Blaster EE-3 Breech Greeblie


Active Hunter
Im actually really liking the look of that piece Alan. You might be onto something
I can give the diameter for what I calculated the disc at for mine when I get home later tonight


Well-Known Hunter
These are just the Futaba control wheels, the other RC manufacturers had there own versions. These wheels are something that would have been easy to come by in a SPFX house, every servo came with a selection of control horns. Years ago I use to have a box of them. Just a thought.


I thought these were interesting finds:




Outer side of Art’s mock-up.

The inside is even more interesting, although I am sure the scale is way off:



I love that last photo, however it is way too wide. According to the site, the diameter of the center hole is 6mm. 1.5 inches puts the total estimated diameter of the breech disc at about 38mm based on Art’s estimated breech disc diameter. That would make the breech disc have a diameter about as wide as the inner lowered section with the three holes in it, thus this disc is very very large.

Obviously those upper photos show the real world disc being too thick. Perhaps they would have turned it down?


From scrutinizing those two screen grabs you posted up there Art Andrews I surmise that the circular breech greeblies are not just discs, but are pulley wheels.



This would be an unnatural phenomenon based on the curvature of the breech at that very location.
Also, the top most dark area looks dark enough to be a cutout for securing a line, as one would find on many pulley wheels like this one taken from a WWII RAF fighter plane:


I realize with my red lines in the picture, covering up the two edge lines, they can’t really be viewed, so you will need to enlarge the top photo and look there.


Active Hunter
Yeah, one of my designs was as a pulley as well. Its so hard to tell whats going on in that photo. I printed both, but ended up using the version with only the raised rim for now until something better comes along


Active Hunter
Idea...if a pulley wheel was used, they probably removed the connecting hardware and separated the two halves... One for each side?


Well-Known Hunter
Did a search for Meccano pulley there looks like there are number of possibilities.

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Exactly, I had stacks of this stuff when I was a kid and it was widely available in the UK at the time of filming. which was why it sprang to mind but I didn't find anything that really took my fancy although there were some interesting pieces. I had a look through what I still had in the loft and if I recall correctly I had pretty much everything you have pictured there. I also considered plumbing type flanges knowing that plumbing parts were clearly in use on other props.


Active Hunter
Ok so I've started looking at this again. May I ask how you guys are getting 38mm for the total diameter of the breech disk? I drew up everything using a couple of different views and I keep getting closer to 42.5mm, which is actually what my old design from before came out to as well haha. From the shot in the executor bridge with Gary Kurtz I see what I take to be a rim, somewhat like on a coin or some of the pulleys listed earlier, that is either raised or recessed and the inner diameter on that I'm getting closer to 38mm, but the main diameter I still get about 42.5mm.
Here's a couple photos of estimates along side a comparison of my current design for the disc
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Active Hunter
So I've played around with this some more and may have kinda gone a little hog-wild on the redesign here, hahaha, but bare with me. So at first I simply did a slight redesign to my old model with the incorporated pulley features and reduced the outer diameter back to 42mm, and this is what I came up with for that.
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But I still wasn't entirely happy with that, so I decided take another look at what few photos of the Disk/Pulley we have and start again from scratch.. The more I look at these photos the more I cant help but lean towards the large hole we see as actually being a slot instead... There are just some funky shots like those from on the executor bridge where it almost looks like it has an elongated shape to it that it shouldn't have if it was just a simple hole. I also played around with the actual pulley part for a while and I ultimately decided to make it more of a simple groove as to me it just looks a little too shallow to be that of an actual pulley from one of the hallway photos showing the other side of the blaster. Not claiming any accuracy here as this is really a very large shot in the dark, but this is what I now think I am seeing. It also looks as though the Disk fell off at some point much like many of the other greebles and was re-glued back on in a slightly different positions throughout filming. But yeah, curious what you guys think about this

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I haven't looked at the holes yet but I do completely agree that it is a full pulley and not a split one.


Active Hunter
If this breech greeblie was in fact a pulley, I believe it was one without any holes originally that they modified for whatever reason and added the holes to it. Mainly because of balance. It makes no sense that a manufacturer would make a pulley wheel like this with an unbalanced set of holes and so far I personally have not seen one yet.


KenChan Wow! That is fantastic work! I am leaning toward your assertion that perhaps these are not perfect circles but abnormal holes. The larger photos are very helpful along with your detailed renders of your designed disc.

Possible side observation:
In some of those photos, the V8 Rod is missing, having been knocked off. Is it just me or does it appear that, based on the location of the larger hole on the disc, in relation to other features of the Webley, the disc itself is moving/rotating slightly? Perhaps that might be telling somewhat as to how the builders attached these discs?

If this breech greeblie was in fact a pulley, I believe it was one without any holes originally that they modified for whatever reason and added the holes to it. Mainly because of balance. It makes no sense that a manufacturer would make a pulley wheel like this with an unbalanced set of holes and so far I personally have not seen one yet.
I think there is some logic to your line of reasoning, however, the deeper I have dived into vintage high speed audio equipment that utilize pulleys (from the era that these discs/pulleys would likely have come from), I am regularly surprised by what would appear to be randomly positioned holes on pulleys (I am sure the reality is they are not randomly placed) for what I have to believe are reasons of balancing these pulley wheels at high rotational speeds. Even more strange is the varying quantity of holes per pulley, as well as their differences in hole size and in the arrangement of each hole to one another which typically, to the naked eye, is not what one would consider symmetrical (which one would assume to be necessary for balance).

I don’t want to infer every one of those pulley wheels was custom balanced, nor do I want to make it seen that most or even half of them are this way (the vast majority are not like this), but a surprising number of them are very irregular.

Of course now that I’ve said this I can’t seem to find any good reference pics.


Active Hunter
You wanna laugh, that's exactly where my mind went when redesigning it! Some sort of somewhat slow moving wheel/pulley commonly seen in audio equipment, Hahaha! A small pulley really only needs to be balanced if its going to be moving at a somewhat high RPM, and it can basically look however it wants if its moving at a low RPM where balance becomes a non-issue. The only thing about the pulley aspect I somewhat dislike is that the entire disk base itself looks to only be somewhere in the 3-4mm in height range, which doesn't really leave a whole lot of room for conventional pulley to function and it’d have to be using a very small rubber belt of some kind (which again you can often find in vintage cassette players and what not).

Yeah I definitely agree that the disk is changes orientation throughout the film, much like the Unimax switch did they probably fell off and were glued back on. I suspect that they just used CA+ glue/superglue or maybe even hot glue when putting them on originally. I used to use hot glue on mine and they would fall off quite easily over time before I started using rare-earth magnets so as not to damage the Webley. It actually appears to be in that 2nd orientation where the large slot is pointing down towards the lower right for a good majority of the film. Here's a comparison to show what I mean incorporating Raf's info from his ESB Chronology thread (NOTE** I have readded in the pulley rim to my model since the last photos)
The Empire Strikes Back - Boba Fett's on stage chronology.
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Another thing that's weird though is I almost think I can actually see a 2nd smaller hole half way between the already known small hole and the larger hole/slot on top in a couple of the photos where the v8 arm is missing, but I cant see any part of it in the Cloud City Hallway close-up photos unless its somehow perfectly hidden under the top right corner of the v8 arm. I didn't add it to my model yet because of this
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