67 and 69 Barracuda back-up light

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Dana67Dart

Dana67Dart

The parts you don't add don't cause you no trouble
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Hi all.

After seeing what @soonercruiser had to go through to get proper backup light bulb holders for his chrome housings I thought I would see what I could come up with.

Screenshot_20240311-210402.png




First take (yes I know the tabs are backwards already fixed)
1710191060477.png


After a couple hours if cad and 3 hours of printing
PXL_20240312_010116380.jpg


Bench test of the plastic prototype
PXL_20240312_022746607.jpg


Not a proper test as I do not have the lense and gasket. So too much heat leakage.

3 minutes I could smell plastic heating

10 minutes browning of the plastic above the bulb

15 minutes I'm either nose blind or the smell has subsided

20 minutes I ended the test

But it did not catch on fire!

The black lines are ink from a pen I was using to test how soft the plastic got.

It got soft but did not deform.

Hottest temp I saw was 350 deg F

PXL_20240312_023516632.jpg


PXL_20240312_025055798.jpg

I'm going to make the small tapered end a bit wider and move the walls of the holder out away from the bulb.

My intention is to print this in metal (AL or stainless)

I'll post more results as I get them.
 
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RAT ROD AL said:
Ya Dana ! With LEDs you could back all the way down Pikes Peak and not have a meltdown
Click to expand...
That would be a scary proposition.

But imagine that race, rather then racing up you race in reverse backing down the road at high speeds!


I thought about LED but since the socket can accept an incondescent bulb it has to handle the heat.
 
Dana67Dart said:
Hi all.

After seeing what @soonercruiser had to go through to get proper backup light bulb holders for his chrome housings I thought I would see what I could come up with.

View attachment 1716220377



First take (yes I know the tabs are backwards already fixed)
View attachment 1716220371

After a couple hours if cad and 3 hours of printing
View attachment 1716220375

Bench test of the plastic prototype
View attachment 1716220374

Not a proper test as I do not have the lense and gasket. So too much heat leakage.

3 minutes I could smell plastic heating

10 minutes browning of the plastic above the bulb

15 minutes I'm either nose blind or the smell has subsided

20 minutes I ended the test

But it did not catch on fire!

The black lines are ink from a pen I was using to test how soft the plastic got.

It got soft but did not deform.

Hottest temp I saw was 350 deg F

View attachment 1716220372

View attachment 1716220376
I'm going to make the small tapered end a bit wider and move the walls of the holder out away from the bulb.

My intention is to print this in metal (AL or stainless)


NOW WHAT I NEED....

  1. I need several dimensions from a bulb housing or a housing I can borrow or buy super cheap. It can be rusty or damaged
  2. A lense, broken, cracked, good but super cheap
  3. Gasket or dimensions of the gasket.
PM me with what you have.


I'll post more results as I get them.
Click to expand...


WOW!
What some folks will do to save a hundred bucks!
:lol:
Gotta hand it to ya! I'd never be able to sit still that long!
 
I love doing this stuff.

It's like a puzzle that I can finish.

I take photos and some dimensions.

And figure out what the original designer back in 1967 was thinking.

Did he use numbers like 1.1 or 1 1/8 most of the time I'm finding that the OE designers would use decimal numbers and keep to the whole decimal. 0.1, 0.2 etc. Some times 0.15 or 0.25

Then the angles, if I have the real thing in front of me I can measure the angle, many times I use an educated guess. I figure the designer wanted to keep the machinist from beating him up so he chose easy angles, 30, 45, 60 etc. maybe 10 or 15 if it was really needed.

Curves, mostly circles with the occasional ellipse.

Sometimes a spline had to be used, due to weird geometry.

It's really rewarding when I draw it up and print it and it comes out good, then a bit of refinement, and I have a finished product.


The latest print. Moved some holes and got the base the correct way around.

Next will be the changes to the cone to help with the closeness to the bulb.

PXL_20240312_053337284.jpg


PXL_20240312_053405831.jpg
 
leds come in all color/heat ranges 3000k should be good for back up lights/// paint the inside with UV cured chrome fingernail polish with an air brush and your good !!! need a ground wire ?
 
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Dana67Dart said:
Hi all.

After seeing what @soonercruiser had to go through to get proper backup light bulb holders for his chrome housings I thought I would see what I could come up with.

View attachment 1716220377



First take (yes I know the tabs are backwards already fixed)
View attachment 1716220371

After a couple hours if cad and 3 hours of printing
View attachment 1716220375

Bench test of the plastic prototype
View attachment 1716220374

Not a proper test as I do not have the lense and gasket. So too much heat leakage.

3 minutes I could smell plastic heating

10 minutes browning of the plastic above the bulb

15 minutes I'm either nose blind or the smell has subsided

20 minutes I ended the test

But it did not catch on fire!

The black lines are ink from a pen I was using to test how soft the plastic got.

It got soft but did not deform.

Hottest temp I saw was 350 deg F

View attachment 1716220372

View attachment 1716220376
I'm going to make the small tapered end a bit wider and move the walls of the holder out away from the bulb.

My intention is to print this in metal (AL or stainless)


NOW WHAT I NEED....

  1. I need several dimensions from a bulb housing or a housing I can borrow or buy super cheap. It can be rusty or damaged
  2. A lense, broken, cracked, good but super cheap
  3. Gasket or dimensions of the gasket.
PM me with what you have.


I'll post more results as I get them.
Click to expand...
That is awesome work Dana67Dart!
Just a thought.

What if you panted the part with high temp Silver paint ?

VHT High Temperature Plastic Paint -- High Heat Coatings
 
Super-Cuda said:
What if you panted the part with high temp Silver paint ?
Click to expand...
I thought about that but the plastic will still get hot. Metal is the only way to have the bulb that close to the sides. when I was testing I placed the plastic inside a chrome cover and the chrome cover got hotter than 120 deg (I could not pick it up with my fingers) just from being near the bulb. Think easy bake oven 60 watts can cook a cake!
jazak5 said:
leds come in all color/heat ranges 3000k should be good for back up lights/// paint the inside with UV cured chrome fingernail polish with an air brush and your good
Click to expand...
jazak5 said:
need a ground wire ?
Click to expand...
I believe LEDs would be acceptable BUT since someone down the road could put an incandescent in it, I would be remiss to make it out of plastic. as for the paint it might move some of the radiant heat BUT my testing was done in open air. The assy is actually closed with the lens and the gasket so all heat loss must go through the housing. Metal is the only way to do it fail safe.

If the housing is metal no ground wire needed ( but it would not be a bad idea)

Plastic it would be needed for sure


Why I will not sell plastic bulb holders

PXL_20240312_155927699.jpg
 
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As for final selling price of metal ones (AL or SS) I have one of each on order. I suspect 2 would be around $100.00 plus shipping.

I have not priced the bulb socket at his time but that will figure into the final price.

I really need to see a real one and the lens and gasket in hand to know if I have the design right. A photo and the chrome housing is all I have to go on right now
 
The bulb can actually extend past the end of the socket an ~1/8-1/4 of an inch (Not measured, eyeballed) with the shape of the lens being concaved/convexed outwards... if you know what I mean...
 
could use the printed model for a sand casting/ un less you are capable of metal 3d printing.
 
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Update...

I have acquired 2 oem samples.

I'll be making adjustments to my design.

I should be getting my REV 1 printed samples next week.
 
I was really close, the photos I was using did not show the compound angle on the back at the bulb holder.


Left is new and improved
Center is OEM
Right is first try, photos only
PXL_20240319_031147624.jpg



PXL_20240319_032558053.jpg

OEM
PXL_20240319_032345407.jpg



3D printed sample
PXL_20240319_032631185.jpg


OEM
PXL_20240319_032439858.jpg



PXL_20240319_033540471.jpg


PXL_20240319_033728040.jpg
 
I think one more round of tweaks and I'll be set.

I have an AL and a SS set of the original ones coming. I'll do some testing on them.
 
If there was only money in it I would

I specialize in the parts the aftermarket doesn't

I have many designs and I strive for OEM look and feel.

I can make most anything out of plastic but have to farm out the metal parts.

The plastic is good for a lot of stuff.

If you have a special request let me know

I also do custom parts on request.
 
Why I will not sell plastic bulb holders

CEC37EEB-BB62-40AE-9F51-ED5B2D9C6AB6.jpeg

Yeah I can see why you wouldn’t use plastic
You’d be getting out of your car in a parking lot, some guy walking by would say “Yo, your Barracuda’s on fire”… “Huh? Oh thanks man”
“No dude, your Barracuda’s ON FIRE!”
 
I received my first samples of 3D metal printed housings. Designed from photos only. Now that I have a real one to look at I have modified the design accordingly.

Stainless on the left

AL on the right

1710880015281.png



My first round of testing is done.
Real chrome bezel, real glass lens, real OEM gasket, so no heat leakage meaning all the heat produced by the bulb has to be radiated away by the bulb holder and Chrome Bezel
PXL_20240319_203810061.jpg




After 20 minutes the AL body never got above 208 deg F (with an indoor ambient of 74 deg) there are no signs of stress to the parts (there was some black goop on the gasket that transferred to the AL housing)

After 5 minutes the SS body was at 209 deg F (with an indoor ambient of 74 deg)
at 10 minutes the housing was at 253 deg
at 15 and 20 minutes it leveled out at 262 deg

At first I was fascinated by the quick temp rise of the SS but then realized it makes sense as the AL can radiate heat away faster than the SS can.

The AL also made the chrome bezel hotter faster. The <120, 120 and >120 are "can I touch the bezel for a sustained time" the average human hand can touch 120 deg F continuously, its uncomfortable but will not burn you for a few minutes. My infrared temp gun (as all infrared temp guns are) is useless on reflective surfaces like the chrome bezel, so I used the 120deg rule to estimate how hot it was getting.

I will be testing the OEM housing next and update the results.
1710884849321.png


* 1.66 oz represents the OEM unit, with 0.34 oz subtracted for the weight of a bulb socket and wiring, but I suspect the steel one on the OEM holder weighs more than the AL aftermarket socket

1.90 oz = OEM holder, bulb socket and wiring
 
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Does anyone have a photo of the rear valance with the backup lights off?

Want to see if there is any chance of interference

And could someone get me the diameter of the hole (green) and the distance from the mounting holes to the bottom of the hole (red)

1710892609541.png
 
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Hey Dana here’s some pics of the backup lights and valance panel
Looks like the hole is 1 5/8”, screw holes are 2 1/8” C to C, and screw holes are 3/8-1/2” from the bottom of the hole.
Maybe somebody replaced my valance panel, or maybe the car was built on a Friday because the left screw hole is slightly lower than the right as you can see in the pics.
The housings you made look deeper than the originals and the inner panel behind the valance may interfere with them. It’s not easy holding a measuring tape and taking a pic, so if any of the measurements look or sound off, let me know and I’ll measure again. The connections point up when installed, as the outer chrome covers are angled on the panel. Please let me know if you have any other questions, and good luck with the lights - They look great!

View attachment 1716224087

76DB645D-64B7-4B2F-978E-28ECF3851D96.jpeg


2C2CD5C2-7AC4-435E-B3BB-F669383CAC10.jpeg
 
Topless69 said:
The housings you made look deeper than the originals and the inner panel behind the valance may interfere with them
Click to expand...
The original rev 1 was much deeper.

The latest revision is very close to the OEM height.

If I sent you some plastic samples would you be willing to test fit them?

You would need to remove the OEM metal bulb housing from the chrome bezel.

I have found that the gasket sometimes sticks to the bulb housing.

PM me if your up for it.
 
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