How To Apply Auto Body Filler (Bondo) Rasp and Shape

Hey, it’s Tony.  Thanks for watching the video.   I did a survey on YouTube a week ago on molding the lip on the trunk or doing a finger mold.  Majority of you wants to blend the mold.  In this video, I will show you how to apply auto body filler (Bondo) rasp and shape for a custom look on a trunk lid.

So today, what I’m going to do real quickly is to mix up some bondo, apply the filler and do a little bit of rasping to get everything straight.

We’re not going to do sanding with a DA sander or block.  We’re just going to lay the filler and do a rough draft shaping with a cheese-grater rasp.

Let’s go ahead and get started.

We’re going to clean our trunk lid with a wax and grease remover lightly. Then, we’re going to mix our bondo and lay it on the trunk lid as thick as shown on the video.  Then, we’re going to rasp it.

We’re going to eliminate the old lip and mold the new one until the trunk lift.  We’re going to custom mold the entire thing.

An ingredient called Benzoyl Peroxide separates with the cream when you let it set for quite a while so make sure that you mix up your filler before you use it.  For every golf ball size of Bondo, mix 6-8 drops of filler.

Also, make sure you don’t have dried bondo on your applicator before you use it otherwise, you’ll have scrape marks when you apply your fresh bondo.  You’ll need to take it out and go over it again.

Make sure to put a piece of cardboard underneath the trunk lid because you don’t want to get it all over other pieces of the trunk.

The bondo hardens up fast so you have to apply it pretty quickly.  Fill all the edges and do an upward stroke, push it up into the ridge to avoid putting too much bondo.

You might have to do 2-3 coats and cover up some areas that you may have missed on your first coat.

Then, rasp it.  Before you start rasping, test a little area first.  If it cakes up and not stringy, then you have to wait for it to set a little bit more.

When you rasp, keep it flat with the body edge and rasp at an angle.  Once you’re done rasping, block it out by crisscrossing it on both ways.

Then, lay another coat of bondo to fix the low spots.  Then, spray polyester putty after we sand it and shape it with 80-grit sandpaper.  Then, finish it off with a guide coat.

You will see the complete steps within the LearnAutoBodyAndPaint VIP course.  This is going to be really cool.

This is so easy to do.  You can do this at home.  You can customize your own body kits and do DIY auto body work in your own garage.  Check out LearnAutoBodyAndPaint and get your Free 85-Page Auto Body Manual.

I hope you enjoyed it.  Please Like, Share and Comment below the video.  Check out the other videos and subscribe to DIY Learn Auto Body And Paint Training Site.

It’s Tony from LearnAutoBodyAndPaint.  Check out Casey, my daughter’s Louisiana Catahoula Leopard dog!

See you soon! Bye!


Other Helpful Links:

How To Block Sand Body Filler in Minutes

Custom Body Work Trunk Lip Fabrication Ideas

Automotive Paint Cost – Medium or High End Clear Coat?

How To Repair Dents With Body Filler (Live Google Hangout)

How To Pinstripe Your Car With Vinyl Striping

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