fixing cracked bumper
#1
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fixing cracked bumper
I finally found a front bumper for my car but it has a small crack on the corner of the turn signal. I'd say it's less than 2 inches long.......how should i fix it? I was thinking of some type of epoxy on the inside of the bumper, then i can fill the outside of crack when the car is painted........What do you guys think?
#2
ive fixed some cracks like that befor.
im sure its not the "best" way to do it, but it has worked fairly well with my experience.
you can get the flexible epoxy from 3m, i thinks its called 4040 or duramix not sure exactly. you can also buy the "bumper repair kit" from advanced auto, its alot cheaper and ive used it with great results
first you line up the bumper on the outside and tape over the crack to where it stays even
then on the backside, make a V shaped trench along the crack
used around 100grit sand paper and scuff up the trench and around it to make sure the epoxy will stick, and clean it
after that mix up the epoxy and fill the trench put plenty on there and build it up and spread the excess onto the part surounding it that you sanded
when that has fully dried, remove the tape on the outside
and repeat the process you did on the inside just only fill the trench with epoxy
after that fully cured, block sand the outside to make sure theres no epoxy higher than the bumper
then you'll need some Ever Coat poly flex. its just a flexible filler that will not crack when the bumper is flexed
take the filler and fill in and smooth out the outside, and block sand that when it is cured and repeat till your satisfied
hopefully that made sense and is helpfull
im sure im not the only one thats tackled this type of problem and hopefully someone with more experience and help
im sure its not the "best" way to do it, but it has worked fairly well with my experience.
you can get the flexible epoxy from 3m, i thinks its called 4040 or duramix not sure exactly. you can also buy the "bumper repair kit" from advanced auto, its alot cheaper and ive used it with great results
first you line up the bumper on the outside and tape over the crack to where it stays even
then on the backside, make a V shaped trench along the crack
used around 100grit sand paper and scuff up the trench and around it to make sure the epoxy will stick, and clean it
after that mix up the epoxy and fill the trench put plenty on there and build it up and spread the excess onto the part surounding it that you sanded
when that has fully dried, remove the tape on the outside
and repeat the process you did on the inside just only fill the trench with epoxy
after that fully cured, block sand the outside to make sure theres no epoxy higher than the bumper
then you'll need some Ever Coat poly flex. its just a flexible filler that will not crack when the bumper is flexed
take the filler and fill in and smooth out the outside, and block sand that when it is cured and repeat till your satisfied
hopefully that made sense and is helpfull
im sure im not the only one thats tackled this type of problem and hopefully someone with more experience and help
#4
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the first thing to do in any type of plastic repair is to identify the plastic, TEO/PP/TPE/ are common plastics used in the making of bumpers and plastic on cars today, now those are offlien thermo set plastics which bascily means you need a adheshion promoter for any type of repair material to stick
so with that being typed out, if your bumper is one of those then ya need a adheshion promoter, this is what i do for fixing plastic and or customizing plastic
any type of crack, i make it a rul of thumb to heat it up just alittle bit, sometimes from a accident the plastic is distorted so i heat it up and re shape, then i take a angle grinder and lightly grind both sides of the damage
then i take my cut of wheel and make the v-groove in both sides of the plastic, then i clean it with a amonia free glass cleaner, there is plastic cleaner you can use but if the shop doesnt use that certain type of product, amonia free glass cleaner works just as good
then i D.A. with 80, then i apply the adheshion promoter, let it dry for 15 mins then you can apply the repair material, now for bigger cracks, and or tabs mimssing, i use a plastic repair backing material, apply the material then you apply the plastic mesh onto the backside of the crack, or i`ll plastic weld a crack shut, then i`ll go and use repair material ontop of the weld
i perfer using fusor products, i think 3m products have gone down in quality the last few yrs and fusor has stepped up to the plate, and its all i use , now if the bumper is polyurathene, that is a plastic that needs no adheshion promoter at all, and it has memory so if it has a dent alittle bit of heat and it can reshape very easily
plastic repair and or customizing just like paint frame and body work cant really be taught online us tech can give advice but if you are unsure you should take it to a pro, becasue trust me when i say i have seen so many hacked up and butchered bumpers in my day, and BONDO DOES NOT STICK TO PLASTIC!!!!
so with that being typed out, if your bumper is one of those then ya need a adheshion promoter, this is what i do for fixing plastic and or customizing plastic
any type of crack, i make it a rul of thumb to heat it up just alittle bit, sometimes from a accident the plastic is distorted so i heat it up and re shape, then i take a angle grinder and lightly grind both sides of the damage
then i take my cut of wheel and make the v-groove in both sides of the plastic, then i clean it with a amonia free glass cleaner, there is plastic cleaner you can use but if the shop doesnt use that certain type of product, amonia free glass cleaner works just as good
then i D.A. with 80, then i apply the adheshion promoter, let it dry for 15 mins then you can apply the repair material, now for bigger cracks, and or tabs mimssing, i use a plastic repair backing material, apply the material then you apply the plastic mesh onto the backside of the crack, or i`ll plastic weld a crack shut, then i`ll go and use repair material ontop of the weld
i perfer using fusor products, i think 3m products have gone down in quality the last few yrs and fusor has stepped up to the plate, and its all i use , now if the bumper is polyurathene, that is a plastic that needs no adheshion promoter at all, and it has memory so if it has a dent alittle bit of heat and it can reshape very easily
plastic repair and or customizing just like paint frame and body work cant really be taught online us tech can give advice but if you are unsure you should take it to a pro, becasue trust me when i say i have seen so many hacked up and butchered bumpers in my day, and BONDO DOES NOT STICK TO PLASTIC!!!!
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#8
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You could use a plastic welder if you have access to one. A local body shop did two cracks on mine for $100 including blending the paint to where you couldn't tell it was ever cracked.
#9
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Im gonna call a few local body shops and see if i can get it welded.......I dont have access to a plastic welder so we'll see.....the crack isnt that bad but i figure since its already off the car i might as well fix it