Monday, November 02, 2009

Topping it off

When we left last time, it seemed that all I had to do was put the ply trackbed on and that would be it. Well, in the words of the bard,The best laid schemes o' mice and men gan aft agley' and mine definitely have gan aft agley today.

I realized this morning that the unsupported spans were probably going to sag, and on consulting Barry Normans book again discovered that my raised bits should probably have run the length of the modules, rather than across like I have done. Just as well it wasn't terminal and all I needed to do was make some more beams that spanned the gaps, and then I could just screw the track base down to them. So, back out to the garage and more gluing, nailing and cutting in store. A few hours work later and I think I'm finally done with this bit.

Still, if I want it to last a few years (ie more than about 5) I may as well make a decent job of it now. the trackbed was then screwed on top, to finally finish things up

The surprising thing is that even with all the extra engineering stuff, the all up weight is only about 4-5 Kg, which is manageable by one person fairly easily.


beaka said...

quite impressed with this method of construction. as you say its very light and should prove to be reasonably strong and durable. have you ever thought of getting into the homebuilt aircraft hobby? would be able to fly to venues in your plane, then dismantle it and set up wings etc as your modular layout. A La fixed wing motorised Dandruff.

woodsworks said...

Very neat and tidy work, and as Beaka suggests, a good example of how wooden aircraft are built. Mucho rigidio can be gained by adding diagonal braces - by doing this, the improvement to the frame's rigidity is often such that you can reduce the number of cross-members and so not increase weight significantly. Aircraft use the outside skin to achieve this, but in your case, ply strips criss-crossed inside two or three 'bays' would do the same.

Motorised Dandruff said...

Screwing the plywood trackbed onto the frames has also had the same effect (its not going anywhere at all). I'm not sure how adding diagonal bracing would have saved me any weight as I still would have had to come up with some way of raising the trackbed up off the baseboard, which would have been far harder if there was diagonal bracing.
More importantly, I think anyone with access to a saw bench can do this reasonably easily, and its almost indestructable.