Jump to content
Email-only Log-Ins Coming in December ×

  • entry
    1
  • comments
    2
  • views
    1,902

Making an inspection light lens


EuroDat

996 views

The inspection light is is NLA or very hard to find at the least, so I decided to try and make the lens. I had a light in good condition, but the lens was brittle and badly faded.

Since I had all the equipment for making a set of tail light lenses for my 280Z it was not too much work to try make the inspection light lens.

The Equipment I used:

1. Vacuum chamber and vacuum pump. This is needed to remove air from the silicone resin used for the mould and the clear resin used to make the lens. You can do it without using vacuum to de-gas, but the results are not as good.

2. Pressure chamber and compressor. The pressure chamber is used to pressurize the silicone mould when its curing and to pressurize the resin when you mould the lens.

If you don't do this you run the risk of getting a champagne bubble effect. This effect is caused by small air bubbles captured in the resin during stirring.

The silicone mould suffers a different problem. Uncompressed air bubbles in the mould will compress during the pressurizing phase of the lens making. When the bubbles are compressed the mould is then distorted and you get a strange looking lens. Trust me, I know from experience.:stupid:

3. Scale that can measure 1 gram for measuring resin, dye and hardener ratios. Very important for reproduction later.

Note: If you are using dye, I suggest mixing the dye in the resin before adding dye. Mix enough for your total production and keep it stored. Mix the quantity needed with the hardener. This way you maintain the colour through out the production run.

4. Injection needle or device to evenly inject the resin without trapping bubbles in the mould. This is probably the hardest part of making the lens.

I prefer to inject the resin instead of pouring it into the mould. I have found it easier to prevent bubbles this way. I fit a plastic tube to the seringe (plastic tube used for fish tank pumps) and make sure you use enough tube to hold the resin.

5. Releasing agent. Spray pack. This helps prevent the resin sticking to everything you can think of. Makes cleaning easy.

Pressurize the mould. Once the mould is poured it needs to be pressurized to remove any small bubbles. I use 2Barg for 8 hours and warm the chamber to 60°C. This helps cure the lens and helps give it a shiny finish.

Remove the mould, dismantle it and trim the excess of the lens.

2 Comments


Recommended Comments

How would it look if the lens were made without using a vacuum chamber, would there be a lot of holes in the result?

Link to comment

My experience up till now is without vacuum you get a lot of large bubbles is the mixture. Its very hard keeping it bubble free and still mix it thoroughly.

You can compress the bubbles during the curing period to make them small, but if its exposed to heat the bubbles will expand to the point of cracking the lens or making it all lumpy.

Link to comment

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Blog Statistics

    • Total Blogs
      167
    • Total Entries
      251
  • Blog Comments

    • I'm still waiting on a hoist to free up before I can start bolting the new brake parts on my Z, but I did make the drill jig today.  I started with a 12mm thick Mustang wheel spacer with a pilot.  I then made a drawing to layout the holes needed.  I transfered the drawing onto the spacer and I drilled three new 1/8" holes through the jig (spacer) so I'd have the correct 4x114.3mm holes.  One hole is shared from the original 5 lug rotor.  I then bolted the jig onto the Mustang rotor and simply dr
    • Local radiator repair shops used to be plentiful but getting harder to find.  Some of them just specialize in big truck-heavy equipment radiators.  I will be needing to do the same for my project.  I have heard good reports on gas tank RENU but there are none of those franchises in my area.  Good luck, John-Lugoff, SC
    • Decided to go with the 240sx conversion. Main reason is it’s strictly for the street and the parts were easy to source. What I didn’t realize was the 14” wheels won’t clear the caliper. Now looking for a set of 4 lug 15” rims and tires I can use during the build process. Can anyone recommend a temporary solution as far as make and model preferably a steel wheel that I can use until I’m ready to buy the wheel and tire combination at the end of the project? Thanks again for all the help out there.
    • There are several reasons to use the S197 rear brakes.  The rotors are larger diameter than the SVO rotors and they are vented.  The calipers have larger pistons to give them more power.  The big beef with the Maxima rears is that they don't offer as much stopping power as the stock drums.  The S197 rears allow the addition of an adjustable proportioning valve.  The Maxima rears cannot utilize an adjustable prop since the prop needs to be all the way open to get close to enough rear bias. 
    • Any particular reason to use S197 Mustang 5-lug brakes?  The Fox body SVO Mustangs had rear discs with 4-lug.  It's a popular swap to use SVO or T-bird Turbo Coupe rear brakes to retrofit discs to other Fox body Mustangs.  These parts are still pretty common (probably available as a kit).  Might be worth checking to see if they'll fit.
×
×
  • Create New...

Important Information

By using this site, you agree to our Privacy Policy and Guidelines. We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.