25 May 2023

Old Elementary: 6931 FX Star Patroller set review and MOCs

Posted by Kev Levell

As time progresses, it feels as if the prices of LEGO® Classic Space sets are flying out of my reach; certainly the boxed examples in good condition. I know some of the gaps in my collection may now never be filled (and that’s fine, because being completist is a fool’s errand), however there’s always the odd occasion when the Classic Space Moon aligns with a healthier bank balance and I do manage to acquire a long hankered-after gem.

Join me today for a nostalgic flight back to 1985 with 6931 FX Star Patroller (aka Intergalactic Star Cruiser) as I look at its interesting elements, and create original MOCs using one of its most interesting: Tail 4 x 2 x 2 Aircraft Rocket Engine (Design ID 4746).

Fans of vintage LEGO face the perils of that awful auction place in order to feed our addiction (or, if you’re still in denial, “expand our collection”). The copy of set 6931 that I got lucky with had gone unsold at a succession of auction listings. I put in a ‘best offer’ of £55, and it was accepted! "Huzzah!" I shouted, and then the paranoid waiting began.
However, without a hitch, five days later, my 6931 arrived perfectly wrapped and seemingly in an unplayed-with condition; the bricks were pristine, museum quality!

The outer box does have a few weird holes, sticker damage and some ‘standard issue’ creases but the near-mint instructions and bricks lead me to believe this set was built just once and forgotten. Which of course is also a little melancholy, if you subscribe to the Toy Story mode of thinking, because here is a LEGO set that hasn’t been enjoyed. 

Until now.

It’s out of the ordinary for New Elementary to feature old sets like this, but Classic Space is still heavy in the zeitgeist, especially following the release of 10497 Galaxy Explorer and 40580 Blacktron Cruiser. I also suggested to our editor Tim that it might be nice to help promote his upcoming new book: LEGO Space 1978-1992! Furthermore, I thought there was an “Old Elementary” angle that we could cover; where we explore the geometry and possibilities of out-of-production elements.

The parts in 6931

6931 FX Star Patroller was released in 1985 and contains 218 parts, according to the front of the US box. Variations in approach to inventories means that 204 is the piece count on Bricklink, 227 on Rebrickable and 239 on Brickset. In any case, there's one astronaut minifigure and one brick-built robot. 

Printed parts

First, let’s take a peek at the printed parts, because to be honest, I’m struggling to think of another Classic Space set that rivals this for quantity: 22 in total, nearly 10% of the total parts in the set.

Especially notable is the hail of arrows!

Wedge Plate 8 x 8 with 4 x 4 Cutout (part 4475)

As for other parts, first is an element I’m very fond of: the not-quite-a-POOP wing wedge plate with cut-out.

Three are included in set 6931. It is very similar to part 6104 which features a smaller 3 x 4 cutout, and served as an updated verson from 1993 until 2005.

The ‘nose’ angle is the same as created by the standard space wings, parts 3933 & 3934. Part 4475 only ever appeared in Light Grey, in this and one other set from LEGOLAND Space: 6891 Gamma V Laser Craft. Three are provided in that set also.

Addendum: to clarify, 4475 has appeared in other colours, but in Light Grey it was only available in 6891 & 6931.

The wings create a 67°/23° diagonal across a 3x7 rectangle. Neither of the two nearest wing plates currently  available match this angle. 
I am sure it must be nostalgia on my part, but for some reason that old wing shape seems more elegant, pleasantly proportioned and more visually appealing (if you can forgive my hyperbole).

Tail 4 x 2 x 2 Aircraft Rocket Engine (part 4746)

Then there’s these jet engine bits - yeah, the one with a tail fin embedded in them. Two are included in Light Grey here, and there were three other colours - Black, Blue and White - across 28 sets (excluding the unreleased set 1526). However, Bricklink lists two other colours - Brown and Green, I assume these were ‘Q’ list parts (those made for exhibitions and LEGOLAND parks).

Honestly, this part is a real “what the heck!?”. The actual dimensions are closer to 5¼ x 2 x 2, but it is non-standard in its longest dimension (to measure) in either of the orientations it can be attached.

The rocket engine has many connection points:
  • axle connection from the rear
  • 2x2 anti-studs to the rear
  • stud with partially blocked bar hole at the tip
  • stud with bar holes that go all the way through from either side
  • teeth in-between studs of the foot 
  • 2x2 studs connection at the top

Minifig Neckwear Jet Pack with Front Stud (part 4736)

A fairly rare part in any of the four colours it comes in:
  • Blue - a single one is featured in set 6931 and one in 6952 Solar Power Transporter
  • Light Grey is also featured in two sets: 1558 and 6702
  • Yellow is only in 7324 City Advent Calendar from 2005
  • Black is the most common, but still only included in a total of 7 sets.

The jet pack was last seen in the LEGO Alien Conquest polybag 30141, in 2011. 

Part 4736 is thin in cross-section throughout its moulding, and is easily bent or deformed as a result. A few points of the design are particularly prone, and the part suffers bends from not much more than regular handling. 

Unsurprisingly there were many candidates for similar usage introduced during its production and since the part was retired. Below I have picked those that Bricklink lists as a ‘jet pack’ in the minifigure body wear category.

  • Minifig Neckwear Backpack First Order Trooper, pictured here in Red and also available in White (58017)
  • Minifig Neckwear Jet Pack with Nozzles, in Black and 5 (astoundingly highly priced) colours (64802)
  • Minifig Neckwear Jet Pack with 1 Stud and No Front, in Dark Bluish Grey and White (24217)
  • Minifig Neckwear Jet Pack with Twin Handles only available in White (6023)

There are of course many other minifigure body wear pieces that might be used to create jet packs, here are just four that I selected at random from my minifigure parts.

  • Minifig Neckwear Armour Breastplate with Shoulder Pads, 1 Front Stud and 2 Back Studs in four colours (11098)
  • Minifig Neckwear Bracket [One Stud] - there are two variants with subtly different geometry exist in a variety of colours (42446 or 28974)
  • Minifig Neckwear Front Harness with 4 Back Studs (41811) available in three colours
  • Minifig Neckwear Breastplate and Shoulder Pads [Hero Factory] 15339 available in four colours.

Panel 1 x 4 x 3 [Solid Studs] in Trans Dark Blue (part 4215a)

The inventory of parts in set 6931 does contain one other notable rare part: a now pretty expensive Trans Dark Blue 4 x 3 panel that came in this and 6959 Spyrius Lunar Launch Site. An update (4215b) with hollow studs came in three later sets, but still remains relatively rare in Trans Dark Blue.

Building LEGO set 6931

Old sets didn’t come in numbered bags and the instructions were, well, let’s call them concise. Consequently the process of building was just one linear endeavour, so I’ve chosen page ends or finished sub-assemblies as the stopping points for documenting each stage.

Cover & Pages 1, 2 & 3

Pages 4, 5 & 6

Pages 6, 7 & 8

Pages 9, 10 & Back Cover

I love the detachable and deployable sections so common in Classic Space ships. There’s a quirky elephant head I see in that back section too.

Although the build is not exactly difficult - in fact, everything is predictably straightforward - old instructions always need a slightly different 'spot the difference' approach to building that I find intoxicatingly nostalgic.
The rover fits neatly in the back and the finished ship is very, very swooshable. It really is a thing of joy.

6931 features an unusual colour combination: Trans Dark Blue canopies were more often combined with white as their main fuselage or wing colour.

Here's a simple swap-out to show what the 6931 FX Star Patroller looks like with a Trans-Yellow canopy. For a variety of reasons, I find myself preferring the Trans Blue original and I think for the purposes of identification, it's better to have the variety within the fleet. 
I like that the FX Patroller doesn't conform to a rigid formula that we might impose upon LEGO Classic Space sets. It frees things up and perhaps gives legitimacy to MOCs in the Neo-Classic mode that don't use the familiar light grey, blue and trans-yellow livery.

Would this old LEGO set be good value if it was released today?

It seems that back in 1985, 6931 FX Patroller was $19.99 in the US. My usual sources for locating UK prices bore no fruit, however, in a stroke of luck, I found another Evilbay listing that revealed the UK cost, in the form of a still-attached price sticker.

In the photo above by ebay member frco78 we can see clearly the price was once £13.99. (The completed auction listing is no longer available.)

£14 in 1985 would be around £40 in today’s money, although when this article was originally drafted in September 2022, that figure was nearer to £30. At that earlier price conversion, I think the set fares relatively well against similarly sized sets in the current LEGO line-up. Now, I'd say the set is probably on the slightly expensive side for what you get.
I paid £55, so allowing for inflation, rarity and other market influences, I still think I got a reasonable deal here. At time of release, my pocket money was about 25p a week, so this would have taken me what felt like an eternity to save for… and that's probably why I didn’t own it. I think I chose the slightly cheaper 6891 Gamma V Laser Craft (aka Intergalactic Freighter Dark Star) instead which was around £8 or £9 if I recall correctly.
I like the yellow astronauts but they were never my favourite, so if set 6931 were released today, perhaps I would find myself calling for another new colour to bring that value up a bit? Certainly there are plenty more colours that weren't available in 1985 - how about Lime, Dark Red, Tan, Teal or Dark Bluish Grey?


Nostalgia is always going to weigh heavily when reviewing sets I remember wanting from my childhood. Getting this set after more than thirty years delivered such thrills. In fact, I felt similar levels of excitement to when back in the early 2000s I acquired missing classics like sets 928, 6970 or 6980.
The less-common livery is what makes this set special in my eyes. Conceivably it could be considered to be just a slightly bigger version of 6891 Gamma V Laser Craft with a different colour scheme, however, the larger deployable cargo section that contains a rover gives the set an additional level of play value that I think justified the difference in price.
I feel lucky to have added this set to my collection, equally I would have done as an 11 or 12 year old. So, if you're in the market for some Classic Space and you can find it for anything like a similar price I'd very much recommend trying to add this to your collection too. I doubt you'll regret it.

MOCs using part 4746 Rocket Engine Tail

When I put a draft of this article in front of Tim, he said, “Great, fancy doing a MOC using the rocket bits?” 
I thought, "How am I gonna use the rocket bits?" but replied, "Sounds cool", bluffing Elon Musk levels of confidence. 
It took me quite a while and to be utterly honest, as much as I love how the rocket engine piece looks, the awkwardness of its dimensions and the ‘teeth between studs’ attachment at the foot make this a bit of a swine to use in less obvious, surprising and more interesting ways.

Fossil Fuelled

Initially, I tried using it in white as some kind of Pteranodon skeleton fossil, but felt it was never going to get there, and so it morphed into some kind of prehistoric shark skeleton fossil instead.

 It's a bit like a Stethacanthus or a Scapanorhynchus... maybe it could even be something from the second Avatar movie, or a relative of the bizarre-looking goblin shark. Either way, I don't think the jaw looks quite right and most sharks are made from gristly stuff (cartilage) so that might not produce this kind of fossil anyway.

If budgets were limitless, I would have loved to create a micro alpine scene using part 4746 in green as conifers. In the UK and Europe, availability of green was very limited (and borderline extortionate). In black however, the cost was a lot more justifiable and availability was plentiful!

Blacktron Trident

I managed to acquire a few more black rocket engines to add to my available parts, in an effort to explore further possibilities.

I had some of the maxironi (65473) sitting on my build table so I experimented with striped tentacles for a squid thing. Trying to deny what I knew was already in my heart... I had endeavoured to stay away from space, honestly I had. But that lovely 40580 Blacktron Cruiser was sitting on my shelf, taunting me!
A spaceship was very much dictated from this point onwards. You might also be onto something if you suggested it was a forgone conclusion from the outset!

Rocket Boot Robot

I felt that I still needed to explore the rocket engine's potential, and once again tried to attach a range of different elements to it.

I think it's fair to say that I wear my influences on my sleeve. I'd be surprised if anyone would fail to notice at least one of the sources my subconscious dragged inspiration for this robot from. 

He grew out of his rocket boots, but I feel that the robot owes less to the rocket engine parts than it does to our modern selection of parts.

On balance, I think the rocket engine piece does offer some interesting possibilities beyond the nifty greebling of its moulding. I don't think it is just a shortcut for some interesting sci-fi visual texture. And despite the challenges of its dimensions and awkward attachment points I'm actually a little sad this part is retired. I've no doubt that there are many ingenious uses that have still never been conceived of.

READ MORE: Kev creates more original models using old "Space Tools" elements

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  1. "4475 only ever appeared in Light Grey...." then you proceed to post a pic of it in blue just to taunt us! But then I went and looked it up, as well as 6104, and 3933/3934. Each of those is available in several different colors, so this section must be a typo and you were talking about some other part?

    1. Sorry, yes it does sound like that, now that I re-read it! I actually meant that although it has been available in other colours, in light gray it was only ever in those two sets. Apologies for the confusion!

  2. PS thanks for the review! The rocket part and tailfins that attach the same way are interesting in how they clutch inbetween studs. As a kid I recally that attachment feeling a bit flimsy, and it was weird to not have outer walls or tubes or any of the usual anti-stud type structures.

    I love the nostalgia and play value. But I think design-wise if this were released today we'd be a bit more harsh on it. It's completely studs-up construction. The rear cargo hold is a basic square box, and transitions awkwardly to the long column forward that connects to the cockpit section. There aren't any landing feet to speak of. And I know we used to complain about non-airtight cockpits.

    Compared with 60226 Mars Research Shuttle (273 pcs), or 60224 Satellite Service Mission (84 pcs), we can see where updated design and new parts have taken us. That said, the FX Star Patroller uses it's 204 parts to create something fairly large and with some good play, so I wouldn't be too harsh.

    I also love the box pics showing alternate builds!

    1. Thanks! Yes, it probably doesn't compare to modern sets or MOCs all that well. It's just got such charm that it reels you back in to thinking more favourably of it!

  3. Good review! This is one of those Classic Space sets that I've wanted for a long time but have never quite got up the nerve to buy. Here's my modernized MOC version;

    1. Nice work! Your version has really got it where it counts :-)

  4. I had this set! One of the few growing up since lego was so $$$. This set offered alot of imaginative play with all the multiple components (a ship, cargo hold, rover, a robot) where you could create any narrative and were not constricted by a fixed storyline. Would love to see a review of 6952: Solar Power Transporter. Great set & Great review!

    1. Hmmm, I have a reasonable boxed example of 6952... it's a great set too.

  5. For those who like those 3933 & 3934 wedge plates (which IMHO make more sense, as they're chainable), they're widely available in -modern- greys on Ali!

    1. The price of official ones in bley can be a bit steep. I couldn't have counterfeit stuff in my collection though.

    2. well, unless your collection consists of Kiddicraft parts..

    3. True if you only build with hollow 2x4 bricks.

  6. Seeing that lego space book end right before ice planet, spyrius and exploriens makes my inner 90s kid sad.

    1. There's enough LEGO Space material to fill another volume at least. Take us up to Alien Conquest and Galaxy Squad!

    2. So true 1992 is right where it starts to get good! 🙂

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  8. Neat review! Classic Space was before my time, but in hindsight I have quite a fondness for the theme's brick-built robots, which employed a lot of unusual and clever techniques to turn non-minifig parts into articulated, minifig-sized characters! Even in the present day I'm a big fan of articulated, brick-built characters, but these ones are extra impressive for being built from the relatively limited parts palette of their time. They also help quite a bit to diversify a cast of characters that was otherwise made up of nearly identical astronauts.

    Interestingly, German LEGO catalogs and print advertisements also gave most of these early LEGO Space robots unique names (and in many cases, even specializations)! The one in this set is Zip the Lab-Robot. Other Classic Space robots include Zilu the Mini-Robot, Zazza the Dish Robot, Zero the Communications Robot, Zyr the Vision-Robot, Zonu, and Zynar. Futuron subsequently introduced Zor the Sled-Robot and Zwil and Ling the Robot Pair (a pun on "Zwilling", the German word for "Twin").

    Since all these German robot names began with "Z", I can't help but wonder whether the names of Olivia's robots from LEGO Friends (Zobo, Zobita, and Zobito) were meant as a subtle LEGO Space reference!

    The rest of this set's design doesn't really stand out too much to me. While vehicles that split apart into modular segments are a timeless LEGO Space play feature, the rear section here doesn't seem to serve much purpose on its own besides as a stationary parking garage/refueling station for the planetary rover, and in that context it leaves me wishing that the wings could fold UP as well as down in order to conserve space at the landing site (though perhaps the designer intended for them to serve as outriggers and help stabilize the garage in a low-gravity environment).

    Also, while I don't mind unconventional color palettes, the Tr. Blue garage door contrasts poorly with the Bright Blue walls that surround it — this would bother me less if there were Grey parts separating the two, but as it is I'm not keen on the resulting appearance.

    1. As far as elements are concerned, the tail with jet engine is an odd one, and I feel its unconventional connection points often made it a little awkward to use outside its intended function (though I am impressed with your imaginative efforts to do so here).

      The length of the cone doesn't seem so odd to me when measured horizontally, since it's just 5 modules long plus the length of the front stud, but its vertical measurement when placed on its end is definitely quite awkward. I feel that the 2x2 octagonal cone and brick elements from the Aquazone theme had a lot more care put into keeping their proportions as SNOT-friendly as possible when building with them in either direction. And the cone itself is far steeper than any other cone, slope, OR wedge pieces that I can think of, so any attempts to extend the rocket cone will implicitly require a change in angle.

      While I grew up with old-school wedge plates like the ones in this set, I have little nostalgia for them. Both their 3/7 slope and their lack of stud notches along the leading edge often made them awkward to build with as a kid — and by the 90s, when I was growing up, there were more than enough 45-degree wedge plates with stud notches to make it clear that a better design COULD be possible.

      And while the single-stud rear cutout could open up interesting possibilities, I feel it was just as often an inconvenience that fans and set designers were forced to work around. I was very grateful in the late 90s when wedge plates with stud notches and more builder-friendly angles began showing up in Star Wars sets, and it doesn't surprise me that this trend has continued unabated in the years since.

      I suppose that to this set's credit, it's quite nice that it can still charm you just as sets like it did in your childhood. As a 90s kid, there are some sets from my childhood that I still have quite a bit of nostalgia for, but often it's hard to feel as fondly about a lot of them as I did back then due to their many apparent faults. Thanks so much for this retro review!

    2. Great insights Skye.

      I agree that the modern wedges are easier to use - and I'd definitely appreciate an update of this specific profile that was notched!

      I love that they had names for the robots!

  9. So parts 3933 & 3934 and part 4475 technically have a 22.5⁰ angle right? Because you can marry up eight of them and make a circle. That might be why it seems more pleasing than the others because it is geometrically half of one of the most common angles.

    1. Sadly, my measurement makes the angle 23°, so a full circle isn't possible.
      I did once lay them out to check that idea...

  10. I thought I was fairly well-versed in elements new and old, but DesignID 4746 was new to me, and I appreciate Kev and NewElementary for introducing me to it. Also, this set is a good reminder that the Classic Space livery was never quite as consistent as in our revisionist memories!

  11. Thanks :-)

    Yeah, we like to think the livery was pretty strict, but it was somewhat flexible!

    1. Arguably, there were three main color schemes; gray bottom/ blue top with trans yellow canopies, gray with trans-green canopies and occasional black highlights and white with trans-blue canopies and occasional blue highlights. The latter color scheme was streamlined and taken up into the Futuron, Exploriens and Space Police III themes.

    2. Ah, yes, but that's the thing, it IS arguable, but perhaps it's a futile argument because there's almost always an exception like 6931 here. Those categories ARE pretty loose too because there are sets that are mostly Light Grey from the early years with Trans-Yellow. Then there are mostly white sets in the 'white and blue' phase. It skips to a mostly blue livery too but there are white and blue smaller sets. We think of these things as having rules within the theme, but really they're little more than visual cues IMO.