Author Topic: Nano-mortar  (Read 41134 times)

0 Members and 3 Guests are viewing this topic.

Offline seacoastartillery

  • GBO Sponsor
  • Trade Count: (1)
  • Senior Member
  • *****
  • Posts: 2853
  • Gender: Male
    • seacoastartillery.com
Re: Nano-mortar
« Reply #60 on: February 15, 2008, 05:34:58 AM »
Everyone:

  Please use authentic black powder in ALL Cannon.  To make common 1F or 2F smaller, say 5F size, just use an old spoon to crush a PINCH of your larger grain BP on a sheet of notebook paper.  Fold the paper in half to make a trough and trickle the fine powder into the mini bore.

     So what type of black powder, nano-cannon or nano-mortar are you considering?

Regards,

Tracy and Mike

Smokin' my pipe on the mountings, sniffin' the mornin'-cool,
I walks in my old brown gaiters along o' my old brown mule,
With seventy gunners be'ind me, an' never a beggar forgets
It's only the pick of the Army that handles the dear little pets - 'Tss! 'Tss!

From the poem  Screw-Guns  by Rudyard Kipling

Offline lance

  • Trade Count: (0)
  • Senior Member
  • *****
  • Posts: 1249
  • Gender: Male
Re: Nano-mortar
« Reply #61 on: February 15, 2008, 03:01:54 PM »
 I'll try something saturday afternoon,don't feel like going out in the cold shop tonight. Right now, i'm thinking .177 pellets or BB's are way too big for a nano-project. Got some .22 Rat Shot shells, loaded with #12 shot, i'll cut one open and experiment...........
PALADIN had a gun.....I have guns, mortars, and cannons!

Offline lance

  • Trade Count: (0)
  • Senior Member
  • *****
  • Posts: 1249
  • Gender: Male
Re: Nano-mortar
« Reply #62 on: February 16, 2008, 08:58:39 AM »
O.K.it's saturday afternoon and here's what i came up with. In this picture are some scattered #12 shot from the busted open .22 Rat Shot Shell, also a few BB'S and a couple of .177 pellets for size comparison. Also the head of the nail that i cut the barrel out of. This is neither a cannon or mortar,but it's a tooth pick for a tiller Hand Gonne that shoots #12 lead shot!......I crushed some FFFg Goex for this very small bore,and stood about 3 feet away from the side of the shop and did hear the very small pellet hit the wall. Tim will have to come over and help with smoke and fire pictures,cause i had my hands full with this beast...............Double click on the pic and you can zoom it.
PALADIN had a gun.....I have guns, mortars, and cannons!

Offline seacoastartillery

  • GBO Sponsor
  • Trade Count: (1)
  • Senior Member
  • *****
  • Posts: 2853
  • Gender: Male
    • seacoastartillery.com
Re: Nano-mortar
« Reply #63 on: February 16, 2008, 09:38:07 AM »
     Lance,

You proved beyond any doubt that imagination is just as important as a shop full of expensive machinery!!  We like it!  It will be quite a challenge for someone to come up with a smaller bore  than your gonne has.  We will probably get a chance to start on our 1/56th scale 10" Rodman Gun this afternoon.

Good show!

Mike and Tracy
Smokin' my pipe on the mountings, sniffin' the mornin'-cool,
I walks in my old brown gaiters along o' my old brown mule,
With seventy gunners be'ind me, an' never a beggar forgets
It's only the pick of the Army that handles the dear little pets - 'Tss! 'Tss!

From the poem  Screw-Guns  by Rudyard Kipling

Offline rifleshooter2

  • Trade Count: (0)
  • Avid Poster
  • **
  • Posts: 212
Re: Nano-mortar
« Reply #64 on: February 16, 2008, 12:46:40 PM »
Wow Lance that's too cool. I take my hat off to you.

Andy
Save Legionville

Offline intoodeep

  • GBO Supporter
  • Trade Count: (5)
  • A Real Regular
  • *****
  • Posts: 776
Re: Nano-mortar
« Reply #65 on: February 16, 2008, 01:36:47 PM »
 Gee Whiz, Lance. That's one dangerous tooth pick you got there....:D  Kinda, James Bond like.;) Just be-careful which end you put in your mouth....;D

 All joking aside. Nice Job & Great idea!!!!

 

     
If you make it idiot proof, then, someone will make a better idiot.


Offline Terry C.

  • Trade Count: (0)
  • Senior Member
  • *****
  • Posts: 1215
  • Gender: Male
  • I see what you did there...
Re: Nano-mortar
« Reply #66 on: February 16, 2008, 01:51:21 PM »
Lance, I think this surpasses the realm of nano-artillery.

This is a pico-gonne!

Offline MikeR C

  • Trade Count: (0)
  • Avid Poster
  • **
  • Posts: 178
  • Gender: Male
Re: Nano-mortar
« Reply #67 on: February 16, 2008, 02:52:12 PM »
So, Lance, did you sub bore the chamber?  :)

Offline seacoastartillery

  • GBO Sponsor
  • Trade Count: (1)
  • Senior Member
  • *****
  • Posts: 2853
  • Gender: Male
    • seacoastartillery.com
Re: Nano-mortar
« Reply #68 on: February 16, 2008, 03:41:22 PM »
     Lance,    What bore size are you using to throw these bone crushing .050" pellets?  Have you allowed a full 1/40th for windage to avoid the tremendous increase in pressure that a tight bore in this ominous size can create?  ;) ;) ;) ;) ;) ;) ;) ;) ;) ;) ;) ;)

You are WAY ahead of us; we just barely found a good picture to go by.  Maybe tomorrow? 

Tracy and Mike
Smokin' my pipe on the mountings, sniffin' the mornin'-cool,
I walks in my old brown gaiters along o' my old brown mule,
With seventy gunners be'ind me, an' never a beggar forgets
It's only the pick of the Army that handles the dear little pets - 'Tss! 'Tss!

From the poem  Screw-Guns  by Rudyard Kipling

Offline lance

  • Trade Count: (0)
  • Senior Member
  • *****
  • Posts: 1249
  • Gender: Male
Re: Nano-mortar
« Reply #69 on: February 16, 2008, 04:08:12 PM »
THANKS GUYS!!!!    I was too lazy to make it into a cannon or mortar, figured something this small needed to be held anyway,plus i like toothpicks ;D   it's crude,but it does shoot! here's a few specs:No sub chamber, bore very small and 7/16" deep, the vent was drilled with a Dremal round ball bit. Don't know the size,but it is smaller than the bore. no fancy tools in this project,kinda hated to waste a good nail though!........... Darn, i don't know about the Windage factor, never measured the #12 lead balls either. I just found a small bit that made a hole in a piece of wood that those bone crushing balls would fit in, and said looks good to me ;) ;) ;)
PALADIN had a gun.....I have guns, mortars, and cannons!

Offline Cat Whisperer

  • Trade Count: (2)
  • Senior Member
  • *****
  • Posts: 7493
  • Gender: Male
  • Pulaski Coehorn Works
Re: Nano-mortar
« Reply #70 on: February 17, 2008, 03:19:34 AM »
Lance -

BEST put put that into the arms Safe!

If the mice get ahold of it your cat is at great risk!  :D
Tim K                 www.GBOCANNONS.COM
Cat Whisperer
Chief of Smoke, Pulaski Coehorn Works & Winery
U.S.Army Retired
N 37.05224  W 80.78133 (front door +/- 15 feet)

Offline KABAR2

  • Trade Count: (1)
  • Senior Member
  • *****
  • Posts: 2830
Re: Nano-mortar
« Reply #71 on: February 17, 2008, 01:38:36 PM »
Lance,

Now that you have built that everything larger ends up being siege cannon and mortars!

Well who has access to an electron microscope? that's about the only way to take this up a notch.....
Mr president I do not cling to either my gun or my Bible.... my gun is holstered on my side so I may carry my Bible and quote from it!

Sed tamen sal petrae LURO VOPO CAN UTRIET sulphuris; et sic facies tonituum et coruscationem si scias artficium

Offline Terry C.

  • Trade Count: (0)
  • Senior Member
  • *****
  • Posts: 1215
  • Gender: Male
  • I see what you did there...
Re: Nano-mortar
« Reply #72 on: February 17, 2008, 01:57:34 PM »
Well who has access to an electron microscope? that's about the only way to take this up a notch.....

Femto-artillery?

Offline Ex 49'er

  • GBO Supporter
  • Trade Count: (8)
  • Senior Member
  • *****
  • Posts: 1975
  • Gender: Male
Re: Nano-mortar
« Reply #73 on: February 17, 2008, 04:07:35 PM »
I wonder if this could be adapted to a ring setting and worn with a glove could be fired with your arm outstretched. ;D ;D ;D  Or mounted to a ring with a chain strung through it and worn around the neck. ;D ;D ;D   Nano- Gonne jewelry?
When you're walking on eggs; don't hop!!

Offline Cat Whisperer

  • Trade Count: (2)
  • Senior Member
  • *****
  • Posts: 7493
  • Gender: Male
  • Pulaski Coehorn Works
Re: Nano-mortar
« Reply #74 on: February 17, 2008, 04:08:36 PM »
YES!

The new secret weapon of anti-virus serums!

Tim K                 www.GBOCANNONS.COM
Cat Whisperer
Chief of Smoke, Pulaski Coehorn Works & Winery
U.S.Army Retired
N 37.05224  W 80.78133 (front door +/- 15 feet)

Offline seacoastartillery

  • GBO Sponsor
  • Trade Count: (1)
  • Senior Member
  • *****
  • Posts: 2853
  • Gender: Male
    • seacoastartillery.com
Re: Nano-mortar
« Reply #75 on: February 17, 2008, 05:32:17 PM »
     Well, we have finally decided to stick with the plan, and, because of this, we will be building a micro Rodman 10 Inch Seacoast Gun with a .182" bore (#14 drill) which will be about 2.4" long.  It will have a full-depth bore and will be designed to fire solid shot and simple shell.  We will begin on the tube Monday after work.  Almost forgot, an iron casemate carriage is our choice for this diminutive seacoast gun.  Pin-heads for rivets?  Maybe too big.

Regards,

Tracy and Mike
Smokin' my pipe on the mountings, sniffin' the mornin'-cool,
I walks in my old brown gaiters along o' my old brown mule,
With seventy gunners be'ind me, an' never a beggar forgets
It's only the pick of the Army that handles the dear little pets - 'Tss! 'Tss!

From the poem  Screw-Guns  by Rudyard Kipling

Offline Victor3

  • GBO Supporter
  • Trade Count: (22)
  • Senior Member
  • *****
  • Posts: 4241
Re: Nano-mortar
« Reply #76 on: February 17, 2008, 10:26:31 PM »
     Well, we have finally decided to stick with the plan, and, because of this, we will be building a micro Rodman 10 Inch Seacoast Gun with a .182" bore (#14 drill) which will be about 2.4" long.  It will have a full-depth bore and will be designed to fire solid shot and simple shell.  We will begin on the tube Monday after work.  Almost forgot, an iron casemate carriage is our choice for this diminutive seacoast gun.  Pin-heads for rivets?  Maybe too big.

Regards,

Tracy and Mike

 A Rodman??? That's a smoothbore!

 I'm disappointed in you guys.....Can't you set up your rifling machine to make a .010" bore Parrott?

 In fact, I'll buy it from you if it's of the same quality and detail of your larger guns - I'll give you a generous $10 per pound of its weight.

 Deal?
"It is a capital mistake to theorize before one has data. Insensibly, one begins to twist facts to suit theories, instead of theories to suit facts."

Sherlock Holmes

Offline KABAR2

  • Trade Count: (1)
  • Senior Member
  • *****
  • Posts: 2830
Re: Nano-mortar
« Reply #77 on: February 17, 2008, 11:59:10 PM »

A Rodman??? That's a smoothbore!

 I'm disappointed in you guys.....Can't you set up your rifling machine to make a .010" bore Parrott?

 In fact, I'll buy it from you if it's of the same quality and detail of your larger guns - I'll give you a generous $10 per pound of its weight.

 Deal?

Do you mind if they charge you in "scale" pounds?;D
Mr president I do not cling to either my gun or my Bible.... my gun is holstered on my side so I may carry my Bible and quote from it!

Sed tamen sal petrae LURO VOPO CAN UTRIET sulphuris; et sic facies tonituum et coruscationem si scias artficium

Offline Cat Whisperer

  • Trade Count: (2)
  • Senior Member
  • *****
  • Posts: 7493
  • Gender: Male
  • Pulaski Coehorn Works
Re: Nano-mortar
« Reply #78 on: February 18, 2008, 01:11:40 AM »
     ...    we will be building a micro Rodman 10 Inch Seacoast Gun with a .182" bore (#14 drill) which will be about 2.4" long. 
....
Tracy and Mike

I'm in SHOCK!  You're not CASTING the Rodman?  THE significance of the Rodman is the inner-cooling around a mandrel !

Are you not taking great risk at the tube being under strength?

:o
Tim K                 www.GBOCANNONS.COM
Cat Whisperer
Chief of Smoke, Pulaski Coehorn Works & Winery
U.S.Army Retired
N 37.05224  W 80.78133 (front door +/- 15 feet)

Offline seacoastartillery

  • GBO Sponsor
  • Trade Count: (1)
  • Senior Member
  • *****
  • Posts: 2853
  • Gender: Male
    • seacoastartillery.com
Re: Nano-mortar
« Reply #79 on: February 18, 2008, 09:00:21 AM »
     Victor3,  we know that you an accomplished machinist, so you do us great credit by offering to buy a nano-cannon from us sight unseen.  We regret, however, that we will not be able to take advantage of your offer.  This has nothing to do with the fact that our rifling machine cannot do a bore of that size.  We could merely build a miniature copy, and do the job.  That might delay this project about two weeks though, and we are anxious to get going on it.  IF, and it's a BIG IF, we ever did make one for you, we would have to use KABAR 2's idea as the method of computing your cost.  In scale pounds, you would owe us $130,000.00, computed thusly:  Weight of tube (10,000lbs.) + weight of the iron carriage (3,000lbs.)= 13,000lbs. X $10=$130,000.00.  Now, doesn't that sound fair? 

     KABAR2,   Thanks, buddy.  Appreciate that!

     Tim,    We are setting up a miniature version of Fort Pitt Foundry as I write this.  Excellent Idea!!  The only problem we have run into is a supplier of coke for the melting furnace.  The entire foundry will be set up on the kitchen counter beside the sink so we can be very close to our cold water supply.  The miniature fittings were no problem.  Mike used to build gas tanks and fuel lines for RC airplanes.  What a great idea, THANKS!

Mike and Tracy

       
Smokin' my pipe on the mountings, sniffin' the mornin'-cool,
I walks in my old brown gaiters along o' my old brown mule,
With seventy gunners be'ind me, an' never a beggar forgets
It's only the pick of the Army that handles the dear little pets - 'Tss! 'Tss!

From the poem  Screw-Guns  by Rudyard Kipling

Offline GGaskill

  • Moderator
  • Trade Count: (2)
  • Senior Member
  • *****
  • Posts: 5668
  • Gender: Male
Re: Nano-mortar
« Reply #80 on: February 18, 2008, 05:01:59 PM »
The only problem we have run into is a supplier of coke for the melting furnace.

CF&I should be able to supply coke; or maybe a CF&I dealer.
GG
“If you're not a liberal at 20, you have no heart; if you're not a conservative at 40, you have no brain.”
--Winston Churchill

Offline Victor3

  • GBO Supporter
  • Trade Count: (22)
  • Senior Member
  • *****
  • Posts: 4241
Re: Nano-mortar
« Reply #81 on: February 19, 2008, 03:28:19 AM »
     Victor3,  we know that you an accomplished machinist, so you do us great credit by offering to buy a nano-cannon from us sight unseen.  We regret, however, that we will not be able to take advantage of your offer.  This has nothing to do with the fact that our rifling machine cannot do a bore of that size.  We could merely build a miniature copy, and do the job.  That might delay this project about two weeks though, and we are anxious to get going on it.  IF, and it's a BIG IF, we ever did make one for you, we would have to use KABAR 2's idea as the method of computing your cost.  In scale pounds, you would owe us $130,000.00, computed thusly:  Weight of tube (10,000lbs.) + weight of the iron carriage (3,000lbs.)= 13,000lbs. X $10=$130,000.00.  Now, doesn't that sound fair? 

     KABAR2,   Thanks, buddy.  Appreciate that!

     Tim,    We are setting up a miniature version of Fort Pitt Foundry as I write this.  Excellent Idea!!  The only problem we have run into is a supplier of coke for the melting furnace.  The entire foundry will be set up on the kitchen counter beside the sink so we can be very close to our cold water supply.  The miniature fittings were no problem.  Mike used to build gas tanks and fuel lines for RC airplanes.  What a great idea, THANKS!

Mike and Tracy

       

 SOLD!

 You charge me in scale pounds, I pay you in scale dollars (see example of scale Eisenhower dollar coin below). One stipulation - I'll have to insist that you use the .008" drill shown to drill the bore. If you break my drill, I get the cannon for free.



 Whadaya say?
"It is a capital mistake to theorize before one has data. Insensibly, one begins to twist facts to suit theories, instead of theories to suit facts."

Sherlock Holmes

Offline seacoastartillery

  • GBO Sponsor
  • Trade Count: (1)
  • Senior Member
  • *****
  • Posts: 2853
  • Gender: Male
    • seacoastartillery.com
Re: Nano-mortar
« Reply #82 on: February 19, 2008, 04:40:50 AM »
      Victor3,    Let's see; how many ways can you spell SHREWD?  I must admit; I did not see that one coming!!  If we used that teeny, tiny drill, on our electric drill-lathe, we could most likely break it in a NANOSECOND.  As for the micro-cannon, it is progressing slowly.  An idea for using electric ignition via Estes nicrome-wire ignitors did not work out.  We will buy some of those .042", visco, cross-match, fuses  instead.  We're trying real hard to keep the size of the vent down and hence, the pressure up, so it will actually shoot the BB out, not roll it out!  Hope to have a couple pics tonight, late.

     George,    Thank you!  How could we forget about CF&I; they are just 95 miles down the road from us.  We are wondering if they would agree to sell COKE by the cup?  Did you know that they are making 480 foot long RR rails now?  We can understand the mfg. process, but how the heck would you possibly deliver something that long??  Mike says, "By helicopter; they use three Sikorski 'Sky-Cranes', of course." 

Regards,

Tracy and Mike
Smokin' my pipe on the mountings, sniffin' the mornin'-cool,
I walks in my old brown gaiters along o' my old brown mule,
With seventy gunners be'ind me, an' never a beggar forgets
It's only the pick of the Army that handles the dear little pets - 'Tss! 'Tss!

From the poem  Screw-Guns  by Rudyard Kipling

Offline GGaskill

  • Moderator
  • Trade Count: (2)
  • Senior Member
  • *****
  • Posts: 5668
  • Gender: Male
Re: Nano-mortar
« Reply #83 on: February 19, 2008, 07:57:54 PM »
...but how the heck would you possibly deliver something that long??

Railroad rails in long lengths are really quite flexible, especially in relation to the sharpness of curves on railroads.  This youtube video shows a continuous rail train with the rail in the middle and the various machines used to lay it on the end. Here are some stills of the equipment with some text about the process.  Basically the rail is pulled off the series of flatcars through a set of rollers and laid on the ties near the rail to be replaced.  The rail handling machines come along and remove the old rail and set the new rail in place.
GG
“If you're not a liberal at 20, you have no heart; if you're not a conservative at 40, you have no brain.”
--Winston Churchill

Offline seacoastartillery

  • GBO Sponsor
  • Trade Count: (1)
  • Senior Member
  • *****
  • Posts: 2853
  • Gender: Male
    • seacoastartillery.com
Re: Nano-mortar
« Reply #84 on: February 20, 2008, 03:23:40 PM »
     Thanks for that explanation and the excellent photos, George.  I knew helicopters were a joke, but I never realized a piece of steel could be so flexible.

     Well we are finally getting under way with the nano-cannon.  The photos below pretty much tell the story.  Our premise is:  Anyone with a few simple tools can make a small, cute and surprisingly fun to shoot, cannon.  For this project we are foregoing mills, lathes(conventional lathes), bandsaws, etc., etc.


This one is parked in front of the Connecticut State Armory in Hartford, CT.  The dimension tags show full size and nano size, which is a 56.5:1 scale.  This is based on 10" Rodman bore to BB gun dia.bore, .177" dia.




This one shows the elevation sockets on the breech.  Model 1861 caused a change from ratchets to sockets and there is no preponderance either.





This photo is also of a 10" Rodman in Ft Knox, Maine and it shows the lower style, Casemate carriage which we will make.





To make the piece of scrap, .625" dia., low-carbon, rod fit in our drill chuck(3/8"), a few cuts with a hack saw, about 1/2" deep are made to shape the end to a multifaceted design that fits the chuck well.





This is a view of the entire electric drill lathe.  Don't worry about side pressure which could wear out bearings.  We are filing here, NOT cutting with a lathe tool.  Don't forget to grease the tailstock center made from a piece of all-thread filed to a point shown at the left.





Another view showing the guide on the right.  





Some necessary hand tools used are a center punch and four files.  There are double-cut machine files, (fast cutting) and single-cut mill files,(slower cutting) files.  Four grades of coarseness exist:  coarse, bastard, second and smooth.  The two large files are both doulble-cut, one a bastard and one a smooth.  The small files are almost needle file size and are single-cut, one a mill second and one a mill smooth.  After you shape with these, you can go right to 240 grit alox-cloth or wet and dry sandpaper.





This last photo shows the lathe set-up and ready for work; the dimension tagged photo-copy is nearby to keep the shape in view.  Just five licks with that medium size, double-cut bastard machine file got rid of all the rust and reduced that .625" dia. down to about .610" dia. too.  The largest scale dia. we need is .560" dia.near the vent.





     We are cutting the tube thurs. night and will show a very simple method of checking the dimensional size of the tube as you remove metal with those files.  You DO NOT need a pair of electronic calipers.  

Regards,

Tracy and Mike
Smokin' my pipe on the mountings, sniffin' the mornin'-cool,
I walks in my old brown gaiters along o' my old brown mule,
With seventy gunners be'ind me, an' never a beggar forgets
It's only the pick of the Army that handles the dear little pets - 'Tss! 'Tss!

From the poem  Screw-Guns  by Rudyard Kipling

Offline GGaskill

  • Moderator
  • Trade Count: (2)
  • Senior Member
  • *****
  • Posts: 5668
  • Gender: Male
Re: Nano-mortar
« Reply #85 on: February 20, 2008, 08:55:48 PM »
For this project we are foregoing mills, lathes(conventional lathes), bandsaws, etc., etc.

All right, we are being kind of lawyer-like in claiming that we are not using a lathe here.  Certainly it is not a conventional lathe with all of the features that such a lathe would have but it still is turning a workpiece against a (relatively) fixed tool.  I thought you were going to draw file the shape on the barrel, or some other manual process like that.

 ;D
GG
“If you're not a liberal at 20, you have no heart; if you're not a conservative at 40, you have no brain.”
--Winston Churchill

Offline KABAR2

  • Trade Count: (1)
  • Senior Member
  • *****
  • Posts: 2830
Re: Nano-mortar
« Reply #86 on: February 20, 2008, 11:47:16 PM »
For this project we are foregoing mills, lathes(conventional lathes), bandsaws, etc., etc.

All right, we are being kind of lawyer-like in claiming that we are not using a lathe here.  Certainly it is not a conventional lathe with all of the features that such a lathe would have but it still is turning a workpiece against a (relatively) fixed tool.  I thought you were going to draw file the shape on the barrel, or some other manual process like that.

 ;D

You mean as done in the villages of Spain years ago or Pakistan ? Where the "Gum smith" sits on the ground holds the end of the barrel between his toes while he painstakenly draw files the barrel to shape?
I think that's a bit much to ask.......... first neither one of them are short enough to do that with such a small barrel and second if they really must go low tech. they could machine a mold to the proper shape,
heat the offending metal set into the mold pieces and beat it into the cannons basic shape, this is an old
blacksmiths method used for making many items. would that be a better low tech. solution? And they would then have the option of producing more of them! ;D
Mr president I do not cling to either my gun or my Bible.... my gun is holstered on my side so I may carry my Bible and quote from it!

Sed tamen sal petrae LURO VOPO CAN UTRIET sulphuris; et sic facies tonituum et coruscationem si scias artficium

Offline Victor3

  • GBO Supporter
  • Trade Count: (22)
  • Senior Member
  • *****
  • Posts: 4241
Re: Nano-mortar
« Reply #87 on: February 21, 2008, 03:20:37 AM »
For this project we are foregoing mills, lathes(conventional lathes), bandsaws, etc., etc.

All right, we are being kind of lawyer-like in claiming that we are not using a lathe here.  Certainly it is not a conventional lathe with all of the features that such a lathe would have but it still is turning a workpiece against a (relatively) fixed tool.  I thought you were going to draw file the shape on the barrel, or some other manual process like that.

 ;D

You mean as done in the villages of Spain years ago or Pakistan ? Where the "Gum smith" sits on the ground holds the end of the barrel between his toes while he painstakenly draw files the barrel to shape?
I think that's a bit much to ask.......... first neither one of them are short enough to do that with such a small barrel and second if they really must go low tech. they could machine a mold to the proper shape,
heat the offending metal set into the mold pieces and beat it into the cannons basic shape, this is an old
blacksmiths method used for making many items. would that be a better low tech. solution? And they would then have the option of producing more of them! ;D


 Wouldn't it be nice if we all had the skills to do such things...

http://www.armscollectors.com/darra/darra.htm

 Since them Seacoast guys is going 'high tech' with that fancy wooden electric lathe and all, I suspect that their nano-cannon is a shoe-in to win at least 'best of show' here. ;)

 And I can't wait to see it!
"It is a capital mistake to theorize before one has data. Insensibly, one begins to twist facts to suit theories, instead of theories to suit facts."

Sherlock Holmes

Offline seacoastartillery

  • GBO Sponsor
  • Trade Count: (1)
  • Senior Member
  • *****
  • Posts: 2853
  • Gender: Male
    • seacoastartillery.com
Re: Nano-mortar
« Reply #88 on: February 21, 2008, 09:31:12 AM »
     George,  you really had us going for a minute!  Had to read your post 5 times to finally detect the very, very subtle humorous intent in that last sentence and finally spot the "cheesy grin" icon.  Still hoping to inspire some home handy-man without a machine or woodworking shop to make one!!  Mike and I both belonged to this group for about 30 years; certainly no shame in that! 

      KABAR2, with your background in gunsmithing, we know that you really know these things you mentioned to be true.  Your insight here is revealing, in that not too many people know the methods by which those Pakistani gunsmiths produce such accurate copies of the British SMLE and a host of other rifles and shotguns.  You are also correct when you say that this little tube we are making is too short for effective draw filing.  It is.  The forging idea might work better for a crude assy. operation, but we will leave that for someone else to do.

      Victor3,   Thanks very much for giving us that excellent link.  Lots of interesting info. there.   Please don't raise expectations. No, no, no, no; we are making this nano seacoast gun only for fun, because this is NOT a contest and there are no prizes.   We just want to see what's possible when you use basic tools found in a vast majority of households, and have some fun doing it! 

     By all means, if you have the drill-press or bandsaw or maybe a mini-lathe, GO AHEAD AND USE IT !  We are certainly NOT trying to set up some standard set of tools that others must use to the exclusion of more efficient tools that they might own.  We are slaves to historical designs; that's just the way we are.  The good news is that you don't have to be that way.  You have your imagination and hundreds of pre-1898 designs to loosely copy.  The important thing here is motivation;  JUST DO IT !!!  It's actually more fun than watching TV !

Regards,

Mike and Tracy   
Smokin' my pipe on the mountings, sniffin' the mornin'-cool,
I walks in my old brown gaiters along o' my old brown mule,
With seventy gunners be'ind me, an' never a beggar forgets
It's only the pick of the Army that handles the dear little pets - 'Tss! 'Tss!

From the poem  Screw-Guns  by Rudyard Kipling

Offline seacoastartillery

  • GBO Sponsor
  • Trade Count: (1)
  • Senior Member
  • *****
  • Posts: 2853
  • Gender: Male
    • seacoastartillery.com
Re: Nano-mortar
« Reply #89 on: February 23, 2008, 04:37:51 PM »
      Finally had some time to spend on the micro-Rodman.  Photos tell the story:

A little out of sequence, but this is the muzzle end of the tube carefully marked with a scribe along the 90 deg. "V" of a combination square and center punched AND more importantly filed to remove the extruded material around the punch dimple.




This is the dimple flush-filed.  This way your drill does not break thru the built-up material and go off-location.




We drill with the full size drill, a .182" dia. bit in this case.  The vise jaws keep the drill straight L & R as you line it up parallel to them.  We used a bubble level on the elec. drill body which already has shims taped to it.  Check the tube top edge first and then eyeball the bubble as you drill to keep it looking the same.  It won't be perfect, but close enough.



I marked the end of the bore and then center-punched the .055" dia. vent location. The filed area keeps the drill squared and will disappear before the .560" tube dia. is reached.



Rough filed to about .570" dia.  Just .010" to go to get the major tube O.D. between the vent and the trunnions.




A template is layed out on an old for sale sign, about .080" thick stiff plastic.  A couple 6" steel scales would do also, any scale with .020" divisions.  Remember to divide those diameter dimensions by 2 so you will be laying out the cross-section radii which will define the gun's profile every .354" along the bore axis.  This represents 20' on the original gun.




The profile of the tube is then cut away with a coping saw or model-makers or jewler's saw, then filed carefully to the line.




Rough-filed first with the double-cut machine bastard file, you must stay just outside final fit with the template.




Switching to the single-cut mill smooth file and a couple 1/2 round and rat-tail needle files finished the tube profile.





     That's all we had time to do today, about 3 hours worth.  Final sanding with 240, 320, and 400 grit wet and dry paper comes next before removing the drill chuck extension and the first .100" of the muzzle to remove the lathe center.  Trunnions and a little casemate carriage will also be made and assembled.

Regards,  Tracy and Mike








 

 
Smokin' my pipe on the mountings, sniffin' the mornin'-cool,
I walks in my old brown gaiters along o' my old brown mule,
With seventy gunners be'ind me, an' never a beggar forgets
It's only the pick of the Army that handles the dear little pets - 'Tss! 'Tss!

From the poem  Screw-Guns  by Rudyard Kipling