Blister in the bag

Have been vacuuming several components and have noticed that where the suction cup attaches to bag and pulls down on the component i'm left with a raised blister.



Above is a picture of a rig attachment point i've bonded in under vacuum and you can see the 'hickey' on the left hand side of the panel.

Also had a similar problem sheathing composite bulkheads, any ideas why?

cheers

roger

 

You have moulded a partial impression of the hardware you used.If you use the standard type of vacuum fitting http://www.metyx.com/Uploads/GenelDosya/122013111123245.pdf and a pressure plate beneath it,the feature will go away.

 

Cheers wet feet, admittedly my suction cups aren't like the ones you describe so will try a home made pressure plate first then if that doesn't work i'll change to the ones you've mentioned.

Cheers

 

Keep the vacuum off the glass your bagging,lay some extra breather off to the side and bag around it.
I've read it here before, Keep the frog off the job or something like that.

 

The trick with keeping the fitting off the finished laminate is a good one, we use it all the time. We call that extra piece a tail! You can fix that blister by injecting epoxy into it or if it is a bigger one you can grind it out , feather back and scarf in more laminate. Looks like your into it pretty deep, hats off to you!............g