Left Hand Threads?

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jthompso
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Left Hand Threads?

Post by jthompso » Wed Aug 02, 2006 10:21 pm

On the Kamps engine both the turbine and compressor are held on by left hand nuts to counter. This makes sense for the compressor wheel which turns clockwise when looking at it straight on, but the turbine wheel turns counterclockwise when looking at it straight on so a left hand nut would be tightened in the direction of rotation. This makes me wonder how essential a left hand threaded shaft is to the safety of a model gas turbine. Would some sort of lock washer and checks now and again be sufficient?

mk
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re: Left Hand Threads?

Post by mk » Thu Aug 03, 2006 12:06 am

Besides I'm not an expert in those turbo jet engine fields, the following should be valid somehow. While I can only hope that it is not as late that something got sense twisted.

I would be pretty much afraid, that you would never know when the nut has become too loose. Which means never early enough, so that you could shut down properly. Once the single nut is loose, it would be off. Considering the dangers involved, I would not like to stand next to that engine.

Using some kind of secure liquids seems to be pretty much affected by surface properties. However, even if that stuff would hold up, I think it would be that tight, that you would get difficulties when you want to take the drive apart.

Remember, the turbine is not only spinning, but also torque is acting on it. The left threads make sense in either case to me.
mk

jthompso
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re: Left Hand Threads?

Post by jthompso » Thu Aug 03, 2006 1:32 am

For a truly safe system wouldn't the compressor nut have to be a left hand and the turbine nut be right hand?

Mike Everman
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re: Left Hand Threads?

Post by Mike Everman » Thu Aug 03, 2006 6:35 am

No, the compressor is being driven by the shaft, the turbine is doing the driving of the shaft. I'd be very surprised if any engineer blew that one.
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jthompso
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re: Left Hand Threads?

Post by jthompso » Thu Aug 03, 2006 11:12 am

Alright thanks, I guess I'll get the tap then

skyfrog
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re: Left Hand Threads?

Post by skyfrog » Thu Aug 03, 2006 5:05 pm

Hi you have kamps' book that's good but be sure to understand everything before you set off making and testing your own turbine, that's my sincere advise.
Long live jet engine !
Horace
Jetbeetle

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