Kind of lost my Mojo (an MTV Zander)

I haven't spoken of this one in public, well, not the chassis anyway. This was to be one of my big challenges away from "boxes" of signal boxes and try something a little different.

As I have a liking for the sand trains due to my work on the Churnet where they used to operate I decided to look at what had run before the PAA wagons I had done. To that end, one of the first i came across was the MTV/Zander wagon, built of redundant TTA taker chassis in the 1970's.

My initial thoughts (and research) showed that the TTA had been originally done by Airfix as one of its kits (later Dapol) so I acquired one of these kits of ebay for around £8 and started drawing the top body, only then to notice that the chassis in the kit contained 2 large ribs to support the tank which would have to be cut off.

Didn't really want to do that....

So I set to with the ruler and micrometre and started to copy the Airfix chassis design and draw up a replacement..

I feel I made good progress, but then I lost my mojo when I came to the brake rigging. I had planned to go with a friend to see the sole surviving example at the Battlefield line railway, but then covid struck. I also found that I was looking at an injection moulding that was probably older than me and starting to show its age in detail, So I wanted to make something a little more 21st century.. but then interest waned.


So here is where we are at so far. Most of its done bar the brake gear.


Quite pleased with the detail, no idea how it will come out though.


And finally with the top on.

anyone got any plans of similar brake rigging ? cant see on photos close enough to work it all out.

Its done in 123D design, so probably limited by who can help on this unless I export as a different file type, but I'm willing to share this model with others in return for a little help.

Andy

PS. The Airfix kit is also still unbuilt!

 

I decided to go off on a limb and asked on a wagon group on Facebook if anyone had any photos..

unbelievably one of the preserved ones was being moved this morning to Brechin in Scotland to its new home. Very kindly the owner has sent me some great photos which will help me draw up what I need.

 

Thought I’d give what I have got so far a go on the printer..

as can be seen, the chassis seems to have come out ok, but I opted to tilt the body, normally I print square, and on this occasion the initial picture appears to show layer lines.. it’s still draining at the moment so not sure if this is down to too thin a wall or vaccuming against the FEP. what’s not visible are the buffers and the axle boxes printed separately.

more tomorrow..

Andy

 

Well the good news is I’m refunding my mojo.

I’ve not finished drawing yet, but in true Dundee fashion, I’ve made a start in printing.

upside is.. it works, although I think I’ll make a small design change. I’ve also somehow managed to use an older version of the top where the ribs don’t match the chassis

now to see if a wheel set fits or if I’ve totally got it wrong.

here is one of the four spring and axle box sections. Not been cleaned up yet.
Also trialled buffers, but two broke and stuck to the FEP.. another strip and clean!

 

Yes. I have. Maybe the next “wagon” project. Subject to finding drawings.. infact it could be a Platform 1 project. Maybe even multiple artists?

 

So V2 was printed a little different. I have decided to combine the chassis with the body, which gives it strength and well, just makes some of the panel lines better..

I opted for a change to my usual printing method, as I’ve explained else where, boxes when printed (especially if sealed ie having 5 sides) can cause a pumping effect like putting a glass in a sink of water and lifting it where it keeps the water in till you lift it out the water… well the same happens with resin when printing - sometimes it’s not enough to lift it out the resin, sometimes it is, but you risk trapping air in that box and with the soft uncured printing, compressing air inside can cause it to distort.

so, the common answer is to orientate it so there is no trapping- this is also something that Paul L has discussed on his Scottish loco thread.
Orientation one, where the scaffold connected to the bottom of the chassis leaving the top on display area crisp.

and here is the orientation the other way where the scaffold goes to the too surfaces and inside the wagon..

as you can guess, for neatness and visibility, it’s a no brainier which I will choose in future.

just so I can use them, I’ve also printed some more axle boxes.

That’s as far as the physical model has progressed as I’ve had a small issue with actually fitting wheelsets.

this will be addressed in the next print to stop the axle boxes flaring outwards to fit a pair of OO axles…. Which begs one question.. have I gone wrong somewhere as there is no way I could fit a set of 18.83 axles if ever wanted???

andy

 

I’ve returned to the desk top to try and progress from the stalled section now I have some photo reference. I’m lacking dimensions, so some is pure guess work and to look.. not my usual approach, but if I can get it somewhere near, it’s easier to then correct later if/when I get the size of the parts I need.. however, I also have to be super realistic that in 4mm some parts scale down to something that is just too small or too fragile to actually print or model (although dick head here spent half an hour the other night drawing a 4mm split pin to then think why??? But it does look good on the model! )

anyway, on to some screen shots..

Ive split the model down for working on it. Top, chassis, axles and brake gear.


This is the vacuum cylinders and the half done axles and brake rigging. Still have the second brake handle on the outside to model but this has a reverse lever on it and also a slide (to allow for if the brakes are already on by the vac or not when applying the hand brake - I’ll explain in a later post)

combining the model to show some
Progress.


And as it all stands at the moment..

for my first wagon… I’m rather pleased so far!

andy

 

I haven’t yet decided to be fair..

I’ll finish drawing it then work
It out.
Andy