This is new to me but I need to bond some steel panels to some fiberglas body panels. Whats the hot set up here? Will regular body bonding agent work or do I need something special?
It's a myth. The 2 don't actually bond together. You can only incase the steel between 2 layers of glass. It helps to drill 3/4" holes in the steel but eventually it will come apart. The Wizzard
Im doing a new roof skin on my 56 f100 and Im using 3M 08155 Panel adhesive. The link below has the product info on it. Should fit you needs. http://solutions.3m.com/wps/portal/...0000_nid=GSNCT3JT87gsQH8HT14PGTglX46N605CXSbl
Typically steel and fiberglass have differing expansion rates, so any exposure to varying temps will over time cause the delamination of your bonding agent for a separation of the panels. The hot setup is to keep steel with steel and f/g with f/g for a more permanent repair. Mix them together, and it is temporary.
Best i found for adhesion was to mix a bit of 'bondo' into the fiberglass but it's best not to use fiberglass on steel. The fiberglass i'm talking about is the kitty hair type in a can.
My friends teach bonding perhaps you can get a little information from their courses http://www.abaris.com/IndividualCoursePage.asp?CRSID=5
I've always had good results drilling several small holes through the steel, so that the resin can seep through, using a couple of layers of chop mat on the backside of the steel panels and finishing the top of a fiberglass panel off with some Dynaglass. Countersinking some sheetmetal screws or pop rivets into the fiberglass panels is a great help also, it'll keep the fiberglass panels from shifting.
hit the metal with 36 grit paper first.something to bite to.fiberglass resin will work fine,and seal your work.
Use a Urethane Adhesive / Sealant [ not straight urethane sealant it is slightly different ] I've used it to glue a front end to the birdcage on my corvette race-car. and also trailer fenders onto trailers. I have also used it to glue 1/8 diamond plate decking onto a trailer frame , there was no heat warpage [ and it"s stronger than stitch welding because the bonded area is greater ] My prefered brand is "SIMSON" ISR 70-03 by Bostik I wouldn't hessitate to glue a whole Hotrod together with the stuff [ provided the design was correct ]
do a search, this has been covered here many times......and the short answer is... IF you know how= it works very well and will last a long time. this hood scoop is glass, on a steel 4 peice hood[ welded up into one peice clip]....both things said to not be possible ,and to make last.... this 40 Pontiac coupe I built has held up very well and is still being shown on the east coast after more than 16 years since bonding the two together......
at Zipper's we used "bear shit" that was made in house. Sadly I've forgotten what was in it, but id venture to guess it was along the lines of kitty hair bondo, figerglass resin and hardener. Glopped on between the glass and metal, and then encasing the metal as well.
West systems epoxy mixed with I think it is their 404 powder for dissimiar materials. This forms a paste. This seems to hold very well. You can use the WS with a tight weave cloth too. I use this for a bond/sealer but not a high structure area.
Already mentioned, encapsulate the steel into the part with fiberglass and resin. Do a course sanding of everything first. Epoxy resin is better stronger(and more expensive) than "regular" polyester resin.
I have taken four different courses from Abaris, If they cant bond it, it can`t be done. Who is your friend? first name only.
Mike?? is that your name[Sams cousin I presume?], my name is Kenny, Dave Talent's SHOP did the paint work,on The car I did the FABRICATION WELDING AND ALL Initial BODYWORK UP TO FINAL BLOCKING/ PAINTING..... I used Bondo glass [3M] from Wal Mart......
I mounted a metal plate that I had mounted my Accel box to the fiberglass body of my '60 Corvette. I drilled a number of holes in it like previously mentioned and sed 3M 8223. That was 5 years ago and it hasn't fallen down yet. As a side note, every midyear coupe (1963-1967) has a structural steel frame known as the bird cage and fiberglass bonding panels are bonded to this steel fame (this is what the body panels are bonded to) and have held up for almost 50 years. Do a google search and you will get suggestions.
Generally speaking this is a recipe for disaster. It may look good for 2, 3, 4, maybe even 5 years but in the long run it's going to be a mess. As already mentioned the differences in the material characteristics is the problem. Steel and composites have widely differing coefficients of thermal expansion. You also have to think about corrosion. If any moisture gets trapped between the steel and fiberglass it's going to get nasty. There may be some tricks you can pull...like drilling a lots of holes to let the glass flow through the steel or cutting slots in the steel to allow it to expand with the glass and encasing the steel in glass.... but still this is not a good long term plan. If you're ok with this just looking good for a few years and re-doing it later then that is up to you.
I'm Robert, I used to work for Mike until a couple years back. I did get a chance to meet Sam before his passing, and even gave him a couple rides to the hospital, as volunteer in local rescue squad...
Man! I never expected such a response on this subject. I've come to the conclusion this "ain't gonna work". I,ve never owned a car more than a year or so but I don't want to hang the next guy with my substandard work so I've decided to just make full panels out of 18ga. and skip the bonding entirely.
I have seen numerous race boats where steel is glassed into the boat's structure. Not an expert on this, but I have seen cases where the glass failed, but not the bond to the steel. I know some of the older Corvettes had steel somehow bonded into the car's fiberglass. Is something different done in those situations, or do those cases eventually end up a "mess"? There are LOTS of cases where wood structure and fiberglass have been combined in boats and car bodies. Wood and fiberglass are dissimilar materials. And like metal, wood is adversely effected my moisture. Do those applications eventually turn into a mess, even if they are done right? Some car and truck manufacturers are successfully gluing body panels together with some kind of adhesive(urethane I believe) that tolerates vibration, expansion/contraction, moisture, etc. Whatever that material is, maybe it's a possibility?
I've got 37 yrs. on my glass to steel bonded fenders, and people still tell me it's going to come apart someday. Hope I'm alive to see it.
I have done it for years (I'm 62), just body panels, nothing structural. I have never had a problem or even a stress crack. Back in the 70's I put 4 fiberglass fenders on a 56 Bird when no steel ones were available, and 10 years later they were still fine. Just my experience, but what do I know.
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