Loc Pk-66 Ultimate; Now a build thread w/pictures.

[Wallace]

Anybody have one? Clusters have always caught my attention.

The start of the build thread: https://www.rocketryforum.com/threads/loc-pk-66-ultimate-now-a-build-thread-w-pictures.146632/#post-1794780

 

[Wallace]

https://locprecision.com/product/pk-66-ultimate/

 

[jimzcatz]

First 4" rocket I ever bought,except the Estes Saturn V. What do you wanna know. Yes, it flies fine on 7 D12's

 

[heada]

Great kit. I fly mine on 6xF42 and 1xH180. It gets a good 30 feet up before the H comes up to pressure. The fin connection is weak, I have had 3 fins break loose now. You may want to re-enforce the fin joints.

 

[jimzcatz]

Never had that problem. I glued fins to mmt valleys and extended slots all the way to the rear. Installed fin/mmt assembly as one unit.

 

[Wallace]

Well....That's all good news because I impulsively oredered one. Assume woodglue and paint'll be fine?

 

[kuririn]

LOC used to have a download page with instructions for most of their kits. Seems to have disappeared, maybe the new owners took it down.

 

[Rocketjunkie]

I cloned one as the kit was OOP at the time. CRs not needed as the 7 29mm tubes fit a coupler perfectly. Slide coupler into airframe, cut fin slots and install fins. I added a single T-T layer of 3 oz glass. Mine is dual deploy and has a bulkhead in the booster for recovery attachment. Flies well to 950 feet on 7 Estes F15s. Havent tried anything beyond an I204, 2 H87, and 4 F15 yet (4000 feet).

 

[Wallace]

Any pics?

 

[Wallace]

1. 
2. 

PK-66 ULTIMATE

$109.95

Quantity
SKU: PK-66 Categories: Rockets, 4.00" Diameter, Retro

• Description
  
• Additional information
  
• Reviews (0)

Description
The Pk-66 Ultimate is an old LOC standard. Sporting 7x 29mm motor mounts, 6 fins and a payload. This kit is made to handle your transition into the cluster realm. One of the Retro series it’s not for the faint of heart. Light weight and made to punch a hole in the clouds!
All LOC/PRECISION 4″ Advanced series kits include heavy duty airframe and motor mount tubes, high-grade precision-cut plywood fins, centering rings, rip-stop nylon parachute or streamer, nylon webbing shock cord with sewn loops, and mount, launch lug, polypropolene nose cones and instructions.

 

[Wallace]

After literally hours of searching.....That is all I've found. Seems to be impervious to my ocdc...

 

[dhbarr]

Helpful?

 

[Wallace]

Very! Appears to be a nice strong stack. Assume it'll take whatever you can throw at it? Has it flown/did you add conduits for airstarts? Thanks for the pics btw...

 

[Wallace]

After finding my glasses; Are those printed centering rings?

 

[dhbarr]

Very! Appears to be a nice strong stack. Assume it'll take whatever you can throw at it? Has it flown/did you add conduits for airstarts? Thanks for the pics btw...

After finding my glasses; Are those printed centering rings?

3d printed yes, mine no. Those are from the forum here, but search engines haven't finished rebuilding after the changeover so I haven't tracked down the original post.

 

[Wallace]

Super cool. Assume the plywood rings are weak at best? ttw fins carry the load anyway?

 

[patelldp]

The mounts posted are mine...and yes, rings are 3D printed. Rocket hasn't flown.

 

[Rocketjunkie]

Any pics?

video on F15s

 

[Wallace]

Aye! 7 total bp f-15's ? Nice...

 

[jimzcatz]

No, not the fins. The load is carried by gluing the fins in the valleys between the mmt, then installing the mmt/fin assembly into the tube as one unit.

 

[markkoelsch]

No, not the fins. The load is carried by gluing the fins in the valleys between the mmt, then installing the mmt/fin assembly into the tube as one unit.

So, to clarify for the OP, you mean to extend the fin slots to the base of the airframe, then insert the entire motor mount/fin assembly into the airframe, correct?

 

[jimzcatz]

Well yea. Doesn't everyone? I mean it makes the most sense. Plus strongest method. I do that with every rocket I build.

 

[Wallace]

Exactly...I think. No thrust ring needed/wanted?

 

[Wallace]

Just wanted chime in to give props to LOC. My Ultimate arrived on Tuesday and after opening the box I discovered some damage. Unfortunately it was at the slotted end of the booster tube otherwise I'd have simply cut it off and moved on. Shot an email to customer service and got a reply from Jay almost immediately. 2 days later Priority Mail box with perfect replacement parts is at my door. Now that's how to run a business..

 

[new2hpr]

I've got one. Loves to eat G80s!
If you plan to use HP reload casings, be careful to open up the rings to give the motormount tubes a bit of room for the aft closures. Butting them tight won't work. Ditto on the suggestion to nest the fins between motor tubes. I did like the instructions (fins lined up on motor tubes and just through the airframe) and they frequently crack at the fillet.

 

[Wallace]

Yup. Good call on the motor mount(s). I do have a stash of G-80's for "fit up". I'm gonna try to keep it light, my tendencies are to completely over build everything. I was given a big bin of Mono Kote/iron/woodpecker, even a mini heatgun by fellow Trf'er cvanc that I've been looking for an excuse to put to use. Thanks Carl..

 

[Wallace]

Never had that problem. I glued fins to mmt valleys and extended slots all the way to the rear. Installed fin/mmt assembly as one unit.

Just realized the fin tabs are apparently short enough so it appears their intent is to mount them directly to the motor tubes, not the "gaps". Since I'm currently PC-less/no Open Rocket, any opinions on CP location if I "bury" the fins that much deeper into the airframe? Will it lose too much stability or would it just be easier to make new fins?

 

[Wallace]

Any opinions on fin material choice? I've pretty much decided to just re-make a set with .375" longer tabs to get them all the way into the mmt valleys without losing span by just burying the stockers deeper. They measure .120ish so probably 3mm 3 ply hobby plywood. I'm considering maybe using .90 G-10 to save some ass weight. Would that be a reasonable compromise between weight/stiffness? I will definitely build the can outside the airframe since it's my go to method, second being balsa strip fin pockets. I just think making (6 total) fin pockets that would have to fit/seal to the radius of the fin tubes would be just to damn time consuming.

 

[Wallace]

Ok, Looks like this is turning into a build "type" thread. Meaning I doubt I'll boar you with the entire process, just the juicy bits. Make sense? Since I intend to build my Ultimate dual deploy the cardboard coupler from Loc just wasn't gonna make the cut. Not that there's anything wrong with it if used as intended (glued in). What I needed was a real av bay/coupler. First thing I did was grab the 4" av bay outta my Mac Pluto SLAM. Rats, close, but too big on the o.d., no fit. I called Mike @ Mac Performance Thursday afternoon and asked him if he could make me a coupler and bulkplate combo that would work with my existing sled, just need a smaller o.d. to fit my Loc tubing. I gave him the dimensions and I'm fairly certain he had it completed before we finished our conversation. He got it in the mail an hour after we spoke, it showed up this morning and you couldn't get a better fit if you tried. Thanks Mike.

 

[Wallace]

I finally decided [/ATTACH] [/ATTACH]