Soviet Trench Digger Diorama/Base Question

[Dave Ward]

I've had this in the stash for a while ( I got it off John in a Trumpeter Sale........) and I've been pondering on how best to display it.

For it in action:

The easiest way would be in travel configuration, with the digging wheel raised, but I don't think that really cuts it. It really should be shown actually digging a trench.
The BTM-3 is based on a T-54 chassis, reversed, so the drive sprocket is at the front - the length is stated as 7.4m, although, I reckon that's with the wheel stowed. 3.2m wide. It can dig a trench 1.5m deep, by 1.0m wide.
In 1/35, that's 210+mm long,91mm wide, trench 43mm deep x 28 wide.
My doubts are about the size of the base - I reckon, it would have to be about 2.25 times the length of the Chassis = 470mm long. Wide, in order to take in the spoil thrown out on either side 3 times the width of the vehicle = 275mm, and the depth of 43mm +10mm= 53mm.
So, I have to have a base that is 470mm long x 275mm wide x 53mm deep, with a 43mm deep x 28mm wide slot running about 150mm in from one end.
Has anybody any thoughts on how to construct such a base, without major carpentry, or weight problems?
I've had several ideas, but none seen particularly feasible! This is quite the largest single vehicle base I've ever considered, definitely outside my comfort zone!!
Dave

[Jim R]

Hi Dave
Now that is something I would enjoy watching you build. Looks great. I think I would make the base required from polystyrene blocks covered in that paper mache stuff - Sculptmold I think it's called. That would keep the weight down.
Jim

[Tim Marlow]

Only thing I can think of is to use plywood or foam board to keep the weight down. Decent sides and cross bracing should keep it rigid. Probably one for the John and Ron show though.

[minitnkr]

I can attest to the rigidity of polystyrene foam blocks/sheets as almost all of the scenery on the 'Tiger Recovery in the Tyrol' & '.....layout resurrection' is constructed of same. Glued together with PVA (Elmers). Easy to acquire, carve, & paint. Very light in weight.

[spanner570]

Yep, polystyrene blocks. I use the packings from washing machines and the like. Simply stack them up until you have your required depth.
Glued, as Paul writes, using PVA or similar.
If you are worried about the diorama flexing, start by sticking the bottom layer of blocks on a single piece of 4mm plywood. Then set to carving your trench.

Ron

[outrunner]

I can not help with diorama ideas Dave, but I will be keenly watching this build as that is just the type of odd vehicle that I like.


Andy.

[adt70hk]

The squirty expanding insulation foam might be a solution. Very easy to cut into any shape with a simple serated kitchen knife... And couldn't virtually no dust...... Sanding though is another matter.....

Have a look here....https://www.scale-models.co.uk/threa...03/post-458006.

Hope you work it out Dave.

ATB.

Andrew

[JR]

Agree with Ron, you need the lightness of the foam coupled with the ridged ply for the base .
Sculptmold as Jim says is very light and can be built up on itself to give the hight for the soil .
Just seen Andrew suggestion as well , that's worth checking out .
Will make a great Dio .

[Gern]

Yeah. I'd go with three layers of 20mm blue insulation board. One covering the whole base, and two pieces either side with a 50mm gap between them glued to a 6mm MDF base. Some bashing around with something sharp at the base and sides of the trench (I'd do that before fitting the foam to the base as access will be much easier) will give you a nice rough surface. A thin layer of filler or fine sand fixed with PVA will give you a nice hard surface without ading too much weight.

When you going for this? I bought one in the same sale and I'd be watching like a hawk!

[rtfoe]

Every suggestion mention above is doable Dave and very helpful. To roughen and texture the foam and keep it light is to add tissue to your polyfilla mix, use a stuff brush and stipple the surface.
If you find carving an obstacle you could melt and shape the foam with a soldering iron tool. Mind you it gives off fumes.

Cheers,
Richard

[Dave Ward]

WELL,
thanks for all the suggestions and tips, there's certainly a lot of ideas there for me to mull over. I think this will be a long project, as I reckon the base will take a fair amount of time & the BTM-3 itself looks a pretty complex build. Integrating them into a diorama will be 'interesting', as it isn't a matter of a vehicle on a surface, but a vehicle digging into a surface!
This will be a project for later in the year, I might experiment with the foams on a simple diorama before attempting this - I've never used the foam before!
Cheers
Dave
Ps - I've just looked at the box - it says 'Total Plastic Parts 770+' and there's a PE fret. That's the largest number of parts of all the models in my stash........................

[adt70hk]

WELL,
thanks for all the suggestions and tips, there's certainly a lot of ideas there for me to mull over. I think this will be a long project, as I reckon the base will take a fair amount of time & the BTM-3 itself looks a pretty complex build. Integrating them into a diorama will be 'interesting', as it isn't a matter of a vehicle on a surface, but a vehicle digging into a surface!
This will be a project for later in the year, I might experiment with the foams on a simple diorama before attempting this - I've never used the foam before!
Cheers
Dave
Ps - I've just looked at the box - it says 'Total Plastic Parts 770+' and there's a PE fret. That's the largest number of parts of all the models in my stash........................

770 parts.... That's mental....That equates to about 40 of the quick-build kits Junior and I do....

[Dave Ward]

It's probably the most expensive model in my stash, as well! I think I paid around £50 for it, in one of John's special sales.................... ( vast majority are <£15 )
Dave

[adt70hk]

It does look very intriguing Dave and I'm surprised is not more.

Will be interested to see how this goes together...... Just need to watch the video.

ATB.

Andrew

[outrunner]

Following on from Dave's post I felt that I really must have one of these vehicles as trucks, tractors and machinery is my thing. Looking around the few that were in the UK all looked a bit pricey until I came across one in a local modelshop about 50 miles away, up here that counts as local! I managed to get it for £45.99 delivered so there may be 2 of them on the forum sometime this year, I blame Dave for unearthing this must have model.

Andy.