Slotted enclosures for long-throw sliders?

Started by inverseroom, April 04, 2005, 09:42:01 AM

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inverseroom

Like the ones on the EHX microsynth.  Yes, I know these are custom made for EHX, but does anyone make pre-slotted aluminum boxes?  And if not, what's the simplest way to cut slots, using common tools?

I'm hooked on the idea of buying a few of these from Mouser and making a little 3-osc CMOS synth type thing.

Vsat

Saw this in a mag - disclaimer - haven't tried it yet:

Start a slot by drilling  a series of holes side-by-side. Then clamp two or three hacksaw blades side-by-side so it looks like a single hacksaw blade of double or triple thickness. Fit this into the starter-slot and start cutting.
Cheers, Mike

bwanasonic

I can't think of any real advanatge to using sliders, other than to invoke the EH microsynth. As a someone who used the EH unit for years, I can advise you use sliders that are somewhat protected, rather than open like the EH. The crud that would build up in that thing was scary.

Kerry M

inverseroom

Quote from: bwanasonicI can't think of any real advanatge to using sliders, other than to invoke the EH microsynth. As a someone who used the EH unit for years, I can advise you use sliders that are somewhat protected, rather than open like the EH. The crud that would build up in that thing was scary.

Kerry M

Yeah, I intend to put the shaft through a slot in a piece of felt, like on the Juno-60..

The main reasons I want to do this are 1) hardly anyone else does, 2) tactile satisfaction, and 3) you can always see very easily what position every parameter is in.

Anyway, the hacksaw idea sounds like a good one.  I may also try the little rough sanding/cutting disc on my dremel...

Mark Hammer

However you would choose to do it, I would strongly suggest working with aluminum only since the softness of thematerial enlarges the number of options for cutting.

It IS possible to get what you might call milling bits for dremels, that will let you clamp the dremel and slide the panel along a jig to mill out a straight line.  Ideally, for keeping the panel as rigid as possible, and the point of entry for dirt as small as possible, you aim for the narrowest slot you can achieve.

If wider slots are your bag, nibblers can also be used occasionally, though they are admitedly a bit less convenient to use and harder on your hands and wrists.

dpresley58

A slot narrow enough just to allow the throw lever to protrude through the top if its long enough? Good idea... Then, a small strip of thin rubber with a slit in it could be mounted inside the box to alleviate some of the trash getting into it.

Just a thought.
Little time to do it right. Always time to do it over.

Paul Perry (Frostwave)

Maybe a mini angle grinder would cut a slot?
Sounds dangerous, but with the right setup,
I can imagine cutting slots in aluminium boxes.

Or, for a one-off, maybe a local engraver could do it?

R.G.

a) drill a line of holes and saw the rest, as noted
b) drill two holes, one at each end of the slot, then cut between them
c) set a thin-kerf, carbide tipped blade in a radial arm saw; raise the carriage until the blade clears the box. Place the box under it and ... carefully... clamp it into place. Put on full-body protective gear, including especially your eyes and lower the blade into the box in tiny increments, having a friend standing near the breaker that controls the saw incase anything goes wrong. (N.B. you can use a circular saw to cut mild aluminum, but it's a scary, pyrotechnically advantaged proposition). No, on second thought do not do this.
d) ferric chloride etches aluminum much faster than it etches copper. You could paint the entire box with lacquer, let it dry, then scrape the lacquer off where you want to have slots, then etch. N.B.: this is an outdoors task. It is also pyrotechnically advantaged. Chemical protection is mandatory.
e) get a small milling machine from Harbor Freight and mill the slots.
f) get a scissors type sheet metal nibbler and nibble the slots if the aluminum is thin enough.
R.G.

In response to the questions in the forum - PCB Layout for Musical Effects is available from The Book Patch. Search "PCB Layout" and it ought to appear.

Peter Snowberg

This isn't too DIY friendly unless you live in the right location, but waterjet cutters do a BEAUTIFUL job cutting anything you want right from an Adobe Illustrator file.
Eschew paradigm obfuscation

inverseroom

Quote from: R.G.c) set a thin-kerf, carbide tipped blade in a radial arm saw; raise the carriage until the blade clears the box. Place the box under it and ... carefully... clamp it into place. Put on full-body protective gear, including especially your eyes and lower the blade into the box in tiny increments, having a friend standing near the breaker that controls the saw incase anything goes wrong. (N.B. you can use a circular saw to cut mild aluminum, but it's a scary, pyrotechnically advantaged proposition). No, on second thought do not do this.

:shock:

I think I'm gonna with Paul's suggestion since this is a one-off.  It'll be a thin aluminum enclosure--first I'll try the mini-grinder on my dremel, then if that doesn't work, my larger grinder, which I last used to get the rust off a secondhand iron bathtub.  I will wear protective eyewear!  And of course an asbestos jumpsuit!

Paul Perry (Frostwave)

Be careful inverseroom! make sure that box is clamped really tight.
And  :shock: WARNING WARNING :shock: note I havn't ever done this myself.

Mike Burgundy

Try this on for size:
get a drill-press, and a drill with a head that will hold router bits in the appropriate sizes. Shouldn't be too hard. Just make sure both the press and the drill (esp. the drill) have as little lateral movement as possible.
Clamp (or bolt) the drill press to a nice and flat table, as far away from the edge as ypou can get it or need it (which ever comes first)
Install a guide rail parallel to the edge of the table, as close to the base of the drill as you can get it.
Make a series of distance templates, that you will use to determine *where* the stationary router bit will actually cut by placing the object at another distance from the drillpress base.
Using the templates and the guide rail, rout very accurate grooves wherever you want them. Make sure you don't put much pressure on the cutting bit as this can push/bend the entire assembly. Take your time.  I fthe table and rail are nice and smooth, the vibrations of the router will actually make the object glide along really smoothly. These setups will always flex a bit - the trick is to apply a CONSTANT amount of pressure and speed, so the bit is always in the same position.
Remember that if you're cutting, the bit wants to move *towards* it's hard-cutting edge (anti-clockwise cutting bit will push down when feeding the object right-to-left...so the bit will want to cut downwards, the object will want to go up). The bit just wants to dig in. Confusingly, a blunt bit will want to move *away* from it's hard-edge. It doesn't want to cut through the material as eagerly, preferring to go off home and have a beer and a late-night movie ;)
Some bits have a different cut and will promptly react differently. After a bit of practice, you can get *vey* accurate (results on a par with the scientific router bench we have at university. at least for the specifications WE pedalbuilders/guitarbuilders/musicians/generally-not-so-anal-people need, anyway)
I even use this method to rout truss-rod slots. I'd say it's accurate enough - if your template is good and you take it easy..

hank reynolds 3rd

drill two holes, score a line with a stanley knife and keep slicing away with said knife until you have a slit....and watch you hands dont slip...(i know this sounds a bit silly, but i used this method to cut slits for switches once...and i got a scar waaayy too close to my wrist to prove it)

:oops:

Sam