| Author | Message | ||
     Tom R. Hutchison |
After getting glowing recommendations, I have decided to use Poly-Fiber's Superfil filler. I am ready to order some from Aircraft Spruce. My questions is, how much? Poly Fiber sells a 1 quart kit or a 3 gallon kit. Has anyone else used it? How much do you end up using? 1 quart doesn't seem like enough and 3 gallons sounds like a lot. Its a lot cheaper by the gallon. From what I have been able to gather on the process (not much either), you use a long straight edge to find the low spots on the surfaces and fill those. And then sand, sand, sand. Any other suggestions or techniques from anyone? Thanks Tom | ||
| John Harlow |
Tom, I used a 4 lb density filler based on vinyl ester resin and MEKP. It's made for the boat industry. I used over 5 gallons total before I was thru.It's amazing how much of the stuff you need. You need to be cautious of shelf life with any of the fillers. I would estimate you will use over 2 gals on the wings alone. My wing to fuselage fairings are glassed on and so I used a lot of filler here also. Also the fuselage top to bottom aft of the windows has an area on the top half that needs faired in to keep a constant curvature with the bottom half. In addition if you want very close gaps at ailerons, flaps, rudder, elevator, door gaps etc, you will be doing a lot of detail filling. All of my gaps were adjusted to just have paint clearance thru out full travel. Hope this helps John | ||
| Tom R. Hutchison |
John, Thanks for the info. I wonder about keeping your control surface gap so close, "paint clearance throughout full travel". I remember they determined the loss of the Cirrus SR 20 test plane was from control surface binding during wing flex. What is the name of the filler you used? And where did you get it. 4#/gal. is not much more than Superfil and probably a lot cheaper. Tom | ||
| jharlow |
Tom, The product I used is called "POLY FILL". In Florida there are a lot of boat builders and suppliers for them. It costs $17.39/gal and cures the same as the resin we use so you can make lots of progress in a days time. As to the clearance I have been aware of the Cirrus problem and have been keeping an eye on the paint surface and with 30+ hours on the plane I have not noticed any rubbing in the gap areas. John | ||
| John Hobson |
Tom, I have been using Super Fill and so far I have used 19 quarts (almost done). If I had known, I would have bought the 3 gallon kits. The quart kits cost about $11.50 from Sacramento Skyranch (cheapest I could find). It really is amazing how much you can get through even when you don't apply it in excess quantities. Superfill is a very good filler, but if I had known of a light weight vinyl ester base filler, I think I might have used it. One important thing to remember about SuperFill is that it is an Epoxy, which means that you can NOT use vinyl ester on top of it! If you have an area (particularly leading edges) that you build up with a lot of filler it is sometimes a good idea to apply some light weight (3 oz) glass over the top. Where ever you have used SuperFill, you will have to use epoxy resin. | ||
| Gary Markwardt |
Tom: I believe "PolyFill" is the product Frank R. uses at Express for finish filling. You could verify by calling him at the builder building. I recall talking to him about it. He said it was the same material he used to repair boats when he worked in a boatyard. I think it would be best to use a vinyl ester based material for compatibility. Gary | ||
| Gary Markwardt |
Tom: I believe "PolyFill" is the product Frank R. uses at Express for finish filling. You could verify by calling him at the builder building. I recall talking to him about it. He said it was the same material he used to repair boats when he worked in a boatyard. I think it would be best to use a vinyl ester based material for compatibility. Gary | ||
| Bob Gisburne |
Tom: I used a variety of things, but finally finished my airplane using the SuperFil. It works wwell and is substantially lighter than alternatives. It does tend to roll up behind the squegee, so I often used peel ply over it to hold it down and provide a smoother surface. (Credit for peel ply goes to Jerry S.) Buy it by the gallon, you'll use it! Also, keep it refrigerated if you are in a warmer climate. Take it out of the fridge about 4 hours before use. I found it lasted longer... Also, measure accurately using a scale, or else you will end up with leftover Part A or B and wonder why. Get plenty of rest... sanding is never done! Bob Gisburne N4382A | ||
| Tom R. Hutchison |
Thanks everyone for the good advice. I searched the internet for "PolyFill" and found the following web site: http://www.atc-chem.com/compound.html#Fairing Compounds ATC Chemical's Poly-Fill looks like a spray on like "Smooth Prime", not a body filler. They do have a product called "Poly-Fair" that sounds more like what we are looking for. At 5.75#/gal it's a little heaver than Superfil at 3.84#/gal. | ||
| jharlow |
Tom, As to Poly-Fair, I have also used this product but it was only available in 5 gal buckets from the local suppliers and as you stated it weighed 5.75 #/Gal. The gal can that I got the Poly Fill name from has no mfg name listed. The supplier is Joe's Auto Marine Ft Laud, Fl. They have a store in Stuart Fl that is near my home where I have purchased the product and it weighs only 4 #/gal. If I can be of any further service on this product drop me a note. | ||
| Jerry |
Hello out there in "Express Land". It is me (Jerry) again. I don't get into the fray very often but I am looking at all the discussion about "fillers" and would like to add the following comments. I did an experiment with the various Polyesther fillers (ala Body Shops) and found that the "light weight" filler was only about 8% lighter than the "regular weight" filler. However, when I mixed up a batch of Qcell" filler, it was nearly 50% lighter than the "light weight" auto body filler. You have the ingrediants already with your polyesther resin and the "Q" cells (3M micro balloons). Mix up a batch and add the catalyst as you use the material. I used this on my Express and it will work very well for you if you will consider the following: As Bob Gisburne indicated, the use of peel ply over the filler adds several advantages in the final process. First, by putting peel ply over the "wet" filler (any polyesther filler) you are able to work/shape the surface to your satisfaction while the material is still wet. Because the peel ply material is porous, the air bleeds off as you work the filler material with a squeegee, board, or other device to attain the desired shape. Once the filler is "cured", the peel ply is removed and you have a surface that is easily sanded with out loading the sandpaper. Most people do not know that polyesther resin does not cure well in the presence of "air". The curing action is inhibited so that the surface is "tacky" or "sticky" which in turn loads up the sandpaper. Two ways to avoid the problem and save sandpaper and work: Either seal the surface as it cures (in the boat industry, wax is added to the resin "top coat" to seal against the "air") with peel ply or wash the surface with acetone after the curing takes place to remove the uncured resin that remains. Using peel ply allows you to "form" the filler just as you have found you can do with the milled fiber and Qcell fillets. If you aren't doing this, try it, you will like it. If you want to have a stable, finished surface after using fillers, (once the shape is correct) apply one layer of fiberglass overlapping to the unfilled area. Then use the "poly primer" (Feather Fill or others) to finish out your work. The point is, you do not have to buy special fillers. You can make your own. Of course, if your choice is to purchase fillers, pick the "light weight" polyesther as they are fast curing and easy to work. "If you aren't using peel ply on all your layups, you are working too hard and not getting the quality/finished work you deserve". Please see the information on my web page if you have not done so. www.sierratel.com/jerico Any comments or additions to the above will be appreciated. A side note: I quit early on using hot glue to "fixture" ribs, etc., and started using body filler. Fillets can be made at the time of fixturing and fiberglass applied immediately. Very quick and easy to re-fixture if necessary as well as compatible with the building materials used in the airplane construction. Cheers, Jerry Sjostrand | ||
| Bill Copeland |
I knew Jerry would be unable to resist the discussion on fillers. Good advice. As for Polyester filler, we have been using "Rage -Gold" mfg by Evercoat. Fairly light,costs slightly more than Bondo, cures very rapidly and sands easily. Should be available in automotive paint stores. We also have used "glazing putty" from the same source for detail areas, pinholes, etc. Remember - take almost as much off as you put on! | ||
| Tom R. Hutchison (Tomhutch) |
My experience with "body fillers" has been very "interesting". I tried mixing my own with the vinyl ester resin, microballons and a little bit of talc and 1/32" milled fiberglass. My mixture produced "mixed" results (pun intended). The filler would not catalyze consistently. I ended up chipping out most of it. I decided to purchase a commercial filler and mentioned this to Dave Huber at Express. Dave told me about vinyl ester based "fairing putty" a salesman had told him about. I finally tracked it down. Its called Duratec Vinyl Ester Fairing Putty. It is distributed by Hawkeye Industries http://www.duratec1.com. I got ahold of a gallon and tried it. It weighs about 6.4 lbs./gal. I mix about 10g of q-cell/micro-ballons in 150g of material. That thickens it up and brings the density down below 5 lbs./gal. You mix a red cream benzyl peroxide hardener with it at 2-3% by weight. So far its worked wonderfully. Its ready for sanding after only a few hours and doesn't load up the paper. They also manufacture two vinyl ester based primers, one a sanding/fairing primer and the other is a pre-top coat primer in white or gray. I spoke with John Rea at Hawkeye and he recommended a "acrylic modified" poly-urethane top coat. Well, back to sanding, sanding, and sanding Tom |