Image Unavailable, Please Login Science at work while I sleep. This yucky foam was earlier this evening...changed the water out and stuck the bumper end back in the bucket to start the electrolysis process again. This may be a several day process.
I changed the water this morning not foamy. I rotated the bumper to expose the opposite side to the scrap metal anode (+) and the hydrogen release was swirling the water again. The metal is now black (magnetite Fe3O4?)......looks like the crater-pocked moon but looking better! It's working - I'll check on it mid-day and probably wire brush the metal tonight.
From a sports car perspective those pictures are horrifying. That's a huge chunk of metal at the ends of the car. Polar moments and all of that. I mean, I knew it was in there in some fashion but to see it...ug. I don't like the idea of fragile, hollow, useless fiberglass bumpers, but I also don't like 100 lbs of solid steel at the end-most points of the car.
Cleaned and brushed up on the bumper before throwing back into some clean water/washing soda for overnight electrolysis. Looking better! Not sure how much better it will get by tomorrow - the rust looks all gone with 24 hours of electrolysis! Image Unavailable, Please Login Image Unavailable, Please Login put the bumper in the bench vise and hammered out the bent metal - pretty straight now Image Unavailable, Please Login probably throw some epoxy primer on tomorrow night to seal the metal.
Wow! It is remarkable how thick the rubber is in addition to the steel. I had never heard of using electrolysis to remove rust. What electrolyte do you need to use? What is the (presumably) cathode? For the record, the front bumper weighs 40.3 lbs (18.3 kg) and the rear weighs 39.2 lbs (17.8 kg). I too have reconciled myself to the weigh penalty given their better safety performance.
This might be an ideal application for "Shoe Goo" for gluing back the rubber to the metal. I am sure there is a generic name for the Shoe Goo formulation but I don't know it. I do know that Shoe Goo is a great adhesive.
Electrolysis is your friend in the restoration arena for gentile rust removal. Hundreds of youtube videos on the process. I use my battery charger for the process. I just remember everyone moves to the "positive".....so the positive lead goes to the sacrificial scrap metal that the rust "runs" to and clings to. Negative lead goes to the piece you are trying to remove rust. Water is the conduit between the metals and adding washing powder and/or plain salt as the electrolyte raises the conductivity to speed the process. My photos show the connections. The only trick to use the (HF) charger is you need to touch the leads with a battery to trick the charger to turn on (extra jumper cables and my car is right there!). The water starts swirling from the hydrogen releasing (so good ventilation) and can turn nasty real quick! DON'T EVER TRY WITH CHROME OR STAINLESS STEEL UNLESS YOU UNDERSTAND THE PROCESS- THAT COULD LEAD TO DANGEROUS CHEMICALS BEING FORMED - ERIN BROCKOVICH STYLE. I like this video I still may go with a Euro conversion but for now, trying to save the bumper for future owners FWIW. This could still fail if I do not find the right products to pull the rubber back together - you would think in 2020, we would have a solution for a proper adhesive.
Yes - my research keeps pointing to this adhesive as one of the choices. JohnK sent me a good glue possibility the other day but I kept researching. Today I should receive this glue - IC-2000 Rubber-Toughened 1oz CA Adhesive Glue by Bob Smith Ind Glue I think the "super glues" will attach the skin pieces together and a "shoe" glue or a laundry bumper glue could be the choice to attach rubber and metal together.
What you've ordered is considerably different than Shoe Goo, but I no glue expert so am not advocating one over the other. The benefit of Shoe Goo is that it is has a very thick consistency so has substantial gap-filling capability. It squeezes out of the tube like silicone sealant.
Yes, I know - I'm only thinking where there is no gap at the surface level to use the super glue (used for tire repair) and shoe glue where gaps are. I am going to test both and what a solution might be.
Sorry but there is no saving this poor thing. Even the best repair will cost time and $ and you will never completely stop the rust. Had a very similar issue on my 87 Maserati Biturbo, I replaced all the bumpers after trying to salvage them. Thankfully my GT4 has new Euro bumpers. Good luck.
I think your bumper is way too far gone for repair :-/ but fun to watch all the same. Our 308s are low and easily bumped by SUVs with poor line of sight. A trailer hitch is the common culprit. The rubber can be bonded and filled with a sandable flexible bumper filler. I can look up the exact 3M/Marson product I have used if needed. A SEM brand flexible primer/filler and SEM bumper coat will work wonders for finishing. It’s not an easy process. The rubber sands at a different rate than the filler. This makes getting the surface perfect a bit of a task. A skim coat of filler and pneumatic straight line file make all the difference. I have repaired 308 bumpers to perfection using the above materials/method. Currently have 2 uncoated spares sitting around if you want pictures.
3m black windshield Urethane sealer would be a good choice to attach rubber to rubber and to the framework. I would use the sem products That I -Velocita mentioned above for finish coat. We’re rooting for you!
Let's see where I get with $50-80 in materials - I am in the process of reattaching the rubber pieces. The Bob Smith rubber super glue is working great to glue the edges back together. After looking and getting several recommendations at rubber adhesives, I chose Liquid Nails Fuze-It for the rubber to metal adhesive - working good but setup/clamp time is very long and I am using every clamp I own! I got some SEM Bumper Bite filler coming tomorrow and will order some SEM bumper coat and primer like you mentioned. After brushing on SPI black epoxy primer - ain't no rust coming back in my lifetime. Image Unavailable, Please Login I'll add more pictures once the rubber pieces are back on and prepping for sanding and painting. Thanks for the info/advice, James! I would love to see your pictures for this post and 3M products that worked well for you. Pneumatic straight line file? Now I need to find a great price on one! Still may fail in this project - but so far so good - may help the Fchat guy in the future 10 years from now, to decide to restore or replace.
Here are the products I have used for repair. Also see a pic of two bumpers I have repaired prior to final coating. Both bumpers had a centrally located 4”-8” tear in the rubber from trailer hitch impacts. Sorry, I didn’t take any before photos. I’m not sure if the 3M/Marson product is still available. 3M has other epoxy based flexible and sandable adhesive/fillers though. If you are new to bodywork this type of rubber repair can be a challenge. Good luck! Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
thank you, James, for the photos! You are confirming to me the products to use. I'll have photos to show my progress this week or next.
great effort so far, most of us would never of believed this could be saved, BUT look how its coming along, great effort, its not over till the fat lady sings as they say over here
It's been a while, but I believe I have reached the end of this little bumper recovery project. Over the last couple of months, I have stripped about 95% of the front 1/3 of the car .....but I could not stop there and now have about 99% of the interior stripped away. So as I traveled down the rabbit hole of finding rust this summer, I would work on the bumper in between....glueing, sanding, and applying filler. I felt like Jed Clampit whittling a stick....taking my time and contemplating my "quarantined" life as I sanded. Image Unavailable, Please Login Because I am on the fence of going "Euro", I had the boys at work slice up some 1/4" hardboard on the CNC machine from my CAD model I built from some internet photos and basic dims.....see if I can create a fiberglass mold to produce a bumper.....repair the original bumper and put away. Image Unavailable, Please Login I used Liquid Nail(Hybrid) to glue the big pieces back together around the inner metal frame. I used Bob's Rubber Superglue on the skin edges, 2-part Bondo Bumper and Flexible Part Repair adhesive on the larger nicks, and SEM Bumper Bite & SEM flexible primer on the surface finishing. Image Unavailable, Please Login Image Unavailable, Please Login Here's about where (in the project) I'm thinking - Do I have a job tomorrow? Do I have to wear a mask?.....sand some more and think gratitude - to be a blessed guy. Image Unavailable, Please Login SEM bumper coater in a spray can. UPOL glazing to hit the nicks and pinholes. Image Unavailable, Please Login Image Unavailable, Please Login SEM bumper coater info says 2 days to harden. Want to see if the sheen will reduce slightly after drying over time. Now the lenses/housing look worn! But otherwise..... Image Unavailable, Please Login pretty damn good-looking.
I am stunned it came out looking that good. Obviously a lot of time, patience, and care went into it. Bravo! Nicely done!
