MUFF WIGGLER Forum Index
 FAQ & Terms of UseFAQ & Terms Of Use   Wiggler RadioMW Radio   Muff Wiggler TwitterTwitter   Support the site @ PatreonPatreon 
 SearchSearch   RegisterSign up   Log inLog in 
WIGGLING 'LITE' IN GUEST MODE

Securing a PCB to a faceplate.
MUFF WIGGLER Forum Index -> Music Tech DIY Goto page Previous  1, 2, 3 [all]
Author Securing a PCB to a faceplate.
ericD13
ericD13 wrote:
Nobody mentionned pot mounting bracket.
I don't find them on mouser.
Are they myths ?


I answer myself : they're real !

I found them at cesyg's pot brackets
Dego
I love this thread love
iopop
Same here, this one is pure pr0n. hyper
sduck
ericD13 wrote:
Nobody mentionned pot mounting bracket.


Probably no-one mentioned them because they're one of the worst ways to mount a pcb. Puts too much stress on the pcb when and if the module gets dropped or jostled. I've built a few modules using this method, and had to repair more than one of them after some incident that mounting on a regular bracket would have avoided. In almost all situations where pot mounting brackets could be used, you could instead use a regular panel type bracket that is held on by the pots, and run wires to connect the pots or whatever to the pcb - much more robust in the log run!
wsy
JB-weld is just a good quality steel-filled epoxy. It sets up very hard and has very good
peel strength - but there are a hundred other brands of what's basically the same thing.

You might need to take the train ride over to Copenhagen but Malmo used to have a
pretty good industrial base and you should be able to find steel-filled epoxy there.

One hint: use a rotary tool (Dremel or equivalent) to grind up the surface where you're
going to put the epoxy - and grind it *just* before you mix the epoxy, and don't touch
it after grinding. The rough, unoxidized surface will bond really well to the brackets.

Another hint: if you have more than one bracket on the same panel back, bolt the
brackets to an unstuffed PCB (or something with holes in the exact same place),
and use that as a positioning jig to make sure the brackets are lined up and at the
correct distance (which means the PCB won't be stressed when mounted).

And do use wires between the pots/switches and the PCB, to avoid ripping the traces
right off the PCB.

- Bill
synthcube
I could be wrong but I think bridechamber/stooge are steel? Fonik uses steel as do many others etc... just curious to hear opinions.
fonik
i used sttel, however, i used aluminum, too. aluminium burns much easier than steel (1200degC, i guess), but hey, i don't care...
neil.johnson
ericD13 wrote:
ericD13 wrote:
Nobody mentionned pot mounting bracket.
I don't find them on mouser.
Are they myths ?


I answer myself : they're real !

I found them at cesyg's pot brackets


Please note that page has moved to a faster server:

cesyg's pot brackets

Thanks,
Neil
pugix
The MOTM (Bridechamber) brackets are steel. This is fine, as long as the panel exactly meets your needs. But steel is tough to cut and drill. I've been making small brackets using thin sheet aluminum from Lowes. Not sure of the thickness, but it's thin enough that I cut it by scoring deeply with a utility knife and bending till it breaks. It is really easy to drill (and file when your holes are a little off). Once you put a bend in the aluminum panel, it is fairly rigid.

Example projects using the thin aluminum:

http://pugix.com/synth/mattson-vcf/
http://pugix.com/synth/dual-resonant-gate/
http://pugix.com/synth/modular-tetrazzi/

For CGS projects, I have often used Bridechamber steel brackets, since they are pre-drilled to match Ken Stone's PC boards.

http://pugix.com/synth/cgs-serge-vcs/
thetwlo
any reason to not use the cheap steel lath from places like Home depot? bends easily, can mount anything to it without drilling, can flatten easily.
sturdy, yet easy to bend.
http://www.homedepot.com/p/27-in-x-8-ft-Steel-Lath-2-5-METAL-LATH/2020 93395#.UfTJSKvEq8J
pugix
About the cheap steel lath, I'd wonder how easy it is to make holes for mounting boards, as well as how sturdy it is when you bend it 90 degrees. That's my basic technique for imparting some sturdiness to the thin Lowes aluminum stock. Make a right angle bend, usually where pots will go through to mount a panel. That bend will stiffen the material along one axis. It can still flop back and forth along the other axis, but if you affix a small PC board, that also increases the stiffness.

In general I don't like to work with steel, because it is hard to cut and bend, and when drilled produces sharp, dangerous filings.
keninverse
For brackets I use K&S model aluminum sheet with a thick enough guage that does not bend. It's soft enough to drill but rigid. When I need to make a perpendicular angle, I just score with a formica scoring knife a few times then bend it with a vice and a piece of wood molding. Works for me. The aluminum sheets come precut to a sizer perfect for Euro (comes in 12" x 6" sheets) so I only need to make one cut with a hacksaw.
hexinverter
I made this little video showing how I do it smile

Cablebasher
Hey fellas,

So I have decided to go down the sheet metal cut with tin snips and drilled holes for mounting pots route as suggested.

Any advice on the drilling process? My drill has only ever been used for wood so far, I guess I'll need a special drill bit and maybe a vice for safety?

Thanks as always.
mechie
Cablebasher wrote:

Any advice on the drilling process? My drill has only ever been used for wood so far, I guess I'll need a special drill bit and maybe a vice for safety?

The drill bits I have (very common type) are happy with wood, metal, plastic... anything but masonry!
One word of warning...
When drilling this really thin metal (steel and alu, applies to PCBs as well) when the the drill bit breaks through the material it will try to 'corkscrew' the board, sheet, whatever up the drill's shaft. THIS is when there will be a sudden 'snatch' and the drill will try to spin the sheet, slicing all in its path
Viking
Don't use too much force to push the drill through the sheet, let it take its time.
I ALWAYS smooth the metal sheet's edges and corners before drilling so it is less likely to slice when it does go wrong (and eventually it will) waah
If you have the option, use a low drill speed so it is less likely to launch your bit of steel across the workshop.
Hold the workpiece firmly, expecting it to 'snatch'.
Be prepared to just let go if the drill does grab - don't try to catch it, let it stop spinning first.

If you only have a pistol drill (a hand-held drill) then it may be safest to put your workpiece on the floor with a bit of wood below it. STAND ON IT whilst drilling. Expect all the above problems.
Ideally, drill first, cut to size after, then there is more to STAND ON!

I use aluminium sheet for brackets, I say the above from experience!
Don't be scared off though - just be prepared!
mskala
mechie wrote:
One word of warning...
When drilling this really thin metal (steel and alu, applies to PCBs as well) when the the drill bit breaks through the material it will try to 'corkscrew' the board, sheet, whatever up the drill's shaft. THIS is when there will be a sudden 'snatch' and the drill will try to spin the sheet, slicing all in its path


I wouldn't drill metal without clamping it firmly in place with C-clamps, a vise, or both. Going handheld is not only dangerous, but inaccurate.
mechie
mskala wrote:
I wouldn't drill metal without clamping it firmly in place with C-clamps, a vise, or both. Going handheld is not only dangerous, but inaccurate.

So you don't centre-pop your holes then?
roglok
Cablebasher wrote:

Any advice on the drilling process? My drill has only ever been used for wood so far, I guess I'll need a special drill bit and maybe a vice for safety?


i use a step drill, such as these:



you start with a small pilot hole, then gradually drill it up to the desired diameter. the type pictured above will also act as a deburrer.

initial investment may be high, but well worth it imho...
mskala
mechie wrote:
mskala wrote:
I wouldn't drill metal without clamping it firmly in place with C-clamps, a vise, or both. Going handheld is not only dangerous, but inaccurate.

So you don't centre-pop your holes then?


I use a centre punch, but even so I don't trust myself to keep a handheld drill on target without clamping the workpiece.
aladan
roglok wrote:
Cablebasher wrote:

Any advice on the drilling process? My drill has only ever been used for wood so far, I guess I'll need a special drill bit and maybe a vice for safety?


i use a step drill, such as these:



you start with a small pilot hole, then gradually drill it up to the desired diameter. the type pictured above will also act as a deburrer.

initial investment may be high, but well worth it imho...


Step drills are awesome! The only thing better is a CNC machine smile
davebr
I make all my panels out of 0.050" aluminum. I ended up buying a full sheet so I have a lifetime supply! I bought 5052-H32 which is fairly soft. 0.050" thickness works well with potentiometers, jacks, and mini-toggle switches. I have seen small 0.050" aluminum sheets in hobby stores.

Originally I used pneumatic shears to cut it. It is a little challenging to cut it straight so I made a wooden guide.


Originally I would clamp the aluminum between two steel I beams and then hammer it to 90 degrees. I ended up buying a small Grizzly brake for better bends. I also bought a small Grizzly corner shear. I tend now to rough out the aluminum with the pneumatic shear and then finalize it with the corner shear. I can only cut a 6" section so longer pieces require multiple cuts. I also work on cars so the brake and shear help there as well.


Most brackets are simple bends. I mark and drill the bracket slightly smaller than the finished hole. In the case of 3/8" potentiometers I drill up to 5/16". Then I drill the center hole to 3/8" and mount the panel to the bracket with one control. Then I carefully drill the remaining holes out with a 3/8" drill from the front so the bracket holes are perfectly aligned with the panel. There isn't much material so there isn't much waste, but the waste is coming out through the top so you need to be careful to not scratch the panel. Step drills are nice for roughing the hole up but you have to be careful to not drill too far. I usually wrap tape around the drill where I need to stop. After using the drill for a bit the size information wears off so I have to measure to verify.


In the case of my latest panel, the rotary switches I used were a bit too short to mount the panel with so I mounted it with the three mini-toggle switches. I had to notch the panel to clear the rotary switches and also one of the mini-toggle switches so I could wire it. I used the corner shear for the rotary switches and a hand nibbler for the toggle switch openings.


My MiniWave had a top mounted PCB and I wanted to have this mount on the bracket so I needed a three sided bracket. I bent the standard L shape and then brazed another aluminum piece on top. This is probably my most complex bracket because of the brazing.


I put a lot of effort into making a robust sturdy bracket. It is the foundation for a reliable module.

Dave
MUFF WIGGLER Forum Index -> Music Tech DIY Goto page Previous  1, 2, 3 [all]
Page 3 of 3
Powered by phpBB © phpBB Group