Stepped Bit / Progressive Bit

Finished my Face Melter build (first build ever) and on first boot up, it worked! Great feeling. This pedal sounds K I L L E R, by the way!

What is the appropriate size "stepped" drill bit needed for enclosure holes? I have a 3mm I will use just for LED openings but I had to keep going up in bits to make the holes for my pots, my power input, my switch button, the output jacks, etc. I ended up doing 1/2" for the switch button which is the largest opening on this specific box. Would a stepped bit that does 1/8" up to 1/2" be sufficient for basically all pedal needs? Does anything ever require a 3/4" or 7/8" sized opening?

THANKS!

OOPS - I should have put this in THE TOOLBOX section! Can this get moved?
 
Stepped-bits have their place in my drilling arsenal, but so do regular bits. I've got a blend of metric and imperial sizes, which has come in handy for odd-sized switches, bezels etc...

For instance, if you're drilling 1590A jack-holes, you do NOT want a stepped bit. Before I had my bit collection, I had the one stepped bit and it chewed up the opposite wall of the 1590A — luckily it didn't go all the way through, which leads me to...

One of the best purchases I've made is a quality reamer:

c12672d2a93818dcfb3336f90faea200.jpg



Great for cleaning up holes or hogging something out beyond or between bit sizes you have...

Mine sees less duty now that my bit collection has expanded.
 
Stepped-bits have their place in my drilling arsenal, but so do regular bits. I've got a blend of metric and imperial sizes, which has come in handy for odd-sized switches, bezels etc...

For instance, if you're drilling 1590A jack-holes, you do NOT want a stepped bit. Before I had my bit collection, I had the one stepped bit and it chewed up the opposite wall of the 1590A — luckily it didn't go all the way through, which leads me to...

One of the best purchases I've made is a quality reamer:

c12672d2a93818dcfb3336f90faea200.jpg



Great for cleaning up holes or hogging something out beyond or between bit sizes you have...

Mine sees less duty now that my bit collection has expanded.
I find that for 1590A enclosures, all that’s necessary is a stepped bit that has larger step increments. I use the set pictured below, and just use the wider step bit for 1590a enclosures since the 3/8” step is closer to the tip than on the more gradual bit.
 

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Off the top of my head I think you can get away with the 1/8-1/2“step bit. But if you ever do an illuminated foot switch I believe that hole is 5/8” my advise is get a nice bit, don’t cheap out... a good one will stay sharp forever if you are kind to it... sharp bits= cleaner holes and less effort. A dull bit can also cause you to drift more and your holes might not end up Exactly where you would like them.
 
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Anybody here using a cutting-oil with their drilling?

That'll help prolong the life of your bits, but the downside is getting ALL the oil off the enclosure for painting/finishing (I'd rather do that than risk mucking up the paint and artwork [what artwork?] by drilling last...).

I've got some low viscosity bike-chain lube for home, gave my friend a proper bottle of cutting oil for his atelier's drill press.
 
Cutting oil isn’t necessary for what we are doing...( unless you are doing some crazy machining.) but it doesn’t hurt. For clean up though I always do a pass with Iso, then soap and water and do a proper water break test. I started doing that after I had been having a few adhesion issues with decals... now they stick all the time!
 
Here's my notes on drilling sizes. My step drill bit goes from 1/4 in to 3/4 so it covers all the required sizes. Per your question, nothing requires over 1/2, but I think the 1/4-3/4 is a commonly found stepper size.

Drilling hole sizes:​

footswitch: 1/2 (12.7mm)
pots: 5/16 (7.9mm)
5mm led bezel: led bezel: 5/16
5mm plastic bezel: 1/4
3mm led bezel: 1/4
mini switches: 1/4 (6.35 mm)
jacks: 3/8 (9.5mm). The Lumberg and asian ones measure 8.7 and switchcraft measure 9.2 with calipers
switched dc jack: 7/16 - 1/2 (note it's slightly above 7/16 so need to drill then enlarge until it fits) (11.1-12.7 must be 12 mm)
low profile dc jack: 5/16
 
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Can someone remind me what the mounting hole diameter is for the large Lumberg DC jacks, please? I can't find my notes 😅
 
I've used a big box step drill that goes up to 1/2" for years and many hundreds of holes. It's worked very well and the only issues have been user error. Inspecting it, it's got a decent amount of aluminum stuck to it, but it keeps on cutting like a champ.

I bought a Harbor Freight larger set for amp projects and hope they work as well. At least I hope they last until these three amp projects are done anyway.
 
I have a few titanium bits and step bits. I usually start with a hole puncher, then proceed with 1-2 of the smaller bits (smaller than the smallest step bit size), then I switch to the step bit with the most gradual increments and I just drill until the hole is the correct size (I just test with the part that needs to fit in it). I have definitely made a couple mistakes in the past but nothing too serious. Also I wrap the enclosure on painter tape to protect the finish.
 
I find that for 1590A enclosures, all that’s necessary is a stepped bit that has larger step increments. I use the set pictured below, and just use the wider step bit for 1590a enclosures since the 3/8” step is closer to the tip than on the more gradual bit.
I use a similar kit. Really all you need is the 3/32" bit and the skinnier step bit. I use a 3/32" for pilot holes and then use the skinnier step bit for most of my holes. The larger step bit is useful for those times when larger holes are needed. Otherwise, for most applications, the skinnier one will suffice.
 
I use a similar kit. Really all you need is the 3/32" bit and the skinnier step bit. I use a 3/32" for pilot holes and then use the skinnier step bit for most of my holes. The larger step bit is useful for those times when larger holes are needed. Otherwise, for most applications, the skinnier one will suffice.
100%

I only use the big step bit if the small one will drill thru the other side of the enclosure (for example, 3/8" holes for jacks on a 1590A-- the skinny step bit would pop through the other side) or if I'm drilling an exceptionally large hole.
 
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