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View Poll Results: What SU BP motor is most needed ?
18mm B14-x/B8-x with at least delays of 0,3,5,7 16 40.00%
18mm C5-x 11 27.50%
24mm D20-x 3 7.50%
29mm E/F50-x 2 5.00%
13mm B4-x 5 12.50%
13mm 1/2A3-0T 2 5.00%
18mm D8-x like the old Cox 13n-sec D8-0/3 1 2.50%
Voters: 40. You may not vote on this poll

 
 
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  #21  
Old 10-26-2018, 07:52 PM
Doug Sams's Avatar
Doug Sams Doug Sams is offline
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Quote:
Originally Posted by tbzep
However, it would be nice for Estes to set aside a day or two out of the year to run one batch of B8's, D20's or whatever niche motors they choose.
If it were that easy, it might be worth it to them. But, in my experiences changing over a line from one product to another, the recipe is not guaranteed - it can take several false starts along with a few tweaks to get everything running just right.

If you're running a batch of C6's, where there may be a week or more of production, a day of re-tooling the line can be amortized pretty easily. OTOH, you can't afford a day of re-tooling for a half-day's worth of D8's, for example - the changeover cost will kill the pricing.

That is, I don't think motor making is an exact science, altho it surely is rocket science Anyway, I suspect the amount of tweaking required for some of the exotic motors will be a deal breaker too often.

I would envision something like running a hundred motors, spending a couple hours testing them, then adjusting propellant mix / tamping force / delay amount / etc, followed by another hundred units and a couple more hours testing. And that's for a well known product like a C6 or B6. It could take much longer for a D8 or D20.

Now, if the process could indeed be controlled so tightly that they can just throw a switch and convert from B6's to D8's, I agree, a day's production of this niche motor could probably be profitable.

OTOH, what about the batches that make it thru the two hour testing, then reach the market place only to later show some undiscovered issues resulting in a recall? That's the other issue with running small batches of niche motors, the risk of quality issues will invariably be higher.

I'm not wanting to be negative, but, from a marketing perspective, it's hard to make a good case for most of these.
...


One thought, first shown to me by Carl at NARCON in Austin back in 2003, was the BP motors with glued in delay elements. If the technology could be mastered such that these could be made very reliable, then the volumes could be grouped together such that the numbers would be high enough to justify production.

For example, in end-burning BP motors, an 8-second delay is an 8-second delay - the delay's burn rate doesn't vary as it does with composite motors. So a production of 8-second delays would be shared over E9-8's and D12-8's and C5-8's etc.

On the other end, the stamped motors would all be -0's . So all the D8's - D8-0, D8-4, D8-6 and D8-8 - would share the same batch of D8-0's thereby increasing the volume of that motor unit, and hopefully making the volume high enough to overcome the setup charges.

In short, if the BP motor supply morphed into booster motors with separate delay/ejection units, the numbers might make some of these niche motors much more realizable.

Doug


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