Mist or flood cooling

[T1DAVE]

I have cut and drilled all the holes on the chassis i made for my super without coolant and i had no problems

[Crawling Calvin]

Ok after goofing around a little here's what works best (for me). Lower the RPM to about say 80-100 and feed the drill bit in *REAL FAST* so it comes out in two "long slivers." Then back the drill out ASAP. Keeps the heat low... and its the best thing to do since I don't have a CNC lathe And I don't see the need for fancy parabolic drills... not yet tho

[Sydwaiz]

80-100? I tap at those speeds. Speed it up and feed it faster!

[Crawling Calvin]

Originally Posted by Sydwaiz

80-100? I tap at those speeds. Speed it up and feed it faster!

Or make a power feed on the tailstock I have one of the Harbor Freight Mini Lathes (not sure what size) and the wheel on the tailstock is mad tiny so feeding fast isn't easy! If I could go higher RPM I sure would, ive done it in my shop class and it works good

[Super]

A sharp bit and get those chips out of there. That's where most of your heat is coming from.

[Crawling Calvin]

Would something like http://www.mcmaster.com/#metalworkin...l-bits/=83x48l a "slow spiral" drill bit, which will get the chips out FAST be what I need

[Super]

A sharper bit angle helps too for soft material.

[Crawling Calvin]

Right, looks like all I can get is 118* but I can always grind it sharper if I need to. I just don't want to have any issues with the tip "grabbing" real hard. I have seen that happen before on CNC's with soft plastic, it starts to feed in, grabs, and jams it up (mind you that's like a half inch drill into UHMW soft materials.... with someone who didn't really know what they were doing!)

[Super]

I would do a lot of pecking once you got in deeper just to make sure the chips weren't wadding up in there.

[Crawling Calvin]

Originally Posted by Super

I would do a lot of pecking once you got in deeper just to make sure the chips weren't wadding up in there.

Makes sense to me I will see if I can't CNC these parts out, which is a lot faster, but time will tell Heck, they can run a ton faster than I can do it by hand

[tain4x4]

I don't even worry about coolant when drilling plastic at work. Unless your doing production you shouldn't worry either. A dab of wd-40 will keep it from melting when tapping. No need to spend the coin on a coolant system unless you plan on cutting metal.

[Crawling Calvin]

Update...
Running on a CNC sure helps #1 since it feeds so much faster and on and on... you get the idea The coolant flood not only helps with cooling the tools as well as preventing chip buildup. That said, i haven't done any deep hole drilling. For at home I figured out my main issue was:
The drill bit had a DULL tip, it was running a "tin outer coating and a black oxide inside" coating. I decided to go full TiN on the drill so well see how well that works out. As for tapping, my idea was to run some kind of substance over the tap mostly to flush the chips out as well as keep the heat down. That said, it isn't to complex to program a CNC to do that either right

[creepr69]

add a pecking motion to help drilling and add a stop fuction before tapping and manually add tap heavy in the drilled hole for tapping.