Hello!

I have a question about  sandwich core technique.
That is...

For example,
If I use  two set of  5mm nomex honeycomb core(10mm thick in total) to  make a sandwich panel,
is it  as strong as  a single 10 mm nomex honecomb core panel?
the  double 5mm sandwich has reasonable strength?
or the double 5mm sandwich is easy to break?


actually,
I want to build a curved sandwich panel.
I tried a 10mm thick  nomex honeycomb core at first,
but the 10mm thick core was too strong to bend.

 I wonder that if I use  a 5mm core,then laminate,bend  and add one more 5mm honeycomb core.
I mean,,  the sandwich is   CFRP>honeycomb core(5mm)>CFRP>honeycomb core(5mm)>CFRP.
If this idea is O.K. I will be able to build thick and strong curved sandwich panels.


Any advice,
I would be happy.

Thanks,







 

What grade nomex are you using ?

Are you aware of the OX/Flex core,s ?

Is the orientation critical on your core ? one plain will have a LOT more flex than the other, can you make that work for you ?

When you say cfrp are you talking wet lay or pre preg ?

Have done double cores a few times with pre preg and it gives you a very strong laminate but I use a inter laminate ply of carbon with a film glue either side between the cores

>f1rob san,

Thanks for asking!

>what grade nomex are you using
commercial grade. maybe 1/8 inch cell 1.8 pcf( I might change the grade)

>Are you awaer of the OX/Flex core,s?
sorry I dont understand.

>Is the orientation critical on your core? one plain will have a LOT more flex than the other, can you make that work for you?
well...I have not purchased 5mm core yet. but I think the 5mm core is flexible so it will work well.

>when you say cfrp are you talking wet lay or pre preg?
I would use  wet lay and vacuum bagging technique.

Not sure which one 1.8pcf equates to as all the work I have done with Nomex used 29/48 or 64 grade

29 being VERY soft and pliable 48 being the standard default core almost and 64 mainly for flat sheets/light curves

Mainly used in ALI cores but also avalible in Nomex you can get over expanded cores or flex cores which aren't hex cells but various shapes designed to aid flex

Looking at your sketch rather than separate front and back legs cant you incorporate them into a single piece ?