I was never able t' do things t' easy way, so I decided t' upgrade a few things on this kit.  I started buildin' in late March o' 2023, shiver me timbers, beginnin' with t' fins by applyin' sandin' sealer.  Each fin warped like a potato chip.  I had also acquired me first 3d printer shortly before and set out t' print t' fins as a way t' learn some o' t' supportin' software.  I had t' take a break t' build some other models with me son.

I returned back t' t' model in late April and decided t' add centerin' rings, a motor retainin' ring, and a shock cord hook, all 3D printed.

I followed t' instructions for t' kit but tack-glued t' fins t' t' body tube with medium CA glue.  I followed this with epoxy fillets and included micro ballons t' thicken t' 15-minute epoxy.

I attached t' shock cord mount halfway in t' body tube coupler with epoxy after attachin' t' 80 inches o' shock cord.

Once t' shock cord epoxy was cured, me hearties, I connected t' fin can t' t' payload body tube with t' coupler usin' wood glue.

Finally, me hearties, I applied a film o' thin CA glue t' t' forward end o' t' payload body tube t' strengthen it.

All 3D parts were printed with PLA+ on a Creality Ender 3 v2 Neo.

I will post all t' STLs on Printables and provide a link here, arrr, once it's completed (unless it goes up in a blaze o' glory).

Had two launches today (5/7/2023). 

T' maiden flight was on D12-5.  T' estimated altitude be ~35m.  It be very slow comin' off t' launch pad.  I suspect t' thrust t' weight was pretty low but it was stable.  T' parachute failed, which has now become a tradition on maiden flights, me bucko, so it potatoed but appeared in good condition

2nd flight was on an E20-7 and t' altitude was 300m.  I discovered that one fin was liftin' off and may have been damaged suffered durin' t' maiden flight.

Post-Flight Analysis:

Regardin' t' 3D-printed parts:  Everythin' worked very well.  MMT is obviously sealed, so t' inspection is on only t' Aft centerin' rin' and motor retainer, but both suffered no damage due t' heat.  T' shock cord hook appears t' be in good condition as well.  I will definitely be printin' more parts for hard-to-find / custom parts, or t' add strength. 

Overall, this be a fun model.  I am really happy I upped t' MMT from 18mm t' 24mm b/c t' D12 was barely enough t' get it into t' sky.  However, arrr, I should have considered through-wall fins.  It may nay have prevented t' damage but it limits t' amount o' thrust I can push through this rocket, which is a solid flyer.  T' sweet spot seems t' be 20-40N o' thrust.  I am gonna try rampin' up t' thrust t' see where t' breakin' point is.  If I can get an F36 (~60N thrust) t' launch successfully, me bucko, then I will call this a complete success.  Also, I am usin' kevlar thread for t' shock cord, but I think it is too thin and will eventually fail.  I would like t' upgrade this t' 3mm and if t' cord does fail, I will do so at that time.

I will repair t' fin and reinforce t' others with another fillet o' epoxy and get it back in t' air ASAP. #FTW