Another Grand Union Lock

[MtB]

2 hours ago, alan_fincher said:

I agree!

 

If you accept that the current house is a replacement or at least partial rebuild, then Matty's suggestion seems a good 'un.

 

I think it's probably the other way around. Given the tiny chance of there being two identical locks, both with the same rise and both having a house in the exactly same place, I'd suggest the probabilty is the house was remodelled!

 

 

[Victor Vectis]

22 hours ago, beerbeerbeerbeerbeer said:

for novelty, I like using them,

especially when they work proper and you can leave them to lower without winding them down,

 

Oooooooo.......

 

You'll get told off for doing that!

 

ETA (One might wonder how I know this)

Edited December 24, 2023 by Victor Vectis

[magnetman]

There is an internal shock absorber on the original design.

[Richard Carter]

2 hours ago, alan_fincher said:

I agree!

 

If you accept that the current house is a replacement or at least partial rebuild, then Matty's suggestion seems a good 'un.

 

Google Earth image suggests a substantial towpath side extension with the former gable end now buried in it

 

Was/is it owned by the Matts of FBS? (I know, I ought to know, but I think it was a bit after my time there ... )

[Steve Priest]

35 minutes ago, Victor Vectis said:

Oooooooo.......

 

You'll get told off for doing that!

 

ETA (One might wonder how I know this)

If you get told off again show them this -“closing is by gravity”!
 

Yes, there is a rubber pad to absorb the shock, I understand that there were two more pads fitted to the bottom of the paddle frame which are no longer fitted after changing from wood to plastic paddles

[Richard T]

37 minutes ago, Richard Carter said:

 

Google Earth image suggests a substantial towpath side extension with the former gable end now buried in it

 

Was/is it owned by the Matts of FBS? (I know, I ought to know, but I think it was a bit after my time there ... )

I think that it was owned by the Matts family.

[MtB]

2 hours ago, magnetman said:

There is an internal shock absorber on the original design.

 

Was there? I've never noticed that in the cross sectional drawings. 

 

There IS however, supposed to be a thick rubber pad for the spiral to bounce on when it gets to the bottom, but often missing so dropping the paddle results in a brutal 'clonk' when it gets to the end of its travel. Hence the instruction from CRT to wind them down manually.

 

 

 

 

[magnetman]

The rubber pad is what I call a shock absorber. 

[beerbeerbeerbeerbeer]

2 hours ago, Victor Vectis said:

Oooooooo.......

 

You'll get told off for doing that!

 

ETA (One might wonder how I know this)

yes, it does pay to care,

some do work smoothly and gently,

while others drop with a clunk or more irritatingly stick/stop half way down,

 

 

[MtB]

11 minutes ago, magnetman said:

The rubber pad is what I call a shock absorber. 

 

Ah. 

 

This is my idea of a shock absorber:

 

[magnetman]

Yes but that is for a car. 

 

 

 

The words need to be isolated from each other.

Shock...absorber. 

 

Something which absorbs shock. 

[beerbeerbeerbeerbeer]

[magnetman]

 

 

I suppose Rubber Damper would be more accurate and lead to less confusion.

 

 

Not to be confused with Rubber Tapper. 

[Captain Pegg]

The replacement of the original wooden infill to the paddles with plastic is another reason to wind them down. The wood had a degree of give to it that the plastic doesn’t have and they are prone to cracking if the paddles drop sharply.

[Ray T]

5 hours ago, Steve Priest said:

If you get told off again show them this -“closing is by gravity”!
 

Yes, there is a rubber pad to absorb the shock, I understand that there were two more pads fitted to the bottom of the paddle frame which are no longer fitted after changing from wood to plastic paddles

I don't know why the myth persists that Ham Baker paddle gear is hydraulic, it is not.

 

Improvements in or connected with penstocks, sluice valves and the like United Kingdom Patent 387951-A

387951-A is referenced by 1 patents.

387,951. Sluice valves. BENCE, E. H., Municipal Engineering Works, Langley Green, Birmingham, HAM, P. S., 70, Victoria Street, London, and MORGAN, E. I., 8, Wolverhampton Road, Sedgley, Birmingham. Aug. 24, 1932, No. 23694. [Class 68 (ii).] A sluice valve is operated by screw gearing of such a pitch that the valve, when raised and released, will descend by its own weight. The Figure shows a gearing for raising a flat sliding valve, not shown, at the lower end of a non-revolving rod 14. It comprises a gear case 19, 20, containing bevel wheels 23, 24 rotatable so that the nut 35 raises the rod 14. When raised, it is retained by pawls 33a, 33b engaging with ratchet wheels 30, 31 ; these may be released by overturning a link 34, and the valve then descends. The stop 37 is fitted with a buffer 38, or may function as a dashpot.; In a modification, the rod 14 is keyed to the wheel 23, and rotates in a nut at the upper end of a tube attached to the valve rod. Buffers are fitted at the lower edge of valve ; they may be removed to enable the valve to be removed.

Title Improvements in or connected with penstocks, sluice valves and the like Application Number GB19320023694 19320824 Publication Number 387951 (A) Application Date August 24, 1932 Publication Date February 16, 1933 Assignee Edwin Ivor Morgan
Paul Sison Ham
Edgar Henry Bence IPC F16K 31/44
F16K 31/53 

Edited December 24, 2023 by Ray T

[Derek R.]

'Shock' absorbers and dampers often get mixed up, though the type of shock telescopic absorber as show also incorporates a damper in the centre section which more often than not contains a reservoir of oil; calibrated holes through which a piston forces the oil through (creating a damping effect) and sometimes valves which may allow freer movement in one direction than the other. Some dampers can be friction pads in disc or linear format, tightly held by strong springs compressing the disc, some of which are adjustable, some set at the factory during construction. In such a type, oil is not their friend.

 

A rubber pad is also a shock absorber, but of a more simple type. Item No.38 in the drawing would most likely be the position of any rubber pad.

 

I've always liked the Ham Baker gear. The positioning of the paddles and their size, makes for fast emptying and filling. If you pull them 'right' when ascending, the boat will hug the side wall nicely. I've almost always 'dropped' them by knocking the jaws off the spindle whilst controlling the drop with a firm grip on the spindle. You will need tough hands for that though. A few won't drop, so wind 'em down.

Edited December 24, 2023 by Derek R.

[magnetman]

Yes they are fast. 

I like the clicking of ratchets too much.