Skylab, 1/100, Scratchbuild

[Bandsaw Steve]

2 hours ago, bianfuxia said:

Awesome work. And as a fellow Dad, there's nothing better than hearing kiddo say "your model looks cool Dad". 

True, but I also kind of enjoy all of the rolling of eyes and shaking of heads. Best of all is keeping up with all the latest words for ‘nerd’ and ‘dork’ 🤣

[Bandsaw Steve]

3 minutes ago, 81-er said:

I know it's not that, but my first thought on reading that was "do they need cash in space?" 

 

The stand is really good, Steve, nicely done there. Is the Mirage made from metal, or just foiled?

 

James

Yeah I knew the ATM acronym would attract some flak sooner or later. In this case it stands for ‘Apollo Telescope Mount’.

 

The Mirage is scratchbuilt from wood and skinned with printer’s aluminium lithoplate. The project has been dormant for a while but does have its own WIP here on BM. I’m hoping to get back to it in a few months. 

[81-er]

I'll have to hunt that one out then, Steve, it looks superb in that photo

 

James

[Bandsaw Steve]

20 minutes ago, 81-er said:

I'll have to hunt that one out then, Steve, it looks superb in that photo

 

James

Thanks mate. It’s fairly well buried at the moment but if you use the BM search tool and search for ‘Wigram’ it’ll be fairly near the top of the stack because one of the early posts talks about a Mirage display at RNZAF Wigram.

 

Do be warned though, there’s a fair bit of silly stuff in there, at least up until @general melchett comes along and establishes some much needed order and discipline.

[Bobby No Mac]

Just been catching up with this masterclass in carpentry, metalwork and vac-forming. Top work Steve, very inspiring and informative 

[Bandsaw Steve]

Mistakes of Omission

 

So far this project has gone remarkably smoothly and has benefitted from some notable good luck with respect to finding various things of exactly the right size and shape.

Inevitably something was going to go wrong. In this post, I am happy to say, I have had a couple of mistakes and 'issues' to address, all of which are completely of my own making.  It was about time really, If I ever get smooth sailing all the way to the end of a project then I'm probably not testing myself adequately.

The first issue is my failure to adequately research the detailed shape of the area around the EVA access hatch. The geometry in this area is much more complex than I realized.

 

Here is a view of the relevant section of NASA’s model in the Esperance community museum.

 

The photo below is annotated to make the issue clearer.

The orange rectangle marks the EVA hatch.  The red lines mark out a projection of the edge of the orbital workshop assembly cut at 90 degrees to the long axis of the ship.

Note that the EVA hatch sits below that 90 degree projection of the edge of the workshop.  In other words, it’s set within a sort of recessed ‘portico’ within the limits of the workshop module.  

 

Since this whole area is recessed, none of it can be seen in any purely orthogonal set of drawings.

 

 

With these facts in mind I now realize that when I made the front workshop bulkhead (see photo below) instead of modelling it as a single flat circular panel,  I should have cut the MDF into a three-quarters of a circle segment and recessed the final quarter into the workshop to a depth of about 2 cm. That would have formed a nice ‘portico’.

That would have been easy to do at the time, but to correct this now would be a nightmare. So now my cunning plan is to ignore the whole issue and continue as if blissfully ignorant. I’m hoping you will approve of this slap-dash approach and not notify the authorities. 🤫

 

Instead of fixing the ‘EVA door is supposed to be in a porch’ problem I just pressed on and sectioned off a quarter of the front of the bulkhead with a couple of plastic triangles as below.

 

I then added the EVA door into a highly inaccurate but ‘as close to accurate as possible’ position and added some arbitrary surface ‘greeblies’ (shown below). Later on I found some reasonable photos of the real thing and replaced these 'greeblies' with some simple but much more accurate details.

 

As part of – yet another – mistake of omission I had not really thought very much about how to make the conical shroud that covers the front of the workshop (where the MDF is currently exposed).  In some photos this appears to be formed from a thin, rough, wrinkly metallic foil and in others it almost has a sort fabric look about it. Although I had not really planned this out I think I came up with a simple and reasonably effective solution. I cut off a 3mm length of PVC piping and went to my local hobby shop and bought some Milliput.  I’ve used Milliput in the past before and it’s brilliant stuff but I’ve never used it for something quite as large as this.

 

@mollythedog is a master user of Milliput. He builds entire ship models -albeit very small ones - out of this stuff.  So, when he recommended mixing the epoxy-putty (in this case black) with the hardening agent on a roughly 60 / 40 basis rather the 50 / 50 split in the official instructions, I took note.  Molly maintains that putting less hardening agent in the mix keeps the putty softer and ‘open’ for work longer but has no detrimental effect on the final strength.

Here’s the mix that I used. As per Molly’s recommendation it’s about a 60 / 40 split and this worked nicely for me.

 

As I’m sure you all know the two sausages must be thoroughly ‘worked’ together and blended to a completely uniform shade before you can do anything with them. Here’s the start of the process. It looks like… Ummm…

 

Anyway, after a fair bit of mixing and sculpting I had formed the basic conical structure. Note how the PVC circle has formed a sort of ‘dam’ against which I have pushed up the Milliput.

 

By using the face of a fine curved file I was able to impart a nice texture and  series of wrinkles into the ‘fabric’  I’m not sure that this is completely accurate but it’s not bad.  (Note how in the photo below the greeblies have been updated and improved).

 

There is a similar, but much flatter, profile cone at the rear of the workshop. This too was something that I had no real plan on how to deal with so just waded in and tried making it with Milliput. By the end of it I was starting to wonder if I’d taken up pottery for a hobby.

(Sorry about the blurry photo and the creepy-looking dude staring out of the google-home screen. I have no idea what that was about but it all looks down-right Orwellian here!)

 

 

This is a better view and it shows the final product. Despite all of the black mess smeared all over the place - which BTW is very easily dealt with - I was quite pleased with this. Full marks to Milliput! 

 

By the end of all this malarky I had this...

 

and this.  Not perfect but it could be worse.👍

 

Note that the solar sail is temporarily affixed but even after just a few minutes is sagging dreadfully. How to fix that will be in the next update. That’s when you will see what ‘failure to plan’ really is all about. 😱

 

Best Regards,

Bandsaw Steve.

[ArnoldAmbrose]

Gidday Steve, you come up with some interesting build methods, and obviously you're not afraid to try new ideas. That Milliput seems to have worked well. If you ever decide to do a WW2 German tank I think you've got the Zimmerit mastered.

Regards, Jeff.

[Bandsaw Steve]

11 minutes ago, ArnoldAmbrose said:

That Milliput seems to have worked well. If you ever decide to do a WW2 German tank I think you've got the Zimmerit mastered.

Regards, Jeff.

Yes, it would be ideal for that. You might remember I used it for the blast-bag on the PZH-2000.

[dnl42]

This looks quite excellent.

 

On 11/25/2023 at 5:27 AM, Bandsaw Steve said:

smooth sailing all the way to the end of a project then I'm probably not testing myself adequately

That sir, is a sound observation of so many endeavors...

[Bandsaw Steve]

Significant Rework

 

One of the recurring themes in my Britmodeller ramblings is that scratchbuilders must not only consider a model’s accuracy but also its strength. When building a kit, generally speaking, the parts will interlock in such a way that the whole structure will be coherent and stable.   This is because it is generally designed by a competent engineer. With scratchbuilding however, it’s up to the builder to consider this for himself / herself and, as I’m about to demonstrate, if you don’t you can end up creating significant complications.

 

Back at the start of this group-build one of the first jobs I tackled was making the solar-sail.  Foolishly, in my rush to advance the project, I gave little thought as to how I would attach this large flapping sail of wood, plastic, and aluminum onto the side of the workshop. I did plan ahead enough to ensure that there was a thick disc of MDF in the critical location onto which I could later anchor the sail's arm (see below) but beyond that my plan was, 'it’ll be all right, I’ll work something out’.  I was wrong on both counts.

 

 

in the photo below it all looks OK, but the sail is currently just resting on the workbench, it's not attached in any way to the rest of the model and I've got no real plan as how to achieve this.

 

The problem was that with no more than an awkwardly angled butt-joint I had to somehow hold this whole big sticking-out thing in place with no external supports. What made it worse is that with all of the  weight of the sails behind the support arm there was a significant twisting moment that I had no way to counter. So, even when I finally came up with the ‘brilliant’ plan of supporting the arm with a length of carbon-fibre stuck into the side of the workshop…

 

I was still, inevitably, left with a sail that was prone to droop and look very silly.

 

It was definitely time for some significant re-work.

The first job was to cut a slot, exactly the same width as the piece of plywood that I planned to use for the sail’s arm across the whole of the workshop.

 

And then, make a new arm with a significant root that would fit into the slot.  Note that the weird 'half-crescent' shape' is because the central core of the workshop is made from PVC piping and it proved a bit more difficult to carve out than did the MDF. Ultimately there was no real point in removing the PVC so I just worked around it by cutting out a rough rebate in the arm's root structure.

 

Now the arm fitted into the slot nice and tightly and even without glue was firmly affixed and could not twist. Achieving a friction fit like this is a good sign that things are going to work out from a structural point of view.

 

Of course now I had to re-build the sails themselves because the old ones were firmly attached to the original arm. The method used is very similar to that which I used to build the last set but this time I put two carbon-fibre rods in each sail rather than one because, once again, I was thinking more about strength.

 

The result is much more satisfactory with sails that look almost identical to the last set but are much more firmly attached and have no chance of sagging.

 

With only two days remaining on this group build I'm hoping that there's still one more update left to go. I'm planning on spending a fair bit of time on this project tomorrow and hope to have one last update to post tomorrow night.

 

Till then, stay safe.

Bandsaw Steve 

 

 

 

[hendie]

Courageous man, Steve.  I always find it nerve wracking to hack into already completed scratchings... I'm always convinced I'll just make the darned thing worse.

Nice recovery though.

 

 

[ArnoldAmbrose]

1 hour ago, Bandsaw Steve said:

but this time I put two carbon-fibre rods in each sail rather than one because, once again, I was thinking more about strength.

Gidday Steve, my philosophy is "why have one when you can have half a dozen". I have a highly developed sense of overkill. It was courageous hacking into the model like that but it seems that you've solved the problem of the droop. 😁 Well done.

 

1 hour ago, Bandsaw Steve said:

With only two days remaining on this group build

I thought Enzo the Generous granted another two weeks extension on November 25th. Good luck tomorrow. Regards, Jeff.

[Bandsaw Steve]

10 minutes ago, ArnoldAmbrose said:

of . 😁

 

I thought Enzo the Generous granted another two weeks extension on November 25th. Good luck tomorrow. Regards, Jeff.

Oh dear. I was unaware of that. 
 

there might need to be some work on that horrible gantry arrangement yet! 😱

[bianfuxia]

This is amazing work! I am learning so much from this - not only about construction techniques but also about Skylab. I had no idea it had literally a little front balcony!

[Bandsaw Steve]

1 hour ago, bianfuxia said:

This is amazing work! I am learning so much from this - not only about construction techniques but also about Skylab. I had no idea it had literally a little front balcony!

yeah - neither did I unfortunately! 😬

[Bandsaw Steve]

The Front Rear End

 

In the case of spaceships ‘up and down’ and ‘front and back’ can be highly ambiguous terms.   I’ve already made the rocket nozzle / bell, but now I’ve got to make the odd-shaped ‘square blob with rounded off corners’ that sits at the rear end of the CSM but the front end of Skylab.

 

 

Presumably this is some sort of covering for the wiring and piping for the engine. Let’s call it the ‘protective cover’ for want of a better name.  Photos of this area are surprisingly rare. Almost all photos of the CSM (both during the Apollo and Skylab phases) taken from the 'front' showing off the streamlined pointy end and not the 'rear' (which in this context is the 'front') showing off the engine details.

The first job is to fill the large void that I left when I converted a reticulation sprinkler outlet to the CSM fuselage. To do this I’m using a piece of HIPS plastic cut to an appropriate circular profile and wedged / glued into the void.

 

 

You might also note that I've added a piece of aluminum tube to the central knitting needle to provide a solid attachment point for the nozzle.

I then cut a circular piece of aluminum lithoplate to form the basis of a disk sitting behind the ‘protective cover’. I love aluminum lithoplate, this stuff is so cheap, so easy to work with and gives such a good finish that I’m amazed more modelers don’t use it.

 

Now cut out a square piece of 3mm MDF, round off the corners and drill a hole through the center.

 

Then dress the whole thing up with a couple of appropriate looking tubes and a circular base and some etched structural ribs until you have something that looks like this. Subsequently, a little bit more detailing went onto this part; but you get the idea.

😱

 

Add a thin band to the exterior of the rocket nozzle...

 

and dry-fit the whole assembly to check that it all goes together OK – which it does.

 

That’s really the last major external component to be built except for the whole ‘gantry’ ‘scaffold’ thing that is holding the ATM in position. I can’t put that job off any longer. I’ve had a long time to think about this daunting job and have cobbled together a provisional plan of attack. I’m thinking it’s going to be a very tricky piece of work so stay tuned because it might just be a train crash, and everyone loves a train crash! ❤️

 

Best Regards,

Bandsaw Steve

[KevinK]

24 minutes ago, Bandsaw Steve said:

Presumably this is some sort of covering for the wiring and piping for the engine. Let’s call it the ‘protective cover’ for want of a better name.

 

That's exactly what it is, Steve.

 

The black circle visible in the red panel at the corner of the cover, visible in the photo, is the housing for the fill/drain/vent valves for the SM systems. There are two of the fill/drain/vent complexes, one on each side of the 'protective cover', one for fuels and one for oxidizers - safety. The SM was filled with propellants and other gases/liquids (oxygen, hydrogen, helium, nitrogen) when in the vertical nose-up position, so 'low point' access was at the skirt.

 

The cover is there not just to protect the plumbing from the radiant heat from the SPS engine but also the long-term solar heating.

 

...and, by the way, your work is some of the best scratchbuilding I have seen!

[Bandsaw Steve]

Wow! That’s all very interesting. Thanks for the info and the encouragement. 👍

 

 

[KevinK]

It may be a bit late now but there are good walk-around photos of the backup Skylab CSM-119 at:

 

http://heroicrelics.org/ksc/apollo-csm-119/dsc05850.jpg.html

 

and another CSM (105) displayed as the Apollo-Soyuz exhibit at the NASM:

 

http://heroicrelics.org/ksc/apollo-csm-119/dsc05850.jpg.html

[Bandsaw Steve]

Ah! Fantastic. A shame I have not seen those before. Having seen these now I think I might have another crack at that protective cover, with a bit less guesswork next time. 👍

[bianfuxia]

On 12/9/2023 at 8:58 PM, Bandsaw Steve said:

Ah! Fantastic. A shame I have not seen those before. Having seen these now I think I might have another crack at that protective cover, with a bit less guesswork next time. 👍

Awesome work yet again. 

I think the pics I linked for you a while back had a good close up of that end of the CSM at the Air & Space 

[Bandsaw Steve]

When I started on this bit I knew that I had seen some good photos of this before but I was damned if I could find them. 
 

I’ve got them now! 👍

[ArnoldAmbrose]

Gidday Steve, it's very clever (brilliant in fact) of you how you use mundane items to make parts for your models. I've probably said this or similar earlier. Your models turn out terrific. Regards, Jeff.

[IPMS19]

- -HI Richie, there you are hidden, the subject by itself is not in the center of my interest even if i'm an inconditionnal of Startrek and Stargate SG1, But the work  you are accomplishing  is tremendous, hat off Sir

[Bandsaw Steve]

Thanks very much @IPMS19. Not sure where you got the 'Richie' from - but never mind. Pleased you are enjoying the thread.

Steve