to
ajb100 san,
brainfart san,
Warren san,
matthieutje65 san,

Thanks!
All of the advices are useful to me.
I will try it!

I would agree with all of the above! 

For thin cores, the filled epoxy works well. 

For much thicker cores, a neat cosmetic solution is to lay up a sheet of carbon then once cured cut it into strips to be bonded on the edges of the cored panel.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

1.Just spread some epoxy resin to the sidewall?

Some FILLED epoxy, containing for example lots of glass microballons and a black pigment.

3, Fillet the edge of the panel then add CFRP tape?

You will need lots of tape, that's potentially expensive and heavy.
You can bevel the core and connect the skins.
Have a look at the pictures in this pdf:
http://www.r-g.de/w/images/1/19/Herstellung_eines_Trickskis_in_Wabenbauweise.pdf

Pictures 2 and 7-13 should give you some ideas. Can't hurt to look at the rest of the pictures, too.

Cut the core approx 15-20 mm smaller than it needs to be around the edge, then use a heavy 650 carbon to build up a solid edge for that size difference

I want to build a relatively thick CFRP sandwich  panel.
so I will use aluminium honeycomb or urethane foam as a core material.

but I don`t know how to manage the sidewall.
I mean,if a thick CF-CORE-CF  panel is made,
its side wall of the panel has no protection.
The core material of the side wall is exposed to the air.
To protect the sidewall from delamination, I think I need protect the sidewall.

Fore example,
If I use 10mm thick core material,how should I protect the sidewall?

1.Just spread some epoxy resin to the sidewall?
I think it is a good idea,but it is not suited fore honeycomb core because the sidewall of the honeycomb is rough.
One more problem.if the panel is under bending stress,the epoxy on the sidewall might be cracked.

2, Spread some silicon sealing or flexible adhesive?
its more flexible so there is no risk to crack.
and sealing will fill the gap of the honeycomb.

3, Fillet the edge of the panel then add CFRP tape?
Filleting the edge uniformly  may be difficult.
and,CFRP tape may be less flexible when I use this technique to thin core material.

4,add a square CFRP bar to the sidewall.
it is useful when I build flat and square sandwich panel.
but, it is useless when I build rounded ore curved sandwich pane.


Is there a good idea to protect the sidewall of the sandwich panel?

Thanks,
hietaka