Thoughts on Installing Steel Flares, Epoxy or Weld? Options

[jim912928]

Hi all...I was chatting with my body shop guy and mentioned to him I may be interested in adding factory style steel flares in the future. We got talking about the advantages/disadvantages of butt welding versus cutting with the crimp and welding it in that way. His suggestion was not to weld at all...epoxy them in. His contention is there is no metal warping and today's epoxies are so strong that in a collision the welds will break before the epoxy seam would.

His thoughts were something in the order of:

1. scribe the outline of the new flare on the existing fender
2. cut along the scribe with one of those cutting/crimp a channel tools
3. epoxy the flares into the crimped channel (lays in flat)
4. finish the seam and paint

He said he's actually seen wrecks where epoxied panels held and welded ones didn't.

Thoughts from the group?

Jim

[redshift]

I can go with that.

I use 4 different epoxies in tool making, epoxies have changed... you can almost hone an edge to cut with them, and the shear strength some of them have is unbelieveable.

There is a bonding tape that is used also, will not let go.


M

[vortrex]

my uncle is a bodyman/fabricator and he was telling me the same thing about epoxies a few years ago when I was thinking about patching some rust areas I had cut out. he said the epoxies are extremely strong.

[bondo]

Hmm think I can dip my 914 in epoxy? (IMG:http://www.914world.com/bbs2/html/emoticons/smile.gif)

[redshift]

Yes you can.

There are places up around the Motor City where they strip your ride down to bare metal, and treat it with a kind of 'electroplated' epoxy goo.

It looks like blocked out primer when it's done, and they say it's good for the rest of YOUR life..



M

[sanman]

I would weld them

[scotty b]

The epoxy works great when used properly. They use a special gun much like a caulk gun that mixes the two parts as it exits the tip. You run into problems keeping the panels aligned tightly while it dries.Panels have to have even pressure all the way down the seam which requires either ALOT of c-clamps or drilling holes and attaching with screws every few inches. Long c-clamps required to do flares get expensive for approximatly 10-15,and drilling holes then requires they be filled after the epoxy has cured. As far as the strength of the epoxy....the rep came to a body shop I worked at,spot welded two panels together, and attached two more with the epoxy.Then put both panels on the frame machine and pulled. Spot welds ripped out.......the epoxy panels tore but not where the epoxy was bonded!! It is STRONG stuff (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif) My opinion is to weld them given the hassle of the epoxy in that situation.

[DuckRyder]

The epoxy will work. If your body man is comfortable with it, by all means consider it.

It is actually called panel adhesive. "Fusor" is a popular brand. Many new cars use it in the roof and other structural panels. Manufacturers have various (and changing) opinions on using it in non original structural areas...

Flares should be no problem. (IMG:http://www.914world.com/bbs2/html/emoticons/idea.gif)

[seanery]

I think bradholio is a proponent of bonding them.

[SirAndy]

QUOTE (jim912928 @ Jan 31 2005, 02:45 PM)

His contention is there is no metal warping and today's epoxies are so strong that in a collision the welds will break before the epoxy seam would.

(IMG:http://www.914world.com/bbs2/html/emoticons/agree.gif)
your body shop guy knows his shit!

he's right ...
(IMG:http://www.914world.com/bbs2/html/emoticons/wink.gif) Andy

[IronHillRestorations]

I guess I'm old school. I'm a fan of butt welding flairs. Any time you've got a lap joint, you have the chance of moisture getting between the two layers (three actually three if you are "gluing" steel-epoxy-steel) and causing corrosion. You'll always have some Porschephile coming up, sticking their hand under the fender and seeing if the flairs were "correctly" installed. Does that mean butt welding is the absolute correct way, I don't know, but I wouldn't do it any other way.

I'm sure the new epoxies are much better than a few years ago though.

All the body men I've talked with want to flange and lap flairs. I've always wondered though how much of that is motivated by the way they've always done it. Most shops don't want to butt weld flairs. Speed is also an issue for body men, and epoxy is fast.

Ultimately it's your decision. Ask 10 guys and you'll probably get 5 who say weld, and 5 who say epoxy is the way to go.

[Bleyseng]

How did Porsche install the flares? I thought they were butt welded...
I have used some expoxies that had a shear strength of 20,000lbs. Amazing stuff and don't get it on your hands! Drys in 5 minutes too. I don't like the idea of lapping the metal as I fear it will rust between the layers. If you get near water it will find its way!

Geoff

[ppickerell]

I have seen an Elise stripped to the frame recently and most of the joints on the car are epoxy. More reliabe than welds.

[scotty b]

Rusting with the epoxy is not an issue if applied correctly. When the epoxy comes out of the tube it is a bead, and if kept even the bead spreads out when the panels are clamped. There is no air pocket so the metel will not sweat as a lap joint would if welded.The trick to the epoxy is getting it placed correctly and keeping it there until it hardens.

[Evill Ed]

One problem I have experienced over the years with expoxy is caled "ghosting". Eventually, the seam of the 2 panels will begin to show throught the paint. This is more noticable with darker colors.

3M and Duramix have had tech bulletins in the past recommending that you use these products where the seams are hidden or covered with trim.

The seams are very strong and do not come apart, structurally I have no issue with these products, but I always worry about the long term cosmetics.

The only epoxy systems I trust and recommend right now are the Lord Fusor line.

Welding eliminates this worry, and butt welds are the way to go.


Ed

[scotty b]

Somthing else that worries me is if the car is in an accident in the future and that panel has to be replaced......... (IMG:http://www.914world.com/bbs2/html/emoticons/flipa.gif) I did a whole rear 1/4 panel on a 914 a few years back with Duramix and that was my first thought,you'll NEVER get those panels apart!!

[Evill Ed]

QUOTE (scotty b @ Jan 31 2005, 05:35 PM)

Somthing else that worries me is if the car is in an accident in the future and that panel has to be replaced......... (IMG:http://www.914world.com/bbs2/html/emoticons/flipa.gif) I did a whole rear 1/4 panel on a 914 a few years back with Duramix and that was my first thought,you'll NEVER get those panels apart!!

Actually, you can get them apart pretty easily. The epoxy has great shear strength. But if you peel the seam, like rolling back the lid on a sardine tin, they peel right apart. An air chisel with a wide, thin blade between the seam will also pop it apart easily. And then there is heat, a torch works like a charm.

Ed

[redshift]

zactly!

I like the idea, and I trust the seam would be mosture free, if you watched your technique.

This would be a joint that I would want very tight, but not very_very_very tight, I think I would take as much time bonding, as welding... and I have 0 useful welding experience.

If you DA'd the seams a lil, and filled with skim coats of epoxy, inside, and out, you could make it nearly undetectable from a weld.... and welds have that way of rusting..


M

[jim912928]

This is a great discussion! My body guy welded my 911 turbo flares on my SC and did a great job. But the more I think about possibly flaring the 914 the more I like his idea of epoxy. This shop is a corvette restoration shop and they work alot more with the chemical stuff versus the welding stuff. So this wouldn't be a new thing for them.

[scotty b]

QUOTE (Evill Ed @ Jan 31 2005, 05:46 PM)

Actually, you can get them apart pretty easily. The epoxy has great shear strength. But if you peel the seam, like rolling back the lid on a sardine tin, they peel right apart. An air chisel with a wide, thin blade between the seam will also pop it apart easily. And then there is heat, a torch works like a charm. Ed

(IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif) Thats nice to know, maybe I will keep the gun after all. I was going to get rid of it because I didn't like the thought of a "permanent" panel. (IMG:http://www.914world.com/bbs2/html/emoticons/aktion035.gif)