Composite Cracks

[Ed Cesnalis]

I have minor composite work that I would like to have done. Who in California or Northern Nevada can work on my yellow CT?

 

Photo is on the roof where composite transitions to paint I think.

 

[Tom Baker]

CT, can you post a picture that is not so close up to get a better idea of where this is?

[Ed Cesnalis]

Tom,

 

its about 4" left of the 'sky light' and I don't have a better photo. I think it is similar but worse to this one on the edge of my windscreen

 

[FredG]

CT, if you take more photos, it may help to put a familiar object in the picture (such as a coin or a ruler, better yet) so we can apreciate the scale.

[Ed Cesnalis]

Thanks Fred. I was installing tape on the wing root and saw this for the first time. At least I thought to take a photo if not scale it and locate it better.

 

I bet its mostly paint repair as are the other various blemishes. I would like to find a repairman that can repair the paint and composite hopefully within 200 miles.

[Anticept]

CT:

 

This is following the edge of the skylight, and I can see a little of the fiberglass poking through. The skylights sit in a recessed hole, and are epoxied in and a small fiberglass liner layer laid over. It looks like the fiberglass is coming up. It's basic work to fix the layer, any a&p can do it. However, if the window is unseating, that is a lot more involved to fix, but 4 inches is pretty far, i suspect it is just the edge oft he fiberglass coming up.

 

The front left windscreen crack is just a surface crack, and is very common in composite planes. Sand the paint off locally, apply new paint, polish.

[Ed Cesnalis]

Thanks, Acept

[Anticept]

Any others you might want me to look at?

[Ed Cesnalis]

Any others you might want me to look at?

 

Well, if you were in the hangar next door sure, otherwise the others don't concern me much other than at some point I will need a minor repair at various places. The biggest challenge will be an kwik and easy paint match. Years ago I was told my paint was easy to match it was simply 'Volkswagen yellow' however I learned since there are many 'Volkswagen yellows' and I don't know how to easily match.

 

The skylight is a different concern, I wouldn't want it to depart.

[Anticept]

Ask FD for the PPG color code, or have a local paint shop that carries it do a paint match (it will be an automotive shop, there really isn't aviation grade paint, it's all marketing). Clean the plane WELL before you do this, and ask them to match each area if they will do it. If not, ask them to at least check the same area a couple times to make sure it got the color correct. Make sure you are getting acrylic urethane paint (PPG concept is used by FD).

 

Paint is expensive. Get ready for the bill.

[Ed Cesnalis]

I don't think FD has a paint code for the yellow CTs but I will check.

 

How is the sklylight fastened? Assuming its bonded is there a procedure for checking its integrity?

[Anticept]

It's epoxied in, with a single layer of fiberglass 3-4 inches wide laid over the edge. There are no fasteners.

 

Don't work on the window first. Start at the paint cracks and follow any delamination. The window will not be able to pull up the fiberglass without leaving a delam trail. If it traces back to the window, then do your window inspection.

 

To inspect the window, you need to carefully sand down through the paint and bondo layer. Don't go through the fiberglass layer on top of the window! You can see through the fiberglass to the bonding sites.

 

It's easy to tell if it is coming up. Delamination looks cloudy or white. There will be some air bubbles all through the window bonding site, that is normal and unavoidable in manufacturing. You are looking for excessive delamination. If it is coming up, you can use a syringe to shoot epoxy into the air pocket if it is near the edge, as long as it is not sticking up above the recess. If it is sticking up, you will need to ask Dave at flight design if it is acceptable, or if you have to remove the window and redo (be ready to spend. This is a long and delicate job, those windows are almost a thousand dollars if you muck them up).

 

If the window looks fine, then STOP sanding! Just take care of the fiberglass edge. Sand it to a 1 inch taper into the carbon fiber (do not sand the carbon fiber!), making sure you have gotten rid of all the delamination. If the outer edge is less than an inch to the edge of the recess, then there is a couple things you can do. You can either lay over a scarf type repair (1 inch overlap), or carefully remove the section of fiberglass in question, and lay up a new section, with a minor overlap over the other pieces of fiberglass around the windshield. Let sit and cure, apply bondo, sand smooth, paint, polish. If it is more than an inch, or is just a tiny area that is less than an inch, then you can just apply a THIN layer of epoxy over the sanded edges to seal the fibers, then proceed to the bondo, sand, paint, polish.

 

As said, I don't think the window is the problem, I think the fiberglass is coming up.

[Ed Cesnalis]

Thanks

[Anticept]

By the way, don't work on the window first. Start at the paint cracks and follow any delamination. The window will not be able to pull up the fiberglass without leaving a delam trail. If it traces back to the window, then do your window inspection.

 

Edited my previous post to include that tidbit

 

Anyways, if the mechanic doesn't know how to do composites, find one who does. Composites are something that are easy to do, but if not done right, it will not last.

[Jim]

Brian Carpenter at Rainbow Aviation in Corning did some composite work on my plane. Might be worth a call.

[Ed Cesnalis]

Thanks Jim

[Runtoeat]

CT, I had the local speed shop do a computer scan paint match on my CT and my friend's. My white CTSW had a different code than my friend's white CTLS. Both colors matched perfect. The computer had differenct codes for PPG or DuPont. The guy who painted my plane works with DuPont. He had me buy DuPont urethane automotive to insure fuel resistance because the area being painted was around my fuel filler.

[Anticept]

CT, I had the local speed shop do a computer scan paint match on my CT and my friend's. My white CTSW had a different code than my friend's white CTLS. Both colors matched perfect. The computer had differenct codes for PPG or DuPont. The guy who painted my plane works with DuPont. He had me buy DuPont urethane automotive to insure fuel resistance because the area being painted was around my fuel filler.

 

Acrylic urethane, right? This is pretty important because it protects the sensitive epoxy from UV radiation. PPG concept is acrylic urethane.

[Runtoeat]

Anticept, yes, acrylic urethane. Thanks for the input regarding composite repair. This is a subject I don't have much knowledge of but sooner or later will need.

[Rogerck]

I recently had some fiberglass repair and paint work done on my 2006SW at Santa Paula Airport and the results were outstanding. I can not see where the work was done or paint matched.

 

Glass work was done by Aviation F/X http://aviationfx.net/

 

Paint was done by Rays Aviation. I have leftover paint, brand and code if needed.

 

Roger Kuhn

[Anticept]

Rogerck,

 

The hardener/catalyst for two part paints only lasts so long. PPG concept only has a manufacturer recommended shelf life once opened of 2 weeks (but is, unofficially, chemically stable for about two years). The paint portion is on condition.

 

I bring this up because if you are also going to share the hardener/catalyst, make sure you tell the person you are sharing with.

[Runtoeat]

Roger, I'm curious what paint was used for your plane. If possible, would you please give manufacturer (PPG, DuPont, etc.). If there's a brand name please include such as "DuPont Chroma One". if you might also provide the code, it would be interesting to know what yours is for comparison to the two CT's I've gotten codes on. Thanks.

[Rogerck]

Dick,

 

I'll get paint info for you next week when I'm at the hangar.

 

Roger Kuhn

[Rogerck]

The paint used on my CT was Valspar Refinish Polyurethane Topcoat, series 829, Low VOC. A sample was taken to the paint shop to get an exact color match and no color formula is listed on the can.

 

Roger K.

[Runtoeat]

Thanks Roger.