LOC 4" Black Brant X L1 Cert Build

[PeterP]

Just started the build today. Got everything sanded down and rounded the fins. However, I’ve ran into the problem that the fin tabs seem to be too deep and therefore I can't insert the 54mm motor tube. The only solution I see is to just use a table saw and cut down the tabs till they are flush with the outside diameter of the motor tube. Before I do that though, I wanted to get your opinions on why this is and what to do. I attached photos below to clarify

 

[solid_fuel]

Was this kit offered with an option for 38mm or a 54 motor? That’s a pretty good amount of extra tab on the fin.

 

[PeterP]

Was this kit offered with an option for 38mm or a 54 motor? That’s a pretty good amount of extra tab on the fin.

Kit comes standard with a 54mm mount. It absolutely does look like the fins were cut for a 38mm tube. That is my guess on what happened and I will just have to cut down the extra tab

 

[solid_fuel]

At least it’s not too short.

 

[Scottrod]

I received a 4 inch loc iris on Thursday same thing with my time I called loc to let them know that they had an issue. I was going to cut them down myself but Jason said not to bother and shipped out another set . Should be here Monday. Great customer service.

 

[PeterP]

I received a 4 inch loc iris on Thursday same thing with my time I called loc to let them know that they had an issue. I was going to cut them down myself but Jason said not to bother and shipped out another set . Should be here Monday. Great customer service.

That’s interesting someone else had the same problem. I wonder what was going on with LOC. My kit also shipped without a motor tube entirely. No doubt, LOC does have awesome customer service though. I simply dont’t have the time to wait for a shipment to come in and can have my fins cut in a matter of time.

 

[solid_fuel]

Yeah if you have a saw handy it seems like it would take a matter of minutes to cut it to length.

 

[PeterP]

Just contacted LOC about fins. Turns out they did have an error while cutting and this was one of the kits affected! Nonetheless, it is a small hiccup in the build process. Moving forward!

 

[PeterP]

Fixed the fins today. Was a simple process and the cut was clean. A little sanding and it was a perfect fit! Up next, attaching them to the motor tube.

 

[solid_fuel]

nice work that is a good looking trim what kind of saw did you use?

 

[PeterP]

nice work that is a good looking trim what kind of saw did you use?

Thanks! Just a standard table saw. Set fence for 1/4” and adjusted for width of blade

 

[PeterP]

Motor tube/fins: Check! Going to let that cure overnight while I start working on the baffle system.

 

[PeterP]

Installed fin can into body tube and clamped the ends for a tight seal. Did an aft and forward fillet. Will do fin fillets once this cures.


Assembled baffle system. Epoxied threads on eyebolt to prevent future slippage.

 

[Nytrunner]

So far so good!

What's your retention scheme? Madcow plate or bolt-washers

Your epoxy application looks like my L1 and early use It'll get better in time

 

[PeterP]

So far so good!

What's your retention scheme? Madcow plate or bolt-washers

Your epoxy application looks like my L1 and early use It'll get better in time

Thanks! Motor retention is the standard LOC Z clip fasteners. About the epoxy...lol. Any tips/tricks or what I could improve on?

 

[Nytrunner]

None besides practice. Some folks use plastic spoons to shape, others a gloved fingertip dipped in alcohol, etc...
Really its just cosmetics and cleanliness that you acquire over time as your finesse increases. As long as the epoxy is where it needs to be for the joint, you're good.

My L1 was 5 minute Loctite HD applied via toothpick, so it had little drags and dips too! Still going strong, I'll probably throw a J at it sometime this year

 

[PeterP]

None besides practice. Some folks use plastic spoons to shape, others a gloved fingertip dipped in alcohol, etc...
Really its just cosmetics and cleanliness that you acquire over time as your finesse increases. As long as the epoxy is where it needs to be for the joint, you're good.

My L1 was 5 minute Loctite HD applied via toothpick, so it had little drags and dips too! Still going strong, I'll probably throw a J at it sometime this year

Nice. I’ve been using waffle batter cups from school and coffee stirrers from Starbucks for application. I’m probably going to tape the edges when I do the fin fillets just to try to get a better appearance. Glad I went with 30 min epoxy though, 5 min would stress me out haha

 

[PeterP]

Epoxied the baffle system in. Next is to epoxy the first payload section to the top of the baffle system.


Got the first payload section epoxied on and tacked the canards onto the body tube. Decided I’m going to wait until the near end to do fillets on fins/canards.

 

[PeterP]

Epoxied the bulkplate into payload section coupler and then coupler into the second payload. With that, that’s the final assembly for this kit and the only thing left to do is fillets and painting.


All assembled, this kit goes floor to ceiling


As far as fillets go: my plan is to tape off where I don’t want epoxy for clean lines, use 30 min BSI epoxy and lather on fillets. Once it begins to set, I will use a gloved finger and smooth them out to my liking. Are there any tips/tricks other than that?

Also, it’s nearly 100% chance of rain this Saturday. HARA hasn’t put out official word but I’m assuming the launch will be cancelled. That just means I can take more time perfecting the paint finish and really going over every detail before next months launch. Hoping to certify then.

 

[Nytrunner]

We will be discussing the launch at our meeting tomorrow night.

FYI, this is our last launch of the season for this field, unless we can secure permission for next weekend 3/16
(We're still in search of a summer flying field)

Hazards of winter flying fields in North AL, rain.......

 

[PeterP]

We will be discussing the launch at our meeting tomorrow night.

FYI, this is our last launch of the season for this field, unless we can secure permission for next weekend 3/16
(We're still in search of a summer flying field)

Hazards of winter flying fields in North AL, rain.......

Good to know! Hope a field is found for you guys soon. HARA is one of the closer clubs coming from Nashville, TN.

 

[PeterP]

Fillets are done! They didn’t turn out perfect but I’m pretty pleased with myself for it being one of my first times. With some sanding, they should look just fine

 

[PeterP]

Started painting the upper section. This aluminum metallic paint looks great!


Realized I needed to add the rail guides. Took me a few tries in the door frame to get a straight line, lol. All is well!

 

[Theory]

time to invest in a $3 piece of aluminum angle...

 

[solid_fuel]

Yeah the aluminum angle is a piece I use fairly often. So much easier than a door frame or drawer edge.

 

[PeterP]

Will definitely consider the angle on future builds. The rail buttons look straight enough this time though.

More on the build:
Got everything painted last night and let dry today while I worked on the sim


Next to Estes Amazon for scale


As far as the launch:
I will be on the lookout for near by launches that preferably have a vendor so I can avoid the Hazmat fee. Worse case scenario I can manage going over budget. If anyone has some they know of near Nashville, please share

 

[Nytrunner]

Nice paint. Thought it was a motor case at first.

As I'm sure you found out, weather has canceled launch today, and is looking like it will saturate the field for next week too...we wont know till Friday unfortunately

 

[Andrew_ASC]

None that I know of near Nashville other than HARA. I’m from Signal mountain,TN near Chattanooga. I also fly at HARA. There’s a university prof working with NAR, the FAA, a farm, and a club trying to set up another high power field but progress is slow. I graduated and have been out of loop for awhile with that.

As for dodging hazmat fees I picked a smaller 54mm short stubby scale rocket and motor Combo the Aerotech RMS 38/240 with H130W-14 USPS load. I had to add the file from thrustcurve to open rocket. You’ll want your rail exit velocity to exceed 45 feet per second I’ve had an RSO tell me from sims. It might be too small of a motor for your rocket. I think Aerotech also has a I180 38/360 hazmat free load.

 

[PeterP]

Update: Tomorrow is the day!!

Was informed by a fellow member that there was a launch in Kentucky tomorrow and Chris short will be the vendor. So I’m planning on hitting the road early tomorrow and going for my L1 certification. I took the past 2 days to do some finishing touches like vent holes, screwing nose cone in, friction fitting, and completing my simulation on OR. I feel confident in my build and hope it all goes smoothly. Plan is to use a 38mm I280DM which aims to about 2400 feet. If Chris is out of stock by the time I get there, I have a backup choice of an I500T. Will let you all know how it goes!

 

[Andrew_ASC]

Glad to see you found a motor vendor. I plan on driving up there also but may get there around 11am-11:30am ET? It’s a further drive from chatt. If I were you I’d double check all the recovery harnesses,knots, and chute packing only because it’s your first time doing it. And ask another flyer to check over it before it goes to the RSO table because they may catch an error you didn’t. The RSO may want to see the CP location on the rocket so mark it. I didn’t see any recovery gear photos in this build thread to critique.

I will say with your altitude you’ll have zero problems visually seeing it throughout the flight. I regularly fly to 2500ft. Most importantly have fun! Recovery failure is what generally gets someone on a cert flight. Best of luck to you.