Aerotech K1103X with plugged forward closure no anchor

The Rocketry Forum

Help Support The Rocketry Forum:

mpitfield

Moderator
Staff member
TRF Lifetime Supporter
Global Mod
Joined
Jul 7, 2013
Messages
4,904
Reaction score
432
Location
Toronto, Ontario
I am just assembling an Aerotech K1103X motor, and the instructions do not deal with a plugged forward closure. Do I assemble it as per the instructions, treating the delay grain like a smoke grain, no drill out for time adjusting and obviously leave out the BP? If so, what about the forward delay spacer, will it fit, I am also inclined to grease the forward closure. One other thing I noticed is that the forward closures advertised for sale these days are standard and plugged but threaded? I was going to use my non-threaded, any reason why I shouldn't? I do have the plugged threaded as well, so it's no issue to just use it.
 

tbonerocketeer

Sponsor
TRF Sponsor
TRF Supporter
Joined
Jan 19, 2009
Messages
2,581
Reaction score
134
I am just assembling an Aerotech K1103X motor, and the instructions do not deal with a plugged forward closure. Do I assemble it as per the instructions, treating the delay grain like a smoke grain, no drill out for time adjusting and obviously leave out the BP? If so, what about the forward delay spacer, will it fit, I am also inclined to grease the forward closure. One other thing I noticed is that the forward closures advertised for sale these days are standard and plugged but threaded? I was going to use my non-threaded, any reason why I shouldn't? I do have the plugged threaded as well, so it's no issue to just use it.
Just build like normal, no drilling.you will still use the forward spacer in the same spot.
 

mpitfield

Moderator
Staff member
TRF Lifetime Supporter
Global Mod
Joined
Jul 7, 2013
Messages
4,904
Reaction score
432
Location
Toronto, Ontario
Thx Chris. It would be nice if they just included that part in the instructions.
 

mikec

Well-Known Member
Joined
May 9, 2009
Messages
2,524
Reaction score
392
AFAIK there's never any assembly difference between a non-plugged closure and the equivalent plugged closure, except you can't put BP in a plugged closure since there's no place for it to go.
 

woferry

Well-Known Member
Joined
Oct 9, 2013
Messages
806
Reaction score
27
Location
San Jose, CA
AFAIK there's never any assembly difference between a non-plugged closure and the equivalent plugged closure, except you can't put BP in a plugged closure since there's no place for it to go.
Not true for some AT 38mm plugged closures, they have a lip at the top that prevents the normal flat washer or delay O-ring from being used. But that's the only difference I've seen. I realize we're talking 54mm in the case of the K1103X.
 

Flyfalcons

Well-Known Member
Joined
Apr 14, 2015
Messages
2,523
Reaction score
736
Just flew a K1103X in a 54/1706 with plugged closure last weekend. What a great motor! Took my 5.5", 16.5lb rocket to 3536'. I thought it would be more of a lob but that motor pushed it with real authority. Yes, be sure to install the forward delay assembly as usual.
 
Last edited:

DavidMcCann

Well-Known Member
Joined
May 15, 2016
Messages
2,656
Reaction score
169
I've flown a K805G and K1100T with plugged, non threaded forward closures and built as normal, omitting BP.
 

mikec

Well-Known Member
Joined
May 9, 2009
Messages
2,524
Reaction score
392
Not true for some AT 38mm plugged closures, they have a lip at the top that prevents the normal flat washer or delay O-ring from being used.
Really? Which one? There are five 38mm forward closures on the current AT price list (floating, plugged, plugged/threaded, and endburn-style plugged/threaded) and of course the classic non-floating forward closure that no longer seems to be on the price list, and I would expect all of these to be assembly-compatible except the endburn style. Of course there have been a lot of variations in hardware over the years.
 

mpitfield

Moderator
Staff member
TRF Lifetime Supporter
Global Mod
Joined
Jul 7, 2013
Messages
4,904
Reaction score
432
Location
Toronto, Ontario
Just flew a K1103X in a 54/1706 with plugged closure last weekend. What a great motor! Took my 5.5", 16.5lb rocket to 3536'. I thought it would be more of a lob but that motor pushed it with real authority. Yes, be sure to install the forward delay assembly as usual.
Well, it lite without issue. Great motor, actually a really nice motor and a must launch again. It pushed my 3" Darkstar (13.4lbs) to 8,270' AGL..." with real authority"!

NYPOWER22_K1103.jpg
 

plugger

Well-Known Member
Joined
May 1, 2009
Messages
541
Reaction score
231
IIRC there are two types of plugged forward closures in 54mm. One is "half height" from a delay grain height perspective, the other is a "full height". Years and years ago we had a guy come from NSW to attempt his L2 at our annual big event. He soon realised his chosen reload delay was half height and yet he had a full height forward closure. He made up the difference by stacking Australian 20 cent pieces in the forward closure above the delay. It worked a treat.
 

mikec

Well-Known Member
Joined
May 9, 2009
Messages
2,524
Reaction score
392
IIRC there are two types of plugged forward closures in 54mm.
Yes, standard and extended. The extended is used for various long-burn motors like J90W, J135W, K185W, as called out in the instructions. K1103 uses standard.
 
Top