How tight is the thread done up ?
How is the rifling in a barrel made? I'm imagining similar to single point threading but moving the toolpost drives the spindle rather than the spindle moving the tool?Well, I have had an opportunity to see the actual tool used for removal and replacement of these barrels:
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Quite a thing and so I am going to try to get one, meanwhile I will be continuing with my own version.
there must be some established system for cutting rifling, maybe it would work for "External rifling
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The nut on the bottom adjusts the amount the tapered sections pull together and therefore expand.
The safety has a cutout to stop the nut coming loose in flight
I used to use the same sort of design for holding bar end mirrors on my motor bike, still do for the bar end weights, but instead of "O"rings I use pieces of rubber pipe which I found had more holding power.I have been doing this for a while you know, anyway, my interpretation, started with a bit of EN24 in the lathe:
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Machined one end down to 6mm and then bored it right through at 4.1mm:
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Then I made a series of collars from a it of Colphos, reamed them to 6mm and carefully turned the outside to 8.75mm:
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I had ordered O rings with a suitable size already and they had arrived in plenty of time, inserted into the piece of barrel and the threaded rod tightened up the mandrel was wedged firmly, this might just work you know!
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As soon as the replacement barrel arrives I will give it a whirl.
Was fitting set of blades last week here are the pins, long hold the blades x 2, short one holds the drag link
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Of the expanding variety.
This is the plot: I have a tube which s 6" long screwed into a block, it cannot, for any reason, be gripped on the outside, it MUST be screwed into and out of this block by being gripped internally. the bore is 9mm +- .15mm Is there anything out there "off the shelf"? Any idea as to how to make something, preferably out of brass as it is important that I don't mark the inside of the tube either.
Thanks in advance for any suggestions.
Can buy me a helicopter if you want…..Go on, tell em how much a set of blades cost! I almost went in with a couple of people on a part ownership of a helicopter, until I discovered how much the ongoing cost was, the replacement blades were eye watering and it wasn't optional. You reach a set number of hours, you replace the blades, doesn't matter the condition, with or without damage, you get to change the blades.
I can't begin to imagine the cost of blades for the Hughes 500 I was looking at a Robinson IIRC.
The penny has just dropped with me regarding your username! I should have guessed a hile back as I built a couple model 500's The Ferrari of the Heli world. You are right, I wouldn't like to buy replacement pins, many people don't understand aircraft spares or how you need a certificate with everything, no certificate, not worth a carrot.