Lets talk DRILL BITS

With this stuff, sometimes the oil smokes a little if I try to press the bit through too fast, but the chips and curls come out OK and I haven't had any binding between the bits and the steel... the bits are staying sharp... that means it's working, right?

And yes, Nathan, the part about drilling then reaming is sinking into my brain... for my 1/4" holes, I drill a 1/8" pilot hole first, then re-drill to 1/4"... so i think I understand the concept.
 
For any precision hole,suck as pivot's/stop pins ect.you want to drill atleast 5 though undersize,then follow with a chucking reamer.not a drill.search for chucking reamers.
 
I'm a long way from that kind of precision, I just slap together fixed blades :D

But thanks for the info and keep the tips coming, guys!
 
You shouldn't be drilling and redrilling the same hole a bunch of times. Sometimes a pilot hole then drill, but you shouldn't be "reaming" with a drill bit. I guess it might be a better approach than nothing, but you should be reaming with reamers.

If you're using a pilot hole, it should be about the same diameter as the web on your next bit. So something like a 1/16" drill to be followed by 1/4".

When reaming, use moderate SFM. For your application the RPM should work out to something like 50 SFM which on 1/4" bit is something like 800 RPM. The feed is moderately high, something like .010" per rev for the sizes you'll be working in. The reamer should be feed back out of the hole at a similar rate it is fed in, don't just yank it out. This is a good application for oil.

The optimum order of operations is to spot drill (a center drill works), drill, bore, then ream. The spot drill is short and stiff and get the drill started in the right location. The drill removes the bulk of the material but the hole is not straight, round or smooth. Boring is a single point cutting operation that aligns the hole with the spindle and makes it straight and round, and you can probably skip this operation if you center drilled. The reaming operation follows whatever hole is there and makes it round, to size, and a good finish. If you really want to go nuts you can then grind or lap or burnish.
 
I've really enjoyed this thread. With the machining classes I've taken so far, I know just enough to follow along and feel all cool. You know, like when you take two years of Spanish and suddenly you can understand that the Hispanic guy in the grocery store wants to buy chicken. :D

But you shouldn't start trying to talk to him or you'll be saying something like the chicken is in the rake under the taco. :D

Thanks guys... :)
 
It will take me a couple reads to grasp that :o but I thank you for the information, Nathan.
Please continue to excuse my dumb questions! I love this place for the generosity of info shared, without making me feel like a total idiot.

I wish someone would ask a question about printing or guitars, so I could feel smart again... ;)
 
James_Terrio said:
It will take me a couple reads to grasp that :o but I thank you for the information, Nathan.
Please continue to excuse my dumb questions! I love this place for the generosity of info shared, without making me feel like a total idiot.

I wish someone would ask a question about printing or guitars, so I could feel smart again... ;)
Click to expand...


Dear James,

I'm trying to print a picture of a flaming drill bit onto my guitar using a cutting oil. I'm having a problem with the image just running and making an oily mess, and it sounds like all the goo is muteing the tone. Should I be using something other than oil base here?
 
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