Even though I have not drilled any motors in 20 years, I do have a ton of B4-2 and B4-6 motors.
May have to get out the pin-vise and make a few "B14-2's and 6's"

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When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, TURMOIL, FIASCOS, and HAVOC !

.....But, but, but, it's soooooo much fun to beat the dead horse, it does not try to get away.......

Don't watch too closely--"Lookie-Lous" deserve whatever reactions they get from those whose affairs they butt into...

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Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
http://www.lulu.com/content/paperba...an-form/8075185
http://www.lulu.com/product/cd/what...of-2%29/6122050
http://www.lulu.com/product/cd/what...of-2%29/6126511
All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com.
NAR #54895 SR

Thank you for providing the one bit of information I needed! (I thought it was the case, but reading this from you clinches it.) Instead of petitioning the powers-that-be, ignore them and DIY thine own core-burning black powder motors. A suitable drill fixture (to enable those who lack drill presses) to drill their own core-burning motors might be made in...Oh, maybe Claremont, California, and folks who want core-burners could make as many as they want! (The drill bit could be the "pre-set drill depth" type that's used for drilling aircraft fuselage panels--my father found them very useful for precision woodwork.) Taking a few basic safety precautions would ensure that it would be very safe. Also:

While such motors wouldn't be eligible for use at NAR-sanctioned events (although "creative reliverying" could get them into the old motor program, if desired), the vast majority of model rockets are flown by individuals or groups who seldom have anything to do with the NAR, so what they might think of this is irrelevant. I just have no patience anymore for rules without *real* reasons. Since one of your DIY B14s will perform as well as an old, purpose-made Centuri or Estes B14, the fact that your motor lacks the "official stamp of approval" and the other one has it means nothing to me. "Will it work, with the same reliability and with the same [or very similar] thrust-time curve as a purpose-made B14?" is the only question which matters here.

__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
http://www.lulu.com/content/paperba...an-form/8075185
http://www.lulu.com/product/cd/what...of-2%29/6122050
http://www.lulu.com/product/cd/what...of-2%29/6126511
All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com.
NAR #54895 SR

I sense summoning. My tooling vendor could easily custom make such an animal and if GH and a couple others would provide me the precise diameter and depth of the core and the precise diameter and taper of the throat and exit, it would be trivial to make tools for whoever wants them. I suppose one could also modify E9's to D30's as well. I have lost all of my mod notes from the 1970's.

Jerry

I don't care if you drill your motors yourself on your own property. I do ask that when you light the house on fire you tell the fire department it was careless disposal of smoking materials. There's no better way to get an unwanted regulation that to do something stupid and have it hit the news.


Keep in mind that there have been professionals hurt and killed making motors. The process is not without risks.


And if you drill a deeper core in an E9 I'm pretty sure you can count on having it cato.

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Bill Spadafora
http://www.billsplumbing.com
billspad@comcast.net bill@billsplumbing.com

The ONLY ones I'm considering are B4's and not as some sort of 'experiment'.
Drilled B4's replicate original B14's. The nozzle is exactly the same and so are the motors; one has a drilled core and the other does not.
I just have to measure the right depth and core diameter of one of my old B14-0/5/6/7's

As a side note, the last produced B14's (somewhere around '79) don't have drilled cores and are exactly the same as the later B8's with a short 'pintle pressed' core. They perform noticeably different than original drilled B14's.

__________________
When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, TURMOIL, FIASCOS, and HAVOC !

Yeah, it almost looks like they were still calling them B14's for a while after going to the smaller (B8) core. One difference I did notice was that the smaller core B14 was deeper (0.75") than the later B8 (0.6"). Doug .



.

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YORF member #11

A few thoughts on this. One, if I was going to mess around with coring, I'd make a polycarbonate shield to put between me and the motor. And I'd wear some serious protection gear including polycarbonate face shield, welding gloves up to my elbows, and a blacksmith's overalls.

My idea was to rig a hand cranked drill thru the polycarbonate and have a way to hold the motor hands-free.

Another idea was to use conical drill bits. You can get these at the finer woodworking shops. I'd buy 2 or 3 different sized bits and experiment to see which one works best.

Lastly, for boosters, I'd start with C6-0's. They have more powder in them, so there's less chance of drilling thru the backside.

Again, this is all pie-in-the-sky thinking. I haven't even begun to assemble any parts. Althought I've ogled the conical bits at the woodworking store

Doug

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YORF member #11

I have done it in the past with a small drill bit in a hand-held pin-vise (slow and tedious) and with the same bit in a drill press set on very slow speed.
No mamby-pamby lexan blast-shield or any other safety GARBAGE other than a pair of safety goggles.
I would not reccommend this to anyone else, but I'm very careful and it was PLENTY of gear for me.

Back in the 'good old days' NAR even approved of one making their own BP motors with a press.
We need to get back to the 'almost NO rules' policies; If it's FUN and you hurt nobody ELSE, it's ALL GOOD.
In my book, No harm ALWAYS= NO FOUL !

__________________
When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, TURMOIL, FIASCOS, and HAVOC !