Limited Run DaveP's Obi Static Parts Run 2022/23 (Sign-Up Closed)

DaveP

Master Member
RPF PREMIUM MEMBER
I'll keep watching this. Quite interested.
Thanks Markus. I've added you to the list. No obligation at this stage. Just so I can keep you updated with any announcements. (y)
Ok, put me down as interested if you're still compiling a list.
That's great. Thanks. List updated (y)
Forgive my ignorance here, but what will secure the balance pipe (emitter) onto the windvane? Does the threaded rod extend from the sink know/handwheel (pommel) all the way through the windvane and into the emitter? Is there a confirmed source for that threaded rod or does the community just come to that conclusion that it must have been used in order to hold it all together?

Finally, in regards to the windvane lettering and whether or not tape or paint or some other substance was covering the lettering: does anyone think that if there is indeed something covering the lettering, it could have specifically been added postproduction for those photos so that no discernible markings could be identified (by people like us)? I just find it highly suspect that they would bother to cover the markings for shooting when those markings would be impossible to see on camera.

Personally, I don't believe there is anything at all trying to cover any lettering, at least not during filming. I think the original stamping was either just super faint from when it was manufactured or time/wear and tear had worn down the brass to the point where you could barely make out any markings to begin with. From everything I see in photos, on film, etc. the color of the windvane is consistently the same weathered brass up and down.

There's no hard evidence for how the actual prop was held together. It would make sense to have a rod go the full length. The clamp goes some way to holding everything in place too.

Like I say though, no solid evidence for the exact type of fixing. For mine, I like the idea of a coach bolt, as used by others previously. the square head will sit nicely in the square hole of the metal part of the handwheel. Having had some difficulty finding a suitable candidate, I've opted to have mine made. It will be a coach bolt that runs the full length of the hilt.

1.jpg


There will be an emitter insert that threads on to the end of the bolt and will keep everything tightly sandwiched together.

In order to fix the actual emitter on to the insert, there is a set screw, which will be tightened from the inside. This avoids any fixing points being added to the emitter itself, and allows for the use of a vintage balance pipe, if you're lucky enough to have one. :)

The insert itself is based on the one seen in the Death Star death scene:

4K77_1_30_09.JPG


It is of course missing from other references, so perhaps another method was used elsewhere. Maybe this was added due to the nature of the shot, and because dropping the hilt on the floor over and over caused a previous attachment method to fail? Or perhaps it was subsequently painted black? All very difficult to say for certain, but either way, this is the reference that I've used as the basis for my design.

As for the tape on the wind vane... I'm leaving that open to interpretation. Personally, I'm in the tape camp based on what I see in this image:

WINDVANE_RING_COLOURISED.jpg


There is a light spot on the metal to the right, which can be seen literally disappearing up behind something that is covering it.

That's enough for me, but I'm happy for people to disagree and interpret it differently.

Either way, I'll be ordering the rings plain, and stamping them by hand myself, so I'm happy to take direction on how you'd like them to be stamped and which text you prefer.

Hey DaveP. Things are looking good. Please mark me as Interested.
Hey Dave. I'm in!
Thanks Guys. Much appreciated! I've added you both to the list. :)




**Update**

Time for another update to keep you all informed as to what's occurring...

This process (the process of organising who is to make each individual part, and trying to arrive at a final price) has, like every other stage of this project, proved to be much more time consuming than anticipated!

84 years.gif


We do now have quotes in for most parts. And the price is looking reasonable (I think), but not without a great deal of research, shopping around, negotiation, and a little bit of compromise (see below!). There are still a couple of things up in the air, but everything should be coming together VERY soon.

There is some bad news with regards to the balance pipe I'm afraid... It is with great regret that I won't be able to offer the balance pipe in accurate materials. :( The inner, Inconel part was not too much of a problem. Whilst still a bit pricier than more frequently used materials it wasn't too bad. The outer part is a different story however...

After months of research, discussions with veteran RR engineers and the RR Heritage trust, and after purchasing several vintage documents, and with no small amount of guidance and help from long time RPF members, whose help has been invaluable (You know who you are!) We finally have an alloy designation for the outer part.

What I can tell you, is that this alloy is no longer widely used, and although it is still possible to purchase in bar form, the price for the material alone is astronomical. So much so, that having the alloy forged actually works out cheaper! I was prepared, as I'm sure many people on the interest list were, for the price to be higher than if we were to have it made from standard steel. It's just not looking viable though unfortunately. The price for the materials alone is coming in at £300. That's before the machinists fee. So best case scenario, we're looking at £400 for the emitter alone! :eek:

I'm sure there are some on the list who would be willing to pay this. I think I might be if I had the money. What you need to understand is, that this price is the unit price for X 100. As people drop out due to the above high price, the unit price increases exponentially. If we were to only get say X 20 made for example, the cost for each one would be in the thousands.

It has been suggested that I do a fully Inconel emitter as an alternative. Interestingly, the Inconel used by RR would not have been the grade that is most widely used today. 718 was not introduced until 1964. I did consider using the earlier Inconel 600 to have a 100% Inconel emitter manufactured, but whilst I like the idea of at least the inner part being correct, the additional cost of doing that might not be worth it, knowing that the outer part would be incorrect still. If we can't go for full accuracy on the materials, we had might as well go for a cheaper alternative all round.

So... That's the bad news out of the way...

The good news...

The good news is, I've had the emitter priced up (still in two parts) in both mild steel, and in stainless and I've managed to negotiate a very reasonable price for either. I say either (rather than both) because we do need to decide which one to go for...

There are advantages and disadvantages to both...

Mild steel is ever so slightly cheaper. It is also easier to weather. The down side is, it is very different to the actual materials used by RR. The actual prop weathering is a combination of heat discoloration, carbon build up and dirt. There would have been no actual rust.

The advantage of using stainless steel, is that it actually very closely resembles the super alloys used on the vintage part. A new stainless Balance Pipe will look and feel very much like a new and out of the box vintage part.

The down sides are that, like the vintage part, a stainless Balance Pipe will be resistant to corrosion. That's not to say that it can't be weathered however. It will just require a different approach. There are products available for chemically weathering stainless steel. Not to mention paints and powders.


Personally, I'm leaning towards the SS for the reasons stated above. Also, there are very good mild steel replicas available already. It would be nice to take a different approach. If only to keep this offering distinct from others.

The balance pipe will be 2 parts still. There are a couple of reasons for this. Firstly, there is a detail on the inner part of the assembly that is impossible to machine as a single piece. I would like to include this detail, so that structurally at least, it will be identical to the vintage part:

4.jpg


The other reason, is that due to the function of the original part, and where it sat within the engine, the inner and outer parts ended up looking quite different after use. Separating the two will allow for different weathering techniques to be applied to each part.

I realise that it is disappointing that we can't go ahead with the super alloy pipe. But I am still very excited about having what will be a very fine alternative, at a much more affordable price!

All the other parts are coming in within a price range that I had loosely in mind...

All except for one... :rolleyes: I'm currently shopping around for a better price on the sheet metal work for the clamp. The lever is fine, but the cost of having the actual clamp and bars made is higher than I would ideally like at this stage. I have **considered** the possibility of sourcing a third party clamp. The whole point of this project for me though (as with all my previous ones) was the challenge (It's certainly been that!) Of researching the parts for myself and the satisfaction of having my own design realised. From computer screen to physical reality. So, I'm determined to find an alternative manufacturer that can produce them at a more reasonable price for us if I can.

Please bare with me just a little longer while I get everything ironed out.

I have another update planned regarding transistors, but that's a whole other subject so I'll leave it there for now...

I was going to tag it on to the end of this, but I think it deserves an update all of it's own, and that's enough to digest for now. :D

It's my hope that I can get final prices in and secured well before the end of this month. I think it would be appreciated by everyone on the run though, if we then have another month before final cut off point (and date of placing the order!), so based on this, I see the actual date of ordering the parts as being DEC 31st 2022. That still makes it a 2022 run, right? :p

It was my hope that I would be able to take partial deposits on this run, but due to the fact that I'm largely using new manufacturers, full, upfront payment for the parts at least, will be needed in order to place the order unfortunately. I won't take any payments for shipping until the parts have arrived and orders are ready to ship out. Hope that sounds ok.

As soon as I can, I'll be posting the final prices and more details about the final design and finishes, etc.

Thanks again for your patience everyone!

All the best and MTFBWY,

Dave
 
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Foe Hammer

Sr Member
RPF PREMIUM MEMBER
I would pay more for the inconel emitter, but if it's absolutely not an option, stainless is my vote for the reasons you stated above.
 

ScourgiousJinx

Master Member
RPF PREMIUM MEMBER
As I understand it the spirit of this project was to create the prop as close to the original as possible so I'd prefer stainless steel.
 

ObiShane

Active Member
I'm pricing some Inconel 625 oversized for what we need at $31 per inch shipped. You'd need something like 2.5" inches of it total (accounting for material loss) for both pieces Which equates to around $78 USD Per emitter in material. The stuff I found was nearly 3" OD which is a lot more than what we need. Might be able to trim a lot of fat off that price if bar stock closer to size could be found. This is in the USA mind you, and I'm not sure what's available in the UK. Mcmaster and most traditional metal metal stores prices can be CRAZY with rare alloy metals.
 

ObiShane

Active Member
He also has Inconel 718 at 2.5" OD at $24.10 per inch shipped. Which is closer to our size and about 20% cheaper but a more "modern" Inconel alloy.

Looks like he's selling old bar stock stuff.. I don't know, could be an option maybe.
 

DaveP

Master Member
RPF PREMIUM MEMBER
I would pay more for the inconel emitter, but if it's absolutely not an option, stainless is my vote for the reasons you stated above.
I would vote for a mild steel that is easier to weather. I don't want to have to buy other chemicals to have to try to get stainless weathered.
I'd like to throw in my vote for stainless steel.
As I understand it the spirit of this project was to create the prop as close to the original as possible so I'd prefer stainless steel.
Thanks for the input everyone. I'll keep an eye on things and obviously take everyone's opinion in to account. I'm happy to go with the majority. (y)

I thought I posted interest, but I guess I forgot. Please put me down pending price.

Thanks

That's great. Thanks James. I'll get you added to the list now (y)

I'm pricing some Inconel 625 oversized for what we need at $31 per inch shipped. You'd need something like 2.5" inches of it total (accounting for material loss) for both pieces Which equates to around $78 USD Per emitter in material. The stuff I found was nearly 3" OD which is a lot more than what we need. Might be able to trim a lot of fat off that price if bar stock closer to size could be found. This is in the USA mind you, and I'm not sure what's available in the UK. Mcmaster and most traditional metal metal stores prices can be CRAZY with rare alloy metals.

625 was actually introduced after 718. I got my dates mixed up in the above post. 625 was introduced in 1964. Two years after 718.

The last modification to the Derwent balance pipe was 1952, so this rules out anything other than Inconel 600.

That said, I was getting a similar price for the Inconel, which wouldn't be completely unviable... It's the outer part that's the problem. One supplier has the alloy needed for the outer part and the cost for that made up the majority of the figure I mentioned. It was actually cheaper to have the alloy forged in the UK. :lol: Not by enough to make it viable unfortunately. :(
 
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DaveP

Master Member
RPF PREMIUM MEMBER
He also has Inconel 718 at 2.5" OD at $24.10 per inch shipped. Which is closer to our size and about 20% cheaper but a more "modern" Inconel alloy.

Looks like he's selling old bar stock stuff.. I don't know, could be an option maybe.
I appreciate you taking the time to look by the way. (y) It's just not looking like something that's readily available these days. I don't think it was particularly common 70 years ago either :lol:
 

thd9791

Master Member
RPF PREMIUM MEMBER
Is it possible to do a modern inconel inside and a stainless outside?

Thank you so much for all this work! My vote is for SS if it doesn’t work out, anyway. Navigating factory estimates and sourcing the labor and parts must be overwhelming, you should know we appreciate everything lol immensely

And there’s no rush or pressure. You’re very ethical in trying to make it affordable on top of just seeing if it can be done
 

Loneken

Sr Member
RPF PREMIUM MEMBER
Interested Dave ! Haven't been able to stop staring at my Luke v2 since I received it, so I think I'll need this one too...
 

CHS3CELL

Member
I'd certainly pay for the Inconel (upfront if needed - as you are proven/trusted). To my knowledge no one has done this to-date. Certainly not digging stainless....prefer mild steel if no Inconel.
 

DaveP

Master Member
RPF PREMIUM MEMBER
Is it possible to do a modern inconel inside and a stainless outside?

Thank you so much for all this work! My vote is for SS if it doesn’t work out, anyway. Navigating factory estimates and sourcing the labor and parts must be overwhelming, you should know we appreciate everything lol immensely

And there’s no rush or pressure. You’re very ethical in trying to make it affordable on top of just seeing if it can be done

Thanks Tom! So, it doesn't actually need to be modern Inconel. Inco 600 is still fairly widely used. Not quite so much as 718/625, but it is an option.

To be honest, Inco 600 has a very similar composition to the alloy used for the outer part. Much closer than SS in fact. Composition wise, SS isn't very close at all. It just happens to share some characteristics... So I think the closest we could get is a fully Inconel emitter with Inco 600 used for both parts.

I've just submitted a request for a price for this, so lets see what that works out at. (y)

I’d throw my vote behind SS

Thanks Nathan. Keeping an eye on peoples preferences, whist exploring the option of a fully Inconel one. (y)

Inconel or bust in my opinion. I don’t know if I would still take part in the run if we opt for steel.

No problem Nick. I understand. As I just mentioned to Tom, the Inco 600 is VERY similar to the outer alloy, so I've requested quotes for an emitter that is made entirely from this.

Hopefully the price will be within peoples budgets/expectations. The problem is, if people start to drop out because the price is too high, it will push the price even higher. I think we need to try to keep it around the X 100 mark if possible for it to be a viable option.

If there are only a handful willing to pay for the Inco replica, we could end up in a situation where they cost the same as a genuine vintage one.

I've requested a quote anyway, so fingers crossed (y)

Interested Dave ! Haven't been able to stop staring at my Luke v2 since I received it, so I think I'll need this one too...

Thanks Charles! Much appreciated! Glad you're happy with it. :) I'll get you added to the list now. (y)

I'd certainly pay for the Inconel (upfront if needed - as you are proven/trusted). To my knowledge no one has done this to-date. Certainly not digging stainless....prefer mild steel if no Inconel.

I understand Greg. I'm happy to pay more for the Inconel one too within reason. Lets see what it comes out at and go from there.

I'll update everyone once I've received some more figures. (y)
 

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