Author Topic: A. Roads: Question about British block trail carriage (Read 4492 times)

gary michie · « **Reply #60 on:** August 29, 2008, 06:01:52 PM »

Hi:

there is another thing that I see with your pic/drawing post the artist missed with the azimuth device.The cheeks were bolted on to a plank or slab of iron then you moved it with the cross handle. you can't do that when the cheeks are bolted to the sides of the trail ,but a bolt would be there if the cheeks were standard.
Gary

Cannoneer · « **Reply #61 on:** August 30, 2008, 02:16:23 AM »

It seems like this draughtsman was also prone to improvisation when he copied the wheels; there are three bolt heads between the spokes when viewing the strakes attached to the soles of the felloes and there are two nuts visible between the spokes on the backs of the felloes. It also appears like some of the bolts are going directly into the tongues of the spokes when looking at the wheel from an outside perspective.

A.Roads · « **Reply #62 on:** August 30, 2008, 11:56:19 AM »

"it appears that there is a metal or wood brace in line with the trunnion holes that is part of the construction of the latter era carriage (unless it's an optical illusion). "

Here is a close up of that area.
Adrian

Cannoneer · « **Reply #63 on:** August 31, 2008, 01:39:32 AM »

Thanks much Adrian, your photo makes it a lot easier to discern the metal frame-work that is there; when I was looking at the enlarged photo I posted, it seemed at times like it just might be a shadow.

gary michie · « **Reply #64 on:** August 31, 2008, 06:02:18 PM »

Hi:

Now I see how the azimuth adjustment works on this carriage ,the metal brace is bolted to the trunnion seats and there caps. There is probably a bolt going through the trail and axle from the bottom of this brace to form the pivot point.

A.Roads · « **Reply #65 on:** August 31, 2008, 11:41:59 PM »

There is a "pivot" bolt as you suggest - surprisingly not a very substantial one - but it is difficult to tell if it goes through the axle when you see its position on the upper side of the trail - there is a bolt/screw/rivet on the underside of the axle , but I suspect that they are not the same item.
Adrian

Cannoneer · « **Reply #66 on:** September 02, 2008, 06:31:14 AM »

I found one more pic in my labyrinth of saved photos that echoes the angle of Adrian's second photo of the Australian carriage. Gary, your theory that the brackets are attached to a framework that allow the cheeks to be moved a slight degree either left or right seems like it might be wrong; look at the three most recent posted photos and I think you'll agree that those cheeks don't appear like they can be moved in either direction, they certainly seem to be firmly attached to the block trail. The draftsman that copied the nut on a bolt at the bottom rear of the bracket was copying the photo accurately. I was misunderstood in an earlier post where I mentioned a concavity carved out on the rear edge of the cheek itself (I suppose an architect or furniture maker might call this "concavity" an ovolo with a filet) and you can see in Adrian's photo the three screw heads that are securing the cheek to the trail on this part of the cheek. The photo of the underside of the carriage shows no gap between the inside surface of the bracket and the block trail. I think this might be what you're saying in reply #64 but I'm not sure.

I wonder how long it took for the gun crews to abandon trying to utilize this traversing mechanism to move the barrel left or right and revert back to the tried and true trail spike? Adrian's observation that this "pivot" bolt is suprisingly unsubstantial should probably be considered an understatement. It's amazing to me that almost the entire weight of this barrel is resting on a metal framework that actually seats the tubes trunnions and holds the cannon secure with cap squares that are attached directly to this same framework and that the whole gun and framework together are moved either to the left or right by turning a screw that moves a flat piece of steel mounted on a pivot that in turn moves the whole framework to either side depending on which way the screw is turned.

This might be a good time to revisit Guardsgunner's post with the Charles Knap quotations; I can just imagine a Confederate cannoneer standing on the field of battle watching a gun crew muzzleloading a Whitworth 12 pdr with it's breech-block locked, then traversing the gun with the use of the carriage's trail-spike and him then remarking that it's just wonderful the great strides we're making in technological innovations, I wonder what they'll come up with next.

gary michie · « **Reply #67 on:** September 02, 2008, 07:56:00 AM »

Hi:

So the "pivot" for the trunnion is that bolt up ahead of the adjuster on the lever from going to the brace that is bolted to the trunnion seats and caps. And ,and, now there is a second bolt with a rosette type of washer for a square headed bolt, is there a third?

?
ANY MORE PICS?

Cannoneer · « **Reply #68 on:** September 02, 2008, 09:36:56 AM »

Quote from: gary michie on September 02, 2008, 07:56:00 AM

Hi:
So the "pivot" for the trunnion is that bolt up ahead of the adjuster on the lever from going to the brace that is bolted to the trunnion seats and caps. And ,and, now there is a second bolt with a rosette type of washer for a square headed bolt, is there a third??
ANY MORE PICS?

Gary,

I think I've hit a low tide on photos of this carriage, your last best hope is probably going to be Adrian.

cannonmn · « **Reply #69 on:** September 02, 2008, 11:56:17 AM »

I have a number of photos of an Armstrong b/l at Ft. Nelson, showing a lot of detail, marks, mechanism, etc. if anyone wants them posted, otherwise I'll save the bandwidth.

gary michie · « **Reply #70 on:** September 02, 2008, 06:22:15 PM »

please

cannonmn · « **Reply #71 on:** September 02, 2008, 08:08:45 PM »

These photos were taken at Ft. Nelson, near Portsmouth, England, by Jim Schoenung of CannonRest. I just noticed that this must be the same gun that BoomJ showed a photo of a few posts back.

cannonmn · « **Reply #72 on:** September 02, 2008, 08:23:01 PM »

More photos, also Ft. Nelson, credit also to Jim Schoenung, CannonRest. I know the sign on the gun says "do not do it" but I'd be sorely tempted.

gary michie · « **Reply #73 on:** September 04, 2008, 03:21:56 PM »

Hi:

Does any one know if the wheels are 57" or should I ask what is the dim. of the wheels?
Gary

GGaskill · « **Reply #74 on:** September 04, 2008, 05:23:36 PM »

It's a 12 spoke wheel.

Max Caliber · « **Reply #75 on:** September 05, 2008, 01:59:17 AM »

Not sure what diameter wheel this gun had but the British did not use 57 inch wheels. They used 60 inch wheels on this size gun. The British and Germans generally used 12 spoke wheels and the Americans and French used 14 spoke wheels, at least up to the time the heavy B/L guns came into use.

Max

Cannoneer · « **Reply #76 on:** September 06, 2008, 03:16:06 AM »

I'm basically just restating what Max has already posted. General Thomas Desaguliers designed a new type of artillery carriage in 1775 that was called a 'block-trail' carriage, his NEW design was based on a light carriage captured by the British on the island of Martinique in 1761. In military documents the block-trail carriage was designated as a 'new pattern' carriage while 'old pattern' referred to the 'double- bracket' carriage that had been in service for many years. In the late 1700's when the old pattern carriages were being replaced by the new pattern block-trails the standardized wheel size of the new pattern was designated as five feet and this was also the same size wheel to be used on all other artillery equipment just as in America at a later date the 57 inch wheel was standardized for our three field carriage models and also for their limbers and caissons. The materials used for the British new pattern wheels remained the same as the old pattern, elm for the hub and felloes with spokes being made of oak. As far as I know this block-trail carriage and 60 inch wheel size remained the British standard for almost three quarters of a century.

gary michie · « **Reply #77 on:** September 06, 2008, 06:22:28 PM »

Hi:

OK so I go to my AOP Augusta drawings that has a scale and measure the wheel and with out the tire it measures 60" with tire 61.75. Now is a wheel measure with or with out tire and who has heard of a 7/8" tire thickness ?
I am thinking more and more that this publication (#23) is just a bunch of cute pictures.

Max Caliber · « **Reply #78 on:** September 07, 2008, 01:54:28 AM »

Gary, The diameter of the wheel is measured with the tire on. I have not seen any references to cannon tires that were 7/8 inch thick but have seen and owned wagon wheels made for use in rocky conditions that had tires that were 5/8 inch thick. Metal tires running on rocky roads would stretch from the hammering of the rocks just like a blacksmith hammering iron on an anvil. Around here in the soft sand, wagon tires were thinner and wider.

Max

Cat Whisperer · « **Reply #79 on:** September 07, 2008, 02:31:21 AM »

It is (was with pencil/ink) a common practice to 'distort' the drawing a little so that the drawing is readable - since OFTEN the measurement would be so small that two lines would (in a scaled drwing) actually overlap. Hence, one will see 'do not scale drawing' as a standard remark.