out of mild/ally/stainless. I believe these can be DIY converted to CNC?

[31zook]

ball wrote:

31zook wrote:

Laser cutting is what I use for my stuff.

Laser also doesn't put allot of heat into the job, so your 0.6tin sheet doesn't buckle while cutting.

Laser isn't that flash on aluminium. I have never found anyone to do a decent clean cut with ally.

My grinder does a good job

But seriously, I think it has to do with its oxidizing coating. Without prepping the surface, the Inside of the ally takes on heat before the outside layer does.

So water jet might be the best option for ally as it doesn't use a current to cut.

[henno]

ball wrote:

Laser isn't that flash on aluminium. I have never found anyone to do a decent clean cut with ally.

Hmm... In commercial environments it works just fine. Some of my biggest clients were exclusively laser cutting businesses and the cut quality was just fine. Plasma maybe not so much.

[shep]

What you fellas consider to be just fine won't be the same as what ball considers to be just fine. It is either perfect or it's shit.

[ball]

mnemonix wrote:

Without hijacking the thread, does anyone have experience with the Sieg benchtop mini mills?
I'm love the idea of being to whip up my own flanges/bushes and small parts out of mild/ally/stainless. I believe these can be DIY converted to CNC?

Build thread

http://www.ausrocketry.com/forum/viewto ... =32&t=4002

[ball]

31zook wrote:

My grinder does a good job

But seriously, I think it has to do with its oxidizing coating. Without prepping the surface, the Inside of the ally takes on heat before the outside layer does.

So water jet might be the best option for ally as it doesn't use a current to cut.

I don't want to have to touch the part after cutting. If I pay to get something cut then it needs to be complete. You wouldn't get a dirty old boilermaker to oxy cut parts out and have them leave the snot on the cut would you

The last guy I spoke to it about said it was a reflectivity problem. I have noticed that stainless is usually done with the plastic still on it. I asked if they would try and cut it if I painted it first but they weren't keen.

[ball]

henno wrote:

ball wrote:

Laser isn't that flash on aluminium. I have never found anyone to do a decent clean cut with ally.

Hmm... In commercial environments it works just fine. Some of my biggest clients were exclusively laser cutting businesses and the cut quality was just fine. Plasma maybe not so much.

not really,

I have used 3 or 4 different ones around Australia over the years and aluminium isn't a clean enough cut without having extra finishing work.

[ball]

shep wrote:

What you fellas consider to be just fine won't be the same as what ball considers to be just fine. It is either perfect or it's shit.

It doesn't need to be perfect, it just needs to be right

[31zook]

There isn't much complaining with hammer marks in their head

[Che]

So what CNC programs are worth investigating? Preferably cheap, or better yet - free. I want to see if I can get my head around the CAD side of things.

[alien]

fyi, thepiratebay has moved domain to .AC now... =)

[henno]

Not for long. I give it a week before they move on to a non-UK controlled TLD.

[nowie]

Che wrote:

So what CNC programs are worth investigating? Preferably cheap, or better yet - free. I want to see if I can get my head around the CAD side of things.

i only know wood one as i used to make cabinets with them, but there is woodwop (the program that homag CNC use) what you can trial download it will let you draw basic stuff to get you head around the programming. the program i used was biesseworks another real easy to use cnc program but from memory its quiet pricey and basically pointless if you don't have the cnc to transfer the program to it.

have fun programming

[mnemonix]

I've been looking at Mach3. Seems pretty easy to use, and cheap ($200) or free (old version via torrent).
You can download demo's to use that have full functionality but are limited in program length.

Also found a few free tools to convert .jpg/.bmp to gcode if you want to really simplify your drawings.