Level Crossing Operating Mechanisms

It's not my money I'm spending here 8^)

In message , Chris writes

The crossing gates that still operate quite happily on the NVR at the platform end of Wansford station are paired gates that open as mentioned above and move together - all four move together quite precisely. Well at least they did until a wagon was fly shunted through them a week or so ago thus involving some 'adjustment' to get them closing correctly again.

The gates don't hesitate or jerk while opening and are quite smooth in operation as they have damn great revolving base plates beneath each gatepost. The signal box is on the crossing side some sixty feet away. The gates are operated by a rather large wheel - similar to a ships wheel, located at the end of the lever frame and at the roadside end of the signal box. If anyone wants detailed photographs I can easily throw some up the line or put them on the website.

To motorise and match four gates on the layout is quite easy if a pair of servos such as we use in model boating are located under the baseboard and a single DP switch is used to feed the twin units, which usually come with both disk and offset arm linkages, need very little modification, [ if any] and are available quite cheaply from Howes [among others]. We are currently building a similar set up into our OO-Gauge Hammerton Junction layout which is resident in the NVR carriage on platform three.

Cheers.

I've got an idea that somewhere I saw a photo of crossing gates that rose vertically, like a guillotine, obviously only blocking the road and not the railway. Perhaps somewhere on an industrial line? In Japan, vertically rising gates can still occasionally be seen, these are often nothing more than a couple of wire cables across the road, liberally decorated with yellow flags. Some seen were on busy suburban lines. Regards, Bill.

Ah, my childhood haunts. Is that beautiful lattice footbridge still around at Havant level crossing, just before the line runs off up to Lunnon?

I do recall, though, that the gates at Southborne didn't *quite* start off at the same time - there was lag in the system, and one would get to about 10 or 15 degrees before the other suddenly kicked in abruptly and caught up quickly. It was quite pleasant to watch.

R.

Well, it's certainly a problem to sink your teeth into.

R.

Probably wear on on the cranks. Last time I went through Havant, June this year the footbridge was still there. I don't know if the signal box at Havant will be demolished when the recently announced resignalling is commissioned together with the signal box at Petersfield. It was kind of strange looking at fish tank relays, so named for their size and similarity to fish tanks, with manufacture dates in the 1920's. Although overhauled in the interim, probably still there now in the locking room/relay room below the operating floor at Havant.

Chris

I'm going to try to explain this without the use of diagrams (and no safety net folks!)

Imagine a four gated level crossing, 4mm/foot scale.

Each of the swinging wooden gates is firmly attached to a steel pin which locates in a bearing at the top of the gate post and goes through a bearing at the bottom of the gate post and then through a hole in the baseboard.

Underneath the baseboard it makes a 90 degree turn to parallel the direction of the gate itself. at the end of the steel pin there is a vertical curve which locates in a slot in a disc.

The disc looks like a 7 inch 45rpm record Could even be one with four slots cut from the outside edge towards the centre, curved ones would be nice, but straight ones would do. As the disc rotates... on an old record turntable, even, the ends of the steel pins would be forced to follow the slots... rotate one way for closing, the other way for opening. You could vary the slots to make it look like an invisible signalman was closing them individually. You probably would need to move the platten by hand, even 33 rpm would be too fast, since we are dealing with 1/4 turn here. some sort of motor could be rigged up. The major attraction woould be **recycling junk** i.e. it's cheap.

David

Thank you to everyone who has posted. The level crossing will have swinging gates, not lifting barriers. Since the track is a single line it is most likely that we will use two gates instead of four half gates.

Thanks in particular to Roy for suggesting the model boat servos, which we are looking into.

Regards,

Archie

With two gates, one will have to swing before the other, or they will hit if both swing together. Regards, Bill.