The 'Ideal' Obi ANH Derwent Interconnect Replica

[Darth Lars]

<div class='quotetop'>(Serafino @ Jul 17 2006, 06:22 AM) [snapback]1282238[/snapback]</div>

Darth Lars--plating what with what?
[/b]

That is a very good question ...
The point is to use a relatively cheap, machinable base metal and then plate it using
an alloying metal and process that produces something close to Inconel.
I read that Inconel consists of 50-75% nickel. Maybe some type of nickel-plating - there are several processes, which I admit I know nothing about.
I don't mean to suggest or vote, but to inquiry.

 

[damon5973]

I see it 2 ways.

1- Are we building an AFBB or a weathered version.. Depending on builder that is going to make the difference. If the iconel can be made to look weathered easily(I need a weathered one) then I say go for that and see below. If another material will "age" better to make a weathered version go for that.

2- which is most accurate and does it matter what the material is? Since it was stated that these will be machined and not acutual engine parts does it matter what the material is? I am all for 100% authentic BUT since they are not "real" and each persons definition might vary... I would want what looks best.

Now price is also a factor. reasonable price would equal more interest. Higher price may be a bit hairy. I think I could manage the iconel material but the weathering would be a factor for me.

SO- What ever will look best weathered is the one I want.

 

[Dagobah Don]

<div class='quotetop'>(damon5973 @ Jul 18 2006, 12:53 AM) [snapback]1282781[/snapback]</div>

SO- What ever will look best weathered is the one I want.
[/b]

Yes, what he said.

And I vote Inconel.

 

[skywalker86]

i vote for inconel, but if there isn't enough interest in using that material, steel is a great secondary choice.

 

[Prometheus]

Oh Inconel of course.

 

[Serafino]

Prometheus quit gloating.

Darth Lars--I will look into the options, but from what I can tell nickel plating would look nothing like Inconel, strange as that may seem.

Damon and Avalon--steel is more easily weathered by the means available to us, the original was Inconel 'weathered' by being put through use in a jet, then perhaps colored somehow by the prop dept. (I'm not using the evil word 'paint', but I think it's a possibility).

I think I'm seeing a trend here (Inconel AND steel.), but please keep the ideas coming.

 

[dcarty]

<div class='quotetop'>(Serafino @ Jul 17 2006, 10:32 AM) [snapback]1282436[/snapback]</div>

dcarty--I haven't identified that effect yet, but not all interconnects share the pattern. I would plan to have the face area bead-blasted (the ring of holes area at least for sure), it would not be a problem to have some blasted all around. I have some additional research going on that may provide the answer as to what the effect is on the originals.

[/b]

Thanks Serafino,
I'm curious about the finish (let's call it "beaded") and that not all interconnects share this feature. I wonder if the interconnect may have been cast and then machined to specification.

Cheerio,

Dave C

 

[Serafino]

I don't see evidence of casting, FWIW. The matte finish does not say 'casting' to me, I'm more inclined to think it's oxidation--particularly since on my example it exists on the very area that you would not bead-blast because it's to pressure fit into a hole.

But IMO that matte texture is present on the prop ring of holes and probably the surrounding flange 'face' as well. I'm not sure about the outside of the prop interconnect, that matte 'grey' effect doesn't seem to be present in the worn areas, so either the dark/blackish color is the matte stuff, or it's so well bonded to the matte stuff that the two wear off together, or the prop interconnect is one (like others I've seen pictured) with a smooth satiny exterior finish.

 

[lonepigeon]

My original balance pipe (wrong side one) is really dark except for the top which has that bead blasted looking finish. It's actually a metal coating and there are different variations of coatings. My old contact at the Duxford museum mentioned this to me before. There are many balance pipe part numbers and I believe many are the same pattern just different coatings.

 

[Serafino]

It would be very cool if we could find out just what those processes are. I have some information coming to me which may just possibly include some of these specs but I won't know 'till I see it (and I'm not holding my breath )

 

[franz bolo]

I did a lot of research and finally got a hold of an original blueprint for the interconnect.

I'll get Serafino all the specs. I'll try to find out more about the piece if I can.

I'm not able to publish the full size blueprint so sorry for the small image.

FB

 

[ATL Kenobi]

FB - Very impresive indeed :thumbsup . Finding the interconnect drawing must have taken a lot of time. Thanks for the effort. Does the drawing specify a finish?

ATL

 

[Ghost Host]

FB, Is it a permission thing about the blueprint, or just that you can't host a large image? I'd love to see that print large enough to read.

 

[Serafino]

It's a permission thing.

 

[Serafino]

On the subject of color, IÂ’ve just gotten a chance to see an example with a perfect translucent slate-grey/black color on the small tube. I will be taking some photos in sunlight to see how the color compares to booster color in low sun light, it will be interesting to compare it to this picture:

Just for interest's sake for those who haven't seen them, here's a set of Screen Caps.

 

[Yorpheus]

1st choice: Steel
2nd choice: Inconel (off-shore price)

 

[Darthmagpie]

Just a little input here. Inconel is a trade name for the material with the specified material composition and inherent characteristics. Did your material source specify "Inconel" or the material with that composition? What does the Blueprint callout for material? You can buy material with the same composition that doesn't use the trade name and mostlikly at a better price. I also believe you can heat treat the material to soften it making it easier cheeper to machine. Unless you know the material composition of the original parts ultamate accuracy may be blurry. for instance to say Stainless Steel. What grade? Just in 300 series there is 303, 304, 316, 316L, 316L VAR and 316L VIM VAR(to name a few). Inconel is getting more difficult to get due to the semiconductor industy demand.

I also wanted to point out that although inconel does not oxidize "gray" that may be true in an inert environment. But an engin is hardly an inert environment. When differnt gasses are "burned they embed oxided into the material(sulfer = Brown; oxygen=blue; manganeese=black). the only way to remove these oxides are to bake the part out in an inert environment under extreem high temp(or removing the material that contain the oxides) The variation in color can be atributed to the gas chemistry used on the engin and in what environment and the time in sevice.

I hope some of this usless info I have rolling around in my head offers some insight. Ben

Also if there does seem to be a coating on it , it may be ceramic which is used in high heat aplications.

 

[Serafino]

Ben thanks for the information--the oxides/color info is especially interesting. I'd really love to be able to put a plausible dark oxide color on an Inconel replica.

The information regarding material came initially from an engineer involved in rebuilding and flying the engines, and has since been confirmed from other sources. I will check into the possibility of annealing inconel and sourcing the same alloy elsewhere. Hopefully I'll know what the blueprints say tomorrow.

Do you know whether ceramic coatings such as you mention would have been used in the late 1940's/early 1950's?

 

[Darthmagpie]

If not previously guessed I work with inconel. I have scrap inconel at my disposal(sorry no bar stock big enough for the emmiter) that can be used for testing oxidation runs and possibly access to a very high heat furnace. If you want to work with me on this i would be happy to lend a hand.

 

[Sporak]

I vote for steel...as noted earlier, this is a replica...and if the weight and general feel is the same, we can weather it to match as we see fit.

I have a authentic, but wrong model/type interconnect so I can see what the weathering is and feels.

I'd rather get 2 in steel than 1 in the other material.

I just want something more substantial than aluminum.