Crinan

[Signaller69]

The swing bridge has been giving me headaches for some time. Although the mechanism seems to work ok, during opening and closing it tends to catch and be a little jerky. I put this down to 2 issues; firstly the weight is not balanced about the pivot point, mainly due to this being just over a quarter of the way along the deck. Although I have added a fair amount of weight at the short end it still wasn't enough. Not having any more space under the decking I opted to fill the rear girder sections with "liquid lead" shot secured with PVA. As these sections are plated over anyway this will not be visible once the new "plates" are added. The centre of gravity is still about half an inch ahead of the pivot but it is a big improvement.

The second problem was the track power which was hard wired through a hole in the bridge support, causing further drag due to the wires. This has been rectified by fitting old Trix coach lighting wiper contacts under the deck which will contact on nickle silver plates to be fitted to the base. Once the components are painted I hope there will be no visible sign of wires etc.

 

If the bridge is still jerky I have another mechanism to try but will try the existing one first.

[Signaller69]

Although I have not posted much lately, work is progressing. I'm pleased to say the swing bridge now functions much better, still not quite as smooth as I would like, possibly due to a minor tight spot in the mechanism, but it does open and close properly without catching now. The corresponding locking mechanism of sliding square rod (see first pic below) has also been beefed up with a thicker wire actuating rod through the baseboard for reliability; just needs a cosmetic cover over it now. Other work is mainly centred on wiring alterations, although a little more detailing work is ongoing around the canal lock area.

 

I took the opportunity of taking some more phone snaps!

Is the Seagull on the pole about to leave a "deposit" on the car outside the hotel? Or is he hoping for a free meal courtesy of a departing Fishing boat?

 

The "Lucky XI" leaves the Canal into the Sea Loch.

 

Looks like the Fork Lift driver is on his lunch break. . .

 

A solitary Engineers wagon on the fueling point; must need a spot of attention.

 

The old turntable well is gradually returning to nature.

 

[Andrew P]

Being a lover of Scottish Layouts, (Glen Roy and Glenfinick), I have to say your Lock and Bridge scene above is stunning, well done.

[Signaller69]

Being a lover of Scottish Layouts, (Glen Roy and Glenfinick), I have to say your Lock and Bridge scene above is stunning, well done.

Many thanks Andy, much appreciated! I really must dust the canal!

Edited January 23, 2018 by Signaller69

[Waverley West]

Lovely, Martyn. Just oozing with atmosphere.

 

Dave

[Bustered]

Martyn, the layout looks excellent, a real beauty!

Best wishes

Nige

[Max Legroom]

Looks fabulous but I'm a bit worried about the individual on the quayside in the picture with the fish vans!

[Andrew P]

Looks fabulous but I'm a bit worried about the individual on the quayside in the picture with the fish vans!

PURE Highland Malt no doubt.

[Signaller69]

PURE Highland Malt no doubt.

He had done the Distillery tour possibly, the "Glen Crinan" going down rather too easily. . . https://www.whiskyauctioneer.com/lot/43060/glen-crinan-pure-highland-malt

 

He will be assisted into an upright position shortly. . .

Edited January 24, 2018 by Signaller69

[EnglishElectricFan]

Hi Martyn

Looking very good. Love the head on shot of the two locos in the station. You can almost hear them ticking over!

Regards

Simon

[Shadow]

Looks fabulous but I'm a bit worried about the individual on the quayside in the picture with the fish vans!

I'm more worried about the size of the mice outside the wayside hut!!

Edited January 26, 2018 by Shadow

[Signaller69]

I'm more worried about the size of the mice outside the wayside but!!

Ha, I see what you did there!

[Signaller69]

Having built the Canal Lock extension I have now had to extend the lighting facia, these are of fairly simple construction using a frame of 20mm square strip and hardboard, with clip fit strip lights. Originally these were arranged in 3 equal lengths with hinges so that the whole thing folded into a flat Z shape for transport, with bolts to keep the unit rigid when in place on the layout; this has now been revised to 2 folding pairs, supported in the middle by an inverted L shape support. A productive afternoon was spent at the Clubrooms erecting the modified structure and doing some odd bits of paintwork.

 

Messed around with my phone trying to get some low angle shots too.

[Nick G]

Looking good Martyn.

[Signaller69]

Looking good Martyn.

Thanks Nick.

[luckymucklebackit]

Smashing Detail Martyn, couple of the figures look as though they are straight out of the knitting pattern covers of the day, maybe there was a shoot on

 

Jim

[brylonscamel]

Having built the Canal Lock extension I have now had to extend the lighting facia, these are of fairly simple construction using a frame of 20mm square strip and hardboard, with clip fit strip lights. Originally these were arranged in 3 equal lengths with hinges so that the whole thing folded into a flat Z shape for transport, with bolts to keep the unit rigid when in place on the layout; this has now been revised to 2 folding pairs, supported in the middle by an inverted L shape support. A productive afternoon was spent at the Clubrooms erecting the modified structure and doing some odd bits of paintwork.

IMG_20180131_161738_1.jpgIMG_20180131_161703_1.jpg

 

Messed around with my phone trying to get some low angle shots too.

 

This set of photos are great - what a wonderful series of scenes and you really feel like you're part of a sunny waterside atmosphere. The bridge view is spot on!

[EnglishElectricFan]

Having built the Canal Lock extension I have now had to extend the lighting facia, these are of fairly simple construction using a frame of 20mm square strip and hardboard, with clip fit strip lights. Originally these were arranged in 3 equal lengths with hinges so that the whole thing folded into a flat Z shape for transport, with bolts to keep the unit rigid when in place on the layout; this has now been revised to 2 folding pairs, supported in the middle by an inverted L shape support. A productive afternoon was spent at the Clubrooms erecting the modified structure and doing some odd bits of paintwork.

IMG_20180131_161738_1.jpgIMG_20180131_161703_1.jpg

 

Messed around with my phone trying to get some low angle shots too.

Love the photo of the VW Beetle and Morris Minor traveller Martyn. If you took 'Ken' out of the picture you would think it was real !

[Signaller69]

Smashing Detail Martyn, couple of the figures look as though they are straight out of the knitting pattern covers of the day, maybe there was a shoot on

 

Jim

 

All I can say Jim is it must have been the subconscious knitting pattern viewing coming to the fore when I had the paints out!

 

Love the photo of the VW Beetle and Morris Minor traveller Martyn. If you took 'Ken' out of the picture you would think it was real !

Ken? Could be Simon, There is a scantily clad Barbie awaiting painting, but that might be too much for some folk on the forum. . .

 

 

Talking of figures (people, not waistlines) I was looking at a photo of a group of ferry passengers leaving the station at KoL in Summer 1970 in a book, every single bloke was wearing a shirt, about half with a tie, some with pullovers or jackets (not a t-shirt in sight) so I may have to find some more suitable figures!

Edited February 1, 2018 by Signaller69

[Signaller69]

This set of photos are great - what a wonderful series of scenes and you really feel like you're part of a sunny waterside atmosphere. The bridge view is spot on!

Many thanks for the kind words, glad you liked the pics!

[SHerr]

Wonderful evocative layout that just keeps getting better.

 

I absolutely love the swing bridge details, particulariliy the rodding/end bolts etc. I have to say I wouldn't worry about the bridge jerking, catching or not aligning. Having tried to fix a few real ones I can assure you its nothing but prototypical! 

[Signaller69]

Wonderful evocative layout that just keeps getting better.

 

I absolutely love the swing bridge details, particulariliy the rodding/end bolts etc. I have to say I wouldn't worry about the bridge jerking, catching or not aligning. Having tried to fix a few real ones I can assure you its nothing but prototypical!

Many thanks! I'm loathe to fiddle with the bridge mechanism too much to be truthful, its taken me 2 years to get it to work reliably so far!

[lezz01]

Hi there Martyn.

This is a great model mate.

With regard to the swing bridge issues. Is the grey disc at the top of the spindle the bearing surface? If so I would either make it larger or better still use a ball race the same diameter and glue one half of the bareing to the deck and one to the plinth that the bridge sits on and pack it with a light grease. You also need to get the point of balance exactly on the pivot. Close isn't good enough mate. They had this issue with the mid-upper turret of both the avro manchester mk 3 (Lancaster) and the short sunderland. It's was asymmetrical and because of this the center of gravity was off center  and it suffered from jamming which is why they changed it to a symmetrical design. 

Regards Lez.Z.      

[Signaller69]

Hi there Martyn.

This is a great model mate.

With regard to the swing bridge issues. Is the grey disc at the top of the spindle the bearing surface? If so I would either make it larger or better still use a ball race the same diameter and glue one half of the bareing to the deck and one to the plinth that the bridge sits on and pack it with a light grease. You also need to get the point of balance exactly on the pivot. Close isn't good enough mate. They had this issue with the mid-upper turret of both the avro manchester mk 3 (Lancaster) and the short sunderland. It's was asymmetrical and because of this the center of gravity was off center and it suffered from jamming which is why they changed it to a symmetrical design.

Regards Lez.Z.

Hi Lez,

Thanks for your comments.

 

The discs under the bridge don't take any weight, the deck actually sits on the drive shaft which does indeed sit in 2 ball races around the shaft to hold it true laterally, with gravity minimizing any vertical play. The gearbox is a multi ratio affair and I think the slight catching is actually a tight spot in the gear train with a gear being a fraction out of true. Although it has hardly had any use since re-configuring so it could just need running in. As the deck is held onto the shaft by a small screw, next time I remove it I will run the motor for a while in each direction to see if it improves matters.

 

The weight added recently has helped reduce lateral forces on the drive shaft, as well as ensuring the locking bar locates correctly. But without ripping up track and decking it is hard to see where I could fit any more weight either above or under the deck as clearances are tight so until I've given the mechanism a fair chance to bed in I think I will leave well alone, as it works well barring the slight tight spot.

 

Martyn.

[lezz01]

Hi there Martyn.

Firstly let me say that your layout is so convincing that I spent about an hour on the interweb searching for images of the railway at Crinan. It wasn’t until I reread your thread from page 1 that I realised that it was freelance and that although there is a swing bridge there in real life it’s the one at Benavie that your bridge is based on.

                                                             Now then having read your description of the bridge and mechanism in your reply to my post I can see where you have gone awry with this. There are two problems with this and no matter how much you fettle the mechanism it will not run properly, it may run better but it will not fix the issue. The biggest problem is the point of balance and the fact that it is bearing on the pivot and not on a proper bearing. The pivot is providing a very small surface area and the two ball races you describe the pivot shaft running in are not doing what you think they are. They are not supporting the deck in any way; all they are doing is allowing the shaft run freely on its axis. The fact that the balance point is not exactly on the centre of the pivot is inducing a lateral force which is causing the pivot shaft to flex and is forcing the ball race into the side of the bearing cup and although the force isn’t very great it will cause what appears to be a tight spot in the drive chain.

                                                           The best analogy for this is the use of a worm and worm gear with grub screws in a loco drive. People will spend many hours building a loco chassis that runs like silk without a motor fitted and when they fit a motor to the gear box the chassis will run fine one way and be jerky the other or poorly in both directions they then spend hours and hours fettling the chassis again and again to try and fix the tight spot or running the motor back and forth to run it in when the problem is not caused by anything on the chassis or wheels or the coupling rods. The problem lies not in the parts they have fettled but with the fact that when the grub screws are tightened on the worm and worm gear they are both pushing the gears off centre because the hole in both of the gears are larger than the motor shaft and axle. The answer is to file a flat on the axle and motor shaft and only do up the screw until it just touches and add a spot of glue so it doesn’t move this will allow a little backlash but the tight spot will disappear.

                                                           Now to get the bridge to run properly you have to get the balance point in line with the centre of the pivot and give the bridge a proper bearing that actually takes the weight of the bridge. This is not a big problem and has two fairly simple solutions.

#1: add more weight to the short end of the bridge. Now I know you have run out of room for more weight but there is something you can do about it that you may not have thought of. The curved segment at the end of the deck next to the weight you have added can be made of metal could it not? Also there is space between the weights and the curved section that could be filled with “liquid lead” which will give you a few more grams that end. There is also space beneath the rails that have blobs of glue in at present that could also be treated the same way.

#2: reduce the weight at the long end of bridge. You can do this by using a dental burr or milling bit in a mini drill to gouge out some of the underside of the deck a bit at a time until you get the balance perfect without having to touch the top side of the deck.

There is a third option but it involves a partial rebuild of the bridge deck and it would give you lots of voids in which to install more weight that would be totally unseen.

                                                             Once you get the balance right you can install a tapered roller bearing around the pivot to take the weight of the bridge and you will have no weight on the pivot at all. Now as it happens I came across just the thing you need on fleebay with the following dimensions ID 25mm OD 47mm H 10mm for less than a tenner.

I hope that you find this useful.

With kind regards Lez.Z.