LOC IV Level 1 Certification Data Gathering

Hey Everyone!
I am so happy that I was selected in the "Certify With Us" program!

Thanks again to Kevin and Jeroen and anyone else that is involved in the program!!

I am planning on building a LOC IV and flying it with one of the H reloads.
I have worked up two designs for the project. Both are using baffle systems.

I am posting the OpenRocket files for both designs.

1. The first is basically the stock LOC IV with a baffle inserted into the upper half of the body tube. I will use the kit parachute with 15 to 20 feet of 1/2" tubular nylon for the shock cord. I am also considering modifying the fins to bring them even with the edge of the bottom of the body tube.

2. The second is a zipperless design with a baffle. The baffle is mounted extending from the top of the lower body tube. The upper section would be 14 to 16 inches of the 3.9" body tube and stock nose cone. The recovery gear will be the same as the other design, the kit parachute with 15 to 20 feet of 1/2" tubular nylon. This design also would have the modified fins.

I have been reading alot on the forum and other web sites for information and photos of the LOC IV. I have used this information to set up the two designs with the few "problem areas" of the LOC IV taken into consideration.

This thread is for more information gathering and suggestions from the rocket gurus on TRF. I am ready to order the kit and materials. When it arrives I will start my official "Certify With Us" build thread.

Thanks everyone!

View attachment Loc IV Long ALB LVL1.ork

View attachment Loc IV ALB LVL1.ork

I'll agree the swept back LOC IV fins are the Achilles heel of this kit. I've lost one of my own, although it was due to a broken shock cord.

My replacement LOC IV got some tip to tip fiberglass on the fins. Its still light enough to fly on G's, but really loves the H148R motors.

neond7 said:

I'll agree the swept back LOC IV fins are the Achilles heel of this kit. I've lost one of my own, although it was due to a broken shock cord.

My replacement LOC IV got some tip to tip fiberglass on the fins. Its still light enough to fly on G's, but really loves the H148R motors.

Click to expand...

Yes, the fins are really the biggest concern.

I am going to get the 29mm motor adapter also, because flying on smaller motors is one of the reasons I like this kit.

Ordered the LOC IV from Performance Hobbies this morning !

I ordered the LOC IV last night from Heavenly Hobbies and also got the 29mm LOC adaptor.
I too will consider doing something to the fins for added strength and using a different shock
cord. Maybe Kevlar long enough to extend outside the tube then Nylon...

Allen. You got any photos for us?

JP

No photos, yet. Still waiting for the kit to arrive.

This thread was for any pre-build suggestions from the forum.

When the kit comes in, I am going to start my official build thread.

Aero Antics said:

No photos, yet. Still waiting for the kit to arrive.

This thread was for any pre-build suggestions from the forum.

When the kit comes in, I am going to start my official build thread.

Click to expand...

Roger that.
I'm like you, I've been getting tips on the build as well.
I've been considering using a small diameter KEVLAR, making a 4 line harness coming off of the
top centering ring forming into one line near the top of the body tube. https://aeroconsystems.com/cart/launch-and-recovery-accessories/kevlar-tape-for-recovery-bridles/ Good price on KEVLAR. This way would make it less prone to putting a zipper
in the tube. I saw this in the forums somewhere...

JP

Even though the fins hand down low and can impact on landing, it is one tough bird!

Mine has landing HARD on concrete, only damage was cosmetic to the bottom of the fins, and little sanding and some new paint and you can only tell by very close inspection!!

qquake2k said:

I built my LOC-IV stock, and did break a fin on one launch. I repaired it and it flew again. I have since built several 4" rockets with a zipperless design. Here is how I do the baffles:

https://www.rocketryforum.com/showt...r-boring-HP-scratch-build&p=281373#post281373

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Thanks for the link to the build thread, qq.
I read through your LOC IV thread, too.

Aero Antics said:

Thanks for the link to the build thread, qq.
I read through your LOC IV thread, too.

Click to expand...

Here is the damage mine sustained.

Here is the last flight of my original LOC-IV.

https://www.youtube.com/watch?v=waS36Mi5ezw

Please note, unlike the commentary in the video suggests, I did not improperly tie the shock cord to the mount. It burned through and the body plummeted to Earth and snapped a fin and the nose cone/parachute floated gently back to Earth a few minutes later.

I've since replaced mine with both a "real" LOC-IV and a clone made out of leftover Blue tube that I had from another project (although 2 inches shorter). I used the nose cone from the broken LOC-IV on the clone. Both of them got fiberglass on the fins.

neond7 said:

Here is the last flight of my original LOC-IV.

https://www.youtube.com/watch?v=waS36Mi5ezw

Please note, unlike the commentary in the video suggests, I did not improperly tie the shock cord to the mount. It burned through and the body plummeted to Earth and snapped a fin and the nose cone/parachute floated gently back to Earth a few minutes later.

I've since replaced mine with both a "real" LOC-IV and a clone made out of leftover Blue tube that I had from another project (although 2 inches shorter). I used the nose cone from the broken LOC-IV on the clone. Both of them got fiberglass on the fins.

Click to expand...

Watching that gave me a sharp pain.

Here my second launch, skip ahead to the 1 minute mark, our RSO was new on the job and this was the first HPR of the day to fly, sorry about all the chatter...

[video=youtube;xVdHHbCvxfo]https://www.youtube.com/watch?v=xVdHHbCvxfo[/video]

Spooks said:

Here my second launch, skip ahead to the 1 minute mark, our RSO was new on the job and this was the first HPR of the day to fly, sorry about all the chatter...

Click to expand...

Nice flight. That sure was a loud motor, what was it?

A CTI Skidmark, H123, think it was louder because of the concrete around the pad area.

Spooks said:

A CTI Skidmark, H123, think it was louder because of the concrete around the pad area.

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Skids are very loud indeed.

Yes sir and I love flyin em!!

Can't wait to fly my Magnum on a 54mm skid!!

Sorry, didn't intend to hijack the thread, your gonna LOVE your LOC IV, mine is my fav...next up a smoky sam on an H and then an I!!

Spooks said:

Sorry, didn't intend to hijack the thread, your gonna LOVE your LOC IV, mine is my fav...next up a smoky sam on an H and then an I!!

Click to expand...

Not a problem!
A little side track in a conversation can reveal some great info. I know a bit more about motors now.

It is a great kit. I enjoyed building it. Good luck with you level 1.

Actually, just having a broken fin isn't too bad and not that hard to fix. The last time I saw a rocket that size with a broken shock cord was a G-Force. Its lower section came down ballistic and bounced off the top of the dash of one of the pickup trucks at the launch. Of course, it went through the windshield first. The fins were ok, but the BT was 75% shorter.

I used a LOC IV for my level one last spring. I had originally used wood glue on the entire thing, but on the cert flight it came down on the runway at Bong and knocked a fin a little loose (not enough to disqualify me). I launched it again at Midwest Power after redoing all the fillets with wood glue again, and this time one of the fins popped out after landing in the field. Moral of the story? Use epoxy on the fins, 5 minute is plenty fine.

Also I would recommend replacing the recovery system with Kevlar and an eye bolts. I used a payload bay from LOC to altimeters and other physics projects.

About 2000 feet with a AT 123 (5 lbs), and 1000 feet with a CTI H87 (3lbs, 29mm conversion).

Good luck!

Still waiting on the IV to arrive. Can't wait to get the kit and build thread started.