I put some ABS cement on the grille on saturday, and two days later I'm adjusting my plan.

Specifically, I spackled over the places where the inter-bar bridges were, those seem ok; but I also filled the round divot on the face of the bowtie area, which can still be dented with a fingernail. I'm pretty sure none of it bonded particularly well, so I might end up taking it all off.

I am now de-chroming 3 of my 4 pieces of removed bar, which I'm going to dissolve in acetone in an attempt to make my own cement.

(The 4th piece is needed for the secret...)

 

Just a quick note to say yes, I'm still working on this.

Plasti-Dip, after a few tests, has become a non-option: its ABS to ABS bonds are considerably weaker than bonds to itself or ABS to itself. Wierd.

So on a lark I picked up a tube of Loctite Plastic Bonder, because out of all Loctite products, this one specifically mentions ABS in its description. Testing so far has resulted in much stronger bonds than Plasti-Dip, but I think sanding it will be tricky.

More to come...

 

Quick recap since August:

After I put the ABS cement on, I've taken it all off. It didn't bond well, I scraped some of it off with a fingernail. It also ended up full of tiny bubbles, and never hardened as much as I expected.

I tested a product called Plast-Aid, which would have worked well if it actually created a strong bond from ABS to ABS.

I did some more testing with Loctite Plastic Bonder, which specifically mentions ABS in its product description. It made an ABS to ABS bond that was about 5x stronger than Plast-Aid, even on non-roughened surfaces.

Now, on to the good stuff...

Tuesday I positioned my bowtie top/bottom edge pieces with a spot of Plastic Bonder on each. This was tricky, especially the bottom piece which had to float away from the grille to be in the correct position.

Yesterday I filled in the missing bowties edges. This takes day-to-day time because the Bonder takes 24 hours to fully cure.

Today I did some rough cleanup. The Bonder is somewhat tough to file (I'm using a set of detail files), but it feathers excellently, and dosn't seem to shink at all. Here they are as of a few minutes ago:

Top:


Bottom:


I also filled the divot in the face of the bowtie, because getting the ABS cement out of it left the surface really ugly. There are some low spots in the Bonder, so I'll have to put some more on, smooth out again, then do the final contouring. I'll probably also be spending a good amount of time with sandable primer to get everything really smooth.

 

kind of lost with all the steps you have taken to re-stiffen the plastic from all the sanding..so what did u end up doing to make it stronger again?

 

Stiffening isn't really an issue, at least not that I can tell yet. I'm using Loctite Plastic Bonder for filling and smoothing.

Make sure to get the one with the lawn chair on the blister packaging that says 3450 PSI. Get more than you need: the 3 tubes I've opened so far haven't had each side equally filled. I have 2 more, and I might need another 3 after that.

When I do the major fills, I hope I can do it with the accessory hardware in place (at least the middle vertical bar) so I don't end up with the entire thing flexed wierd. I'll do the final paint prep smoothing with sandable primer.

When I'm done, I think I'm going to post a "what I learned" summary at the end.

 

Real progress today!

Before I get to that, let me explain that I've got the top and bottom edges on the bowtie and contoured. I'd post pictures, but because the filler material is transparent yellow, it's difficult to see the surface, even in person. I'll take lots of pictures when I get some primer on.

Speaking of filler, this is what I'm using:



Make sure to get the one that says "PLASTIC BONDER" (not just "PLASTIC"), with the lawn chair and the 3450psi strength rating.

On to the main event...

Today I filled one of the lower bar gaps, so here's how I did it. Materials:

• Plastic Bonder
• Tape (masking/painter's)
• Aluminum foil
• Applicator (I used an old ATM card)

The foil is what the filler will be molded against. It is moderately easy to peel foil away from the Plastic Bonder. Cut a piece of foil about 1 3/4" high (important) and at least 2 inches long (not as important). Even heavy duty foil will be flimsier than you want, so put 2 or 3 layers of tape on the dull side for rigidity. Make the shiny side do the work, it's easier to peel away later.

The height of the piece is important: this should be a little less than the distance between the center and bottom bars. Less, because you don't want the contour from where the adjacent bars meet the side interfering with getting a straight edge across the gap.

If you cut the other bars out the way I did, the openings will be smaller, leaving some surface around them to attach the mold backing. For the lower gaps, I have to span 1 7/16" across the deep edge.

Crease the tape-backed foil about 3/8" from one side, to 90 degrees: this will form the missing edge.

From the front, align the crease to the empty span; there should be about 1/8" overlap with the grille above and below. Tape the edge of the foil opposite the crease to the grille. If the gap opening is smooth, the foil should follow the contour down to the edge. Cut small strips of tape (1/4" x 3/4") to adhere the foil smartly at the edge, from the top and bottom surface of the adjacent bars.

Flip it over. Cut slits in the extended end of foil about 1/8" from the top and bottom. Pull these tiny tabs over to the back and tape them down. The middle section should still be perpendicular.

Here's what you should have, front:



and back:



For an applicator, I trimmed down an old ATM card top and bottom, and cut off another 1/4" wide strip to use as a detail applicator.

Time to get messy. Mix up a little more than half of a tube of Plastic Bonder. Load up the edge of the card with it like putty and spread it in the gap, moving horizontally so the existing material guides your depth. you should end up with something like this:



Afterward, I cleaned up the messy excess with the little card strip. My foil edge was bowing a bit, so I gently put a loop of tape around the side of the grille:



The loop is not taut, it's just enough to keep the edge of the foil straight.

Tomorrow we'll see how it came out.

 

I come in here and look every once in a while, not sure what exactly your trying to accomplish with all this. Are you just trying to strip it and paint it? what color?

ive painted over chrome dozens of times on grilles by using self etching primer and the right prep.

Now I just use plastidip its the easiest thing to use. We did my buddys grille the other day with clear (not gloss) and it took chrome to a frosted brushed aluminum look.

 

I'm trying to accomplish this



but in black granite metallic.

I'm a perfectionist and want it to last a long time.

I've used Plastidip before, I have it on my side markers.

 

Here's what the lower fills look like (I did the other one after my post the other day):







They came out pretty good. There were some bubbles near the surface that I dug out with my Dremel. This step was just to get some material in place, I'll skim over it with more Loctite and work down to the finished surface.

Need to get some more, I only have 1 tube left.

The divot in the bowtie is filled because the surface wound up pretty ugly after I got all the ABS cement out of it.

 

get to the mesh part! lol