Something for the peeps with metal allergies

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LIBrassCo
Posts: 585
Joined: Feb 24, 2019

by LIBrassCo »

Something kinda cool I'm prototyping, resin topped blanks. Doing a few just for some rigorous testing. Here's photos of the first one. Thus far I'm quite enjoying it, nice dark sound.
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harrisonreed
Posts: 6479
Joined: Aug 17, 2018

by harrisonreed »

It looks cool!
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Posaunus
Posts: 5018
Joined: Mar 23, 2018

by Posaunus »

Jeff,

What material did you machine for the cup top?
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LIBrassCo
Posts: 585
Joined: Feb 24, 2019

by LIBrassCo »

[quote="Posaunus"]Jeff,

What material did you machine for the cup top?[/quote]

Slow cure foodsafe resin, poured and set for a week. I've done it in a different variation with excellent results, but the process just to make the blank took far too long to be profitable. If this bond is adequate, I'll be able to produce them.
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Posaunus
Posts: 5018
Joined: Mar 23, 2018

by Posaunus »

I think you can readily purchase off-the-shelf polycarbonate rod stock in appropriate diameter, as Doug Elliott must do for his rims. Possible alternates: Delrin, ABS. :idk:
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LIBrassCo
Posts: 585
Joined: Feb 24, 2019

by LIBrassCo »

[quote="Posaunus"]I think you can readily purchase off-the-shelf polycarbonate rod stock in appropriate diameter, as Doug Elliott must do for his rims. Possible alternates: Delrin, ABS. :idk:[/quote]

Sure, but this is made as one piece and more than just the rim. Goes .75" into the mouthpiece. Plus, it looks sexy.
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robcat2075
Posts: 1867
Joined: Sep 03, 2018

by robcat2075 »

Looks snazzy!
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LIBrassCo
Posts: 585
Joined: Feb 24, 2019

by LIBrassCo »

Was able to optimize the full resin top with metal core method as well. This is a tenor or thin rim bass blank ready to cut.
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trombonedemon
Posts: 218
Joined: Aug 06, 2018

by trombonedemon »

Darn, you need an apprentice to teach that too.
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LIBrassCo
Posts: 585
Joined: Feb 24, 2019

by LIBrassCo »

[quote="trombonedemon"]Darn, you need an apprentice to teach that too.[/quote]

Lol. Heres the final product
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Posaunus
Posts: 5018
Joined: Mar 23, 2018

by Posaunus »

Is the (beautiful) resin cup threaded onto the shank?
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LIBrassCo
Posts: 585
Joined: Feb 24, 2019

by LIBrassCo »

[quote="Posaunus"]Is the (beautiful) resin cup threaded onto the shank?[/quote]

Yup. There's a piece of metal thats set in the resin when its poured. That's whats threaded.
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elmsandr
Posts: 1373
Joined: Mar 23, 2018

by elmsandr »

[quote="LIBrassCo"]<QUOTE author="Posaunus" post_id="190744" time="1665526322" user_id="158">
Is the (beautiful) resin cup threaded onto the shank?[/quote]

Yup. There's a piece of metal thats set in the resin when its poured. That's whats threaded.
</QUOTE>
To make sure I understand, you overmold the resin on the threads? Or do you thread both and join them?

(I always love the process nuances)

Cheers,

Andy
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LIBrassCo
Posts: 585
Joined: Feb 24, 2019

by LIBrassCo »

[quote="elmsandr"]<QUOTE author="LIBrassCo" post_id="190749" time="1665528968" user_id="4931">

Yup. There's a piece of metal thats set in the resin when its poured. That's whats threaded.[/quote]
To make sure I understand, you overmold the resin on the threads? Or do you thread both and join them?

(I always love the process nuances)

Cheers,

Andy
</QUOTE>

Well since u asked....

I cut a piece of metal (bronze, brass, nickel silver, etc) to .7" diameter and 1.25" long. On the bottom it is threaded but not drilled past the threaded area. Then I make a wood disc thats 1.85" dia and .25" thick, to press onto the bottom on the metal core. This is used to center the metal in the resin, and provide a hard bottom to my makeshift mold. I then take a buttload (technical term) of blue tape and make a cylindrical mold out of it. At this point i mix up 105 grams of 2:1 resin, adding whatever color and flake tickles my fancy, stirring with a drill for 5ish minutes. After carefully pouring it into the mold, I run it through a bunch of vacuum cycles to pull the air out. Takes about an hour to get it all out. It then sits for 7 days, then is demolded. I screw it into a fixture, and cut the whole thing down to a working dimension.
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robcat2075
Posts: 1867
Joined: Sep 03, 2018

by robcat2075 »

It brings to mind some very old mouthpieces that were turned out of ivory.

Since you are doing semi-transparent version I think some embedded LEDs that flashed to sounds to be the next step.
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hornbuilder
Posts: 1384
Joined: May 02, 2018

by hornbuilder »

No allergy issues with the metal flake?
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LIBrassCo
Posts: 585
Joined: Feb 24, 2019

by LIBrassCo »

[quote="hornbuilder"]No allergy issues with the metal flake?[/quote]

If it was a concern I can simply not use any. Just a little color and good to go.
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hornbuilder
Posts: 1384
Joined: May 02, 2018

by hornbuilder »

<EMOJI seq="1f44d" tseq="1f44d">👍</EMOJI>
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LIBrassCo
Posts: 585
Joined: Feb 24, 2019

by LIBrassCo »

[quote="hornbuilder"]No allergy issues with the metal flake?[/quote]

And here's what that looks like. No coloring or metal flake.
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Vegastokc
Posts: 211
Joined: Jun 15, 2018

by Vegastokc »

Very cool. :good: