Degaussing for Al-backed insulation?

[m100psi]

Hi all,

I'm currently getting new insulation installed in my '78 J.  The shop doing it is concerned if they use the aluminum-backed insulation, they'll need to degauss afterward which in the past they've found to be time consuming.

Just wondered what experience others have with this?  Is degaussing typically part of the process when you carry out SB208?  Or do others use another type of insulation without aluminum?

Thanks,
Matt

[Guest]

It must be special aluminum if you can magnetize it. It’s also the wrong material to use.  Look up SBM20-208 

[PT20J]

I'd ask them why they don't have to degauss the entire aluminum airplane  Clarence is right, aluminum is not ferromagnetic. 

[EricJ]

Why would they think degaussing would be necessary?    Tell them not to use electric tools when they put it in. 

[ArtVandelay]

We’re surrounded by a steel cage, the non ferrous metal backing of the insulation is the least of your worries.

[Greg Ellis]

Maybe time to find another shop....

[Mark89114]

Plastic screwdrivers only will help.

[LANCECASPER]

22 hours ago, m100psi said:

The shop doing it is concerned if they use the aluminum-backed insulation, they'll need to degauss afterward which in the past they've found to be time consuming.

"Intelligence has its limits ..  unfortunately Stupidity doesn't" Albert Einstein

Either they really are that stupid or they are trying to degauss your wallet

[m100psi]

Thanks all for the feedback. A MSC found the insulation kit associated with the SB…for $750. 

[PT20J]

14 minutes ago, m100psi said:

Thanks all for the feedback. A MSC found the insulation kit associated with the SB…for $750. 

If you are taking the entire interior out, you might consider replacing all the fiberglass with this foam. I bought it from OasisAero, the MSC in Willmar, MN that had a quantity of it in bulk. Even though Mooney replaced the side panels with foam, it continued to use fiberglass in the ceiling and baggage compartment. The foam is much better insulation for noise and temperature.

 

[m100psi]

Thanks for the tip. I’m not planning to remove the ceiling panels, but I’ll call them to see if it’s a more reasonable solution than the kit. 

[carusoam]

Putting in proper insulation can’t possibly require degaussing an airframe…

Unless the shop intends to bring the industrial vacuum cleaner into the cockpit to clean up after the work…

Large electric motors have been known to magnetize things nearby….  
 

 

If you have done compass turns… and there is a heading that the compass hangs on….rests a moment… then accelerates to catch up… this is a sign of a magnetized cage…

 

PP thoughts only, not a mechanic…

Best regards,

-a-

[larrynimmo]

Perhaps an extensive use of steel fastners to reattach your interior panels

[A64Pilot]

Only thing I’ve ever seen to magnetize a 4130 airframe is welding, and yes De-gaussing is a pain, but if you can access the tubes it’s not that bad. You use a big electromagnet and just move it around and use a little cheap needle gauge to verify the lack of magnetism. Gauss meter maybe?

Looked just like this https://www.bergeng.com/product/MF-2480.html?gclid=Cj0KCQiAi8KfBhCuARIsADp-A55fbOKEXnqbWdHNdqRx5nKdGaCdApBzqwcJuHlUk9SDbS4cKFzc5dUaArGPEALw_wcB

This meter and the fact the compass won’t swing will tell you if de-gaussing in needed, but without welding I’d be real suspicious.

We had to de-gauss maybe 1 in 10 aircraft we manufactured when I couldn’t get the compass to swing