Nostromo Self Destruct Bolt

[Dean O]

Started this model today while it was slow. I modeled this based on the Prop Store auction pictures from last year. I will probably 3D print it first to see how the dimensions look in hand before trying to machine anything. I can definitely make it on my manual lathe at home, but I may try to set this up on the CNC lathe at work.

The auctions pics show the details really well but if you spot any glaring inaccuracies in my model please point them out!

 

[flimzy]

Started this model today while it was slow. I modeled this based on the Prop Store auction pictures from last year. I will probably 3D print it first to see how the dimensions look in hand before trying to machine anything. I can definitely make it on my manual lathe at home, but I may try to set this up on the CNC lathe at work.

The auctions pics show the details really well but if you spot any glaring inaccuracies in my model please point them out!

View attachment 1875466

I actually have one I was given years ago from a friend who worked on alien if your missing any dimensions

 

[septic]

Very interested in how this turns out.

 

[Dean O]

I actually have one I was given years ago from a friend who worked on alien if your missing any dimensions

Thanks! That would be awesome! I’ll reach out via PM to chat more about it.

 

[Ottostudios]

I don't remember where I got these photos from, but I know they are correct.

 

[flimzy]

CAD drawing

 

[flimzy]

I got these from Bill Person years ago , I honestly didn’t think they where real, I thought he’d made it in his work shop, I never thought to ask.

 

[Dean O]

Thank you both for these. My dimensions were pretty close already but I can make adjustments and get them even closer.

 

[Pro Mod]

I got these from Bill Person years ago , I honestly didn’t thing they where real, I thought he’d made it in his work shop, I never thought to ask.View attachment 1875649View attachment 1875650View attachment 1875651

R B Replicas produced these a long time ago and you could buy a plaque signed by Bill to go with them. I'd guess Bill received a few of these as part of the deal. I've got four of them and they really are a good replica.

 

[Birdie]

 

[Dean O]

Updated my model this morning. My original dimensions were only .010-.015” off just scaling from an image. But I really appreciate the help getting it as accurate as possible.

 

[Sidewinder]

Is the threaded portion a standard size eg M32?

 

[Dean O]

That same question that came to my mind earlier. Hopefully someone knows the answer. I can make the thread to any dimension but I’d like to know what is correct.

 

[Sidewinder]

That same question that came to my mind earlier. Hopefully someone knows the answer. I can make the thread to any dimension but I’d like to know what is correct.

I think it might be 1 1/4-7 UNC. Would make it 31.7mm OD and 3.6mm pitch approx Or 1 1/4-12 UNF 2.1mm pitch?

 

[Dean O]

Yup either of those are really close. I measure somewhere between .100-.125” between threads, that makes it 8-10 threads per inch. Or 2.5-3.5 metric.

Edit:
Also counting the threads on the props there seems to be 10 or 11(accounting for the chamfer on the end) within the 1.1” 28.18mm length.

Edit again:
I have a 1 1/4 - 8 and 12 tap here at work and the threads are either too fine or too coarse. So I’d say either 1 1/4-10 or metric

 

[Sidewinder]

Makes it 1 1/4 UNS then?

 

[Dean O]

Yup or M32 x 2.5. I’ll take a look in my shop at home and see what size large taps I have to compare.

 

[flimzy]

I never thought to ask, Do you want my cad model it has the knurling and thread on it. IO think its a 2mm pitch

 

[flimzy]

I think it might be 1 1/4-7 UNC. Would make it 31.7mm OD and 3.6mm pitch approx Or 1 1/4-12 UNF 2.1mm pitch?

I agree with this as Metric thread weren't popular back then.

 

[flimzy]

I agree its Imperial as Metric thread weren't popular back then.