Basic baseboard question

[Richard Westcott]

Hello Everyone,
I am new to railway modelling and I am about to build my first baseboard which will be used on a table top.
The base board itself is going to be made out of 12mm MDF and I intend to sit that on a 2x1 frame. I want to used powered points on my track and I was wondering if a 1 inch gap underneath the baseboard would be sufficient?
Thanks
Richard

[Hobby]

I'm not a fan of mdf, it's heavy and difficult to work and if you are drilling it the dust is not very healthy. Chipboard is an alternative but I suspect most of us use ply, 9mm should be OK.

To answer the question on point motors we need to know what make you'll be using!

[Richard Westcott]

vTo answer the question on point motors we need to know what make you'll be using!

Hello Blair,
Thanks for your reply, I have not decided what I will be using yet, what would be the maximum amount of space I will need to allow for?

I understand your point on MDF, I haven't bought the any materials yet so I can always switch to ply.

Many thanks

Richard

[Hobby]

If you are buying new I think you'll find the point motor makers will give tge dimensions on their website. As every one is different it's an impossible question to answer. I woukd add that in addition to the depth I'd add on 10mm as protection against them being hit whilst moving the board around.

[Ian McAulay]

First thought: If you're using 2x1 framing, it should really be set with the 2" dimension as the vertical one as this will produce a much stiffer result. However remember that if you're using planed square edged timber, the actual depth is only about 44mm. You will get even more rigidity without adding weight by going for deeper but thinner material, say 70x15mm (exact sizes available depend who you but it from).

Second thought: 12mm MDF (actually 12mm anything) makes for a very heavy baseboard and doesn't really contribute much to the rigidity of the finished baseboard. (And MDF dust is nasty stuff as Blair points out.) I'm slightly unorthodox in favouring very thin baseboard tops and generally go for 4mm ply. Provided the framing is at least every 300mm (1 foot in old money), that's plenty strong enough. It's thin enough to drill wiring holes with a bradawl or a bit in a pin chuck. For awkward shapes, it's also thin enough to cut with a Stanley knife. Some say it leads to a very noisy baseboard but with cork (or roadbed of your choice) under the track and scenery in place, I've never had problems.

One other point: Having diagonals in the baseboard framing vastly improves the torsional stiffness of the baseboard.

Back to the original question. It all depends on the make of point motor.

The shallowest (and cheapest) are probably SEEP solenoid motors, with a depth of about 12mm. One disadvantage of a thin baseboard top is that you don't have much to screw point motors to. Gluing a pad of 4mm ply in place first then screwing to that solves the problem but increases the depth to 16mm. These are the ones I am using on my current 009 project.

Peco PL-10 or PL-11 solenoid motors are popular. You can attach them directly to the bottom of Peco track, but they require a huge hole in the baseboard which is difficult to ballast over. They aren't really designed to be attached to the underside of the baseboard but Peco offer an adaptor base for that. With the base, the overall depth of the motor is about 13mm. However, if you need to add the optional microswitch for frog polarising, that will add more to the depth (not sure how much, maybe 5mm) and also make the whole thing very expensive.

On my 00 layout, I use DCC Concepts' Cobalt Omega Classic motors. They are slow acting and generally gorgeous but expensive (£17.95) and huge at about 75mm depth (fortunately I have 100mm clear depth under the board on that layout). They also require slightly unusual wiring.

I don't have experience of the new Peco Twist-Lock motors or of servo motors, which might be options to consider.

Another disclaimer - my preference for very thin baseboard tops is something of a minority view. Other Society members may well disagree with this (possibly emphatically). (For my own current 009 project, I've gone completely off-piste with a baseboard made entirely of foamcore board.)

That's a much longer reply than I set out to give! I hope it's useful.

Ian

[Hobby]

I tend to use 6mm ply for the top, Ian, as I think do many others, weight wise I doubt there's much in it. Having said that I only have a top surface for trackbed, buildings and roads, the rest is cut away. As you say the main thing is bracing, but dependant on the wood used that can also add weight...

9mm ply 4" deep for the outsides, 6mm for the bracing and 6mm for the top is my usual way... No problems with point motor depth, though I don't usually use them.

You'll get as many ways of baseboard construction as members, Richard!

[Richard Westcott]

Thanks Blair & Ian,
I am grateful for your advice especially on the point motors.
MDF is off the list and I will go for plywood.
All the best
Richard

[Tom Haythornthwaite]

Will you need to transport it anywhere?

I'm happy with my 10 mm plywood but then it's for a permanent layout.

[Richard Westcott]

Will you need to transport it anywhere?

Hello Tom,

It's going to be an L shaped baseboard in 3 sections, I was going bolt each section together so I move it around.

All the best

Richard

[Hugh Norwood]

Not wishing to muddy the waters, but Angst's baseboards are made of two layers of 5mm foamboard laminated together with a frame of 54x12mm hardwood. Point motors (SEEP) are mounted underneath on plinths made of offcuts of the framing wood (fortunately, SEEPS have long actuating wires).

[Graeme Dunbar]

I've used 6 mm MDF (never again - though for a permanent layout weight is not such an issue) and 6 mm (actually a bit less) plywood. It is much lighter.

I'm also convinced of the merit of taller and thinner frame pieces than the traditional 2x1. I half jokingly wonder if a 2x1 frame is stopping the top from sagging or if it is the other way round.

Thickness may add strength but that is rarely needed, but height adds stiffness and baseboards are rarely too stiff. Possibly the main reason for any thickness in the side frames is to stop them twisting and buckling. To this end some baseboard builders make the frames as box girders using two planks of thin ply separated and held together by small strips of wood top and bottom, say 10 mm to 20 mm square, depending on baseboard size. But that is starting to get into serious carpentry.

I simply sandwiched two 6 mm thick pieces of ply for the frames and got a 1200 mm x 600 mm baseboard with low backscene out of two sheets.

[Richard Westcott]

Thanks Hugh and Graeme for your help, I have decided on a plywood base with a 3x1 inch frame. I live in the far north of Scotland and can get these materials locally, having anything delivered costs a fortune!

All the best

Richard

[Hugh Norwood]

I am on record as saying that if I ever stared another layout, I'd but one (or more) of those flat-pack laser-cut ones.

BUT

I couldn't find one (or a combination of more than one) that suited the size I wanted, so I've gone and built another using the same methods! (sucker for punishment)

[Colin Rainsbury]

Hi Hugh

I am taken with the ones that Tim Horn produces, however, there is now a waiting list and currently at 15th Nov 2021, his website is down. The good news is if you let him know the exact sizes of the boards you want he will make it for you as a flat pack kit, currently you can contact him via his Facebook page but he is trying to get a new website up and running as his old one was taken down by the provider, for reasons I don't know.

Hope this helps.

Colin

[Hobby]

G&H also can do sizes to suit you, not just their standard sizes (Hugh!).