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Acura MDX Headlight Tab Repair with Tab Magic Molding Putty
Many front-end collisions result in broken headlight tabs like this. Today’s headlights often feature LED bulbs, moveable elements, and sensors which greatly increase the complexity and cost of the headlight.
Headlights with broken tabs on top which would be visible to the vehicle owner must be repaired and refinished to restore the original OEM appearance. Some headlight tabs are smooth and relatively easy to refinish. Refinishing is difficult when the tab includes ridges, gussets, and waffles.
To ease the repair and refinish of these complex tabs, use Polyvance’s 6225 Tab Magic Molding Putty. Tab Magic is a non-toxic and highly temperature resistant two-component silicone rubber. The Tab Magic putty is pressed into the details on the cosmetic side of the tab to keep the weld on the backside from blowing through and creating imperfections which would make it difficult to refinish.
We’ll go through each step of the repair process on this 2017 Acura MDX headlight. The list price of this headlight is nearly $1,400.
If you like this video, you may be interested in our PR-03 Headlight Tab Repair Course.
Always wear proper safety gear while working!
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Click here: https://www.youtube.com/watch?v=flNmbXpUqz8
Products Used:
Note: This is a list of the Polyvance products that can be used to make this repair. This list does not include sanders, grinders, or other common tools you will need. If you have any questions, please don't hesitate to call technical support at 800-633-3047.
- 6225 Tab Magic Molding Putty
- 1000 Super Prep Plastic Cleaner (several options available) OR 1001-4 EcoPrep Plastic Cleaner
- Hot Spot Plastic Stapler
- 6125 Tapered Burr
- 6122 Heavy Duty Round Burr
- Nitrogen Plastic Welder (several options available)
- A variety of polypropylene welding rod. We used the round rod and different ribbon widths for this repair.
- Plastic Magic Adhesion Promoter (several options available)
- 3701 Bumper and Cladding Color Coat (several options available)
Video Notes:
- English Closed Captions have been provided for this video. Click on the CC button to turn them on or off.
- The length of this video is in no way representative of the actual time required to perform a complete repair and therefore should not be used for estimating purposes.
Music Credits:
- "Sage" by Slenderbeats
From the YouTube Audio Library
English Transcript:
Many front-end collisions result in broken headlight tabs like this. Today’s headlights often feature LED bulbs, moveable elements, and sensors which greatly increase the complexity and cost of the headlight. For example, the list price of this Acura headlight is nearly fourteen hundred dollars. This instructional video shows how to repair this complex headlight tab using Polyvance’s 6225 Tab Magic Molding Putty.
Headlights with broken tabs on top which would be visible to the vehicle owner must be repaired and refinished to restore the original OEM appearance. Some headlight tabs are smooth, like this one, which is relatively easy to finish. Refinishing is difficult when the tab includes ridges, gussets, and waffles like these tabs.
To ease the repair and refinish of these complex tabs, use Polyvance’s 6225 Tab Magic Molding Putty. The Tab Magic putty is pressed into the details on the cosmetic side of the tab to keep the weld on the backside from blowing through and creating imperfections which would make it difficult to refinish. We’ll go through each step of the repair process on this 2017 Acura MDX headlight. This tab has deep waffles which would be impossible to secure with aluminum tape alone.
The first step of any plastic repair is to clean the plastic. Here we are using Polyvance’s 1000 Super Prep plastic cleaner to remove any mold release agent or oil-based contamination on the surface.
Most headlight tabs fit together tightly because the housings are normally made of polypropylene with a talc filler. As you can see on the ID symbol, this housing says “PP dash TD30”, which means the polypropylene has 30 percent talc filler. This talc filler makes the plastic brittle and causes it to break off cleanly. This means that broken tabs normally fit together very tightly as you see here.
To tack the tab firmly in position, melt a staple into each side of the tab. We’re lucky in this case because the sides of this tab are fairly thick, so we don’t have to worry about the staples melting all the way through. We are using a straight staple on one side and a “V” shaped staple on the other side. No two headlight tabs are the same, so use whichever staple fits the shape of the tab best. We will leave the staples in to further reinforce this repair, so we’ll smooth some melted plastic over the staples using the airless plastic welder. Don’t cut the ends of the staples off until you’ve welded the tab on.
The next step is to mix and apply the Tab Magic molding putty. Scoop out equal portions of both the white and green sides of the Tab Magic and flatten them out on a clean surface. Make two pancakes about the same size and thickness. Put these pancakes together and start kneading them until a uniform green color is achieved with no white streaks. You have to work fairly fast because the silicone putty will start to get hard in about two minutes. To get the putty down into the waffles, nip off a little and push it firmly into the depressions, especially along the crack. Continue to pack the putty into the depressions and pile it on high enough to give it some structure when you peel it back off. Let the putty set up for about twenty minutes before you continue.
When the putty is set up, flip the light over and fixture it to the table. Using the 6125 carbide cutting burr, grind a v-groove about seventy-five percent of the way through the plastic along the crack. This will allow you to do a single-sided weld which will weld all the way through, while the Tab Magic putty will prevent the weld from blowing too far out on the other side. To further strengthen the repair, it is very important to weld across the crack. Here, the distance between the gussets is just right for some ribbon rod, so we’ll also grind a shallower v-groove here with the 6122 cutting burr to prepare for welding across the crack.
To customize the width of the welding rod, we are cutting the R02-05 wide ribbon to just the right width for it to fit between the gussets.
Now that the surfaces and the welding rods are prepared, first weld along the crack with the round polypropylene welding rod. As always when doing a nitrogen plastic weld, make sure to melt both plastics at the same time by focusing the hot nitrogen gas at the point where the rod meets the base material. Melt the base material just in front of the rod, and melt the rod just before it comes down onto the plastic. Apply a light downward pressure onto the rod to fuse the two melted plastics together as you make your pass. Because the v-groove was fairly deep, we will make two passes with the round rod first.
Allow the weld to cool a bit and then reinforce the first weld by welding across the crack. Here we are using our custom-width ribbon rod between the gussets using the same method… melting the bottom surface of the rod and the top surface of the headlight tab and applying a little downward pressure to fuse the plastic together as you make your pass. Use the tip of the airless welder to smooth and sculpt the plastic. On this tab, there is an area between the gusset and edge that is big enough for us to weld some narrow rod across the crack to provide further reinforcement of the tab. Since we are only doing a one-sided weld on this tab, it’s very important to build up as much reinforcing material on the backside as possible. As long as the buildup on the backside does not interfere with any adjoining parts, you can apply more welding rod to strengthen the repair. Look at the level of the tab to make sure it hasn’t drooped; if so, level it by hand and force-cool it with air. Allow the tab to cool completely before you continue.
Sand the backside of the tab with an angle sander and a DA sander. The backside appearance is not as important as the top side, but you want to make sure the surfaces that touch adjoining parts are in the right place.
Flip the light over and fixture it to the table. Cut the putty with a razor knife around the staples, then peel the putty back to see what it looks like from the top side. As you can see, the putty kept most of the welding rod from pushing through, but there are some minor imperfections that need to be taken care of. Because the waffles on this tab are so deep, we will use a self-leveling seam sealer in the pockets to fill and smooth the bottoms. Before we do that, we will cut off and grind the ends of the staples and smooth the imperfections on the top surface of the tab with the airless plastic welder. Sand the top with 80 and 180 grit sandpaper, then scratch up the smooth plastic inside the pockets as much as possible with a red scuff pad to prepare for the seam sealer. Mask off any areas you don’t want to paint. Open up the water drain holes as necessary with a drill or utility knife.
To maximize the adhesion of the seam sealer, apply 1050 Plastic Magic adhesion promoter to the surface and let it flash off for about ten minutes. Apply self-leveling seam sealer inside the pockets with a small artist’s brush. Apply as little as necessary to flow out and cover the imperfections in the bottom of the pockets. Also apply seam sealer into the undamaged pockets so they will look the same as the repaired pockets.
After letting the seam sealer cure, spray a satin black paint like Polyvance’s 3701 Bumper & Cladding Coat to match the color of the headlight housing. As you can see, the finished appearance is very close to the original. And even though we only did a one-sided weld, the strength of the repair is more than sufficient to take this headlight to the next collision.
Polyvance’s 6225 Tab Magic Molding Putty helps you to do quality repairs on headlight tabs which have hard-to-restore features on the cosmetic side by preventing welding rod blow-through. Tab Magic is a two-component silicone putty which is safe and non-toxic, yet flexible and heat-resistant. This is another innovation from Polyvance to help you profit from plastic repair opportunities. For more information, go to www.polyvance.com, or call 800-633-3047.
headlamp repairs