Issues Drilling Tang Holes

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CujiWuji

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I tried searching for another post covering my question but didn't find anything that fit exactly. If there is one please let me know and I can remove my post. Now on to my question:

I am running into issues with drilling my tang holes in a couple fixed blade knives. I am using 1095 steel (unhardened) and am trying to drill 5/32 holes for my pins. I picked up a cheapo HF Drill press a little while back and have been trying to use that. I have it on the lowest speed setting which is something along the lines of 780rpm and have a couple different 5/32 bits that i had picked up. For some reason the hole will start out fine, but then about 1/4 to 1/2 way through it just stops and the bit spins without cutting. I don't exactly have any cutting oil at the moment (just haven't had the time to pick any up yet) but have been using some 80w-90 gear oil i had sitting around, could that be what is causing issues, or is it something else entirely like drill speed or bit type?

If anyone could point me in the right direction I would eternally grateful!

Thanks in advance,

-Cuji
 
Yep, I buy 10-packs in common sizes on Amazon. I drilled at least 100 3/16" holes in one sitting without coolant without wearing out the bit.
The ones I got aren't available, but if you search "1/8 cobalt M42" you will find similar. I notice that a lot of cheaper m35 are for sale. I haven't tried those.
 
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Drilling at appropriate speeds & feeds is necessary for satisfactory performance regardless of bit you use. You can do a simple Google search for "drill speed chart" or something similar to download or refer to for the materials you are drilling.
 
Wow, ok well in that case it does sound like i need some different bits. Appreciate the info! Same to you Buhlmann, i'll have to take a look at the speed chart, though i don't think i can go any lower than 780 on this drill press, only faster.
 
I don't have charts in my head, but I think you 5/32 (4 mm) needs to spin faster. Quality sharp HSS bits are a must.

Finally you will reach the maximum of what your cheapo HF drill press will handle. From my experience with cheapo drill presses it will be about 8-10 mm holes in 6-10 mm steel, they will bind, shudder, creak and just be a pain to drill.

But bits up to 6 mm in steel up to 6 mm should me manageable with right speed and right bits.
 
I use liquid dish soap at home as a lube for drilling holes.
I also work around my chuck when tightening it with key.
Or use hex shank
If drilling larger holes. Drill a pilot.I
Center punch
Prevent work from sucking up and spinning.
Clamp work down, or use a backer board.
Let up the pressure as your bit starts to break through
No gloves.
 
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FredyCro said:
I don't have charts in my head, but I think you 5/32 (4 mm) needs to spin faster. Quality sharp HSS bits are a must.

Finally you will reach the maximum of what your cheapo HF drill press will handle. From my experience with cheapo drill presses it will be about 8-10 mm holes in 6-10 mm steel, they will bind, shudder, creak and just be a pain to drill.

But bits up to 6 mm in steel up to 6 mm should me manageable with right speed and right bits.
Click to expand...
I never would have thought faster could be something i was missing! Everything i've read so far was saying to use the slowest speed possible. I'll definitely give it a shot along with some of the other tips in here.
 
Crag the Brewer said:
I use liquid dish soap at home as a lube for drilling holes.
I also work around my chuck when tightening it with key.
Or use hex shank
If drilling larger holes. Drill a pilot.I
Center punch
Prevent work from sucking up and spinning.
Clamp work down, or use a backer board.
Let up the pressure as your bit starts to break through
No gloves.
Click to expand...
All fantastic info! Dish soap is not one i have heard of before, but definitely worth giving it a shot for sure since i've always got some on hand. Thanks!
 
CujiWuji said:
I never would have thought faster could be something i was missing! Everything i've read so far was saying to use the slowest speed possible. I'll definitely give it a shot along with some of the other tips in here.
Click to expand...
For tool steel use the following formula for RPM

50 surface feet per minute (SFPM) times 3.82 (constant value) divided by tool diameter.

So 191 divided by .156 = 1224 RPM

Plus —> quality drills like cobalt HSS.
 
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