Slide out section positive track alignment.

[RAF96]

Removable section track alignment.
I have a hefty slide out section, due to weight and track geometry being unsuitable for a lifting or hinged section. The images shows there are twin tracks on bridges at two levels. Rail alignment is currently by copper-clad sleepers and reliant upon the bridges not moving relative to each other.







Electrical connect is by way of plug together choc-blox which provide some firm alignment added to by lever over clamps.

My problem is the drawer can move a tad resulting in one or more 'corners' being misaligned enough for a derail. There is no way to use dowels as positive locators, nor loose hinge pins, etc. I would like to use those Micro-Tech keyed rail end locators but the slide out method makes that unlikely.

Any ideas from the collective mind are welcomed.

[Tricky Dicky]

Most people use things like sliding bolts on sector plates for alignment which is something similar to what you want.

https://www.screwfix.com/p/straight-doo ... 76mm/74947

Could you mount a couple of these somewhere handy but out of sight when viewing from the scenic side?

Richard

[Steve M]

I have found sliding door bolts to allow a bit too much play to give totally reliable location (may also be down to my carpentry!).
I now use small overcentre latches for all my board joints, fixed or removable. The tension can be adjusted to give a really firm joint which is strong enough to stop my lift out section from moving even without dowels or pins.

[Tricky Dicky]

I have found sliding door bolts to allow a bit too much play to give totally reliable location (may also be down to my carpentry!).
I now use small overcentre latches for all my board joints, fixed or removable. The tension can be adjusted to give a really firm joint which is strong enough to stop my lift out section from moving even without dowels or pins.

I do not think any method is 100% But the nearer you get the better. An exhibition layout I helped on had overcentre latches and it was still possible to misalign boards, it comes down to quality in the end and how much play is in the moving parts. Pressed steel sliding bolts are hopeless but the type I linked to I find are pretty good at keeping things in line Using dowels of some sort ie. Pattern makers dowels where you have two metal components to eliminate wear are the best way to go but with the OPs requirement to slide his bridge section in place rather than dropping it place I cannot readily see how he can incorporate dowels effectively.

Richard

[cadman]

Rob, these door catches might help to keep the sides tight. Just using the rollers front and back of each section should keep alignment and fill the gaps.

[RAF96]

All good suggestions...
The layout is a U shape with 2 main boards 12 ft x3 ft, joined at the far end by a bolted in 3 ft drop valley. This means the slide in section open end has a bit of flex, maybe enough to allow engagement of some positive locators, which then clamp tight using over centre adjustable toggle clamps.
I had wondered about if there was enough slack for these -



The problem remains in getting 4 sets of tracks at different levels to align.

Another bright idea was to arrange a drop in guard rail section at each joint, with 4 pins that engage in the track bed, much like the inner rails on a point or crossover.

[Tricky Dicky]

All good suggestions...
The layout is a U shape with 2 main boards 12 ft x3 ft, joined at the far end by a bolted in 3 ft drop valley. This means the slide in section open end has a bit of flex, maybe enough to allow engagement of some positive locators, which then clamp tight using over centre adjustable toggle clamps.
I had wondered about if there was enough slack for these -



The problem remains in getting 4 sets of tracks at different levels to align.

Another bright idea was to arrange a drop in guard rail section at each joint, with 4 pins that engage in the track bed, much like the inner rails on a point or crossover.

As I said before pattern makers dowels are the most effective at alignment of baseboards. DCC Concepts make a version that is probably the easiest to install but at a price.

https://www.dccconcepts.com/product/bas ... ls-4-pack/

You can get a pack with all the necessary drills but if you have them then it is more cost effective to get the pack of 4 without the drills.

The issue for you is the requirement to slide your section in because from my view of the removable section the dowels would need to fit in the slide section bearers so it would have to be dropped in rather than slid in. Your other issue is ideally you should have arranged any location dowels before track laying so it may mean relaying the track and using solder on sleepers should ensure alignment at the joins. Once aligned on the dowels using overcentre latches will help pull the the two fixed layout sections in tight and stop any movement.

Richard

[Tricky Dicky]

As an after thought. Would it be possible to use some loose spacers on the bearers just to get over the dowels and once having the slide in section positioned pull out the loose spacers allowing the section to drop the last few millimetres onto the dowels? The loose spacers would only need to be slightly thicker than the dowel protrusion.

Richard

[RAF96]

Quote - Your other issue is ideally you should have arranged any location dowels before track laying

I did, by way of the electrical connectors at the back with stop blocks which locate the back edge, shims under the runners to give vertical alignment and toggle clamps at the front to secure it all. The problem is the main layout being a big U shape is prone to slight movement, thus any slight misalignment at either end of any of the 4 tracks can result in a derail.

I could use dowels in the sides rather than the bottom as the carry structure for the tracks is 18mm ply installed at high and low track level which ensure a good snug fit when clamped. I just need enough sideways slack when unclamped to allow the section to slide in.

[Tricky Dicky]

Number of bolts going into T-nuts in the sides would help with alignment and pulling the layout together. The only issue with that is bolts going through wood will tend to wear the holes and start allowing unwanted movement. A way to get round that is to line the bolt holes with metal tubing but you would have to ensure the bolt passing though the tube would need to be a snug fit otherwise you will still get some movement.

Richard