Carbon Laser Loc 313… Yup, Carbon

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I have been getting the majority of my composite fabrics from these guys for years:

https://www.cstsales.com/
I like that they have a good selection, quality products, and that they allow you to buy in small quantities or save some money if you are willing to buy a decent size roll.

For peel ply specifically, I have tried all their peel ply and release layer products:

https://www.cstsales.com/a-vacuum-supplies-peel-plies.html
They are all good and give you some different options. I like the more porous release layers when I am doing vacuum layups because you get a more even coverage of the epoxy, but they leave a relatively rough surface that will need to be smoothed out (or not, the slightly rough surface could be a cool intended finish). The less or non porous peel plies and release layers leave a smoother finish, but you need to be more careful in your layups in order to ensure the epoxy doesn't pool up anywhere. Obviously, Mylar gives you a glass smooth finish, but is more difficult to use without pooling.

Their breathers are a good deal as well:

https://www.cstsales.com/a-vacuum-supplies-breathers.html
And, as a bonus, they are an Insta-cure CA dealer. Their prices are pretty much the same as most other places, but I figure I always need CA, so usually when I order composites I throw in a bottle or two of CA to get it all in on the same shipping bill.
Great Beta… thanks
 
Pulled the peel ply and it looks good.

Two light coats of epoxy and she will be ready to sand.

Unfortunately it doesn’t look like the “Carbon Laser” will be ready for the July 9 NOVAAR launch. Really don’t want to rush the next few steps.

Oh well…
 
Now that the July 4th festivities are completely behind me, it’s back to the Carbon Laser

This time progresses = sanding

Goal for the weekend is to get the booster to a point where I can cut out the fin slots. She was in good shape so an initial dry sand with 320grit followed by a wet sand with 800grit got me 83% of the way there.
D692737B-0AC3-4C2B-9DE0-431C59981E8A.jpeg

Once it was cleaned off I used a foam brush to apply a VERY light coat of epoxy:
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Once cured it will get a light wet sand with 800grit then it’s time to cut the slots.

Looking to the future have the “shakedown” motor and “full send” chosen
000AEBE8-B523-421A-A3C0-44F78F734544.jpeg
 
Love it when a plan comes together and a goal is achieved.

Sanded to booster as planned then marked off the slots. A lot of care was give. To measure everything to ensure the slots aligned. Put on my respirator and glasses (I know I’m not wearing gloves or long sleeves…)

Then got out the ol’ dremel and got to cutting

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To my surprise this was by far the easiest part of the build to date. The wheel perfect tracked the slot as the carbon cut like butter against the epoxy soaked cardboard.

Cleaned up the booster and got the rest of the pieces together.
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Even better all the slots lined up with the rings:


D022990D-06BD-4D5F-8C13-8285195E2CFA.jpeg

Next step is tacking the fins in place then full fillets to lock everything together
 
Now that the July 4th festivities are completely behind me, it’s back to the Carbon Laser

This time progresses = sanding

Goal for the weekend is to get the booster to a point where I can cut out the fin slots. She was in good shape so an initial dry sand with 320grit followed by a wet sand with 800grit got me 83% of the way there.
View attachment 526809

Once it was cleaned off I used a foam brush to apply a VERY light coat of epoxy:
View attachment 526810

View attachment 526811

Once cured it will get a light wet sand with 800grit then it’s time to cut the slots.

Looking to the future have the “shakedown” motor and “full send” chosen
View attachment 526812
Man I’ve flown the k2050’s little sibling the h550 for my L-1 and it was so cool I can’t wait to see this thing fly on that amazing super thunder! Best of luck
 
after some meticulous dry fitting and alignment it was time to tack it all in place. Very happy with it!

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Now for internal fillets. Going to lock it all in place for those sledgehammer motors.
 
Scuffed the mating area on the fin and the motor mount tube (again) with 220 grit. Lightly scuffed, nothing crazy, then mixed some T88 and applied. Each fillet was shaped with my all time favorite rocket tool, the tightly controlled and scientifically calibrated tounge depressor

F8EBEF4C-3C85-4503-A3A3-0F0143B24F03.jpeg
 
Moving right along. Time to permanently mate the motor mount / fin assembly to the lower airframe to complete the booster.

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First measure the location of the forward centering ring to make sure I can hit it when I drill for the rail buttons.

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Then mix up some T88. Some goes in the syringe to aid in securing the middle centering ring and the rest gets applied with my custom tongue depressor rig (three taped together just so…)

Apply the epoxy and slide it all together

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Next is external fillets
 
Looking great! What an insane amount of work. I love it! Makes me question my own sanity and motives sometimes though. You cut your fin slots exactly how I do mine however I like to use some blue painters tape as a guide and protection... Usually. On my warlock I didn't and it's a large diameter airframe... One slot has a nice oopsie where the dremel chuck was hitting the frame and I didn't notice.
Ken
 
Looking great! What an insane amount of work. I love it! Makes me question my own sanity and motives sometimes though. You cut your fin slots exactly how I do mine however I like to use some blue painters tape as a guide and protection... Usually. On my warlock I didn't and it's a large diameter airframe... One slot has a nice oopsie where the dremel chuck was hitting the frame and I didn't notice.
Ken

thank you my friend

Going in I was actually more stressed about cutting the slots than any other part of this build.

Was very surprised when it turned out to be a total non issue.
 
Fillets…. Those who have followed my build threads in the past know my love/hate relationship with fillets.

Well this build takes it to another level as it’s really a one shot effort as I really will not have an opportunity to sand or shape them after and can’t go to my stash of spot putting to address any imperfections.

The process was the same as always, however paid extra attention to detail.

Started by masking then scuffing with 220

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Rocketpoxy with black dye

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Use the aforementioned favorite tool to shape then pull the tape
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Do what you can to ensure the angles match on the next set…
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Overall I’m happy. A solid 93 out of 100
 
Wet your gloved finger with alcohol and smooth the fillets around the fin leading edge. Do this while the epoxy is not set but firm enough to remove the tape. At about 30 minutes for rockeypoxy.

I also smooth the edge where the tape was. Typically there is a small 'ridge' where the epoxy meets the tape.
This then gives you perfect fillets that needs no sanding.
 
yea, hear ya on the alcohol and gloved finger. have done that a lot on other builds.

opted not too here as I was worried (perhaps didnt need to be) that the alcohol could negatively affect the cosmetics of the carbon/epoxy if it were to seep through the tape.
 
did some calculations.

a 3" LOC airframe weighs about .23oz per inch. yes, standard measurements here...

the payload totals 24" for 5.52oz.

per the LOC design there is a coupler that joins the two pieces that make up the payload. that weights 1.7oz.

add in .5oz of epoxy (guess there) and you have 7.72oz w/o carbon and clear. note that is 5 coats of clear. i like my stuff shiny...

the finished weight of the payload is 12.3, which means the carbon, epoxy, and cleat add up to 4.58oz.

estimate 6oz for the booster as it is longer, and maybe 1 additional ounce per fin as they arent that big and I was able to vacuum them to remove more resin, you end up with 13.58oz of additional weight.
 
Got the rail guides squared away. These are from Teddy at OBH and are very nice. I cut small bass wood standoffs to help minimize the chance the rail will scratch the airframe.

Each is secured into a centering ring and are quite solid

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Yup, shot the clear on the booster as well. Will share at the final reveal : - ))
 
Mmm. Looking delicious! What did you use for paint and clear and what were the specifics about what went wrong. I've been down this road before but it's been several years.
Ken
 
The purple is DupliColor Metal Cast shot over the recommended DupliColor silver "ground coat"

The ground coat has effectively no limits on re-coat times, however the purple required that coats are laid down within three hours or after 7 days. This was the issue.

How did I get into a position where this was and issue? well sit back and Ill tell you a story...

I was in the process of inspecting all of the pieces of the Carbon Laser. the nose cone was looking good, no clear yet, but the purple laid our great! the clear was complete on the booster and payload, and the switch band was also complete. the tail cone needed some work, but all was good enough to put together for the first time to get a real idea of what she would look like.

stack everything in the rocket area of our basement (really this is 1/2 of our unfinished storage area, the other half is a gym) and DAMN, she looks good. I pick her up to admire what a few months of work has turned into and BAM smack the nose cone tip into my pull up bar. *(!@&()^)!@&#&^$()^&()@#$&~!!!!!!!!!!

ok, ok, ok calm down. this is fixable. spray a little ground coat into a mixing cup and brush a little on. let that dry then to shoot some purple to wrap up this repair... yup, you know what happened next.

so sand it all off, re shoot the silver ground coat then spray the purple. ugh, got a few very small runs in it this time. will let it cure for the full week, then wet sand to see what its like.
 
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