LOC-IV - Cloning an old friend

[chuck5395]

I started back into rocketry in the spring of 2009 with my then 17 year old son. We still fly rockets together today. While he does not enjoy the build process (I know, crazy). It's a good thing I do.

Below is the LOC-IV in its prime.


When we lost his first HPR rocket back in 2011 due to operator error, it was like losing an old friend. This rocket had been with us almost from the very start of our HPR journey. I vowed then and there to build another one, this time from scratch (my first).

Below is the LOC-IV as it is now.

 

[chuck5395]

I happened to have a 4" body tube, 38mm motor mount, and two centering rings (all from Binder Design) that I had purchased to repair a different rocket. Since I was able to salvage that rocket (and then fly it for my L2 cert), I had these parts just laying around. Add to it the nose cone from my Binder Thug, and I have pretty much everything I need.

 

[chuck5395]

This build, as was the original build, will incorporate some of the enhancements that qquake2k made to his LOC-IV kit.

First of those enhancements is the addition of a third centering ring. I made mine from 1/4 ply from Michaels. Unlike qquake2k, I use a circle cutter rather than a hole saw.


After I cut the ring out of the plywood sheet, I then adjust the circle cutter to make the hole for the motor mount tube.

 

[chuck5395]

Then it was back to the body tube to mark out the fin slots and rail button locations.

My handy-dandy Binder Design fin guide


I use a scrap piece of angle to draw the lines

 

[chuck5395]

I first cut out some blanks from a sheet of 1/4 birch plywood (40% off at Michaels).
I stacked these blanks together and used some panel nails to keep them together. Then it was off the the band-saw...


Once these were cut, I used my bench sander to finish the job. They turned out pretty nice for my first attempt.

 

[chuck5395]

First fin slot cut!

 

[patelldp]

Oh god! PLEASE use a wood backer on that drill press! NEVER drill into the table!

Any piece of scrap will do. Save your drill press, your bits, and your cutters!

 

[chuck5395]

Dan,
That is great advice and I sincerely appreciate it. I usually do use a wood backer. But this time I adjusted the press so that the blade would not reach the table. When I bottom out, I flip the piece over and finish it off. The cutter never touches the table.
-Chuck

 

[patelldp]

Okay...the thought of that fly cutter hitting that table made me cringe...

Ironically, I had been considering cloning one of these myself. Would you happen to have an accurate fin profile that you can share?

 

[chuck5395]

Okay...the thought of that fly cutter hitting that table made me cringe...

Ironically, I had been considering cloning one of these myself. Would you happen to have an accurate fin profile that you can share?

I hear ya on the cutter. I made that mistake awhile back. Never again.

As to the fin profile, I used the one that is a the RockSIM file that I downloaded from either LOC, RocketryPlanet, or RocketReviews (sorry, I don't remember which one). Anyway, when I compared the template that I printed out from OpenRocket to the fins in the old rocket, there is a slight difference. I went ahead with it anyway though. So to answer your question, No, I don't have an accurate fine profile....

 

[chuck5395]

All three fin slots are cut. I couldn't resist a dry fit quick look. I like what I see.

 

[chuck5395]

Next up was the attachment of a U-bolt to the forward centering ring. With a node to qquake2k, I took some scrap aluminum stock and made two backing plates for it.

I then put two brass inserts into the rear centering ring for motor retention.



Forward and mid centering rings epoxied in place. Also some epoxy slathered onto ubolt nuts and motor retention inserts.

 

[chuck5395]

Next I glued on two blocks to be used for rail-button attachment.

 

[neond7]

All three fin slots are cut. I couldn't resist a dry fit quick look. I like what I see.

View attachment 115705

Looks great! Is that the final nose cone you will be using? Its longer than the stock LOC-IV nose cone..... yeah, I know.... I'm being picky. ;-)

 

[chuck5395]

Looks great! Is that the final nose cone you will be using? Its longer than the stock LOC-IV nose cone..... yeah, I know.... I'm being picky. ;-)

Yes, you are right, that nose cone is longer than a stock LOC-IV nose cone. I just haven't been able to cost justify ordering one since I have this one available. But, I'll keep thinking about it since it looks like I'm going to need nose weight in this rocket.

 

[csoechtig]

Your build is looking very nice!

The LOC IV is a great rocket. It was my Cert 1 bird. Plus, I extended it for my first Dual Deploy recovery.



It is now retired. However, I did steal the fin design for this 3" scratch built...

 

[chuck5395]

Thanks Chris. Looking at your photos makes me think that Jeff is right. I need to order the right nosecone for this build.

 

[chuck5395]

While the guys south of me on I5 are out flying rockets, I can only work on them.
The month of May cannot come soon enough.

Time to attach the fins using my handy dandy Jim inspired fin alignment jig.







I had to use the work stand since the stove in my house is off limits. :wink:

 

[chuck5395]

Internal fillets are now complete.

 

[chuck5395]

More progress made this past week.

First, rear centering ring was epoxied in place.


Then the fillet lines were marked and tapped off.

 

[chuck5395]

Epoxy mixed and applied. Small piece of PVC used to shape the fillet.





Not bad, if I do say so myself. Once it firms up I'll remove the tape.

 

[chuck5395]

I recently purchased some 1010 rail buttons from Dog House Rocketry. Very nice BTW.

Holes drilled and buttons attached!

 

[chuck5395]

All the painting is complete on the body of the rocket. I am still in the process of acquiring a LOC nose cone to make it complete.
In the meantime, here is a photo of the rocket with it's top off.

 

[grouch]

That IV looks fantastic.

 

[chuck5395]

Thank you Mr. Grouch. All done with rattlecans and tape.
I'm actually pretty proud of it.

 

[chuck5395]

Finally flew this baby at NXRS on Saturday. My local on-site vendor forgot his box of new LOC stuff and so he did not have the LOC 4" nosecone that I wanted. I flew it with the Binder Thug nosecone that is in post #11 on a Loki H160-LB. It was great to see this baby fly. We then flew it again later that day with an AT-H178DM. Very impressive.