Max weight on a Pro38 G69...?

Building an Loc ISP for my level one. it weights in at around 2.5 pounds. is this too heavy for a Pro38 G69?
thanks
matt

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according to the Pro38-XX Motor Reference, the 133G69-12A 62.5g "Classic" G69-12A ,the Max launch weight is 2.97 lbs.... so you are close..... shockie B)

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shockwaveriderz wrote:

that is actually a significant safety margin. The max launch weight I provided is calculated using the 5:1 rule, which is very conservative, especially since it is a regressive burn providing a bit more power off the rail.
see thrust curve at
http://www.pro38.com/curves/133G69.jpg
I have heard of acceptable ratios as low as 3:1, but under ideal conditions (length of launch rod, zero wind, good stability).
IMO a 5:1 will be fine even in moderate wind ( < 15-20 mph is my guess at max weight )
what say ye merry gentlemen?
- iz
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MLOW is typically 3:1 (a legal principal not a practical principal)
My recommended "range" is 3:1 to 5:1. 5:1 is FAST.
Anything higher is just rediculous!
I know. Been there, done that!
Jerry

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Jerry Irvine, Box 1242, Claremont, California 91711 USA
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snip

30:1 is really cool
(as long as it's not pointed at people, buildings or vehicles)
-- Eric Benner TRA # 8975 L2 NAR # 79398
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wrote:

Please cite a reference to 3:! MROW as a legal princple (or even a princpal).

But that hadly matters as you are not manufacturing certified motors. ;)

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I have been used as a "consultant" to generate MLOW tables for several manufacturers (AT, USR, IBCo, CD, RDS, others). It is a judgement call, but here are my GENERAL criteria:
Thrust times 2 seconds or less 3:1 Thrust times 2.01-9 sec 4:1 Thrust times 9+ sec 5:1
The problem arises in estimating the DIAMETER of the MODAL rocket to be flown with a particular motor. So I cheat a bit. I assume a smaller modal diameter for long delays and a larger modal diameter for shorter delays.
Jerry
PLEASE pardon the tech post.
--
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Jerry Irvine wrote:

this man has a contribution to make ...
and makes it!
except to those who refuse it, which is their loss, IMO
tech post all you like, Jerry :)
- iz
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<< this man has a contribution to make ... and makes it! except to those who refuse it, which is their loss, IMO>>
Is anyone trying to stop him? Jerry is just as free as anyone else to make technical contributions to the hobby.
<<tech post all you like, Jerry >>
I agree.
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snipped-for-privacy@aol.com (RayDunakin) wrote:

But not "certified" contributions Not "participatory member contributons".
That is a HUGE exclusionary zone for someone politically inclined.

--
Jerry Irvine, Box 1242, Claremont, California 91711 USA
Opinion, the whole thing. <mail to: snipped-for-privacy@gte.net>
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RayDunakin wrote:

just don't make them on ROL, or TRA list, right? :(
- iz
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<< just don't make them on ROL, or TRA list, right? >>
No one is barred from those forums for making technical posts.
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RayDunakin wrote:

ah, too subtle for you, eh, Ray?
- iz
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<< ah, too subtle for you, eh, Ray? >>
No. You implied that Jerry is being barred from making technical posts on those other forums, and that others are to blame for this. He is being barred for other reasons. If he had stuck to making technical posts, he would never have been barred. He alone is responsible for his actions and the results of his actions.
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snipped-for-privacy@aol.com (RayDunakin) wrote:

Never disagree on principal and testimony with the sysop or moderator?
The guy who AUTHORED the ROL Jerry-page.
Just for the record.
Jerry
--
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snipped-for-privacy@aol.com (RayDunakin) wrote:

I am barred from those forums -to- make tech posts.
--
Jerry Irvine, Box 1242, Claremont, California 91711 USA
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On 11 Jan 2004 09:56:07 GMT, snipped-for-privacy@aol.com (RayDunakin) wrote:

Actually, everyone who is not a TRA member is barred from the TRA list.
Bob
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"a financial member" a special everyone but Jerry class was formed specifically to get around the fact I have been promised a membership refund I have not received yet. Until it is paid I am a "pending member". So they created a new class called "financial member" defined as "currently paid in full" as a criterion for TRA list membership.
Not sure how legal that is, but ethical it is not. After all, why not just refund the owed money plus interest since 3-92 and be done with it?
Jerry
--
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assuming : thrust times =< 2 s = hi thrust thrust times >2 <=9 s = med thrust thrust times > 9 s = low thrust what actual average thrust values correspond to the above ? most HPR are med to hi at least.... I would suspect your values would be different for LowMR.......
shockie B)

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Since all MR is in catagory 1, it was an "art" to add catagories 2 and 3.
I did that.
Both the subject matter in the form of products, a magazine to promote it, and a dealer network to offer them.
The post facto analysis was from observations of the artwork and subject matter in use in actual practice. Field experience.
Jerry

--
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