Sector plate - warping

[Milano]

Folks

 

I have recently made a 12" long sector plate (00 gauge) from 5mm plywood and glue the track in place however tonight I have found that it has started to warp in the middle. Is this fixable or do I just start again?

 

Milano

[DCB]

There is ply and ply.  You want the top quality stuff, as used in good old kiddies toys not the joke stuff from B and Q and the like,  Laminate flooring offcuts are good, less likely to warp if you glue track to them and readily available in skips or even in B&Q.

 

Sector plates and turntables need good solid track bases and good solid supports, I would start again, maybe aluminium strip would be a better medium. 

Then again I wouldn't glue the track in place, the track will expand and contract so I like to solder the rails to brackets secured at the ends of sector plates, expansion being taken up by a rail break and fishplates at the mid point.

I used a bit of square section trunking for a hidden turntable deck, no sign of that warping yet after 30 years or so.  

[bike2steam]

I always made my sector plates ( 3 & 4 foot long) out of 9mm thick ply with a piece of '2-by-1' along each side on the top, rigid, and summat to grab hold of when you move it.

Edited June 25, 2018 by bike2steam

[PaulRhB]

You could add 15-20mm aluminium angle on the edges if there's sufficient width. Countersink in 4 small nut & bolts each side. With ply it really needs to be sealed to prevent moisture causing the warping especially if unbraced, 3 thin coats of gloss paint is usually good to seal it long term.

[johnb]

A single thinnish sheet of almost any wood has the probability that it will warp at some point. Even indoors the summer/winter change in humidity can cause warping.

I've even had good quality 9mm birch ply move slightly, only 1mm or so, but that was enough to cause problems.

My sector plate is 4ft x 1ft (1200 x 300 for the converted!), braced with 6mm ply 75mm high, pinned and glued to the edge and hasn't distorted.

 

John

[doilum]

Assuming that it would be difficult to go thicker than 5mm, stores like b&q sell aluminium strip in 50mm widths. This can be glued to a 75 or 100mm strip of thin ply to attach any side rails. A visit to a metal recycler might produce the metal for free. Likewise, upvc window manufacturers may have offcuts of channel section. The expensive way is to solder rail to a single sheet of coper clad paxolin or circuit board.

Finally, some O Gauge modellers have adopted flat bottomed plastic guttering for use as fiddle yard cassettes. This would be perfect and maybe free from a skip near you.

[timbowilts]

Another option is to actually use aluminium angle for the rails! This will definitely prevent the sector plate or turntable from warping

 

Tim T

[Milano]

Thanks all for your input and advice. I have been given some 5mm think plastic sheet that I may try and use.

 

Milano