Iv laid up my 1st fuse with glass and carbon tow.
Results to post shortly.
I've basically followed this approach
http://aviatorstudio.net/bdwithjig/bdw_fuse.html

All good until I apply vacuum to my layup.
My dlg fuse is a lot skinnier than a bubble dancer so I'm finding at the very bottom of my mold the bag doesn't want to compress down enough. Almost like the bag won't stretch enough.
So I laid in some polyester as bleed cloth and filled the fuse with tissues and then bagged it. This helped but it caused some fabric bunching at the top where my joins will be. I had a few air voids which is my fault.
Maybe sand instead of tissues might help.
The bladder approach is beyond me at this point till I master my layup etc.

Any other suggestions.
I'm using vacuum seal bags as my vac bag. Fairly thick so maybe a different bag material might have a bit more stretch in it too.
I guess I could mold a silicone plug to compress into it also.

Using peel ply is a good step followed by some sort of relitivly thick breather. Unless you order up some of the very stretchy bagging material what you need to do is get multiple pleates into your bag. With the proper breather you don't need to worry about wrinkles in the bag as they will not transfer into the part. When bagging wings we want the bag nice and tight without wrinkles. With a fuse, just make the bag twice the size of the mold and get enough bag into the mold to eliminate bridging.

Yes that makes sense thank you.
I think I'm too hung up on not getting wrinkles.

Here's some pictures.
Layup was 3/4oz 45,3/4oz 90,12k tows, then 45 and 90 for some heavier glass I had. Not 100% on weight but probably 4oz.

Originally Posted by Tim Harbour

All good until I apply vacuum to my layup.
My dlg fuse is a lot skinnier than a bubble dancer so I'm finding at the very bottom of my mold the bag doesn't want to compress down enough. Almost like the bag won't stretch enough.

All you need is a bit of Stretchlon 200 bagging film. It is made to fix the exact problem you are having. It is a very flexible plastic film that stretches down into even complex cavities.

Tom

PS: The above assumes you are working with epoxy. I don't think Stretchlon is compatible with polyester resins.

I generally use .7mil plastic drop cloth from Lowes or HD in place of strechalon now. Just as much stretch and it's more compatible with the epoxy systems I use.

Both work well.

Thanks heaps guys. Yes it is epoxy. Wests systems.
I think I should be better armed for another attempt now.
I'll get a better bag material, good breather cloth and not be too worried about wrinkles while vac in on.

Originally Posted by Tim Harbour

Thanks heaps guys. Yes it is epoxy. Wests systems.
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There are superior and cheaper resins available for us NSW builders Tim.
I suggest you source out some Araldite LC3600 laminating resin. You will find it much easier to use, longer pot life, true low viscosity etc. (All resins seem to be marketed as "low viscosity" - some are, some not).
Alternatively, Tim (Timbuck) uses Kinetex, which he highly recommends.
Are you the Tim that I met at Borah during one of our Manilla Slope Festivals?

Anyway, welcome to composite moulding. You have embarked on an exciting and challenging adventure.

Thank you Jim.
Yes I did see you at Manilla a couple of times in the past.
I just changed my user name from TLHover to save confusion.
Sadly I didn't make it to Manilla this year.
I hear you with the Resin suggestions, I will be sure to use either of your recommendations in the future, especially after reading about everyone feeling the same way about wests epoxy.
It's kind of a double edge sword. You go cheap to start out with but end up creating more problems to deal with. LOL
I've been keen to try Timbuck's Liquid mold mix with ATH and resin on top of a gel coat. Quick and easy by the looks.

What are your thoughs on this process compared to your cloth/Steel frame layup??

I've built my fair share of balsa planes, now wanting to embark on another adventure/Challenge.

I don't get a lot of time to build but enjoy it when I do.

Originally Posted by Tim Harbour

Thank you Jim.
Yes I did see you at Manilla a couple of times in the past.
I just changed my user name from TLHover to save confusion......

I guessed so, but was not sure. Good to read your thread.
Sadly I didn't make it to Manilla this year.
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It's kind of a double edge sword. You go cheap to start out with but end up creating more problems to deal with. LOL................

Wests is not cheap! Compare the prices with LC3600 delivered!
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What are your thoughs on this process compared to your cloth/Steel frame layup??
.........................................

I have not tried it, but I like it. It would be a small fraction of the work of my method. However, the ATH is expensive to get delivered here. I might investigate getting some in the future, as I am sure to build another moulded glider. (not soon!).
I am likely to be driving to the city before that time comes, in which case, I will be buying a bag to give it a go. With transport (shipping) costs avoided, I understand it is cost effective.
Have you priced it lately? If so, let me know.