Peel ply question and BJ24 update

[Hugh M.]

Is peel ply reusable? Could I buy enough for just one full stitch & glue keel joint and use it again on the chine joints?

BJ24 update: after the bottom panel snapped I have the boat back to the same point I was before starting work on that fatefull day.

I was worried that the panels would not be symetrical due to the new scarf not having a match on the other side. I am happy to find no apparent difference in the lines, at least to my eye. Good enough.

I spread some epoxy "insurance" on the outside of the curvey bow sections. I also added a few strips of 'glass tape near the chine edge from the bow back about 4 feet.

-Hugh

[Wild Wassa]

Peel ply will absorb some resin, so if you can keep it free from contamination it could be re-usable and still achieve the real benefit, the porosity is important. If you look at how rigid the storage instructions are for peel ply (for gel coats and v'bagging) you can see what you might be up against with any form of contamination.

So I use a nylon shower curtin or I did until it became too grotty, then I went really high tech and cut up an old nylon tent fly.

Warren.

[ 11-08-2004, 04:53 PM: Message edited by: Wild Wassa ]

[John of Phoenix]

Hmm, I never thought to try reusing it because it was so stiff after the first time. Try it on a scrap piece of plywood and see.

The best price I've found was direct from the manufacturer. The only surprise is that it's available from them at all. The call it "Econo Ply J". They charge $47.25 for a 60" x 25 yd roll plus shipping.

https://www.airtechonline.com/airtechstore/product.asp?ProductID=12&Dept_ID=5

[Mike Vogdes]

I use a material called tapan, it is used as dress lining and can be purchased at any fabric store. It is made of the same material as peel ply but at a fraction of the cost. I think it cost me $1.50 a yard the last time I bought some.

[NormMessinger]

Interesting question. I used quite a bit of peel ply on my Long EZ airplane as I was building it. Never considered it reusable. Given its purpose in this application, i.e. to insure adhesion of subsequent layers of glass, it would seem stupid to risk reusing it. Some used dacron fabic from the local cloth store to save a few bucks. Unknown sizing in such fabric also begs a risk for the little one would save. On a boat, who knows.

[capt jake]

Mr Teetsel's recommendation seems pretty good to me. I just priced some differnt fabrics from the local fabric store and it appears as though they would be more expensive than buying the 'real' peel ply. Peel ply is available in much wider widths than most conventional fabrics.

[JimConlin]

I use the same stuff and it works just fine. At $.13/ft^2, i have no urge to re-use it and i have no confidence that the weave of used peelply is still open enough to be adeuqately permeable.

[Tom Lathrop]

Peel ply or one of the substitutes is definitely NOT reusable. The function is completely lost after the fabric pores are saturated with epoxy. If the fabric is not saturated, you need more epoxy on the glass tapes.

Any closely woven (sheer) synthetic materal with a slick shiny finish will work. I found dress liner material at a cheap price. Anyway, the cost should not be a big factor when you measure the small amount you will be using on the interior chine and keel of this boat.

I would not make a structural joint over cured epoxy even if it was done with peel ply. A freshly sanded surface will be stronger.

A well made scarf joint will not cause any unfairness.

[ 11-08-2004, 10:41 PM: Message edited by: Tom Lathrop ]

[capt jake]

So Hugh, I know that you are all stitched together. Have any progress reports and/or photos??

From what I saw, you are doing a fine job of putting her together. smile.gif

[Hugh M.]

I layed up the keel seam with a fillet and glass. One word of advice - I found that the bi-axial cloth must be layed in dry, then saturated. If it is pre-wetted out, once you pull on an end the fibers want to go straight and you loose about 50% of the tape width, plus the edge gets all curly - really frustrating to try and get it back in shape. Doing it dry works just fine though.

I laminated up some really nice doug fir for the inner stem and have finished shaping it. The fir was out of some old 2X10's and is over 50 rings to the inch! Once the stem is in, I'll complete the chine seams. I am also ripping out some of the same fir for the inner gunnel.

Stem, seams, gunnel, bulkheads! That is my goal for the Christmas break.
-Hugh

[capt jake]

Sounding great. Remember to call me when you need a hand turning her over. smile.gif

[Tom Lathrop]

Hugh,

I could not believe that I did not tell you how to cut the biaxial cloth to avoid the stretch problem but I looked at the instructions and it was not there. Bummer, must have written it somewhere else. Anyway, the best way to cut biaxial is parallel to the thread lines so that the knitting threads resist the stretch. Buy a carbide dressmakers cutter for this job. It's a little rolling disc that actually breaks the glass fibers instead of cutting them. Works great as there is no tendency for the material to wander about while its being cut.

Cut this way, the biaxial tapes can be prewetted easily. I use a sharpie pen to mark the lines and a piece of masonite works well as an cutting board although plywood is ok too.

[ 12-07-2004, 07:15 PM: Message edited by: Tom Lathrop ]