How to reproduce lens.

[John Buchtenkirch]

If you are involved with restorations this is probably worth watching. ~ John Buchtenkirch
https://www.youtube.com/watch?v=QMe9MOBjkmc

[billfunk29]

Thanks John, very interesting process.

[cliffrod]

Seems like a very poor technique to produce a silicone or comparable flexible mold with no durable mother or support, no sprue to charge/fill/vent the cavity of a multi part mold and then simply tell the customer to "be careful" while flexing it open to fill it and then clamping it closed in order to get a good result. Might work if you've got some experience, but if you're new to the process ymmv...

At a glance, their product pricing is not cheap but somewhat comparable to similar two part tin cure silicone products I use at around $100-$150 per 10lbs (about 1 gallon). That means the mold they made, approx 2- 2 1/2 gallons, cost at least $300.00 plus positive casting materials. That's a lot of $$ to gamble on a suggestion to simply "be careful". If you're only selling the product, it is a great way to sell more product.

Molding & Casting isn't rocket science. it is reasonably straightforward to produce great results. imho study the process a little more elsewhere before jumping in if you prefer to not waste your time, your money or worse.

[Chris_Hamilton]

Good post Cliff.

[crystallographic]

Reproducing glass lens parts involves graphite molds and pouring hot glass into them.
Jack's Cadillac build shows him drape molding hot plastic sheet for some of his lenses.
Molding plastic is a process altogether different from each of these, described above.
For nice clean molded lens work I would probably use a process different from the Utoob indicated here.

[norson]

I appreciate John's post and learned from it. The other posts add to the conversation, but I would really like to see examples of these other techniques. I was considering purchasing a car a few weeks ago that would need lenses not available. Not metal shaping, but related.