Su101 and added Su102 goodness. Third Time Lucky?

[SleeperService]

Way, Way back in the mists of time I foolishly started a couple of scratch-builds HERE which TBH was a bit much for my state of mind at the time so like nearly everything else I've started it joined the Boxes of Doom. Part of the problem was using the drawings in this:

  

Not a smart idea as it turned out as the drawings weren't too good and I couldn't get the rear end looking right so just walked away from them.

Earlier this year I found this :

and on page 38 my turmoil and distress came to an end. So I started again

 

However showing foolishness has no limits at SleeperCentral I rapidly got myself in trouble at the rear end again. So I decided to study the photos of the Kubinka survivor with the drawings and make notes using my favourite red pen. 

As my sleep pattern is a little erratic I made a start at about 3am and have got this far with the third, and had better be the final, attempt.

 

 

Ignore the curved sides they are slightly but most is macro setting artistry. There were several things not too good about these one being the driving compartment quickly reaching 50deg C in spring EEK! I'll try and show Comrade Driver Andrei being extracted by a couple of concerned Comrades so I'll make a token effort at the driving compartment. The upper hull shows what the suspension mounts must have looked like. Note my use of off-cuts of card glued together to save money and the environment The front plate will brace the sides nicely but I may put a stiffener along the RHS inner to make doubly sure.

 

 

Here is the side showing the mounts again, my appalling joinery skills too. Well not actually, these were built from flat plates welded together so the gaps are deliberate to break up the weld effect. In places they were quite rough. I'm sure they'll come out OK in the end..... 

[SleeperService]

This is a week's progress!

 

 

Rear idler mounts finally fit where they should, the rear plate does the same and the front plate matches the rear. Considering the multiple angles I've had to consider I'm actually quite happy with this. Most of the remaining components can be directly measured from what's built.

 

I have been trying to work out the progress of these designs and had got partway when I found these sites HERE and HERE TOO which confirmed some of my thoughts and added more.

 

Basically Uralmash 1 became Su-101 when Su-102 was built. When that died during the trials it reverted back to Uralmash 1. Uralmash 1 was built and tested revealing several 'issues' not least the driving compartment overheating. It had a direct vision port in the front plate with a periscope in the hull roof for the driver. Many of the controls were mounted on the front plate rather than the floor. There was some protection from the engine but the final drive was in the same space as the driver, the driver also benefited from the exhaust fumes that were drawn in to his area. Little wonder that 7-10Km was about as far as he could go when buttoned up.

At the same time there was a second hull built for firing trials. These went very well and positive comments were made about the rear access door among other things.

 

The Su-102 was meant to be a 122mm gun version but incorporated many improvements from the trials already run. The driving compartment was isolated from all drive components, controls were moved to the floor, attempts to make a tunnel to the rear compartment were incorporated, an exhaust shroud was introduced, the drivers position was moved back 250mm, the vision port deleted,and other details attended too. With the design starting to show potential both vehicles were soon returned to the plant for a rebuild. The tunnel was sorted, the drivers position was moved back and the partitions received insulation, the exhaust shroud was lengthened, the vision port aperture welded up, cooling improved including the two vents ahead of the drivers hatch which, in turn, was modified with different vision arrangements. Finally torsion bar hinges were fitted to the RHS of the engine plates for areas that could be opened without having to remove the hull roof plate, in turn that needed the gun to be removed. The preserved vehicle reflects the final build standard, Su-102 suffered cracking of the gun mount and was scrapped.

So I'll be doing Uralmash 1 as first built and the Su-102 to the final standard.

 

Now a question. I had intended to use resin roadwheels and track on these leaving just the drive and idler as injection items. From correspondence with the manufacturer it now appears that the wheels will not be re-run so I'll be looking at kit wheels too. Would this be OK @Mjwomack Oh Beloved Leader?   

[Mjwomack]

I crafted the rules for this GB with an allowance of 25% IM parts to allow for raiding of the spares box *for those hard/ impossible to source parts. So, absolutely no problem here- nice to know that I crafted something properly for once😜

I remember the prototypes GB, it ended badly for me as well- Trevithick's pioneering locomotive was coming along perfectly fine and then I had a moment and put my fist through it repeatedly. note to self, Airfix plastic is surprisingly painful when you punch it. So, as a personal level I'm very pleased to see that this didn't suffer the same fate and gland your back in the ring with it.

We're all rooting for you

Michael

 

* or maybe in this case, going out and buying a kit just for the wheels- support the local economy😽

[JeroenS]

Some very nice scratchbuilding here, a good thing you put it back on the bench. Good background story too!

[trickyrich]

it's really nice to see proper scratchbuilding at work, you're doing a great job from the looks of those pictures.

 

Unless you really want to punish yourself and scratch build and case some wheels then I think plastic wheels from a kit would be fine. Those if you'r up for casting (it's actually quite easy) you could use a plastic wheel to make a mould?

[SleeperService]

On 3/26/2021 at 2:48 PM, Mjwomack said:

I crafted the rules for this GB with an allowance of 25% IM parts to allow for raiding of the spares box *for those hard/ impossible to source parts. So, absolutely no problem here- nice to know that I crafted something properly for once😜

I remember the prototypes GB, it ended badly for me as well- Trevithick's pioneering locomotive was coming along perfectly fine and then I had a moment and put my fist through it repeatedly. note to self, Airfix plastic is surprisingly painful when you punch it. So, as a personal level I'm very pleased to see that this didn't suffer the same fate and gland your back in the ring with it.

We're all rooting for you

Michael

 

* or maybe in this case, going out and buying a kit just for the wheels- support the local economy😽

 

Thank you Michael, after putting my planned 3D Printed project on the back burner in a moment of sanity I didn't really want to change again. The Prototypes GB was fun but several also fell so we are in good company :D I have brought a small hammer after reading your cautionary tale. 

19 hours ago, JeroenS said:

Some very nice scratchbuilding here, a good thing you put it back on the bench. Good background story too!

 

Thank you Jeroen. the original hulls are now reduced to produce and the plastic will be making a reappearance. As with a lot of these projects the stuff you find while researching is often fascinating. Trouble is I now know about the Su-122-54  

17 hours ago, trickyrich said:

it's really nice to see proper scratchbuilding at work, you're doing a great job from the looks of those pictures.

 

Unless you really want to punish yourself and scratch build and case some wheels then I think plastic wheels from a kit would be fine. Those if you'r up for casting (it's actually quite easy) you could use a plastic wheel to make a mould?

You Sir have a lot to answer for. Seeing your skill and insanity genius at work made me believe I could do similar. At least now I'm not so far behind ;) Your appreciation is all the more valued and I hope to maintain standards if not improve. As for the road wheels a trip into the stash seems rather better to me than learning resin. Maybe later. 😜