[F-FT] RMS delay question/comment

Nope. It may be "old school", but film suits me fine. Especially now that I can get my photos put on a CD at the same time I get prints made. The only real advantage digital cameras have at this point is the instant gratification factor.

Ouch!

Yet there hasn't been any test data released to back these claims up for over a decade. The actual delay values are a SECRET, contrary to NFPA requirements.

NO. They must be flown as submitted for testing. Uncertified delay combinations are not permitted.

In general there tend to not be delays that fall inbetween S and M or M and L for example Take for example the delays for the 29mm H128. The delay in an H128M would be a S in a G75, and a L in a H238. An H238S delay would be way to short in an H128 and eject before burnout in a G75. And if there were a delay for a G75L it would be an XXL in an H238, probably resulting in a lawn dart.

So there usually aren't delays "in between" the certified ones, just delays that are too short or too long to be useful for a given motor.

The solution is adjustable delays as certified with CTI motors...

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

Wrong again Jerry.

It HAS been submitted and certified for CTI. And long befire that Synerjet had a very nice delay adjustment tool, although I believe that predates motor certification. I still have mine!

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

Works for MOST delays, but not all of them. Particularly not the RMS delays with the black stripe on the tube, which have a different (slower?) burn rate.

This is not permitted at either an NAR or TRA launch. They WILL ask. Unless you LIE and claim that your H128-8 (uncertified cuz it was modified) is an H128-10. Lie to an RSO/SCO and prepare to be permanently booted out of every organized rocketry organization on the planet.

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

At a TRA (not EX) or NAR launch?

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

The bit size doesn't really matter. Neither does what side you drill (propellant side or ejection side). What matters is the total thickness at the minimum point.

And that a delay modified like this in the absence of manufacturer support (i.e. CTI delay adjustment tool) is an uncertified motor not permitted at any NAR or TRA launch. Fly elsewhere, and have at it.

In the past, before TRA motor certification, I've had 3 different manufacturers do this for me! Including the motor I used for my original cert flight in 1989.

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

The Synerjet tool was much smaller, perhaps 3/32"

Doesn't matter which side is drilled.

Yup. Many SU motors are made with LONG delays, then drilled down for shorter delays. The end result is some continued delay burn after ejection, dubbed the Hibachi effect because of what it does typically to small competition models (The Apogee/AT motors like the B7 were noted for this).

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

At the LMR end, absolutely correct.

AT stuff started showing up in Hobby Lobby stores across the country just before the fire. I hope you can get back in there and more. I don't think TRU et al is a viable market for LMR.

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

I'll bet the plywood is imported too. Here in the USA, we use ply from Scandaniva. What do you use for native glue? Vegamite? Perhaps a Diggerie-Do (sp) could be used for a native body tube :-)

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

-----snip-----

Yet if the manufacturer's would add a paragraph to the reload kit instructions detailing how to drill the delay grain to achieve the desired final delay during flight two things would happen:

and

John

Point.

1. Masking tape on the drill bit.

1. Calipers with depth guage and trial and error.

Slightly, less than 25% of the inherent delay error BTW.

You live in Kalifornia. You for one should be 100% convinced you are wrong.

Jerry

One of the many problems with Synerjet.

Only one motor per delay is required for HPR and I believe 3 for MR.

Point.

I guess they're probably imported to!!! I gotta get out of this country....(I luv it)

I use Spinifex (Grass) resin for glue.....have used Bees wax and gum tree sap also..... Emu tendons make great recovery lines and a sugar glider could be the parachute...........

A digery-doo.....Now that would be a cool rocket......Sure would make and interesting sound!!! I could use wattle leaves as fins and stick a Koala in the NC for a payload.....

Just great........now the greenies are after me....!!!

....

Is that to get caught mislabling them or to certify?