Bungee replacement with alternative

[NeilD]

I should have those in the morning.

could you let me know where to send them please

NeilD

[NeilD]

HI,
the 1080 of 5/8 diameter bungees give a csa ( looped) of 395 mm2
the rings have a csa of 660 mm2
if we tried the 1380 bungees at 13/16 diameter, the csa would be 669 mm2

The 1080 will just fit in the spool. If it has a higher strength and modulus compared with the neoprene rings, we should be close on performance. Alternatively we will have to go with the 1380 bungee, but this will not fit into the 30mm wide spool.

I'm contacting a rubber company again to confirm the pricing on ring replacements, and subsequent pricing once the tooling has been paid for.

[Neil Spooner]

........looks like NK&C will have some genuine bungees soon.......!!

[NeilD]

The 1080 HD bungees have arrived

[Neil Spooner]

Just an update on u/c bungee test:
I have set up my spare fuselage to do the test, I needed a pulley to half the load on the electronic strain gauge (50kgs max, so I can now measure 100kgs) which I got yesterday and machined out to fit the u/c axle. I hope to do the test on the HD1080 bungee later today. (work keeps getting in the way!) I am short of the inner ring of the nose leg spares that I have, so am awaiting the kind loan of a main half set from Gary to do the Niemen test. I will progress as soon as I can.
I intend to video the replacement of the 1080 with the Niemen rings and post it on youtube to assist in the understanding of the use of the u/c tool. Fitting of the 1080's was easy with the tool.
NeilS

[NeilD]

looking forward to a positive result!

NeilD

[Neil Spooner]

Hi Guys,
I have at last done the load test on the bungees, and have yet to plot the results on a graph to check compatability, but the results look similar.
I have also done a video of me using the tool to remove the Hd1080 and replace it with the Niemen rings to show how to use the tool which only takes about 20 min's.
I have uploaded it to my youtube channel: http://www.youtube.com/user/goncstube#g/u
This is the u/c video: http://www.youtube.com/watch?v=0bf6xhwFS_g
Thanks to Gary for the loan of the Niemen rings to do the test.
The most difficult bit is lifting the a/c and tresseling it, that is also the most dangerous part and most likely to do damage to the airframe. When I changed mine I suspended the a/c from the door frame (you could use an engine crane )using the cross-tube behind the seat, but beware, you will need to support the wing tips as it will tend to tip over.
Neil

[NeilD]

Very interesting watching the video.


NeilD

[Neil Spooner]

Hopefully makes the job a bit easier knowing what you are up against. The tool is very easy to use, just keep it straight and oiled, keep eyes and limbs clear of potential "missfires". I wanted to get over to the hanger again today, but had too many domestic issues to resolve. I am putting a Lambda sensor in the port side of the exhaust to check mixture distribution.......another story!!

[NeilD]

What's the next step then?
I'll fill out the mod1 proposal form when you have the compared the deflections.
Did you get some still pictures of the deflection test?

Cheers

NeilD

[Neil Spooner]

Hi NeilD,

I have posted two personal emails, which are still sitting in the outbox on this site......I assume they should automatically send, but they haven't. Sorry if you think me rude. Please email your personal address to: neil@spooner60.orangehome.co.uk and I will send you all the details of the mod'; the LAA forms; photos; load graph etc that just need your details on. All tests done.

NeilS

[NeilD]

Hi,

I've sent a private message......

Checked my nipper today, got the brakes working finally

couldn't fly due to the hangar doors stuck fast, as the ground has risen due to the frost!!!!

[microlightgary]

Well, heartfelt thanks to Neil for developing a great bit of kit which will make everyone's life easier Used his excellent U/C tool today and have replaced the rubbers (did the nose too while I was about it).
That means good news - KI is almost ready to be re-permitted! Am really chuffed - just a couple of small issues to sort out and I can get my inspector over. She should be back in the air for March (or maybe even a little earlier) if all goes well.

[Neil Spooner]

Hi Gary,

Great news and well done!! Pleased the tool worked for you. We are much closer to finding an alternative, NeilD has been financing the cost of purchasing the replacement bungee, and I have now tested the STD 1080 which appears much closer to the original. The only downside of the replacement bungee is that use of the tool will be mandatory I think, as the bungee is much harder to work with, however, with the tool just as easy to fit.

Look fwd to seeing you in the air soon.

Neil

[microlightgary]

Thanks Neil - PM sent.