Author Topic: Oh, Snap!... A drill that is... (Read 1607 times)

LittleBigBoom · « **on:** April 01, 2010, 07:55:54 PM »

Well here it is! Almost done with the barrel!

However,,, I have a small problem... One that for most of you guys is probably very small but for a beginner like myself...

Well,,,,,,, as I was drilling the touch hole the bit broke.

I was spinning it fast and feeding it very slow, but I guess not slow enough.

Now on the bright side I can "hear" that the touch hole is connected if I tap on it, but I can not drive it through with a small punch due to the bur that is still there... I can see a bump at the exact spot in the barrel where I wanted the hole. I picked at it and it is the drill-bit-end and bur, but I cant get at it to grind it because it is at the bottom of the bore, and the bit being the hardest metal on the face of the planet and most of this galaxy,,, I can't drill it either...

My Family who thinks my cannon are "cute"

thinks I should load and fire it using electric ignition down the muzzle and see if the bit blows out. And although this sound interesting, well, um, I don't know if that would be a good Idea...

The bore is .50 inch.

What would be the best way to get the bit out? any thoughts?

GGaskill · « **Reply #1 on:** April 01, 2010, 08:42:47 PM »

It is certainly worth a try to blow it out with a blank charge fired from the other end; if you do try this, make sure the flying drill bit goes somewhere that won't cause damage or injury. The barrel will recoil so be prepared to deal with that also.

If that doesn't work, or you don't want to try it, try putting your half inch drill bit in the hole backwards and tap on the point to see it you can dislodge the broken bit. You may be able to force it out the hole the other way.

If these two ideas don't work, look in the Yellow Pages for "Tap disintegration" or "tap disintegrators" and take it to them.

1Southpaw · « **Reply #2 on:** April 02, 2010, 04:20:12 AM »

If I read this correct , The bit broke just as it was breaking through to the bore ?
Your bore is 1/2" how long is the broken piece ?
If it is less than 1/2" perhaps a punch the same size as the touch hole could drive it in to the chamber .
Have the barrel clamped solid on a solid base and tap lightly , inspecting the bore to see if it budges .
If so just maybe the broke bit can be driven through and in to the bore .
Or as George mentioned . A round rod the dame diameter as bore may push the buldge back up loosening the bit . Worth a try , Shame to get this far and stall out !

Zulu · « **Reply #3 on:** April 02, 2010, 04:53:08 AM »

It's ruined. Start another one and send that one to me for disposal.

Zulu

armorer77 · « **Reply #4 on:** April 02, 2010, 05:40:42 AM »

If you can lock it down in a mill , a straight flute carbide drill will drill through the broken drill bit . I have drilled out numerous broken taps this way . Armorer77

LittleBigBoom · « **Reply #5 on:** April 02, 2010, 01:23:55 PM »

It LIVES!!!!!

I tried all the suggestions posted (and non of them worked but that is beside the point...) but ended up just "corking" up the one hole and carefully drilling another hole on the other side... I guess I could call it a dual touch hole cannon for better ignition...

But that would mean both would have to work...

So after painting tonight I will post fire and smoke tomorrow.

LBB.

Zulu · « **Reply #6 on:** April 02, 2010, 01:27:48 PM »

What did you "cork" it with? I'm not liking the sound of this.
Zulu

I'm not being critical. Just concerned.
What did you do with the "dimple" on the inside of the bore?

GGaskill · « **Reply #7 on:** April 02, 2010, 01:49:05 PM »

If there is any connection to the flutes of the broken drill, you will have a place that will trap combustion products and cause corrosion, and maybe trap still burning remnants that would cause a premature ignition which is dangerous.

Zulu · « **Reply #8 on:** April 02, 2010, 01:57:02 PM »

GGaskill,
In addition to everything you said, until we know how he "corked" it, we don't know if that piece of drill bit will be a projectile or not.
Zulu

LittleBigBoom · « **Reply #9 on:** April 02, 2010, 02:45:39 PM »

"corked" = welded solidly in place. which I should have said in the beginning... it would have made so much more sense... Oh bother.

"If there is any connection to the flutes of the broken drill, you will have a place that will trap combustion products and cause corrosion, and maybe trap still burning remnants that would cause a premature ignition which is dangerous."

I am NOT going to shoot this one after the initial smoke and fire shots and after I get the carriage done, due to that very issue. But it had to work once so It was a real cannon,,, that worked at one point in time... But it is more for gratification that after all that work I put in to it, and not to have it fire once...

As for that dimple I did get it drilled away. And after it was gone I tried these following ideas.

Hydraulics, after filling the bore with oil and using a rod that fit perfectly into the muzzle and using a little hydraulic force to try and push the bit out, it resulted in nothing but about a drop of weeped oil out of the touch hole.

Also trying to drive the bit all the way through did nothing.

Also blowing it out with black powder didn't work, So I gave up and welded it in.

So sorry Zulu, you are not getting this one...

LBB

Double D · « **Reply #10 on:** April 02, 2010, 03:11:28 PM »

Welded? Not good! Welding sets up the same circumstances that cause me to warn against seemed tube liners.

The correct way to fix this would have been to dril out the hole to the next larger size and sleeve the hole.

KABAR2 · « **Reply #11 on:** April 02, 2010, 03:26:25 PM »

Quote from: LittleBigBoom on April 02, 2010, 02:45:39 PM

"corked" = welded solidly in place. which I should have said in the beginning... it would have made so much more sense... Oh bother.

I am NOT going to shoot this one after the initial smoke and fire shots and after I get the carriage done, due to that very issue. But it had to work once so It was a real cannon,,, that worked at one point in time... But it is more for gratification that after all that work I put in to it, and not to have it fire once...

LBB

LLB,

Here is the only problem I see........ In a 100 or so years when you are dust your creation will live on.......... what happens when some
relative or other unknowing person tries to light this off? after all it is a cannon with a touch hole.........

Double D · « **Reply #12 on:** April 02, 2010, 03:37:45 PM »

And there is nothing wrong with shooting it now if you fix it right, and you can still do that!!!

Cat Whisperer · « **Reply #13 on:** April 02, 2010, 04:05:13 PM »

I would be inclined at this point to put it in the mill and carefully, slowly work through several carbide bits and cut a 1/4 or 3/8 hole right through the drill bit and the weld. It usually consumes the carbide end mills a little at a time, but they do work. Then I'd put in a liner of copper with the correct diameter fuse hole.

Cannoneer · « **Reply #14 on:** April 03, 2010, 04:21:13 AM »

LittleBigBoom,
Since you already have the second vent drilled, you could follow the advice (just leave out the part about drilling the vent through this bouche) about drilling a larger hole through the weld and broken bit, and tapping the hole to accept a steel bolt with the head sawn off, then weld it in place. This would make your barrel safe to fire.
I've got a small stainless barrel with a .50 cal. bore that is nicely machined, but whoever drilled the vent made it 5/32", and on top of its being to large, he also didn't place it on the line of metal down the center of the top of the tube, its off to one side; so I'm going to drill a larger centered hole and install a copper bouche.

dirtdobber1919a4 · « **Reply #15 on:** April 03, 2010, 11:47:14 AM »

another idea for future reference would be a left handed drill bit. sometimes works for me.

LittleBigBoom · « **Reply #16 on:** April 04, 2010, 07:36:30 AM »

I've been ordering some tools. The cannon got the better of me, it is too nice to let it go non fireable.

I like the ideas of Cw and boom j. Is the bolt idea O.K. DD?

A left handed drill? had never heard of that.

LBB.

Cat Whisperer · « **Reply #17 on:** April 04, 2010, 08:21:05 AM »

they also make left-handed reamers.

Double D · « **Reply #18 on:** April 04, 2010, 08:24:51 AM »

Bolt is absolutely okay, that basically all a vent liner is. That is how they repair eroded vents orignally. some guns even had two vents, one plugged with zinc until needed.

GGaskill · « **Reply #19 on:** April 04, 2010, 08:26:57 AM »

If you drill out the broken drill and replace it with a bolt, it would be a good idea to soft solder the bolt in place (tin the threads in the hole and on the bolt, then heat both to the melting point of the solder and screw together.) Then run the half inch drill down the bore again to clean up any part of the bolt that sticks into the bore.

You don't want any gaps where a spark could hide.

irishman · « **Reply #20 on:** April 10, 2010, 10:55:04 AM »

Id like to comment on one possile cause, that may help someone avoid the agony of what you are going thru.

The flutes in the drill may have been loaded with material, causing undue resistance, most critical at "breakthru." One can usually feel the resistance in the feed, but, it is prudent to pull it out and let it clean out the flutes.

Michael

KABAR2 · « **Reply #21 on:** April 10, 2010, 11:34:38 AM »

Ummm..... With a left handed drill wouldn't you have to run in reverse?
some people don't have milling machines and drill presses I have seen run in one direction.......

dan610324 · « **Reply #22 on:** April 10, 2010, 01:38:45 PM »

a good drill press must go in both directions
how else to make threads in them

GGaskill · « **Reply #23 on:** April 10, 2010, 02:59:36 PM »

a good drill press must go in both directions. how else to make threads in them

The tapping heads I have seen for use in a drill press have internal gearing and clutches such that the tap rotates right handed on the down feed and left handed on the up feed. The drill press spindle always rotates one direction.

dan610324 · « **Reply #24 on:** April 10, 2010, 03:11:39 PM »

well not mine
my head just got some kind of clutch thats adjustable
so I need to reverse the drill press

GGaskill · « **Reply #25 on:** April 10, 2010, 04:04:33 PM »

my head just got some kind of clutch thats adjustable

Sounds like a fancier drill press than is common over here.

dan610324 · « **Reply #26 on:** April 10, 2010, 04:09:07 PM »

I guess its 40-50 years old
swedish manufacturer , Arboga

LittleBigBoom · « **Reply #27 on:** April 13, 2010, 03:43:05 PM »

Here goes,,,

I did some searching and found a lot of old topics on this board about this same problem... Isn't that odd...

so this thread is just another in a long line... sorry...

I bought a super carbide mill and started milling away. That mill bit is neat! Straight through that broken bit like it wasn't there... I also found that the diamond dremel bits are really good too.

Then after the last of the old bit was removed, I went to tap thread,,, and snap! The tap broke... But I have more luck with those, so after I got it out my Dad helped with the soldering and Badaboom! It is fixed!

I test fired it and it works great!

Thanks guys for putting up with my rail to rail personality...

Cat Whisperer · « **Reply #28 on:** April 13, 2010, 04:36:17 PM »

Ahhhh carbide! (and diamond).

Any pix? (I would guess not.)

THANKS for the report! It now adds to our collection of "here's how I DID it" not just "here's how I THINK it can be done".

We sent out LOTS of dies (brake pad manufacturing) over the years, and the shop that did the work would often run through several carbide bits going through the hardened tooling. Much easier on just drill bits.

RocklockI · « **Reply #29 on:** April 13, 2010, 05:16:32 PM »

Do you now have two vent holes 180 degrees away from each other ?

Gary