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End Burner vs. Gerb tooling


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This is probably a dumb question, but what is the difference between end burner rocket tooling and gerb tooling? The two toolings look very similar, yet if you look at Wolter or Ben Smith's websites there is a great disparity in the prices of the two. Some of the end burning tooling seemed to have a tapered interior and exterior, where the gerb tooling just had a tapered interior.
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Wish I had a good answer...when it comes to tooling, I am unconventional. For instance, I use one ram to make all my go getters...not a 3 or 4 piece set...work every time with all comps.

 

Most of my rocket tooling is firat turned out of hardwood...even the spindles. That way I can reduce or change the size of the spindle to work with the tube and comp. in use at the time. If I want to stay with one size and fuel, I turn the tools from aluminum or brass/bronze. I have one set of wood rammers I have used for years...still good as aluminum.

 

I'll watch here for an answer to your question...

 

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This is probably a dumb question, but what is the difference between end burner rocket tooling and gerb tooling? The two toolings look very similar, yet if you look at Wolter or Ben Smith's websites there is a great disparity in the prices of the two. Some of the end burning tooling seemed to have a tapered interior and exterior, where the gerb tooling just had a tapered interior.

 

it aint rocket science,people use to tell me you cant do this or that well just about everytime they were dead ass wrong.Theres alot of different opinions of designs,like thumb says i can adjust my spindles to work with the bp which is easier than the reverse.I guess all in all its up in the air mate

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gerb tooling can be used to make endburners, it depends whether you want a mediocre functioning rocket or one that can carry small loads,ive seen reports that suggest that they cant carry much past their own weight [these must have been made on sub optimal performce tools] mine can lift ten times the motor weight and some, i doubt this is scalable, i havnt seen the tools in question but if the nipplies are the same dia/length i would suspect the gerb to be super powerfull or the rocket weak depending which end of the scale they are, from what i know gerb tools have 1/3 id nipple/nozzle endburner tools have 1/4 mine use nearly one 5th the id but the hottest bp is a problem for some of my tubes with such small nozzles.

 

i would expect to pay more for rocket tools than gerbs it makes sense to charge more for what is in the most demand, but not fair, as for the tapering, the endburner can do with using the exhaust gasses to maximize thrust whereas its not really important for a gerb you would end up with a straighter higher spray, the gasses/metals only need to escape the tube and have no function other than looking nice

 

dan.

Edited by dan999ification
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The basic difference between a Gerb set and an endburner set is the nozzle. In the endburner set pictured below, the nozzle is about 3/16" and allows for a higher pressure to be created within the chamber which in turn becomes a higher thrust. The gerb set shows about a 1/4" nozzle and that allows for the expulsion of star chips, crackle and larger bits of metals without clogging the nozzle.

 

The actual thrust of the gerb should be 1:1 but no greater then 2:1 thrust to gerb weight so that a fountain of sorts is created and not a high velocity spray of sparks. Also lacking in the gerb set is a divergence since there is no desire for high velocity, no divergence is needed.

 

The actual price difference should be minimal between the two if any at all since the very same amount of turning time is required for both sets as well as base material.

 

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-dag

 

 

 

 

 

 

 

 

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Thanks a lot Dag. It was mostly the price difference that really struck me as odd. Both Rich and Ben sell 3/4" gerb tooling for around $70, but the corresponding rocket tooling is in the vicinity of $110. The gerb tooling actually has more base material as the rammers are longer. Who knows, it may just be old stock and the price has yet to catch up with the current market.

 

Basically the difference is the lack of the divergence and a slightly larger choke diameter. I've been thinking about getting some new tooling, and was going to hopefully kill two birds with one stone. I really want some driver tooling, but if I could combo it with end burners, it'd be all the better. It seems there isn't a solution that would work out. I could just drill out the nozzle on end burner tooling, but the rammers are generally going to be too short. Oh well. I'm leaning toward getting the end burner tooling, and just knock up some cheap wooden rammers to make gerbs and drivers with.

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I make dual-use sets that have one set of rammers and two spindles, one gerb and one end burner. Since both sets have the same convergence, there is no need to duplicate rammers. There is a some tendency when making endburners for the rammer to fill with clay and BP so extra attention must be paid when using the sets this way.

 

-dag

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