Thunderbolt Question

[AST128_RyanK]

Today a typical siren setup for a locality costs roughly $20,000 per siren. During the Cold War most sirens were purchased via Civil Defense funds.

Hypothetically if the thunderbolt was still on the market how much would a single siren setup cost?

[Stormsetter4]

If I remember correctly it was actually close to the 30-40k figure, I'll have to double check later but they weren't cheap.

[coastalsyrolover]

The thunderbolt is made of of multiple parts that you kinda are stuck paying for. The blower alone without the casing, frame, belts what have you (blower and motor) could cost you upward of 8 grand. (Depending on the blower and motor... Site is an IIRC from a distributor of gardener Denver... Oh and a bit OT but if you guys think the 6M blowers are big you should see the 8Ms...)

[QuantumCurse]

The thunderbolt is made of of multiple parts that you kinda are stuck paying for. The blower alone without the casing, frame, belts what have you (blower and motor) could cost you upward of 8 grand. (Depending on the blower and motor... Site is an IIRC from a distributor of gardener Denver... Oh and a bit OT but if you guys think the 6M blowers are big you should see the 8Ms...)

Whoa 8M? Does this even exist? How high did the numbers go?

[Snowcube]

How much did the head alone cost? It's just a model 2 in a can with a horn and rotator.

Why did the blower cost so much? It's just a centrifugal fan, it shouldn't cost that much...

[coastalsyrolover]

Yes 8M exists. The sutorbilt legend (blower the bolt uses) is its own blower. The thunderbolt just so happened to need the 6,5 and 4 M over its term. But yes they go up to and over 8M. No they are not centrifugal fans. They are positive displacement blowers. They move the air a certain way (IIRC) which is why a centrifugal based blower (like say... A leaf blower?) of the same specs makes such a cruddy blower. EDIT: I can't remember what the head costs... Best thing to do is find the model 2 part numbers (motor, armatures, chopper etc... Etc...) and add the prices up... IIRC jeb said the rotator motor is still made, the rotator belt gears are still made... The rotator belt itself is still made... But not by FS. Sorry I hope I don't sound cranky...

[EOWS1212man]

They are positive displacement blowers. They move the air a certain way (IIRC) which is why a centrifugal based blower (like say... A leaf blower?) of the same specs makes such a cruddy blower.

Yup. Instead of using an impeller like most conventional blowers, the thunderbolt "roots style" blowers use lobed rotors to create pressure. I am interested to see what would happen if you were to stick a finger or two into one of these things...



https://www.youtube.com/watch?v=_-fwWrFLiyY


https://www.youtube.com/watch?v=ZifVA3jWhno

[CDV777-1]

Today a typical siren setup for a locality costs roughly $20,000 per siren. During the Cold War most sirens were purchased via Civil Defense funds.

They weren't paid for completely with civil defense funds they were paid for with "matching funds". CD paid for half.

The Feb 1, 1979 Federal Price List AR-14 lists Thunderbolt prices as....

1000AT Two Tone 240 volt 3 phase $6684.25
1000AT Two Tone 240 volt single phase $7514.25
1003A 3-signal 240 volt 3 phase $6907.00
1003B 3-signal 240 volt single phase $7716.75

RCM1A for 3 phase thunderbolts $837.00
RCM1B for single phase thunderbolts $837.00

RCM3 for 1003s $236.00

If you use the inflation calculator online the price for a thunderbolt isn't much more than a current model siren.

[coastalsyrolover]

Or you could go with the prices above. Thanks CVD

[Snowcube]

They are positive displacement blowers. They move the air a certain way (IIRC) which is why a centrifugal based blower (like say... A leaf blower?) of the same specs makes such a cruddy blower.

Yup. Instead of using an impeller like most conventional blowers, the thunderbolt "roots style" blowers use lobed rotors to create pressure. I am interested to see what would happen if you were to stick a finger or two into one of these things...



https://www.youtube.com/watch?v=_-fwWrFLiyY


https://www.youtube.com/watch?v=ZifVA3jWhno

How exactly does that move nearly enough air to supercharge the siren? I can see it working great with water but with air it would be like using a huge metal ingot as a fan blade.