Keep from drilling your enclosures wrong

Started by cbgpedalmaker, April 21, 2016, 11:12:55 PM

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cbgpedalmaker

I don't know about you guys, but given that the enclosure is most of the time the most expensive single part of my build, it's frustrating when I screw one up. I'm currently in a CAD class. I thought that I'd use my skills to help make sure that my enclosures are drilled right. This is a pdf of a drawing that I made in LibreCad. The enclosure here is a Hammond 1590BB. I'm just showing the top, right side and front view here. This isn't supposed to be an exact engineering drawing, but just to help with drill placement. If anyone else is building pedals with a Hammond 1590BB with 2 or 3 pots you can use this layout to help you. The hidden (dotted) lines are there to make sure that everything fits. The big dotted square is the pc board. Obviously the depth of the pc board includes the standoff, but not the components. I figure that you would have to make sure that your board layout is compatible with this. If anyone would like layouts/drill placements for other enclosures I would be willing to help with that when I have the time. Just let me know the type of enclosure and what components you are using. https://drive.google.com/open?id=0B3dHrF1yIrmrd3gtaHFOMnBXdzA

Gentle Jack Jones

Thanks for posting this. I'd love to see one for a 1590b. Like you, I find getting the drilling right to be one of the harder parts of pedal building, and getting it wrong one of the most expensive mistakes!

deadastronaut

i tend to print off a scale template of all drill holes on the face, tape it to it

and centre punch the 1mm drill dots,...pull it off..

drill  small pilot holes..then the bigger drill bits come out..no wobbly holes.. ;)


(if etching , the etch design has the holes too) handy.. 8)

the sides and dc come after..

https://www.youtube.com/user/100roberthenry
https://deadastronaut.wixsite.com/effects

chasm reverb/tremshifter/faze filter/abductor II delay/timestream reverb/dreamtime delay/skinwalker hi gain dist/black triangle OD/ nano drums/space patrol fuzz//

Kipper4

I'm with the space cadet. I print off a low ink black and white copy, mark off the holes and Pilot drill.
Thanks for sharing.
Ma throats as dry as an overcooked kipper.


Smoke me a Kipper. I'll be back for breakfast.

Grey Paper.
http://www.aronnelson.com/DIYFiles/up/

R.G.

Here's an idea: do the four side views, and then place them together with the top view, printable on a sheet of paper, real size. Then you could cut out the paper template, and wrap it on the actual box, then as deadastronaut says, tape it to the box and center punch your hole locations.

Much like this template for the 1590bb from 1999 at geofex.com.
http://www.geofex.com/FX_images/hmbbtpt.pdf
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.

karbomusic

#5
Quote from: deadastronaut on April 22, 2016, 03:56:37 PM
i tend to print off a scale template of all drill holes on the face, tape it to it


^This. I use Photoshop (Inkscape works just as well) to hold my outside graphic design, internal part sizing and placement as well as drill points all in the same document via layers. This includes the side view/holes etc. Since the print is to scale, moving parts which may change hole placement etc. is all taken care of. Once all is ready I just print the various layers out and fold and tape the drill template to the box and go. When it is time to apply the graphic design, I return to the same document and print that out for my waterslide or etching. So far this has been very accurate, repeatable and keeps the entire design in one file minus the PCB layout.

VidSicious

#6
This ^^. I use a very similar method and it hasn't failed me yet. I use Pedal Vector Pack by "powerpopguy". The only real difference is that I don't really print out the side drill templates. I put everything together (like the hardware, PCB placement etc.) as if looking from the top, then put lines across where jacks and DC will be and once printed I simply use a ruler to get those side holes right.
You are also left with a canvas for your artwork. Convenient.

amptramp

The biggest problem with cast enclosures is the rounded edge that makes it difficult to determine where the edge starts.  It helps to take measurements across similar heights on the side to determine where the centre is then make all your measurements from the two centrelines.

I am glad I never had to use CAD programs for this sort of thing.  I find squared paper to be faster and less annoying.  And as R.G. said, you could use it as a centrepunching template.

thermionix

No printer.  I use blue masking tape on the enclosure, measure and mark with a combination square, and automatic center punch.  Drill, baby, drill.  T-handle reamer goes up to 1/2", breezes through diecast, comes in real handy.  Sometimes faster/easier than swapping bits.

amptramp

I use a centre punch followed by a step drill but to keep from doin it wrong, I measure the hole after each step.  So far, so good.

Rixen

to overcome the problem of measuring from rounded corners, place a couple of straight edges (short rulers, maxed out credit cards etc) against either side, and measure to those or the centre

Julian
www.rixenpedals.com

Gentle Jack Jones

I've been using a Photoshop template for artwork and drilling points as well. I downloaded it from one of these forums, and I'm grateful to whoever made it available. That said, it lacks (1) anyplace for the sides of the pedal, and (2) accurate sizes of the components inside the enclosure (it does have accurate sizes of knobs, etc., outside the enclosure). So, I'd be grateful if anybody who has more comprehensive templates for different size boxes (but primarily for 1590b) would upload and link to them from this thread.

Thanks in advance!

bluebunny

Quote from: Rixen on April 23, 2016, 11:44:55 PM
to overcome the problem of measuring from rounded corners, place a couple of straight edges (short rulers, maxed out credit cards etc) against either side, and measure to those or the centre

I use the same method, but I use the enclosure lid as my straight edge.  It's usually nearby...   ;)
  • SUPPORTER
Ohm's Law - much like Coles Law, but with less cabbage...

amptramp

#13
If you look at the drawing for the 1590BB, you have different dimensions for the opening at the lid end of the casting and at the top end.  They are 115 mm x 89.5 mm at the lid and 112.66 mm x 87.16 mm at the inner corners.  This is to provide the draft angle for withdrawing the housing from the mold, but it makes life difficult for someone trying to mark off the box for cutting holes.  It also means anything mounted on the sides actually points inward towards the lid.  If I were using Hammond boxes, I would put a piece of tape across the box from the lid edge around the top to the other lid edge and take the tape off and measure the length and mark the centre which is half the length.  Put the tape back on and the mark is your centreline regardless of the rounded edges.  Do that once in each dimension so you can get crossed centrelines for making accurate measurements.

In this case, the draft angle is 2.414 degrees.  (The difference of inner and end measurements is 2.34 mm.  The height is 27.75 mm.  Since we have the difference for both ends, one end is 1.17 mm.  1.17/27.75 is 0.0421621 and this corresponds to an angel of 2.414 degrees.)  This is enough to throw off measurements made by eyeballing the edge of the box.  Parts like jacks mounted on the side of the box will point down at this angle.

karbomusic

I just measured the box with a caliper and created my template(s) from that, that was the most accurate method once you realize which things to account for. Then create a paper template from that, all this 'what starts where' confusion is exactly why the paper template works so well. If you included some vertical and horizontal lines, including the frame boundary, it's almost impossible to not get everything centered and placed properly before drilling.