Tannenberg Gonne

[Powder keg]

Hello, It seems like every time I go to start the contest mortar a "Paying Job" walks in. Unfortunatly I haven't finished it by the deadline and will not be able to enter. On to better things.

I was recently asked to build a Tannenberg hand gonne. After the deal was struck I thought to myself? How can I easly make a nice looking, tapered octagon. The octagon wasn't the problem. It was the taper. I wanted to be able to easly produce tapers using the sides of my endmills, not the end(easer to clean up the mill marks).  So, I built a taper attachment for my mill. No I've never seen one before, I just thought , Why should the lathe have all the fun  I added 1" spacers under it so it would clear the handles on my mill.

Machining of the gonne to follow soon. I have to finish the chuck adaptor
 for my dividing head. I have the gonne drilled for the tiller and the bore drilled and reamed .50 caliber. More pictures later,
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[HotGuns]

Interesting idea that proves that there is more than one way to skin a cat...

I like it.

The tailstock for my dividing head had an offset that will give a pretty good taper, its what I use since its there..of course the length of the taper is a factor.

Im thinking that a slotted plate that sits under the tailstock and a different one for the headstock would do the same thing and use less steel. That way you could pivot each one or both and tie them directly to the t-slots in the table.

[Powder keg]

Hot Guns, Your Idea is a good one also. I also wanted to position my dividing head's chuck so it was at the end of the table travel on my mill. This ment that the dividers body would have to be over the handwheel. Hence the big piece of iron. Now I can utalize the full travel of my smallish mill table if needed. Also I think I can set the tapers pretty fast in case I wanted to make several of the double angled Tannenbergs (for instance).

[Powder keg]

Interesting idea that proves that there is more than one way to skin a cat...

I ment to add. I work with a guy that says that all the time. If he thinks your idea isn't good he adds "but sometimes we'd like to keep the hide" and then he'll go on and tell you the way he thinks it out to be done :?

[Cat Whisperer]

Hello, It seems like every time I go to start the contest mortar a "Paying Job" walks in. Unfortunatly I haven't finished it by the deadline and will not be able to enter.   ....  

Keep it going during the 'off' times - I don't think DD put a YEAR behind that September 1st deadline.


Thanks for the pix on the setup - I've got a piece of aluminum that I've been saving for a fixture.

[kappullen]

Here is a neat tool for the lathe I picked up a while ago.

This is a mechanical tracer attachment.



This tool has a stylus that follows the flat .125 thick plate contour.
This job is a golf ball mortar and the template is to form the spherical bore
for the ball.



Here you can see the tool about to enter the bore and the stylus near the
layout line on the template.

For those octagonal handgone jobs I have a Cinncinatti Tracer Mill that will
follow any form on a template, or other origional barrel.

It's like a poor mans cnc mill.

They come up cheap on ebay because no-one remembers how to use one anymore but
dinosours like me.

I haven't used it for cannon work yet.

Here is a golf ball mortar I just made.



Hope you don't mind me throwing ideas out there.

kap

[Powder keg]

Thanks Kap! I love Ideas. could you elaborate in your little gizmo? I think I've almost got how it works in my head. Sounds handy. What does the clamp do? maybe i need a couple more pictures or something. Oh, Nice looking mortar! You sure do nice work!!

My taper attachment wasn't done in the pictures I posted last. I almost am ready to start milling the octagon.  I mounted the 3 jaw chuck onto the dividing head. I shortened the mounting bolts that bolt the unit to the table.  I made the extra T-nuts I needed to bolt everything to the table. And I assembled everything ready for tomorrow evening. I also glued the arbor to the gonne. I've used this trick before. I'll give more details if it works out.

[Cat Whisperer]

kap -

I've been collecting bits and pieces of steel to build a tracer attachement to do the spherical radii like you've pictured.  THANKS for the pix.  A few more would help.  I like the idea of turning the rig to 45 degrees to do the bores and things like moulds.

[kappullen]

That little gizmo turned up on ebay a couple years ago for $150.

Here is the template holder.
It clamps on two v blocks on the ways and the bolt on the vertical part is the depth adjustment.





All tracer lathes that I know of operated on a 45 degree angle.

On a mechanical tracer, the tool has to be going out of the cut at all times.
That means the template has to be letting the tool out of the cut instead of pushing into it.

There is no power to push it into the cut like a powered Hydrolic) one.

The "c" clamp is to dampen chatter. The whole setup is rather rickety.

If you search here, issue # 21 there are some more pictures of the unit.

http://www.discoverlivesteam.com/magazine/A-e-magazine.htm

I'm into that stuff from time to time.

I can take more close ups of details if you'd like.

Kap

[Powder keg]

Here is 2 1/2 Hours on the mill. Didn't take time to clean up for pictures. Whole setup worked out very good. I'm happy with my efforts in building the tapper attachment. I changed the dimensions slightly because of the reduced bore. I went with 1.625" shaft.

Kap, wonderful pictures! Thanks! But I'm still missing something :oops:  I've never been around or seen a tracer lathe before. Would be interested in building that unit. Looks very handy for the stuff I do. Please PM me.

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[GGaskill]

So what alloy did you/your customer decide to use?

[Powder keg]

We decided to use 1018. It's a good thing because 4340 would have taken forever to mill! I'll bet the vent drilled today and post some more pictures.

[kappullen]

Powder Keg,
Here is a tracer attachment I made that really didn't work for acute tapers but may work for gradual tapers.





This relies on pushing the carriage but I had to help things along a bit.
I was making a die for pressing bobs for sites.

The form mounts on the tailstock spindle.

I redid it so the carriage didn't have to be pushed but don't have a photo of that right now.

kap

[kappullen]

Here's the redone tracer, but I never had a chance to try it out.





We used a unit similar to this for machining curves on gear blanks for shaft couplings years ago.

kap

[Powder keg]

I got the vent and the screw hole in the tiller socket drilled today. Here is a picture .



When setting the piece up in the mill I ran into the problem of how to hold it. To solve this problem I decided to use an arbor that glues in. The brand dosen't matter much. I used crazey glue brand super glue. the arbor is turned about .010 smaller than the bore and glue is applied to the arbor. I insert the arbor with a twisting motion to evenly coat the shaft as it it inserted. I let it set for about 15 minutes and started to mill the octagon.

Super glue breaks down at high tempature. So to remove I applied heat from my foundry burner and with a pair of pliers the arbor slid out. I'm guessing the temp was around 700 degrees.

[Cat Whisperer]

That's cool.  

LocTite in it's various forms also goes soft plastic when hot - and you've got several strengths to play with.  It also swells a little when setting up.

I wonder what it would like if it were jeweled/engine-turned?

[Powder keg]

I've used super glue for several other applications. I've glued flat thin sheet metal to a faceplate to make discs or rings for example. Just keep it cool or it will come un-glued :shock:

Jewling would be a nice touch to this piece I think.

[Powder keg]

I liked the way the first one turned out that I decided to make another one. As I was milling the recessed part of the octagon, I thought that people would be interested in my settup. Notice the two black nuts at the bottom. Those are the stops I set so the flats are all the same legnth. Later,

 

[Cat Whisperer]

THANKS for that picture and explaination!

Simple but so easy!

[Powder keg]

I got two of these done this weekend. I'll post pictures later. I was going to start a bronze cannon but I got a call from my uncle. He said the Fire department was at my parents house cutting holes in the roof to put out the fire :shock:  So I didn't get any more done. Luckley everyone was Ok. Mainly water and smoke damage. Mom was burning a stump, cought the grass on fire, cought the pine trees on fire, and so on. Here's a picture.

[Cat Whisperer]

Powder keg -

Sorry to hear of the fire, rejoice with you that no one was hurt.

I like you pictures of handgonnes better -

[Powder keg]

Hello All,
I had a chance to make a couple more Gonnes. The bronze one is mine, all mine I still need to drill the vent and a hole for the screw that holds it to the tiller. Also I'm going to put a mirror polish on it. I  built the bronze gonne a bit heavyer than the steel ones to be on the safe side. I'll shoot it this weekend and post results. I wanted to get a couple more done while my mill was still set up to cut tapered octagon's.

Later, Wes

[GGaskill]

Nice work.  Were they all done with a single taper?

[claypipe]

Definitely quality work.

Nice Indeed!

[Powder keg]

Hi GGaskill,
Yes, their just the single taper ones. I might make a couple double tapered gonnes in the future? I'll just have to see.