- Can bondo be applied on plastic bumper covers?
This is a question I was asked an in this video,
I'm gonna answer it.
(car engine revs)
(thumping music)
Hey YouTube, Donnie Smith here,
and welcome to another Q and A video.
These are the videos where I answer some of the questions
you have on my YouTube channel
and I make a quick video to help answer the question.
So I was asked, says thanks for the video.
Has three questions, says number one,
what's the purpose of putty after putting the bondo?
Number two, should I use different bondo for metal
quarter panel and for bumpers?
And three, what about fillers?
Are there different ones for metal and for bumpers?
And I really appreciate you for askin' this question.
It's a great question.
It's somethin' that does need to be addressed
but I never have so I appreciate you for bringing
this to my attention.
So let's talk about, firt one's,
purpose of putting putty over bondo.
Do you have to?
No, I mean there's a lot of times you can finish
your filler out with a body filler and not even use putty.
In fact, some shops don't like to use putty
because it costs more than body filler.
So that's gonna be kind of a preference.
Does it make it easier?
Yes, you know, because putty, it's thinner.
You know, they glaze putty's thinner than the body filler.
And you can just use it as a last coat,
just a skim coat over everything
and you can go past your feather edges,
which helps level all that out.
Put you a real thin coat on, block it out
and it's really gonna reduce the amount of priming
and blocking you have to do.
I'm a fan of glazed putty, but do you have to use it?
You do not.
Especially with some of the premium body fillers they have,
like the new 3M stuff,
some of the Evercoat, you know,
some of the good quality body fillers they have.
I mean, they really don't pinhole or anything
like they used to so really, it's gettin' a lot easier
to finish em' out with body filler.
So to answer that question, you do not have to use
glazed putty over body filler.
It's just there, it's somethin' that makes it easier.
You know, reduces the amount of priming and blocking
you're gonna have to do.
Okay, number two, should I use different bondo
for metal quarter panel and for bumpers?
And that kind of fills in, blends in with the next one.
What about fillers?
Are there different fillers for metal
and for plastic bumper covers?
And no, you do not want to use bondo
on plastic bumper covers.
It's not designed for that
and if you go to the technical data sheet,
it's gonna tell you that body filler's designed
for steel, galvanized and other zinc coated steel,
SMC, which is sheet molded compound,
fiberglass and aluminum.
Now you note on there,
it does not say anything about plastic.
So, it is not designed for that.
You know, it just won't hold up,
it don't have the flexibility or anything like that.
Now, what you can use,
like if you got a damage, and you're repairing it,
is you can use an adhesive.
I know 3M makes em, that's the ones I'm familiar with.
There's other brands out there.
But it's a two part adhesive.
And the adhesive 3M has, you know,
they come in a tube, a cartridge
and you squeeze it out and you put it
over the repair area and you can block that out
a lot like body filler.
It doesn't sand quite as good as body filler
but you know, it works real well, it's flexible
and it's not gonna pop off or anything like that.
Now they do also make a flexible parts glaze putty.
And that's similar to like a regular glaze putty
but it has more flexibility in it
and it sticks to the plastic better
so that is an option that you have to use as well.
And I would just use that for pinholes,
or minor imperfections.
I wouldn't try to fill in a real low area with that putty,
I'd use the adhesives.
Most of your bumper covers,
the flexible bumper covers
and they're thermoplastic,
not thermoset but thermoplastic type of plastic
and what that means, it's a type of plastic
that you can reheat and reshape.
So if you got a big low in it, you can heat that up,
push it out and allow it to cool and then
it will change it's shape.
So if it's got a real big low,
I'd try to shape it some first.
But then, if it's anything over just a small scratch
or pinholes or somethin' real small,
I'd probably sand it down and go ahead and put
some of that adhesive on there.
You know, just like I would body filler.
If you want to do the last coat with that glaze putty,
that flexible parts glaze putty, you could do that.
Now if you've just got a little nick or scratch
you've got to get out of the plastic,
you know, probably the glaze putty's gonna be fine.
Flexible parts glaze putty.
Now one thing that you do need to keep in mind with plastic,
and this is the biggest problem
you know, that people have with plastic, is adhesion.
It is very necessary, especially with bumper covers,
because they're the type of plastic that has
oil in it and things don't stick to it well.
So you're gonna have to use a plastic adhesion promoter.
Now this is before you put the adhesive or putty
or anything, as long as that's bare plastic,
you really need to put that adhesion promoter.
And that goes for every step,
until the bare plastic is covered.
So let's say you repair it, you put some adhesive on there.
You sand it out, there's still some plastic, bare plastic.
Well before you prime it, you want to come back
and put another coat of that on.
If you don't put that adhesion promoter on there,
it's probably not gonna last,
it's probably gonna peel off.
Well I hope that helps answer your question.
If not, you know, leave me another comment below
and I'll try to answer it better.
Also, if someone else out there,
you know there's a lot of YouTubers out there
that have a lot of knowledge and wisdom,
you know, if you wanna comment on this,
by all means be sure and do that.
If you like this video, be sure and give us a thumbs up,
give us a like and subscribe to this channel
if you haven't.
You know, share this video with your friends
and remember, if something's worth doing,
do your best and have a blast doin' it.
Thanks for watchin', take care
and gonna see you in the next video.