The bane of my diy audiophilia ...

[mirlo]

... is metalwork, making decent enclosures.

If I had the knowledge and tools, or even the knowledge about how to go about learning and acquiring the tools, and the technique to produce nice metal cases worthy of the excellent circuits one can learn to build by reading these forums, my life would be so much sweeter.

I wonder if enough interest could be generated in such a topic to warrant a new forum about metalwork, and the craftsmanship of the physical construction of good electronic equipment.


Meanwhile any suggestions about how to get started would be welcome. I sometimes think about taking a metal shop class at a community college, if such classes even exist any more :-(


-- mirlo

[eplpwr]

Hi!

I've had the same problems, but found a way to solve them: Use a hobby-sized CNC. Since you have the privilege of living in California, you can check out http://www.sherline.com , really nice products, and you probably pay less pricey freight charges compared to what I did... I use my machine both for small metalworking (cutting, drilling, milling) as well as PCB drilling and milling. This machine has made it possible for me to do stuff I never thought about before. The only limitation are the maximum size of whatever you're doing; some things have to be made as sub-parts and then joined together.

I'm using the LinuxCNC software, which is 100% free! It takes standard G-code as input (RS-274NGC), which you can find information on by searching the 'net. Installation time for LinuxCNC was approx 15 minutes, and four hours editing a configuration file (text format) to make it compatible with the motor controllers.

Edit: The site is called http://www.linuxcnc.org , and the software is called EMC - "Enhanced Machine Controller". Look for BDI - Brain Dead Install, it will allow you to test the S/W running from CD-ROM + Memory only (no harddisk involved), or you can tell it to install to your harddrive for a permanent setup.

Regards,

[mirlo]

wow, that is some interesting stuff..

which machine(s) did you end up with?

what kind of things have you built with it? What size limitations does your setup have?

[eplpwr]

I bought the 2000 series mill, and the 4100 series lathe, both CNC-ready (stepper mounts). I also bought the stepper motors separately. To control the steppers I made some 4-axis control boards using Allegro Microsystems A3977 chips. The reason I didn't go for the complete CNC systems is that it would just have got complicated to ship a PC to Scandinavia, and the shipping+VAT would have skyrocketed. In your case, since you have Sherline close by, I would recommend getting the turnkey CNC package.

After the initial machine purchase I've pretty much added every accessory in their book to my setup, you just "have to have" certain accessories...

I've built some enclosures, where you make sure that some parts like the top and/or bottom of a box matches some pre-cut sheet size, then you can make front, rear and side panels yourself. You can also machine standoffs, connectors ... well, everything sufficiently small. If needed the parts can then be electroplated to get a nice or corrosion resistant finish. 'Al' is the preferred metal (I don't dare to spell out that word since there are different spellings available).

Another completely different thing I've made is signs out of hardwood (oak, teak). It started with one sign for our front door and then someone asked where I got that sign...

All the best,

[eplpwr]

Sorry, forgot to answer on size limitations in previous post.

The absolute maximum sizes (=movement max) can be seen in the comparison table at: http://www.sherline.com/mills.htm . In real life I can do something like 8" (X) by 5" (Y). The Z capacity is most often limited by what tool you have (cutting length). Too long a mill is not good either, a 1/4" mill that has a 2" cutting length is quite unusable, since it will flex too much. I have some 10 mm (approx 3/8") mills that have a cutting length of 35 mm, and they work fine as long as I'm not cutting too much in a single pass.

The larger (diameter) tool you use, the more limited you'll be on the size (X and Y, that is) of the part you're working on, since most often you will machine the part on both ends, and you need to "make room" for the tool on each end.

Happy CNC-ing,

[bob_v5]

i use a hacksaw, files etc, can make nice stuff that way. cheper than buying cnc gear, but takes much longer. Not too difficult but requires patience! old analogue sattelite decoders make nice boxes, sometimes i just use one of them with an aluminium front plate. im sure i spelt that wrong

[valveitude]

CNC is awesome if you can afford it, but you can do amazing things with basic hand tools if you know how...like building a CNC machine if your so inclined.

Check out Lindsay's Technical Books , he specializes in re-printing all kinds of shop books with expired copyrights. This is were I learned most of what I know about metal working.

Casey