BLUE BRUISER BUILD

Don't forget to plug your sponsors



Maybe you could print out a small sticker

Coming along nicely Jeff. I have been thinking of building something for some low n slow flights and I think you have made my decision for me. I see a big ol LOC kit in my future.

bill2654 said:

Coming along nicely Jeff. I have been thinking of building something for some low n slow flights and I think you have made my decision for me. I see a big ol LOC kit in my future.

Click to expand...

Thanks Bill. I've always been partial to the 7.5" LOC kits - I've built them all!! Great for putting on a good show for the crowd.

neond7 said:

2. One LOC Angel "large" and one LOC Angel "Drogue" parachutes. Mark from LOC Precision will make them in red and black colors to match the final rocket colors. His parachute build quality is A+, most of my rockets fly chutes he made.

Click to expand...

I made them this morning and they are shipping to you today.
Thank you!

fox_racing_guy said:

I made them this morning and they are shipping to you today.
Thank you!

Click to expand...

As always, Mark - you rock!!

The 75mm Aeropack and parachutes arrived today from LOC. I decided to try using the Aeropack inserts as I had another centering ring available in case I goofed it up.
I mounted the centering ring on the motor mount tube, slid on the flange, and put a 75mm motor in it to maintain alignment. Then I used a small drill bit to start the holes, removed the flange and used the bigger drill bit to finish sizing the holes.
Using a hex wrench, I screwed in the inserts and then reinstalled the flange and to my amazement, everything lined up perfectly!!





I had also ordered a sheet of G10 plate, I'll use the wood avionics sled Always Ready Rocketry supplied to trace out the correct size on the G10 and then cut out a new sled. The wood would work just fine, but the black G10 is much sexier!!

Made a little progress today. Got the G10 sled cut out and the rails epoxied on after roughing up the fiberglass with an exacto knife for better adhesion. Also added the u-bolts to the bulkheads.







I also epoxied on the switch band.

Today I cut some wood blocks and added brass inserts to use as internal attachments for the rail buttons.









Not shown was all the epoxy I used to make the attachment very permanent.

This morning I epoxied the motor mount tube into the rear centering ring.







Because the fins don't contact the motor tube, I could add a huge rear fillet.

When this epoxy cures, I'll add a thick epoxy bead to the inside rear of the body tube and slide this in until it contacts the rear fin keepers. Then I'll reach into the front of the body tube and add another thick bead and slide the front centering ring in. Then I'll add fillets to both rings.

Oh, and here are the rail guide backing and rear of the fin lock tabs with a healthy coating of epoxy.

Both centering rings are now installed and filleted.







Seemed to take a TON of epoxy - I was mixing the West Systems slow epoxy with colloidal silica and high density filler to create a thick, no-run mixture.

Next step is to bevel the front of the fins (forgot to do that before installation) and then tip to tip glass.

At this rate, I'm anticipating first flight in November on an Aerotech 75/5120 L900DM.

Fins are now beveled. Nice sharp edge.

.

Next up was taping off for the fin fillets using the marks i previously applied.







I used West slow epoxy, mixed with colloidal silica. I was running low of high density filler so I used some high density filler mixed with low density filler, which gave it a red appearance.

Really nice looking fillets. Looks like you have your mix, timing, and technique down perfectly. I'm used to seeing fillets as good as that only with 4500.

Jeff, had any experience making pie crust? Ref. pic#3 post 39. Your fillet reminds me of a pie crust.

Had a great launch day yesterday! Today I continued on with the construction. Time for tip to tip fiberglass.

As always, I trace out a template to use.



Then I transfer it to the fiberglass.



I didn't get pics of all the steps, here was me getting the 6oz glass in place. Not shown was the 3 oz that went on top of it.



After applying the epoxy, I added the Teflon release film on top.



I did have some trouble getting it to follow the contour of the fillets.

After 2.5 hours, I removed the Teflon.



After that I trimmed the overhang.



I'll definitely need some touch up on the right side fillet, but nothing that can't be easy corrected.

Fiberglass complete on the 2nd set of fins. One more to go!

Jeff,

Nice build thread... Did you apply only one layer of 6oz and one 3oz FG and did you put any weights on top of the release film while it cured?

Spicer007 said:

Jeff,

Nice build thread... Did you apply only one layer of 6oz and one 3oz FG and did you put any weights on top of the release film while it cured?

Click to expand...

Yes, just one layer of each. No weights were used, the porous Teflon release film sticks nicely when applied and I make a lot of passes over it with a dry brush and it weeps out a little bit of excess epoxy. I do make a few slits in the Teflon to release bubbles and where it won't lay down perfectly on some of the fillets - the 7.5" rockets have bigger curves I guess and the Teflon is very stiff. I never have those issues on my 5.5" builds.

I see you fly at TTRA and NEFAR - my two fields! Mostly NEFAR. Hope to have this one ready for the November launch up there.

Jeff,

Thanks for the information, looking forward to seeing your Blue Bruiser fly at Varn Ranch...

Best of luck,
Leo

Yeah!! Last set of fins glassed. Epoxy is currently curing while I'm inside cooling off, about a two hour wait until I can pull off the Teflon release film and trim the overhang.







If I get some free time this weekend I may be priming all three of the builds I'm working on.

Lots of sanding and Bondo.



And now in primer. Still lots of imperfections to address, probably at least three sanding and priming cycles ahead of me.

Last night I spent about two hours sanding and reapplying Bondo to two of the builds. Tonight will be more sanding and a second coat of primer. Most of the bigger flaws have been fixed, now the struggle to not be too OCD or it will never get painted....

neond7 said:

Last night I spent about two hours sanding and reapplying Bondo to two of the builds. Tonight will be more sanding and a second coat of primer. Most of the bigger flaws have been fixed, now the struggle to not be too OCD or it will never get painted....

View attachment 302461

Click to expand...

Man I did 4 rounds prime bondo, I'd say 3 is pretty good especially after glassing! Looking good so far!

Second round of Bondo, sanding, and then a second coat of Duplicolor high build primer.

I also painted the first coat of primer on the payload section.

neond7 said:

Oh... We do have *cough* five *cough* of the little felines. It was supposed to have stopped at four, but a little Maine coon snuck into the pride earlier this year and found a forever home.....

Click to expand...

Soo, you're a cat rancher....
Nice build thread.

This build has not been forgotten - it has had several more Bondo/sanding/primer cycles and it was time for paint. The weather is finally cooling down and making it easier to work in the garage.

Then upper section was painted black, wet sanded with 600 grit, and a second and final color coat applied. In a week I'll hand rub it with some buffing compound and wax it.



The fin section will be two colors, the fins black and the majority of the body tube white separated by a red vinyl band. I shot the first coat of white.





It's been crazy building three rockets at a time!

Your prep work has paid off. Those tubes look fantastic! As arduous as it is, prep is the determining factor of the end result quality.

The white cured enough it would hold up to being taped off so i could paint the fins black.



I verified the vinyl had plenty of room. Mark at Sticker Shock supplied the vinyl, as always.



Then it was time to mask and bag so the painting could begin.



Finished result was excellent.



Next weekend I'll wet sand and apply second and final white and black color coats, followed by a red vinyl band.

I realized I've been slacking on the avionics bays!

Using my handy dandy Binder Design fin marking guide, I marked off four equal spots on the switch band to drill the vent holes and two marks for the switches.



Drilling was uneventful. I do prefer drilling through blue tube vs cardboard tubes, it leaves a much cleaner hole.



Tomorrow I'll primer the switchband, this one will be white.

I also removed all the masking from the parts I painted yesterday. Starting to really come together.

And the switch bands are now primed. I'll sand and shoot a second coat of primer tomorrow.

This weekend I will wet sand and shoot first color coat.

Oh man.... almost forgot about the nose cones!

Ok, honestly this is one of my least favorite parts - installing nose cone shear pin shims.

So here we are with three freshly washed nose cones. I had measured out the brass shims already.



Next I marked the nose cone shoulder where the shims will go and cut out the shims.



Here is a shim about to get epoxied in.



First shim is now complete on all three cones.



I'm using thirty minute epoxy for this.