Definitely don't do that. Forward closure needs to be completely screwed down.Loosen the forward closer by about 2.5mm, screw down the aft closer by 2.5mm. You have now split the difference on both ends. Are the threads completely engaging on the forward and aft closers, if so you are good to go. If you are not completely satisfied call Aerotech customer service.
I've had this problem on multiple motors (usually 54mm ones). I did fly one successfully with a gap, but all the threads were engaged. Another I had the liner replaced by the on-site AT vendor.Definitely don't do that. Forward closure needs to be completely screwed down.
Some gap on the aft closure is fine; not sure whether amount you have is within that margin.
5mm is a bit bigger than 1/8in which is a little over 3mm. I would contact aero tech warranty, for what it's with the forward closure should ALWAYS be fully seated. If you're going to have a failure, it's much better the aft closure fails than the fore closure.Yes, 1/8” is fine. As you mentioned, we’ve been cutting the liners a bit longer to ensure that the forward seal disk has no room to move away from the liner. I will look at revising the instructions to note that a larger gap is acceptable.
I assembled a L1500T and there's a 5mm gap between the end of the case and aft closure. I cannot get it to go on any farther. Anyone else experienced this. I am not going to fly the motor.
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I bonded the grains into the liner as per the instructions.Aerotech has in their instructions to tighten the forward all the way down. There is a acceptable tolerance of +1/8" inch in the instructions. Are the grains still sliding free internally?
Ok , was not aware the L1500 was a bonded motor. The motor should be absolutely fine as long as the nozzle is tight and has no wiggle.I bonded the grains into the liner as per the instructions.
Send it. I flew an M-2225 SW with that much gap without issue. I made damn sure I felt o-ring compression on the aft closure (which I did), and that motor also required grain bonding. IIRC there was a post or two about AT cutting liners a little bit longer, but not finding those posts right now...I assembled a L1500T and there's a 5mm gap between the end of the case and aft closure. I cannot get it to go on any farther. Anyone else experienced this. I am not going to fly the motor.
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I spent several grand and over a year on this rocket... I don't want to be lamenting that if the rocket blows up.Send it. I flew an M-2225 SW with that much gap without issue. I made damn sure I felt o-ring compression on the aft closure (which I did), and that motor also required grain bonding. IIRC there was a post or two about AT cutting liners a little bit longer, but not finding those posts right now...
Karl will get back to you im sure.I spent several grand and over a year on this rocket... I don't want to be lamenting that if the rocket blows up.
I emailed AT warranty. I'll see what they say.
He did! To sum it up:Karl will get back to you im sure.
I'm hoping to see great pics of the flight!
Awesome, love it!He did! To sum it up:
* The FWD closure *must* be tightened all the way.
* The liners are a tiny bit longer now, and about 1/8" or slightly wider gap is normal.
* A strap wrench can be used to tighten it further. I did this and got one more mm (vertical) of engagement.
Nice !He did! To sum it up:
* The FWD closure *must* be tightened all the way.
* The liners are a tiny bit longer now, and about 1/8" or slightly wider gap is normal.
* A strap wrench can be used to tighten it further. I did this and got one more mm (vertical) of engagement.
Why wouldn't it be? The design of the motor didn't change simply because the liner is just a hair longer.Another question: is this motor still certified with this much a gap?
NEVER use a tool to tighten an Aerotech closure .I had the same issue with an L2500 I flew back in December even after tightening the aft closure with a strap wrench.
Please don't do this!!!!!!!!!!!! The forward closure NEEEDS to be tight.Loosen the forward closer by about 2.5mm, screw down the aft closer by 2.5mm. You have now split the difference on both ends. Are the threads completely engaging on the forward and aft closers, if so you are good to go. If you are not completely satisfied call Aerotech customer service.
Aerotech recommends using a strap wrench to tighten the aft closure.NEVER use a tool to tighten an Aerotech closure .
you will never gain anything good .
Aerotech recommends using a strap wrench to tighten the aft closure.
Had a similar 'issue' on the new AT N4000 and it flew just fine.
I think I found the root cause. I saved the spent L2500 reload parts so I measured it. The liner is 12.813", but the assembly drawing shows 12.688". For a comparison my M4500 liner is 18.75", which exactly matches the assemble drawing and is left with ~1/16 gap when the closure is tightened.Aerotech/RCS should publish a master list of liner lengths (and tolerances) per reload. And make a public announcement to allow end users to shorten the liner if it's too long. This would keep the modification within the rules for certified motors. If it's too short, send it back for warranty replacement.
How big was the gap? Was it over 1/8"?
The gap on my L1500T is over 1/8" with one full thread exposed. This is outside of AT specs. I do not think it's safe to fly, and several people at my club agreed when I showed them
Same here. I flew several AT 75 reloads this year with the longer liner and larger gap at the aft closure. I had the same concerns as OP when I first saw it but after AT said good to go, I flew the first one without issues and never looked back after that.Had a similar 'issue' on the new AT N4000 and it flew just fine.
Even after Karl said it was good to go, you still didn't feel comfortable flying it?How big was the gap? Was it over 1/8"?
The gap on my L1500T is over 1/8" with one full thread exposed. This is outside of AT specs. I do not think it's safe to fly, and several people at my club agreed when I showed them.
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