Metric Step Bit Recommendations?

Bricksnbeatles

Member known well
Does anyone have suggestions for a good Metric step drill bit that goes up in 1mm increments? It’s hard enough to find a metric step bit in general, but those few which I have found all appear to be really cheap crap. I use a nice Milwaukee step bit set that my uncle gave me because he got it for a job once and never used it again— unfortunately looks like Milwaukee is in the infuriating “SAE only” camp in the US, and most of the dealers who do sell their metric step bits don’t ship to the US. Those who do, it’s 3x the cost, or more, of a comparable SAE Milwaukee bit.

Anyone have any favorites?
 

Cucurbitam0schata

Well-known member
I have the DeWalt SAE bit that goes to 1/2" (12.7mm) - works fine enough for my builds. Here's an Bezos link, and you can get them easy at your hardware store, too.

Additionally, I use a center punch to make sure my holes are dead on. Works pretty well for me.
 

Harry Klippton

Well-known member
I stopped using a cutting oil when I started using no film decals cuz I put the decals on and then drill. My main complaint with that bit is that it seems a little soft and it clogs up easily. I'm mostly satisfied with the results I get from it but it seems like a shitty tool. I like things that will last forever
 

finebyfine

Well-known member
I get the impulse. If there's consensus here I'd love to try a better one.

Family friend who taught showed me my way around tools always used to say "it's better the drill bit break than the thing you're drilling."
 

peccary

Well-known member
I stopped using a cutting oil when I started using no film decals cuz I put the decals on and then drill. My main complaint with that bit is that it seems a little soft and it clogs up easily. I'm mostly satisfied with the results I get from it but it seems like a shitty tool. I like things that will last forever
I've used three different brand step-bits and they always get gummed up for me. I keep a little nail net to the press to clean it out before starting a new hole. I think it's just the soft nature of aluminum. I also just use SAE because with every hole being plugged with some kind of jack or pot I don't mind it being slightly larger. And, you know, something about space ships.
 

Stickman393

Well-known member
I like the spiral cheapies on Amazon.

Aluminum is sticky, and it will form a film on the bit pretty quickly. Over time , that can build up and dull the bit. Coating helps, but lube will prolong the life of the bit...I tend to use some non-toxic stuff specifically for aluminum.

If accuracy is a concern...say the bit starts drifting a little bit, it could be a few things going wrong. Best to use high speed with something soft like aluminum, use a...eh..."natural" cutting speed. Let the bit do the work, father than the downward force.

Something I do when I want like...perfect accuracy: map your holes, center punch with an optical center punch. Use an XY table and a wiggler to find the indentation, then use a center-finding bit of the same diameter as your first step to drill the target. Pull the center finding bit, and step drill to the proper size.

Which is A LOT of work for each hole. Honestly I only go through this process if I know that I have a really tight build...

Nowadays I'm much happier to just let my CNC machine do the work. That is, when I don't have it in pieces.

...sigh...one of these days I'm gonna have to bite the bullet and just buy better machine...
 

vigilante398

Authorized Vendor
Nowadays I'm much happier to just let my CNC machine do the work. That is, when I don't have it in pieces.

...sigh...one of these days I'm gonna have to bite the bullet and just buy better machine...
It's totally worth it, I promise ;) I had a cheap CNC for 6 years and finally upgraded last year, completely changed my life.
 

Stickman393

Well-known member
It's totally worth it, I promise ;) I had a cheap CNC for 6 years and finally upgraded last year, completely changed my life.
Ohhhh, what'd ya get? I'm considering a conversion kit for my x2-style mini mill...but it's a lot of scratch for something that would be great for small aluminum projects, passable for steel, but would be super limited in terms of working area.
 

vigilante398

Authorized Vendor
Ohhhh, what'd ya get? I'm considering a conversion kit for my x2-style mini mill...but it's a lot of scratch for something that would be great for small aluminum projects, passable for steel, but would be super limited in terms of working area.
I wanted to be able to do bigger stuff, I moved up to a Chinese "6040" machine. Between the machine and the spindle controller I think it was around $900, which is a lot more than my old machine but a lot less than I expected for something that size. Big enough for guitar bodies, not quite big enough for a neck though.
 
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