Technical TECH WEEK! Bumper gaurd tail lights

[slddnmatt]

Alright.. here is my contribution to Tech Week...

The Victim..
1951 Mercury, rear bumper gaurds.. but will work for other makes also.
I started off by picking up some supplies from S & W Plastics out here by me, 951-781-4950 they have a few locations

1. 1 gallon of urethane mold maker and hardner
2. stir sticks and strainers
3. spray can of release agent
4. 1 quart of clear casting resin and hardner
5. 1 small bottle of colored die for the resin, there are a range of colors, in this case i used a deep red
6. set of auger bits, if you need some, HF has cheap set that works
well with an assortment from 1/4"-2"
7. sand paper, ranging from 320 to 800
8. soft buffing wheel and rouge for plastic

[chaddilac]

When I saw your name I expected it to be a merc!!

Nice!!!!

[slddnmatt]

I then fabbed a box up out of metal which will hold the urethane. make sure that the box is leak proof or the urethane will oooz its way through!

I then tacked a tab to the top of the gaurd to suspend the upper part of the gaurd.

Depending on your design this will vary but in this case the lenses were stopping about 1/2 way down on the gaurd so i had to trim out the metal mold to accept the gaurd.

I then mixed up a little bit of filler to seal the gaurd to the mold..

I sprayed the bumper gaurd down with the release agent and then positioned the gaurd in the mold and smeared the filler around the bottom to seal it off.

I then poured the urethane to the desired height and let it sit overnight. Like anything with hardners temperature plays a part on the drying time.

[slddnmatt]

Once it was dry i did a little wiggleing and the gaurd pops out. now inspect your mold for any blemishes that need to be addressed. Once your happy you can start mixing your resin.

Since i wanted them to match in color, i added the die to the full quart of translucent resin so i knew they would be the same color, sense i wasn't making both lenses at the same time, then poured it back in its container for later use.

Once your resin and hardner is mixed throughly, spray the urethane mold with the release agent and then pour the resin through a STRAINER into the mold, this is very important to get the air bubbles out of the resin. and let sit overnight.

[shmoozo]

I am liking where this is going.

[HELLVIS]

more

[slddnmatt]

Once the tail light is dry, pop it out with out dropping it! and set it aside in a safe place. now you want to mark out your cut line on your gaurd, making sure its not larger than your tail light you just made and cut it out.

Depending on your shape this is the fun part of getting the lense to match the gaurd nice and perfect.

I wanted the lense to mount from the outside and have a nice smooth transition to the gaurd. so i grabbed my dremel and the cutting tool which is a 1/8" straight router bit to make a nice clean edge. I stole a pic from the internet on the bit... A little fine tuning with a razor blade and a light file to transition the gaurd to lense and check your fit.

The fitment is kinda nerve racking, you have to have a steady hand and if you take to much off, you will usually have to add metal back to the gaurd or pour yourself up another lense

[chopnweld]

Dude, you continue to amaze me. You're a friggin surgeon!

[slddnmatt]

I then marked out the center of the "bullet" on the front of the lense and then found the center on the rear of the lense with a set of cross hairs connecting the two front to back. so if the lens has a slight angle up, down, left, right, you need to adjust the mold to drill down to the center of the bullet that you cannot see. The front being hidden in the mold, so make sure your cross hair angles are right on the money.

next measure your overall thickness of the lense and have that near you because this next part is a pain in the rear..

I then put the lense back into its mold to hold it, then i clamped the entire unit into the drill press making sure that the bit and the crosshairs were inline with each other.

I set the drill press on a very low speed not knowing what the auger bits might do to the resin.

The auger bits cut the resin like butter..

I then went in 1/8" increments from 2" for this application down to 3/4" i think it was, stopping to clean out the shavings to make sure on depth. be precise, because once you move on to the next size thats t there is no going back!

[dt50chev]

Looks great. Can't wait to see the final product.

[slddnmatt]

Once you you add all the 1/8" steps up and you keep telling yourself that your going to drill through and you decide to stop... a little clean up with the razor blade and some trans fluid to oil up the inside of the lens and you end up with this.

I then drilled two mounting holes and tapped them with a 10-24 bit. added some screws and cut the heads off to make them studs.

I then made the lense mount on the inside of the bumper guard, making it the way you see to allow the studs to slide down in because of the lip on the lense.

[slddnmatt]

I then grabbed my lens and sat down with some 320g sandpaper and started smoothing the raw lens out. once i was happy with the 320 i moved up to 400g wet or dry and then i went to 600g. i think i stopped at 600g.

Then i went over to the polisher and started polishing with light pressure so you do not heat up and gouge the platic.

Next was to fab up the bulb holder, i just used some universal metal bulb holders from Kragen that i could modify if need be. i welded a 2" washer and a backing plate on the bulb holders and when mounted, it gets sandwhiched between the lens and the gaurd. you could also put a set screw to hold it together for ease of instillation.

[Anderson]

Incredible....can't wait to see the finished product!

[Drewfus]

I' can't begin to explain how timely this Tech is....the merc is in need of something just like this..

[skoh73]

WOW!!! That is way too cool- great work!

[slddnmatt]

And there you have it, all mounted and purty. It's as easy as that!! I hope you all find it helpful and feel free to PM if you have any questions. Sorry i didn't have more pics, I kinda forget to take pics when im in the middle of doing stuff.

hope you enjoy!!

thanks!!
matt

[slddnmatt]

Greg (51mercules) probably has more pics of them on his car, i couldn't find any in my cashe, and i forgot to take some out at the GNRS.

[The37Kid]

WOW! Nice work, thanks for posting the details.

[Retro Jim]

What a hell of a great idea ! That looks awesome . What a beautiful touch to make your kustom to stand out and are going to be great brake lights ! I love this one and opens up the door to so many different ways of making something special that is very functional too .
Great Tech !

Retro Jim

[Bigbillyrocka]

Ohhh man! I GOTTA do this to my ol gal...great thread!