Looking for info on piston for manufacture

A forum to facilitate discussion amongst Gamewell Diaphone (Fire Horn type Diaphone) enthusiasts.


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Joined:Fri Oct 26, 2018 4:18 am
Do you own a Diaphone?:Yes
Looking for info on piston for manufacture

Post by benscale160 » Thu Dec 06, 2018 7:02 pm

I am going to attempt to manufacture pistons.

Does anyone have a piston with the third ring with holes?

If so, I would like to know if you could share the following dimensions?

The width of the third ring

The width of the gap between the second and third ring

Any offset from bottom of piston motor section to the bottom of the third ring (hard to tell from pics if there is any)

Depth of the grove between the second and third ring

Number of holes

Hole diameter

Spacing of holes (distance between, distance from edge, diameter of center circle, will all work)

My piston and stator appear to be worn. About .006 clearance (that's equivalent to a 5/32 hole of blow by) So I'm gonna make another piston with the 3rd ring and hopefully get the growl.

Ran the horn with a diesel tow behind compressor supplying 110 psi at 100 cfm or so over the weekend. I played with the regulator pressure. Did not seem to make any difference on horn tone, sound or volume above 50 psi. Sounds like a very loud and good Leslie a-200.
Maybe that is how the 2 ring piston is suppose to sound, however, I'm after the growel.

So I'm gonna try and make a new piston before I upgrade my plumping to 1 1/2.

I bought enough aluminum to make 6 pistons (all 6 will prob not make it). When I get the recipe perfected, there will be some offered for sale. Depending upon demand, and other factors, I will consider making more.

I will also consider making them out of 932 bronze as well. However, the material cost is a lot more and will likely be two pieces silver soldered together.

I'm not promising anything just yet, but could I get a show of hands as to who might be interested?


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Joined:Tue Jan 28, 2003 2:41 pm
Do you own a Diaphone?:Yes
Location:Potter Valley, CA

Re: Looking for info on piston for manufacture

Post by Jim » Sat Dec 08, 2018 1:09 pm

What is "the growl"?

2 Honks
2 Honks
Joined:Sat Jun 05, 2010 12:39 am
Do you own a Diaphone?:Yes

Re: Looking for info on piston for manufacture

Post by geomaz35 » Tue Dec 11, 2018 10:14 am

I have available a few pistons. They are used aluminum ones that are still good replacements. These are from the six diaphones I had new bronze pistons made.
Buy the whole lot, keep the ones you need, sell the rest. There's always someone looking for a replacement piston.

I have about 8-10 diaphones in various condition & rarity that I'd like to sell, keeping just the two that originally come from my hometown.

Serious buyers with funds ready can contact me with needs.

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