The Alamo, And so it begins. - Page 12 - Graybeard Outdoors
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post #111 of 281 (permalink) Old 06-04-2019, 02:32 PM
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Can't see from the photo, do you have gussets on the brackets underneath?

Every time I look at it, the barrel gets bigger and the band gets smaller.

.

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post #112 of 281 (permalink) Old 06-04-2019, 02:57 PM Thread Starter
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Can't see from the photo, do you have gussets on the brackets underneath?

Every time I look at it, the barrel gets bigger and the band gets smaller.

.

No gussets on there. Might not be a bad idea though.
I'll look at it when I test fit.
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post #113 of 281 (permalink) Old 06-04-2019, 06:57 PM Thread Starter
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Quote:
Originally Posted by Terry C. View Post
Can't see from the photo, do you have gussets on the brackets underneath?

Every time I look at it, the barrel gets bigger and the band gets smaller.

.



Terry C.
I have been thinking about the "gusset" idea.
I don't see why they are needed.


Look at these pictures. Here is some more info on them.
The material of the collar is 3/8" X 7" wide.
The gap between the flange plates welded to the underneath side is 1".
The gap allows me a little wiggle room for lateral movement when fitting the collar.
The flange plates are 7" wide and will accept three 5/8" splice bolts.
I have an assortment of 3/8" and 1/4" spacers with the same three holes in them to put in between the flange plates as needed so I can tighten the 5/8" bolts really tight.


The flange plates can't bend in because of the spacers.
They can't bend out because three 5/8" bolts across 7" just won't allow it.


That's my reasoning anyway.
I believe the majority of the weight of the 2240 lb. barrel will be sitting on the leveling screw platform.


The collar has an open top.
The top horizontal line of the trunnions is equal to the height of the center line of the bore.
This is how below center trunnion guns were engineered.


Some of the collar extends above the center line of the bore. This actually captures the barrel preventing it from "jumping" out of the collar.


The spread of the top of the collar is less than the spread of the barrel at the center line of the bore.


Anyone see any holes in this?
Zulu








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post #114 of 281 (permalink) Old 06-04-2019, 10:56 PM
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I believe the majority of the weight of the 2240 lb. barrel will be sitting on the leveling screw platform.


I am assuming the barrel will be supported by the elevation screw and the trunnions and nothing else. If that is true, each trunnion will be supporting one half of the difference between the total weight and the preponderance. It is my opinion that the space between the tabs should be filled with a solid block to prevent the tabs from bending. (I am guessing that what you call flange plates, I am calling tabs. How thick are these pieces? How are they welded?)


I am also thinking I would use 5 bolts instead of 3; not because 3 bolts wouldn't carry the load but because 5 would spread the load across the flange plates more evenly.

GG
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Last edited by GGaskill; 06-04-2019 at 11:08 PM.
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post #115 of 281 (permalink) Old 06-05-2019, 12:26 PM Thread Starter
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I believe the majority of the weight of the 2240 lb. barrel will be sitting on the leveling screw platform.


I am assuming the barrel will be supported by the elevation screw and the trunnions and nothing else. If that is true, each trunnion will be supporting one half of the difference between the total weight and the preponderance. It is my opinion that the space between the tabs should be filled with a solid block to prevent the tabs from bending. (I am guessing that what you call flange plates, I am calling tabs. How thick are these pieces? How are they welded?)


I am also thinking I would use 5 bolts instead of 3; not because 3 bolts wouldn't carry the load but because 5 would spread the load across the flange plates more evenly.



George,
You are correct. The only things supporting the barrel are the trunnions and the leveling screw.
The space between the "tabs" will be filled with solid spacers the same size as the "tabs".
The "tabs" are 3/8" material, 7" long. Currently, they are just tack welded until I am sure this thing is going to fit.


There is no way five 5/8" bolts will fit in a 7" span. I am very comfortable with three of them.


Poor pictures. I will get some better ones when it stops raining.
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post #116 of 281 (permalink) Old 06-05-2019, 12:58 PM
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I think what you have will work just fine. The majority of the weight will go into your faux trunnions. If the bottom screws and flange are not tightened correctly the weight will push the bracket down and force the top of the bracket to close and pinch towards the barrel in the trunnion area.

The bolt will have some force directed to them, but not that much.

Your biggest challenge will be to adjust the bottom bolts so the trunnions stay level when the faux trunnion supports the barrel weight. If you can get good solid contact between the barrel and the radius of your bracket that will reduce and eliminate the pinch at the top and the bracket will act as a cradle. Even then your faux trunnion will still carry the weight to the carriage-trunnion plates

Underneath you will still need spacers, but of variable thickness. The spacers are to keep the flanges from pulling in and bending or breaking. You only need enough spacer width to be held by the bolts under light tension. I would use Red loctite on the threads. You may need feeler gauge thickness spacer to go with the main spacer.

I like those square nuts, good touch.

Last edited by double d; 06-05-2019 at 04:02 PM.
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post #117 of 281 (permalink) Old 06-09-2019, 02:53 PM Thread Starter
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Seems to be a pretty sleepy forum these days.
Here are some more pictures of the collar. I have been working on the capsquares.
I am off to The Alamo tomorrow to make sure the collar fits.

Wish me luck!!
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post #118 of 281 (permalink) Old 06-09-2019, 03:06 PM
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Spacer is too narrow. It should come right up and be the same height as the radius. The surface of the radius and top of the spacer should be more or less one contiguous surface. If left as is, there is a real chance the bracket portion will bend just above the spacer from the weight, unless the radius is full contact and weight distribution is uniform on the radius. I also think the gap between the two halves is too wide. It should be as narrow as possible.

Otherwise it looks very nice. Well done.
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post #119 of 281 (permalink) Old 06-09-2019, 03:32 PM Thread Starter
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Quote:
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Spacer is too narrow. It should come right up and be the same height as the radius. The surface of the radius and top of the spacer should be more or less one contiguous surface. If left as is, there is a real chance the bracket portion will bend just above the spacer from the weight, unless the radius is full contact and weight distribution is uniform on the radius. I also think the gap between the two halves is too wide. It should be as narrow as possible.

Otherwise it looks very nice. Well done.



Just above the spacer hasn't even been welded yet. I have to see if it fits first.
The gap between the two halves is necessary. Without the barrel in my possession, I have to have room for mistake.
There is a great deal riding on this thing fitting.



And I'm dealing with a barrel that was cast in the early 1700's, is very heavily pitted, may be out of round, and most certainly is not perfect.


I will know tomorrow.
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post #120 of 281 (permalink) Old 06-09-2019, 08:48 PM
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My suggestion is that once the correct gap has been established, the space above the filler should be filled with weld deposit. Looks like that is where you are going anyway. With a sound weld in there, the bolts won't be doing anything.

GG
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