Build Thread: Trivecta 318

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spigalau

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Thanks - We have a couple of chute options we can use whilst waiting on the proper ones - 12" & 18" that we got as drogues for our 3" project which we never used (went with a ballute instead).

I was trying to weigh the 318 last night, bottom section with harness was 196g, and was 30g on the nose section - I haven't added any forward weight yet.

We added another internal section at the top of each motor block (to stop motors going up the tubes) and added another internal section at the top of the tubes where the rail buttons attach. So with ours the rail buttons have 3 layers of fibreglass to bite on to, top & bottom.
 

Tractionengines

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@NateB & @spigalau

Quick questions... I just picked up a Trivecta 318 on the holiday sale. Got it today, and the 18mm tubes seem to be at the large end of the tolerance. (18mm Motors have a little wiggle room.) So the normally tight fit in the BT60 is a VERY tight fit, and I can't get the 3x centering rings over them at all. I am a little afraid the ring will split at the thin section if I force it .... Any thoughts? How tight were yours... I read you both said tight, but to what extent?

Also, attached is the new kit of parts. Note: there is a some additions, from your original photos:
(3) 18mm Motor blocks
(1) Centering ring BT-60:BT50 (My guess is for recovery attachment, and hard stop to the 3 motor tubes.)
(1) threaded Rod for motor retention (Like the bigger version in the video.)
20211203_135306.jpg

I was planing to get this together quick for a Christmas Gift, but don't want to rush if I need to make some adjustments. or get replacement 18mm motor tubes.
 

NateB

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I remember the 3 18mm tubes being a pretty tight fit inside the centering rings and the BT60 tubes. You can lightly sand the inside of the centering ring to fit. The 3 tubes needed some force to fit in the BT60 tubes as well. You can always lightly sand the contact points. It shouldn't take much to get a good, snug fit.
 

Tractionengines

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Thanks Nate. I hope you don't mind me hijacking your thread.

I was planning on a little sanding and just "force fit" the rings on... worst case even if a ring splits, the motor force is thru the (3) long tubes anyhow. The lower rings only give a little support to the body tube holding the fins.

I did update Nate's SIM file with the parts in the current kit. (Recovery [not part of kit] is 18" LOC Chute. I will use a 24" for open areas, or hard surfaces. The 18" looks to come down a little fast, but that's good with rocket eating trees all around.)
 

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