Author Topic: 10" Gribeauval mortar drawing (Read 7900 times)

accuratemike · « **on:** March 19, 2006, 07:55:54 PM »

OK. I've had time to digest GGaskill's fine print and re-do the drawing (more) to scale. Again, the bore and chamber are arbitrary. The piece is in the lathe and the OD cleaned up. (hence, the new major diameter is .035" smaller) Scale is 17.5% (1.75"/golf ball bore). I'll be making chips soon. Thanks for your help and input, MIKE

GGaskill · « **Reply #1 on:** March 19, 2006, 08:27:32 PM »

Glad to be of help. Just so credit is given where it is due, the drawings are from Round Shot and Rammers by Harold L. Peterson, published by South Bend Replicas, South Bend, Indiana. The drawing is not credited but the illustrators of the book are Peter F. Copeland, Donald W. Holst and Robert L. Klinger.

Cat Whisperer · « **Reply #2 on:** March 20, 2006, 01:27:36 AM »

Quote from: GGaskill

Glad to be of help. Just so credit is given where it is due, the drawings are from Round Shot and Rammers by Harold L. Peterson, published by http://www.specialtymile.com/southbendreplicas/index.htm" target="_blank">South Bend Replicas, South Bend, Indiana. The http://68.190.219.22:443/images/gribeauvalmortar2.gif" target="_blank">drawing is not credited but the illustrators of the book are Peter F. Copeland, Donald W. Holst and Robert L. Klinger.

Thanks George!

(What is the difference between plagerism and research? - - - - footnotes.)

accuratemike · « **Reply #3 on:** March 20, 2006, 11:09:06 AM »

I'm glad you posted the page for me. I doubt you'll ever see the drawing anywhere else, but if so, I'll be sure to give the proper credit. Enjoy, MIKE

CU_Cannon · « **Reply #4 on:** March 20, 2006, 11:25:45 AM »

I recommend the book highly. I just picked up a copy of eBay for around $14 and that was after shipping. It was well worth the price. The current price on Amazon is about $20.

GGaskill · « **Reply #5 on:** March 20, 2006, 02:33:29 PM »

Probably less from SBR.

accuratemike · « **Reply #6 on:** April 23, 2006, 07:33:31 AM »

It is finally out of the lathe. Now for trunions/pockets...

When it is done, I'll start a thread with some pics of the build.
Enjoy, MIKE

Powder keg · « **Reply #7 on:** April 23, 2006, 07:42:05 AM »

lookin good Mike!! How are you planing on holding the trunnions on?

Wes

accuratemike · « **Reply #8 on:** April 23, 2006, 07:54:14 AM »

Good question. I haven't decided. Either I'll take it to work and TIG them, or, I'll JB weld them (to keep in the spirit of the "home shop" project). I know the TIG will hold them in, I suspect the JB weld will too. I worked in an auto parts store as a kid. The JB Weld display had two valves, glued head-to-head, on it. It was like they threw down the gauntlet. We couldn't bust them apart, even with leverage. Judicious application of heat did it eventually. I actually have LPS "Strong Steel Stick", "Marine Tex" and LPS "Aqua Bond" here. I think they are all of the same ilk. We'll see how I do with my pockets

MIKE

Rickk · « **Reply #9 on:** April 23, 2006, 07:59:18 AM »

epoxy has way more strength in pull force than shear force... JB Weld will most likely not do the job.

Assuming that is brass as the color appears, solder would not bee too hard.

accuratemike · « **Reply #10 on:** April 23, 2006, 08:29:05 AM »

It's steel, I think the color is reflection of the mostly brownish wood stuff in the shop.
I was considering JB weld (or similar), these two threads covered some of the points.
http://www.graybeardoutdoors.com/phpbb2/viewtopic.php?t=70288
http://www.graybeardoutdoors.com/phpbb2/viewtopic.php?t=74940
I still may weld, I haven't drilled/bored for the trunions yet (or turned/polished/cut the trunions either). Just thinking. MIKE

CU_Cannon · « **Reply #11 on:** April 23, 2006, 09:32:10 AM »

Great looking work!

Now I have something else added to my list of stuff to build.

I have used JB Weld on a couple of the mortars I've built. The materials used were unweldable in all practical cense. Also they were of the coehorn design with socket screws doing most of the work. To attach the trunnions on this mortar I would recommend you weld them. I think you will be happier with it in the long run. I would only use JB Weld in this application if you didn't have access to the equipment.

Rickk · « **Reply #12 on:** April 23, 2006, 09:48:48 AM »

Brownells gunsmithing supplies carries a solder and flux that works on steel. The reflow temp is not all that high. A propane stove for preheat, in combination with a propane or mapp gas torch should get you up to temp.

You may be able to get up to brazing temperatures if you can borrow a oxy-porpane or oxy-acetlene setup, but a propane stove preheat would still be wise. It would reduce the amount of localized heat you will have to apply.

accuratemike · « **Reply #13 on:** April 23, 2006, 10:03:33 AM »

We have a nice, big, TIG machine at the shop. And a similar operator to go with it. I was leaning that way anyhow. Powder Keg brought it up.

I'm hoping he (Jim, the nice, big, welder) will leave me just enough weld that I can die-grind and blend, avoiding the "fill" (bondo) part. It is so pretty, I can hardly bear to see him strike an arc on it. Still, I am two (or three) steps from that point. MIKE

Blaster · « **Reply #14 on:** April 24, 2006, 02:19:48 PM »

Kansas Cannon Works does use JB Weld in their trunions. If you check out their web site, you can read their discription about it. I have asked the owner, Bill, if he has ever had any customers experiencing problems with the JB Weld. He told me "None that he was aware of". This is just as information for ya.
Blaster (Bob in So. CO)

accuratemike · « **Reply #15 on:** April 24, 2006, 03:01:39 PM »

I have seen that too.

MIKE

Double D · « **Reply #16 on:** April 24, 2006, 03:24:55 PM »

Here's your test. Make a dummy socket and trunnion. JB weld the together. put the piece with the dummy socket in it in a vice.

Take a 10lb sledge and whack the trunnion. Do it until it is obvious that the metal willl bend before the JB weld fails, or the jb weld fails. Be sure and report back the results.

If you can get them TIG welded do it!

accuratemike · « **Reply #17 on:** June 30, 2006, 10:54:51 AM »

Trunions !!!

They are in. And they ARE TIG welded.
1 3/8" diameter, and they stick out 1 1/2" from the barrel band on each side. The Mortises are .222" deep. .0015-.002" press.
Now, on to the base. ( I'll post-up all of the finer details when it is done )
Enjoy, MIKE

Double D · « **Reply #18 on:** July 01, 2006, 04:21:43 AM »

Aw darn I wanted to see the result of the KB weld hammer test!!!

Well Mike it's looking pretty good!!!

Tropico · « **Reply #19 on:** July 04, 2006, 05:48:36 AM »

The mortar looks much better than the blue-print. That muzzle is great !!!

accuratemike · « **Reply #20 on:** July 04, 2006, 07:30:52 AM »

Thanks guys!

Temporary base. And you can tell by the filth on the barrel....she has spoken. I mowed a 336' fairway and am working on range. Balls vary in diameter. Diameter changes windage and pressure (and range). I've had to mic my balls and check the range on each ball. A full load will send the balls into a parallel universe. Around a teaspoon seems to be working with the smaller balls going 75 paces or so. It's too hot to walk around in the sun now, so I am working on drawing the parts of the scale base. She'll be back in action this evening, after all, it is the 4th. of July !
Enjoy, MIKE

Double D · « **Reply #21 on:** July 04, 2006, 10:18:15 AM »

One of the things that occurred with changing over to the new software was tha lings in a post were broken. This post was linked in our Cannons plans sticky. CW and I will have to relink everything.

I'll start with this post. It also appear that the new software to doesn't support HTML. At least one post in this thread has HTML in it and appears to be read.