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Hello Everyone,

I am pleased to announce that I am starting to reproduce molded rubber parts. Currently I am in the pre-production stage of just a few items, but the opportunities are endless.

The below photos are of a pre-production Dimmer Switch Grommet (blue) and a good used grommet (black) that I used as a pattern.

If you have any rubber or plastic parts that you would like to see reproduced, please leave a comment or send me a PM. I will need to have or get a good quality piece to make a mold of. An endless amount of colors and variety of stiffnesses are available. Please note that for prototyping below, I used a slightly "sticky" material that shows dirt easily. Anything I produce for sale will use different, normal-feeling material(s).

The Details
The molding process reproduces a very high amount of detail, to the extent that you can see the slight cracks as were in the original, as well as a couple of stray paintbrush bristles (used for prep work) that got detached and left in the mold. Unfortunately the prototype material I used picks up dirt very easily so the photo of it installed is not great; the stiffness is much too low as well. As can be seen especially in the lower left of the hole, the spacing does not look even; this is because the stiff and worn carpet is actually bending the grommet instead of the grommet holding the carpet stiff. (There is a bit of a clearance issue with the kick panel as well in this particular car.) When relaxed it is the exact shape, as is clear in the other photo. But all of these problems will be fixed in due time.

In other words, production parts will be:
- black (or the correct color)
- the correct stiffness
- without minor defects carried over from the original

As well, I will be making better molds with a different mold-making process to greatly increase the success rate of parts.

The overhead costs for molding a new item are really not terrible, so I plan on making a good variety of stuff that has only normal Packard-level market demand. If you have any ideas for things, just let me know. Or if there's not much demand but you specifically want a few of something, I could do that as well at proportionate cost.

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Spud

What type of rubber.?

For the rear axle grommets. I use flexane 80.
Liquid.

For this type of component, probably 60A durometer urethane.

For the carpet grommets, the question is more for ease of installation than anything. You could do 80A duro but it might be too annoying to install. Of course for a suspension bushing, 80 is much more preferable than 60.

For some things I will probably go ahead and cast on the high end like 90A or even 90D. Example: I often see power antennas for sale without the little boots under them. Could be nice to have more of those. Also the rubber washer under the boot, but that is gonna be 60A or so like the grommets.

Traditionally, O-rings and cushioning washers are 70A duro, but grommets and sealing washers are 55A-60A duro. So that's why I plan to start with some 60A as it's correct (or nearly so) for most rubber parts that one would care to make.

I hate to ask these but haven’t these already been reproduced both by Steele and by Metro or were theirs generic?

A while back I sent you the blueprint for the rear factory A/C fender scoop rubber seal as I have reproduced the scoops themselves. It was a complicated piece that would, unfortunately, require modeling from the print rather than using an original as a pattern.

Metro doesn't offer a whole lot and, without going into specifics, I should be able to beat Steele's prices easily.

Yes, that one you sent me I had quite a time trying to get the blends to work in my modeling software. I still have the model; if I tried again I could probably do it. Another difficulty is the style of drawings they used don't give as much detail as one would hope to have for some features. Hard to explain without posting the dwg.

I know. I had the same issue with the scoop screens and even the scoops themselves which would have taken considerable trigonometry to come up with some otherwise missing dimensions. We ended up just scanning an original screen and 3D scanning an original scoop but the seal is far too complicated to scan with lots of hidden bits. The only real useful detail from the screen’s blueprint was the name of the original manufacturer of the material as I was able to order some from them which is the same as used on the rear parcel shelf for the speaker and/or A/C air intakes, then had the pieces laser cut. Another blueprint I ordered for the oil filter relocation tubes on 1955 and 1956 just showed an end detail for the fitting and nothing else! I ended up finding an originals of these too.