How to: Duplicating a radio bezel.

**Giuliano** · 01-16-2005, 01:15 PM

I cut down the box I was using to fit the depth of the mold rubber, covered it up with a posterboard blank cut to fit, and taped up the edges to keep it together.

The tape is important, as it helps to compress the rubber just enough to make a good seal between the two halves of the mold, but not enough to distort the shape of the mold itself.

I taped around all four sides of the box, including the "top", where the pouring and venting holes are.

I cut openings so that I could access the pouring/venting channels, but still get compression around all sides.

The resin's about $36 for 4 pounds, and I probably won't need more than 1-2 pounds of resin.

And now, we wait... for my resin to arrive, probably by next weekend.

**Grey** · 01-16-2005, 09:55 PM

hate to be the 6 year old school girl at an Nsync concert here, but this is really neat. how much do you estimate the project has cost all the way through the completion of the first bezel duplicate? and how much do you estimate each sequential bezel will cost (not including the mold creation cost)?

**Giuliano** · 01-16-2005, 10:44 PM

Originally Posted by Grey

hate to be the 6 year old school girl at an Nsync concert here, but this is really neat.

Hey, my first fan!

Oh, and I noticed you joined the forums on my birthday, 8/26. Cool.

Originally Posted by Grey

how much do you estimate the project has cost all the way through the completion of the first bezel duplicate? and how much do you estimate each sequential bezel will cost (not including the mold creation cost)?

Well, the mold rubber cost me $86 for a 9-pound bucket, and I pretty much used all of it for this mold pour.

The $86 was a special deal, since it was my first order from Polytek, normally the cost is more, and includes shipping. I got free shipping for being a new customer.

Normally the cost is about $110-120 for a 9-pound bucket, depending on the cost of shipping.

I may have to order some more rubber, as later on I'll need to extend the mold in sections, and I'll need to re-pour some.

The resin that I ordered, Poly 1510, currently costs $36 for a 4-pound bucket, $102 for a 16-pound, and $420 for 80 pounds.

I ordered a 4-pound bucket, which should be enough for a few duplicates to start.

Once I pour the first duplicate, I can weigh it to get a good idea of how much resin I used.

I can't imagine using more than $10-15 worth of resin, especially if I order it in 16-pound buckets.

**Giuliano** · 01-18-2005, 03:33 PM

Originally Posted by Giuliano

The resin that I ordered, Poly 1510, currently costs $36 for a 4-pound bucket, $102 for a 16-pound, and $420 for 80 pounds.

I ordered a 4-pound bucket, which should be enough for a few duplicates to start.

This just in - the 4-pound bucket I ordered cost me $25, not $36.

Why?

Because for every item that you purchase from Polytek, the first one of each that you order comes at a reduced price (free shipping).

I really should have splurged for a 16-pound bucket.. probably would have only cost me $75 (vs $102), and I'm sure I could have used the extra resin.

The stuff has a definite shelf life, but it would have lasted ~6 months or so at the least.

**turbocad6** · 01-18-2005, 06:02 PM

are you going to chop & modify the newly moulded part, & then make a mould of that to produce a final finished product?

**Giuliano** · 01-18-2005, 06:29 PM

Originally Posted by turbocad6

are you going to chop & modify the newly moulded part, & then make a mould of that to produce a final finished product?

Yes, and sort of.

Yes, I'm going to chop and modify the newly molded part.

No, I'm not going to make a new mold of the finished product.

I'm going to extend the original mold to fit the new modified part, by cutting out sections of the original rubber, and re-pouring small sections of rubber into the original mold to fit the new piece.

I'll mock up a drawing of what I mean in a few minutes...

**Giuliano** · 01-18-2005, 06:55 PM

Something like this.

The diagram on the top shows what the current mold looks like in a general sense - thicker mold on the bottom (front of the bezel), thinner on the top (back of the bezel).

The diagram on the bottom shows what the extended mold will look like.

The original mold will be cut out underneath the modified section of the bezel (in green), and new rubber will be poured in place underneath the modified bezel (gray).

After the green section of the rubber cures, any overflow or excess rubber would be trimmed, and then a new back for the mold would be poured on top (red).

So I'll most likely have to re-pour a section of the bottom part of the mold (which is thick), and a new top (which is thin), so I'd have to use some more rubber, but not as much as I would need to pour a completely new mold.