Talk Composites - The Forum for Advanced Composites

To core or not to core

http://www.talkcomposites.com/Topic4410.aspx

By FLD - 1/21/2013 10:30:08 PM

I'm wanting to make this 3 vent bonnet for my waggon.  To date everything I have done has been wet lay.  Perusing this forum has got me thinking about having a go at infusion.  I'd appreciate your opinions on if this is an ambitious moulding for a first go (especially given how comfortable I am with wet lay).

I'm also looking for thoughts on weight / strength of these two lay-ups. 

1) 200g / 650g / 200g wet lay with constant vac

2) 200g / 200g / 2mm soric / 200g / 200g infusion

My thoughts are that 1 will be lightest but 2 will be strongest.  Plenty of time to reply as I'm still sorting out the moulds.  The base piece of the mold is a horrible shape so might be tough to infuse.
By wozza - 2/12/2013 5:21:56 AM

Tricky shape that one! 
Using Soric would be the way to go normally, but laying the Soric won't be easy. The two "ribs" in the design will add massive stiffness anyway.
Did a similar bonnet for a custom car last year. If it's being left bare carbon be prepared to loose the weave in areas. I ended up doing it in plain weave as 2/2 Twill looked messy.
I cut some 18mm MDF the shape of the cut outs (less the stack thickness) and put them on top of the stack as I was pulling vac. This really helped in getting the cloth into the recesses. You could "loose" some of those "sharp" edges with body filler to make things easier but maybe that would detract from the look the bonnet has.
Good look. Did a lot of head scratching with the one I did so if I can give any advice just let me know.

Warren