Switching from urethane to chrome bumper

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Mister 4x4

Too Big to Sneak
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San Angelo, Texas
My Car
1971 Mustang Mach 1
So, the bad news is that my urethane bumper is not accepting primer. I told the body shop to use some flexible primer, and they did, but it's soaking it up and cracking despite their efforts. Not to mention, the passenger side has a permanent convex shape at the edge where it's supposed to match up to the fender. Plus, with the hot Texas sun I don't think it'll stay nice, but rather get some cracking, burn up in the sun, and look like crap over time.

Honestly, I kinda prefer the look of the chrome bumper anyway, so I've decided to order a chrome bumper and spacers, and may attempt to fix the urethane bumper on my own at a later date.

OMS has the bumper filler plates used with the chrome bumpers: http://www.ohiomustang.com/store/order_page.asp?itemid=2087

What I need to know is: do the bumper fillers get painted body color, or stay black?

 
IMG_0826.JPGI'm not 100% sure but they look fine black on mine, I too went to chrome front on my Mach it just makes the front look better IMO (go for the chrome extension on hood/fenders too, its very nice look on any model!)

;)

Pic would help D'oh:whistling:

 
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Do you mean the rubber inserts that go n between the fender and the bumper?

As far as I know they stay black.

My vote goes to painted fender extensions though. The Mach 1 one needs that, otherwise it looks like a mislabeled Sportsroof.

 
The Endura bumper folks have some good advice:

http://transamcountry.com/community/index.php?topic=44258.0

and

http://www.goatsgarage.com/bumplft.html

^

The main ingredient in Endura repair is the filler material. There are three major flexible repair materials on the market that I feel are excellent products: 3M's flexible parts repair material No. 05900, H&H's bond-tech flexible plastic repair compound No. 291100 and Mar-Hyde's flexible bumper and plastic patch No. 3310. For bonding or reattaching torn pieces, 3M's structural adhesive No. 8101 will do the trick. Always follow the manufacturer's instructions exactly.
Primers also have to be made especially for rubber bumpers. Ditzler's elasto-meric primer, part No. DPX-844, is a flexible primer that, when properly reduced, will "give" under temperature changes. A special elasto-meric lacquer thinner, part No. DTX-895, is required for reduction. When using this primer, a final sand with 400- or 500-grit wet-or-dry sandpaper used wet is recommended. This primer has little or no filling properties, so make sure the bumper is as straight and smooth as possible!

A primer I used recently with great success is Ditzler's No. K-200 with the company's flexible catalyst, part No. 248, added. Not only does it maintain a flexible consistency, it also has great filling and shaping qualities. This primer also requires a reducer that is matched to various temperatures and shop conditions.

After the bumper is primed and ready for paint, a flexative must be added to the paint to keep it pliable. Ditzler's flexative additive, part No. DX-369, can be added in with the topcoats of paint. Some of the new urethanes and basecoat/clearcoat systems may require a special flex agent.
In the worst of cases, there are four urethane bumpers available on the forum in the $150-400 range. Give it a shot.

Are your end caps painted yet? If so, fill in the taillight panel holes and have him spray the tu-tone as a Boss 351. It's an idea...

-Kurt

 
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"A la naturale." I love it. ::thumb::

"Do you mean those rubber inserts that go n between the fender and the bumper?" Perfect!. ::thumb::

That tells me they're rubber (maybe I should've read the item description a little closer). ;)

Kniknook: Sweet ride! I'm still getting my end caps and hood molding painted, but I've been warming up to the 'all chrome' look. It reminds me of the '69-'70 Shelby nose treatment... which, oh... I don't know - was only a huge influence on how our cars came out maybe? :D :D

Thanks!

 
The Endura bumper folks have some good advice:

http://transamcountry.com/community/index.php?topic=44258.0

and

http://www.goatsgarage.com/bumplft.html

------

In the worst of cases, there are four urethane bumpers available on the forum in the $150-400 range. Give it a shot.

Are your end caps painted yet? If so, fill in the taillight panel holes and have him spray the tu-tone as a Boss 351. It's an idea...

-Kurt
Thanks, Kurt! Sound advice, and I'll most likely wind up tackling a rehab effort at some point in the future - I'm confident in painting small things and/or components myself, just not so much in tackling a body/paint project as large as my whole car (yet).

I think my bumper is totally repairable, IMHO. I just think getting the right formula for the paint to stick to that vulcanized rubber (let's be honest) might be a bridge too far at this point, and I'm just wanting the car back so I can finish getting it together. Don't get me wrong, I'm happy with what my painter's doing and have every confidence in how my car will turn out (including my choice to go with the chrome front bumper). It might sound a little impatient of me, but when I saw the cracked primer, the first thing I thought was, "OK - obviously, this is going to be a challenge... so rather than have them waste more time on this one piece (when I'll be happy with the chrome bumper anyway), just have them give up on it and concentrate on the rest of the car." I don't feel like I'm settling for a lesser outcome, as much as just making a tactical decision that will help move things along, since everything else is going just fine. I know others with more experience will have different opinions [that I do indeed value], and I respect that because this is my first restoration/custom paint job, after all. I just feel like moving on from the bumper is the best way to go, at this point.

I thought about doing the tail light panel black a la Boss 351 style... but it didn't last. After seeing the Mustang Monthly article with the Boss 351 and 429 Mach 1 (both in Light Pewter), I decided to stick with the honeycomb - and already have the trim panel and bright work ready to go back on. The toughest thing is coming up with a plan to get the cool lenses Obsidian is coming up with integrated with the honeycomb - still scratching my head on that one. ;)

 
Thanks, Steve - that's why I was asking. I've seen a bunch of cars with them, and just wanted to make sure.

 
The bumper to fender fillers in the front do not get painted

 
Honestly, I hadn't given that any thought. I'll probably just stick with chrome, since the light pewter is so neutral and silver-tone. When I saw this picture of Nance's car, the chrome bumper was always in the back of my head as something I'd want to do if the urethane bumper proved to be unusable.

19_22_08_10_12_36_50.jpeg


The odd thing is that I'd always really liked the Cragar S/S's, too... and after seeing all the Torque Thrusts cropping up locally, I'm liking the idea of continuing the 'unique' look [of even having the '71] on through to the Cragar's as well - nobody has those in my area anymore (plus, they're less expensive as well). Nance has an awesome car, and it's been a huge inspiration for me... so it looks like I'm building something of a 'Nance Tribute Car.' ;)

 
I like the appearance of either bumper. A big bonus for the chrome bumper, in my view, is that it's a good bit lighter than the Endura bumper. For my car, which came to me with a decent Endura bumper, I'm considering using the bumper to make a mold, from which I'll make a carbon fiber bumper that will be lighter than either the chrome or the Endura. Of course, thinking about that leads me to consider making a carbon fiber hood, which leads me to consider making carbon fiber fenders...

 
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Knoxferatu-if you are serious about pulling a mold off a urethane bumper, I have a few gallons of epoxy resin and some mat. With a bit of dye we could do a mock carbon fiber pretty easily. Resin is a few years past it's shelf life, but mat lasts a long time and a quick test run with some resin would be easy enough.

I also have some 2 part 4pound density closed cell foam that would make a mold pretty easily

 
I like the appearance of either bumper. A big bonus for the chrome bumper, in my view, is that it's a good bit lighter than the Endura bumper. For my car, which came to me with a decent Endura bumper, I'm considering using the bumper to make a mold, from which I'll make a carbon fiber bumper that will be lighter than either the chrome or the Endura. Of course, thinking about that leads me to consider making a carbon fiber hood, which leads me to consider making carbon fiber fenders...
I like all of your ideas. I am 1000% about improving upon our cars in more unconventional ways like the carbon fiber parts! If you make the bumper, I will buy one, given the price is fair... :cool:

 
So the urethane and chrome bumpers use the same mounting brackets? Or one must buy the repro inner bumper brackets?

s3ehyo.jpg


(Image from OHIO Mustang.com)

 
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