Laminating problem ?

Last evening I poured acetone between plug & lamination and left it to soak over night & hull just fell off the plug this morning… but one hell of a gooey & sticky mess to clean up today.

I’ve used plastic for rudder lamination’s and done deck lamination on perspex & glass and never had problem not using wax, this is why never thought about using wax on plastic packing tape, but thinking about it they were relatively flat surfaces that easy access & could peel by hand.

The form of the hull shape lamination encapsulating the plug, does not make it as easy to help the release by hand, so wax would have helped considerably … another lesson learnt !

Hi Alan,

For some reason, the epoxy seems to adhere quite well to packing tape without a couple of coats of wax.
Glad to hear it all came apart without much fuss.

It is one thing that I like about composites - You never stop learning!
Cheers, Jim

Did you by any chance use a new or different roll of packing tape? I’ve heard of a couple of cases now of epoxy sticking to packing tape.
Don

Hi Don,

This was the first time I’ve ever used packing tape, it was new roll. For the 3rd plug I will use latex over the plug, laminate and then latex again over the top … its the only thing I really trust now.

Packing tape is good if you’re not going to re-use the plug again, one way or another the packing tape will age & crack and it’s an ugly job to get it all off again, but had to try it for the experience.

The way things are shaping up looks like I will get into some vac gear sooner than later, if I continue making hulls at this rate.

Cheers Alan

I’m thinking that a person should do a test run with whatever packing tape they are going to use and then mark the roll as “good”.
Don

I’ve only used (and will only use) 3M brand tape. Never had a problem, but I do remove the tape if I don’t plan another hull right away. Since I hate wax (never can verify if I missed or not enough) for layups with strange shapes, I have used tape with a very, very light spray of WD40 - just a mist, don’t drown the plug. The glass tends to want to wander around a bit, but a bit of masking tape will hold it in place until epoxy cures. I have not found the WD40 to adversely effect any subsequent layers of glass.

ummmm - use at your own risk - since I’m not there to see your spray technique.

Out of interest I wanted to find out why resin adhered to the packing tape, the membrane surface of the tape I used is cellophane which is based on plant matter [cellulose] that has been regenerated from wood or corn that is NOT in the plastic family… it breaths ! hence the reason why wax or Dicks WD-40 stops it from breathing.

Plastics on the other hand are synthetic or semi-synthetic polymer that is Petrolium-based.

Many people mistake Cellophane for plastic like me :rolleyes: The truth is the two substrates are of completely different composition. The only thing they have in common is that both materials are can be manufactured as transparent film.

Why ? Cellulose can is bio-degradable where synthetics are not and most house hold packing tapes are made to be bio-degradable when disposed as we live in a green world right.

Don, also found out that cellulose tape is generally designed decompose in 30 to 90 days in a composite pile so the older the tape the more likely you to have problem using it.

Hope this is helpful to those considering using packing tape just beware of what you are using !

Cheers Alan

P.S Question how do you know which is what ? simple test is that if the tape has crinkling sound when you roll it in you hand it will be most likely be a cellulose based substrate and it does not stretch, unlike Petrolium-based plastic substrates.

Here is the tape I usually use, as it is the thinnest and leaves less of a ridge when overlapped.

http://www.uline.com/BL_3092/3M-302-Tape

1.6 mil and polyurethane based - not cellulose

Here is a list of most common 3M tapes if you have special requirements:
http://www.uline.com/Grp_241/3M-Packaging-Tapes

I seldom purchase the 3 inch wide tape - preference is for the 2 inch wide.

For those overseas, I would guess most countries have similar products imported or available. Try wholesale outlets for manufacturing/warehouse products.

Dick