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Fender Repair need Help

dougjordan

New member
Just want to smooth up and seal so I can use touch up paint. What should I use for sealing ?
 

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Use some fiberglass resin

I would buy the smallest amount of fiberglass resin and hardener you can find and mix a little and dab it on until you have overfilled the damaged area just a little. But first tape over the none damaged stuff and be real careful with the resign. Degrease and remove all wax buildup from repair section before you make your repair. Use a really small square of 320 wet/dry paper and wet sand the repair until it matches the contour of the fender lip, lightly wet sand repair with 600 wet/dry and then pull the masking tape and clean off the area with Dawn dish washing soap and water and rinse it real good. Re-mask the good part from the repair and hit it with a good quality rattle can sealer primer. The real challenge will be to match the paint with such a small area and it will be the most difficult part of the repair and may take some trial and era to get it close enough to make it disappear. Once you have your paint matched take a small piece of 600 scotch-brite scuff pad and scuff up the primer sealer only, wipe it off real good with a dry clean white rag and touch it up with with your touch up paint using a small flat brush being careful not to leave brush marks. Clean your brush and hit the repaint part with a little clear. I would suggest going to a hobby store to find your paint and clear coat if you don't have a friend in the automotive paint business.

Holt BMW will fix it better than new, he's about the best but he ain't cheap.
 
Use Duraglass. Fancy glass used by high end auto repair places - one BMW auto repair place put me on to it.

Can't buy at AutoZone or the like. Must purchase from auto paint source.
 
Duraglass is good stuff but

I have used it but it is for larger rougher repairs and its nearly impossible to get a paint quality surface with it. Duraglass tends to have small air pockets and dimples. You have to finish the repair with light weight bondo to get a nice smooth paint quality surface. It will work but with more steps and more chance to mess up the good paint. The paint will be the hardest part of the repair.
 
It's such a small area I think you could get away with 5 minute epoxy to fill and sand. The pict looks like there is enough material left for strength. If you buy fiber glass or even bonda your going to have to buy way more than you need. I Think bondo may sell some sort of fiber reinforce bodo..seem to remember something like that being available.
 
J&B Weld is terrific stuff

Epoxy is a good and more economical repair idea as far as the amount you have to buy but you have to understand the pit falls of it as well. Once again you may end up with a not ready for paint surface but also the repair will be a stronger and more durable surface than the surrounding areas so when you sand your repair to shape you may be digging out or damaging the previously undamaged surface also. You will have to sand the repair into the proper contour as well as smooth out lumps and divots. If the surface your trying to match sands down easier or quicker than the repair you will never get proper feathering of the joint between existing and damaged area, in fact you may make the damage and needed repair expand if you aren't careful. Most any local hardware stores or even Wallmart should have a small fiberglass repair kit (resin, hardener and glass) that will work and yes there will be extra. You could always look around and find a piece of broken fiberglass or badly damaged Airhead fender and practice your repair technique. I cut my teeth on fiberglass fender repair with a pair of damaged /5 front fenders that I turned into a very nice set (front & rear) of hand built cafe' fenders that look nearly factory made. If nothing else the practical experience will help you out if you ever tweak a fender again.
 
Use a quality brush for the painting - no matter what method of fiberglass repair. Go cheap on the brush and your efforts will be for naught.
 
Cost must apparently be an issue. That is a question you would have to answer for yourself. Sure, buying too much will be more than you need, but still could be used elsewhere around the home/garage - lots of projects

To me, the bike is worth the effort and expense. I am a lover of JB weld, but it does not harden well, at least in the sense of sanding. It will be soft enough to clog up paper and could make it worse.

Just one of those fiberglass kits from AutoZone or WalMart is good, but ONLY if you just use the resin, and not the glass cloth. Your application precludes the glass cloth. But, the resin will work, but be messy, and hard to "form" as it is pretty liquid at time of working.

I still (from experience) for your application think the duraglass will work best. I admit that you will have to purchase more than you will need, but it has the glass particles embedded in the glass and so you get strength and form-ability when you apply. Someone above was correct, though, that it will not leave a perfectly smooth, paintable surface. It should be finally finished over with Bondo as it can fill in those little imperfections and will sand out super smooth, and then paintable.

I do think, however, that there is a place for the fiberglass resin with the glass cloth - that is where you need to cover over a large hole or form some new shape. It also works very well for leaky gas tanks (both auto and motorcycle) as when surface is properly prepared, and then resined over, and then cloth is put on to reinforce, you can create a pretty strong surface that is almost indestructible.

On my fairing, last winter, I filled in the side "running lights" on my Luftmeister (as I did on my previous one 25 years ago). The holes were nearly 1-1/2" diameter. I used the glass cloth on the inside to cover the hole, then on the outside I kept building up the resin with various applications, and then when just "below the finished surface" I then used Bondo. I did the same for my sidecovers where they had been cracked. Once, done, I really believe that virtually no one could see any variation from the original surface and the surfaces I created with the glass.

For your application, I think it is worth the extra expense to purchase the Duraglass, and the Bondo. May save you $$$ in headaches, too.
 
PS on the above. I think the side running lights that Luftmeister chose looked like crap!! Those lights were the same ones used by truckers made by PM corp. Originally, they looked "pasted" on. That is why I removed them and filled the surface smooth.
 
I think the side running lights that Luftmeister chose looked like crap!!

We used them on Windjammers too, and I agree, they weren't too .... "exciting" as design elements. But due to cost consideration "off the shelf" was the best we could do, and Peterson Manufacturing was the least objectionable. The Windjammer SS, with it's leading edge lights was Vetter's answer, with the side benefit (pun intended) that they provided more square inches of illuminated surface.

As small as your repair is, I think I'd just get my hand on a little piece of fiberglass (mat or cloth) and chop it into some fine material (1//16 -1/8" lengths) and mix it with some epoxy adhesive. Epoxy doesn't much care what you put it on, and it adheres well. Block it out with some 150, touch up the low spots with a little bondo and then take it down to 400 and prime it with rattle-can Krylon. Color match??? good luck.
 
scufs on front end of fender

Hi, read through some of the answers, once you have made the repair you could reverse the fender so the scuff repair is at the bottom rear, may not be as notable ,hope this assists Jimmy
 
once you have made the repair you could reverse the fender so the scuff repair is at the bottom rear, may not be as notable

well, I suppose you could but you would also need to fill in the lower bow mounting bracket holes. The holes on the fender are not symmetrically spaced from the ends - the fender would appear "short" in the back, and "extended" in the front. If you draw a line up the fork stanchion, and then draw another line from the center of the axle to the lower tip of the fender you will see a 90? angle. Do the same with the tip of the fender at the front and you will see what I'm talking about.
 

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my mistake

Hi, my mistake I thought it was a /7 we were talking, about, and I see now it doesn't say so!,,old timers ,lets see the finished job,best of luck Jimmy, p s, just had another look at the photo,it is a/7, going by the wheel, snowflake,
 
Hi, my mistake I thought it was a /7 we were talking, about, and I see now it doesn't say so!,,old timers ,lets see the finished job,best of luck Jimmy, p s, just had another look at the photo,it is a/7, going by the wheel, snowflake,

My /7 looks exactly alike, and the fender on it can be reversed. There is no fender brace running back to the lower fender. Only mount are the 4 bolts up on the stainless fork brace.
 
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