National Aeronca Association Bulletin Board

I'm about to start the priming process on my L16 fuselage (if I can ever string together a couple of days without having to run out and do something else). Anyway, I looked over all the tapes and they're all 'stuck down' like they're supposed to be. Normally, I iron the edges with a cool iron but after I primed the control surfaces (some time ago) I had a few of the pinked edges that popped loose on me and it's darn near impossible to get them to stick back down once you've primed the fabric. I'm thinking that ironing the tape edges loosens the glue some and allows the primer to penetrate under a tape edge. As the tapes and pinked edges are sanded anyway after being primed would there be any consequence to not ironing the tape edge, assuming everything is stuck down well before priming? Just thinking.......... .

This is my third cover job so I'm not exactly a rookie at it but the popped pink edges do bother me, no matter how few. Appreciate any info or ideas. I did talk to Molly at Superflite and she said it wasn't absolutely necessary to iron the tapes, but.............?????

Mike Berg

Mike, I've found pinked ears will lift (with PolyFiber) if I don't get enough PolyBrush on the tapes. Then, as I spray the first coat of PolyBrush, MEK and other volitiles will loosen any ear that doesn't have a good pre-coat of glue. And usually with my luck, they'll lift about the time I'm shooting PolySpray, the silver coat.

At that point, I'll try to iron them back down using some Parchment Paper. It's about the only thing I've found that won't stick or mar the paint. But you've got to use a lite touch with the iron. And let the paper cool off before you lift it off the silver. I'd give that a shot.

I never like sanding off the ears because it leaves a ragged edge thats just as hard to hide. But thats my opinion.

nkh

Nathan,
Sounds about like the same deal. I try to be careful when I glue the tapes down with the Superflite glue (U500) but you have to leave a strip slightly wider than the tapes or the pinked edges won't stick down. I actually use a 2' level that's 2 1/4 inches wide and center it over the stringer or whatever to draw the lines which allows me a bit to go on when I lay the tape. I'm going to prime the bottom first where things don't show so bad and see how it comes out without ironing the tape edges first. One thing about using Superflite with urathane paint and primer, it does cover a lot of sins but it's not the way I like to do it, although very light sanding on the tape edges seems to clean the edges up.

Thanks, glad to know I'm not the only one in the same boat .

Mike Berg

Mike,

This specific thing is addressed in the PolyFiber manual and is pretty simple as I remember but I don't think Superflite works the same way.

I'm pretty sure the glues are not the same since PF is vinyl based.

Almost any PF mistake can be ironed smooth at any stage with an iron at not over 225*, one of the reasons I like it so much.

It's been a long time since I used dope systems but I don't think they can be ironed. As I remember the best system is to soak with glue slightly diluted and then smooth any edges down with a finger until they dry enough to hold.

As I said, it's been a long time.

I shot the bottom with one coat of SF primer this afternoon and it appears I only have a couple of 'ears' sticking up (none were up when I started as far as I know). If I get time tomorrow I'm going to sand out the first coat of primer and tape edges and see how things progress. I talked to Molly at Superflite and she said to stick them down with 'super glue' once everything is dry. Right now things are looking pretty good, but if I have mistakes I'd just as soon have them on the bottom.

Mike Berg

Dear Mike
I teach fabric work for a living but am not a fan of Superflite. Definitely get the pinks laid down. If it is just the actual edge use the point of an iron. If there is a glue void under the tape use a pencil to lift the tape edge and a popsicle stick or such to put some glue under the tape. Have you used Superflite on all of your fabric jobs??

Tony,
This is my third cover job but my first set of wings. I always used Superflite and decided to on this job as I had some material left over from the last. Not necessarily a fan of the product simply because of the heavy use of MEK in the glue which is miserable to breathe so I usually wear a mask when I'm taping. On the other hand, as I previously stated in a post, SF does cover up sins and it's easy to work with. More like auto body with the priming, painting, etc. Also, repairs are easy if needed and although it's heavier than most I do like the poly-urathane paint for the shine and easy cleaning.

At my age (69) I figure this is probably my last recover job, but if I was to do another I would seriously look at the Stewart water based system. I think that's the wave of the future. Almost all new cars use a water based system so I figure it can't be too bad. Actually the wings on my Champ were covered by a previous owner with the old Blue River water based system and still holding up after 15 years although I did scuff and repaint the wings with Superflite when I rebuilt the plane about 10 years ago. On the other hand, the plane is never tied down outside either.

Mike Berg

Mike Not sure that 69 means you are done with fabric. I am 74 and did six different jobs last year including ones in Canada and Hawaii. I am old fashioned at like things that have proven themselves. I am not a "test" pilot but have flown over 100 M&M. When folks ask me "which covering system" I like ones that have been in use many years. I remember that we got the first 747s at Panam and spent some years with engine problems that later versions did not have.