Hand drilling large holes (experiments)

[machine1medic]

I've been back in maint, repair, & weighting, for several years now.
Now & then one needs a clearence hole for a serious cleavice, to rig from. Can't always blow thru with A/O or plasma.
I've tried many ways to do this. I even watched vids of farmers using the famous Cole Drill a few years ago. NOTE: I learned allot from that.
Last week I needed (5) 13/16" diameter holes thru 3/8" 304 stainless.
So I tried a few tweaks. Pretty happy with the results. No cheating. Took about all the elbow grease I could muster.

 

[DDoug]

I've been back in maint, repair, & weighting, for several years now.
Now & then one needs a clearence hole for a serious cleavice, to rig from. Can't always blow thru with A/O or plasma.
I've tried many ways to do this. I even watched vids of farmers using the famous Cole Drill a few years ago. NOTE: I learned allot from that.
Last week I needed (5) 13/16" diameter holes thru 3/8" 304 stainless.
So I tried a few tweaks. Pretty happy with the results. No cheating. Took about all the elbow grease I could muster.

What are you trying to show us here ?

 

[rons]

Last week I needed (5) 13/16" diameter holes thru 3/8" 304 stainless.
So I tried a few tweaks. Pretty happy with the results. No cheating. Took about all the elbow grease I could muster.

With a hand drill and piece not clamped down the hole has three lobes.

I can see a good use for this if you are drilling holes on the go.

https://www.grainger.com/product/40LJ21?gucid=N:N:PS:Paid:GGL:CSM-2295:4P7A1P:20501231&gclid=EAIaIQobChMI_866iq36_gIVI31MCh1gEwNiEAQYASABEgLxg_D_BwE&gclsrc=aw.ds

 

[memphisjed]

Try hole saws, a little cordless drill can pop a 13/16 without to much elbow grease- lots of forearm torque

 

[machine1medic]

Yeah I like holesaws. Using drill bits is a study for me. So when I can control factors, I do. Decades of needing holes NOW, with what ever you have. Underneath the work. Up on ladders.
Reaching over the bucket on a boom lift. Shaping the drill geometry. Dry or cutting fluid. Etc etc.

This time... better drill tip geometry and drilling dry.

Off to work

 

[Gordon Heaton]

I can see a good use for this . . .

A mag drill isn't much good when he's drilling 304.

 

[Gordon Heaton]

You can use annular cutters with a hand drill in a pinch if you make an adapter. I've done it 'out of position' on an I-beam and got good results. Less pressure required than a standard hole saw, a better hole too. Downside is that you really need to hold it steady and straight to avoid binding or breaking the cutter. Having a helper there to lube the cut is also good.

 

[rons]

A mag drill isn't much good when he's drilling 304.

Hougen HMD904SC Magnetic Drill w/ Swivel Base & Coolant - 09

www.mrmtool.com

The link is an example only.

I would chuck a milling cutter and run at 300 - 400 rpm.

 

[SteveEx30]

Try hole saws, a little cordless drill can pop a 13/16 without to much elbow grease- lots of forearm torque

Thru 3/8" stainless I think your going to need a decent amount of elbow grease..


Just curious you have no Drill press ? Be much easier then by hand

 

[eKretz]

Sometimes you don't have a choice. I've had to hand drill larger holes through thicker stuff at times too. The drill geometry is everything if you don't want to wear yourself right the *f* out. What did you alter on the drill geometry to get it where you liked it M3M?

 

[boslab]

Go get a rotobroach, or if stuck hand job, get someone else to hold the thing esp when it breaks through and snatches!, my wrist can’t do it anymore.
Mark

 

[machine1medic]

Drill press is trapped in a corner. And our press is against a wall. Laurel and Hardy must have layer out this shop. Part is 12 feet long.
Many have come up with great drill point configurations. I have several. This one I hoped would be good with no predrilling. It worked but took too long. So I predrilled 7/32.

I'll attempt a few pics.

 

[machine1medic]

Go get a rotobroach, or if stuck hand job, get someone else to hold the thing esp when it breaks through and snatches!, my wrist can’t do it anymore.
Mark

I back up the part with tough endgrain hardwood when possible.
Hole (5) just about nailed me anyway.

 

[L Vanice]

"Hand drilling large holes (experiments)"​

When I read the title, I thought of a couple of the largest antique hand-forged drill bits in my collection. They were meant for actual hand drilling in iron and steel, none of that sparky cheating. Think fat wooden stick with a square hole chiseled through the center powered by a strong apprentice. Or, if modern designs were available, a forged crank like the old carpenter brace and a happier apprentice.

Larry

 

[plastikdreams]

What are you trying to show us here ?

What are you trying to show us?

2 words...

Thin ice

 

[Farmer Phil]

A mag drill isn't much good when he's drilling 304.

Not completely accurate. I clamp steel plate to many non-ferrous materials which to attach a mag drill to.

 

[guythatbrews]

It's tough to hand drill stuff like that.

I don't use the little button that holds the drill trigger on any more. I was drilling a big hole and the drill grabbed. The drill motor got away from me cause the trigger was locked down and smacked my pinky finger right on the end. It broke my middle finger bone in six pieces lengthwise. They wired me back together and it's not too bad but I don't recommend it.

Be careful of those big drills.

 

[gtermini]

I got sick of breaking my back lugging the big milwaukee mag drill around to drill a 3/8 hole here and there and bought one of the little magbore magnetic drill stands with a 1/2" holeshooter drill. The thing is handier than shirt pocket. You can hold it in place with one hand to get it set. It'll punch a 1-1/2"+ hole easily with one of the "carbide holecutter" style saw sold now. The only thing I don't love is you have to run the trigger yourself while you drill.

 

[john.k]

You want to try some of the big old IR air drills .....Ive got hand IR drills up to #5 morse.......another of the olden days methods was the ratchet drill ,held down with a chain ,or a angle piece ......these drills could drill 2" holes in a thick boiler shell really quickly .

 

[gusmadison]

+2 on the Magbore! Great piece of kit and well made in my opinion.
Like any tool one acquires, you just think different when you own one and are tasked with jobs you might have formerly turned your nose up at.