125B PedalPCB standard spacing?

[giovanni]

I made myself a little Inkscape template with all possible knob combinations that I can use as a starting point for my artwork (for laser cutting). I copied the template bits from a couple standard PedalPCB pdf templates to make sure I would get the spacing and hole size right. Here's an image of it:



Now here's my problem. I did a test cut of my Maleficent Mids faceplate and noticed a couple issues with the knob hole positions:

1. the top two knob holes are a bit too close to each other
2. the bottom knob is a bit too far from the top

Hopefully you can tell what I am talking about from the pics. Now, it's very possible that I messed up the drilling enough that the spacing of the knobs is noticeably off (although I had no issue getting the pedal in the enclosure; also I used Robert's excellent drill template), but it is also very possible that in copying the knob templates from the pdf to Inkscape some dimensions got messed up (wouldn't be the first time this happens). So I would like to double check my work by learning what the spacing between knobs is supposed to be.

I looked in this forum section to see if I could figure out the exact spacing between knobs in the standard PedalPCB templates but I haven't been able to. I guess maybe I could reverse engineer it from the Tayda templates but before going to that length, I thought I'd ask @Robert for help!

 

[giovanni]

One more pic:

 

[Robert]

The wider spacing (for 6 knobs) is 1.6" horizontally.

 

[Hal Harvey]

That looks beautiful

I use Inkscape too. I ‘print’ the drill page to PDF and then import that page into Inkscape. I leave all the import options default.

The PCB mounted pots have a bit of give, if you were to put a washer and nut on there, at least temporarily, would it pull it into the correct place?

 

[Robert]

Coincidentally I'm working on a commissioned job for a builder who uses laser cut faceplates...

They sent me the SVG that is used to cut the faceplates, but after using those exact coordinates to create a printable template the alignment is slightly off. Not enough to cause a problem, but just enough to be noticeable.

I measured my printed template with a caliper and it was dead on so I think there might be some very slight variations coming from the laser cutter. 1mm or less, but just enough that the outlines on the template don't perfectly match up like you'd expect.

 

[giovanni]

View attachment 70329


The wider spacing (for 6 knobs) is 1.6" horizontally.

So this picture is for the 4 knobs?

 

[giovanni]

Coincidentally I'm working on a commissioned job for a builder who uses laser cut faceplates...

They sent me the SVG that is used to cut the faceplates, but after using those exact coordinates to create a printable template the alignment is slightly off. Not enough to cause a problem, but just enough to be noticeable.

I measured my printed template with a caliper and it was dead on so I think there might be some very slight variations coming from the laser cutter. 1mm or less, but just enough that the outlines on the template don't perfectly match up like you'd expect.

Yeah I’m afraid there is some slight zooming going on in the laser software, but I want to cover all bases first.

 

[Robert]

So this picture is for the 4 knobs?

Yep.

 

[giovanni]

uhm I checked my Inkscape file and the horizontal distance is almost spot on 1.3" and the vertical spot on 1". So I think there may something off with the laser. I'm gonna have to run some tests.

 

[giovanni]

And in case you were wondering, in my plywood prototype those distances are just slightly too large. Like by maybe half a millimeter at most for the width. I'm gonna have to check the laser settings tomorrow. Glad I verified this, I felt like taking crazy pills.

 

[Robert]

Did you drill the enclosure yourself by hand, or is it a Tayda drilled enclosure?

Even if you mark the enclosure perfectly and use pilot holes the bit can sometimes wander enough to cause those variances.

Do you have an unpopulated PCB that you can lay the faceplate on to compare the measurements?

 

[giovanni]

Did you drill the enclosure yourself by hand, or is it a Tayda drilled enclosure?

Even if you mark the enclosure perfectly and use pilot holes the bit can sometimes wander enough to cause those variances.

Do you have an unpopulated PCB that you can lay the faceplate on to compare the measurements?

I did drill it myself yeah. I’ll test an unpopulated board too.

 

[Robert]

I never noticed how much my bit wandered until I tried to re-apply a paper template over a drilled enclosure to add a new hole.

 

[Giorfida]

Did you drill the enclosure yourself by hand, or is it a Tayda drilled enclosure?

Even if you mark the enclosure perfectly and use pilot holes the bit can sometimes wander enough to cause those variances.

Do you have an unpopulated PCB that you can lay the faceplate on to compare the measurements?

They can move quite a bit. Wishing I had access to a milling machine as holding spacing is a bit easier.
I’ve also found with the typical drill press, a heavy drill press vice to keep it the box from moving, coupled with center punch then center drill then use a good step bit will mitigate it.
So yea. I always get the Tayda predrilled wherever possible (even if it means having to add an extra hole sometimes)

 

[giovanni]

I’m gonna try printing my artwork on my printer to see if the prototype is indeed a bit bigger. I haven’t ruled out that problem with the laser yet. So it could be my drilling but I’m a bit doubtful. I haven’t measured the distances between holes yet though. One more thing to try.

 

[giovanni]

I think you guys are correct. My drilling was a bit off. I’m gonna try widening them holes and see if I can realign the knobs to the faceplate. I really need a drill press.

Edit: and yes the Tayda drilling service will be useful but I already have a ton of enclosures I ordered a while ago (ahem 2 years ago, in an aspirational bout of build planning) that I have to drill myself.