Biggest scratch build yet - Bluto

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Before I decide on whether or not to add outboards, I had to make sure I could even make the massive centering rings. I made a template, marked the center, drew a centerline, and drilled a 5/32" hole in it. I had made a simple circle cutting jig for the bandsaw, but quickly discovered a problem. Apparently the outside edge of my bandsaw table has a slight angle in it, which made the jig sit at an angle when I clamped it.

Looks like a shim between the edge of the table and the jig should take care of that easy enough.
 
I used some wood shims, and got the jig to sit fairly close to level. I'll have to fix it better once I figure out how to do it. I attached the piece of 3/8" plywood to the jig with a #8 sheetrock screw, and cut the circle. It worked great! Sure am glad I put that new blade on the bandsaw. I drilled out the center hole to 1/4" to mount it on the lathe.

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Some have a need for speed, some have a need for altitude. Well apparently, I have a need for girth! Bluto will be 7.675" diameter, 82" tall, and (according to Open Rocket) approximately 17lbs on the pad. He'll have a 54mm motor mount, and be set up for dual deploy, although I don't know yet if I'll fly him dual or single. That's my 6'3" 300lb son standing next to the components. He's gonna be a big one!

Hey Jim,what are you feeding that son of yours??????LOL.Fine looking lad,I'm sure he takes after his Father and is the same thoughtful and kind person.Give him my best for New Year.Man is that a great picture,shows the scale of the rocket.I like the Red Nose Cone and Black body tube combo as my first choice,but with the larger fins.
 
Once I got it on the lathe, I was able to trim the centering ring to final size just like I do smaller rings. Man, this thing is gonna be big!

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Looks like a shim between the edge of the table and the jig should take care of that easy enough.

Yeah, but the wood shims I used are a slightly shallower angle than it needed. I'll figure something out.
 
Got the circle cutting jig fixed. I took the "leg" off and sanded an angle in it with the disc sander. It wasn't quite enough, so I glued some shims to it.

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And with the jig, I cut out the other centering ring and the bulkhead. I also drilled the holes in the bulkhead for the big 5/16" u-bolt.

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I still haven't decided about the outboards, but I've been doing a lot of thinking about them. I'm still leaning towards a single 54mm motor mount. A K reload will take Bluto to around 2500ft. That's plenty high enough for Captain Low-N-Slow. And that would be $100 or more for one flight. If I added outboards, I could easily get up to $200 per flight, plus I'd have to buy more motor hardware. I don't know, I'm still thinking about it.
 
Obviously, if you don't put them in, you can never fly a cluster. Put 4x 29's or 4x 38's in there, make a few sleeves out of coupler tubing to protect them from getting scorched, and forget about them until you are ready to try clustering!
 
Jim..just an idea if you will be making your own rings from now on...maybe drill and tap two 1/4 20 holes and use two countersunk flat heads to keep the jig in place?
yea,I know drill the Bandsaw table...:bangpan::2:
 
Obviously, if you don't put them in, you can never fly a cluster. Put 4x 29's or 4x 38's in there, make a few sleeves out of coupler tubing to protect them from getting scorched, and forget about them until you are ready to try clustering!

Yeah, I've been thinking about that. If they're not there, I can't use them. But if I do add them and don't use them, I will have to figure a way to plug them.
 
Jim..just an idea if you will be making your own rings from now on...maybe drill and tap two 1/4 20 holes and use two countersunk flat heads to keep the jig in place?
yea,I know drill the Bandsaw table...:bangpan::2:

Great minds think alike! Although I wasn't thinking of drilling into my bandsaw table, I was thinking about using something like this in the miter slot. (Scroll down to the "Miter T-Track Accessory Kit".)

https://www.mlcswoodworking.com/shopsite_sc/store/html/smarthtml/pages/miter_t-slot_accessories.html
 
I got started on the slightly smaller av-bay bulkheads. Since the coupler is 15" long, and the Stiffy is 14" long, I decided to use 1/2" plywood.

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Somehow, I cut two bulkheads in a row too small for the av-bay. So I had to get another piece of 1/2" plywood from Michael's (thank goodness for the 40% off coupon!), and cut one more. Third time's the charm!

I held the two bulkeads together with a 1/4" bolt, while I drilled for the threaded rods. At first I marked them 1" in from the outside, but decided on 1-1/2" instead. I cut two 16" long pieces of 5/16" threaded rod. Like my cool new soft vice faces? I got them at Lowe's. They worked great!


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Cut the outboard holes! You don't have to plug them if the forward most centering ring does not have the holes. So long as you are making more than 2 centering rings, the two or more aft ones have the holes and the MM tubing. The forward most one only has the 54mm hole.

Just an idea. But hey... its your call! :wink:

Happy New Year!
 
Cut the outboard holes! You don't have to plug them if the forward most centering ring does not have the holes. So long as you are making more than 2 centering rings, the two or more aft ones have the holes and the MM tubing. The forward most one only has the 54mm hole.

Just an idea. But hey... its your call! :wink:

Happy New Year!



yes ^ what he said :D

motor mount.JPG
 
So I had to get another piece of 1/2" plywood from Michael's (thank goodness for the 40% off coupon!), and cut one more. Third time's the charm!

I can't imagine Michales is cheap when it comes to plywood even with a 40% coupon! You use enough plywood to be buying full sheets, should be cheaper that way.
 
I can't imagine Michales is cheap when it comes to plywood even with a 40% coupon! You use enough plywood to be buying full sheets, should be cheaper that way.

I've actually looked at full sheets of plywood, and bigger than the Michael's sheets at two specialty hardwood suppliers, and at Woodcraft. I've also looked at hardwood plywood at Lowe's and Home Depot. The problem is finding straight stock. The bigger sheets that I've looked at are always warped. The Michael's sheets are 12" x 24", and I can usually find really nice and straight pieces. The 1/2" sheet was $9 before the 40% coupon.
 
Because of the thickness of the 1/2" plywood and 1/8" aluminum backing plate, there weren't enough threads sticking through for the nylon lock nuts. So I got some thinner jam nuts for the u-bolts. Now there are *just* enough threads for the lock nuts.

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That is very clever. His bandsaw sure is quieter than mine!


But your bandsaw looks like it has a nicer fence system , I have Laguna tools band saws the fences on both are crap


nice blade you are using too , how may teeth and width ? 1/4" by 14 ?
 
But your bandsaw looks like it has a nicer fence system , I have Laguna tools band saws the fences on both are crap

nice blade you are using too , how may teeth and width ? 1/4" by 14 ?

I'm really happy with my bandsaw. It's a Craftsman, but I believe it was made by Rikon. The fence is nice, and it's adjustable for resawing. The blade I just got is 3/8" x 14 TPI. I've tried 1/4", 3/8", and 1/2" wide blades. I prefer 3/8" because for me it's a good mix of straight cuts and curves.

https://www.toolcenter.com/80539-NEB8-2535.html
 
I've been playing around with adding outboards in Open Rocket. One thing I hadn't considered, is stability. If I add say two 29mm H outboards, I'll have to increase the nose weight by at least 6 oz. That'll take the rocket to close to 20 lbs.
 
I've been playing around with adding outboards in Open Rocket. One thing I hadn't considered, is stability. If I add say two 29mm H outboards, I'll have to increase the nose weight by at least 6 oz. That'll take the rocket to close to 20 lbs.
A 98 and 8 38's will fit :wink: Business End Large.JPG
I put a 54mm motor tube in the nose cone. If weight is needed, a 54mm motor case full of dirt serves for nose weight. Just install it like a motor. I used a fiberglass nose cone, the centering rings bond well. A LOC nose cone will be more difficult.
 
A 98 and 8 38's will fit :wink: View attachment 110431
I put a 54mm motor tube in the nose cone. If weight is needed, a 54mm motor case full of dirt serves for nose weight. Just install it like a motor. I used a fiberglass nose cone, the centering rings bond well. A LOC nose cone will be more difficult.

That's crazy! Have you flown that thing with all nine motors?

Yeah, I've been trying to figure a way to do adjustable nose weight. I know epoxy won't stick to this nose cone worth a darn.
 


I've heard of people pinning the epoxied all-thread. Basically, you run wood dowels from side to side sticking out the nose cone. Slightly off center to allow the all-thread to be in the center. Once the epoxy cures. You saw off the pegs sticking out of the nose cone and sand smooth.

Another idea, and I am not sure how to do this, two wooden plates with rubber between them. As you tighten the plates together the rubber expands outwards to grip the insides of the nose cone.

Another idea... put two eyebolts on either side of the base of the nose all-thread down the middle. Use the two eyebolts and a metal strap (with three holes, two for the eyebolts and one for the all-thread and use nuts ont either side of the all-thread to keep it in and the eyebolts to keep the metal strap on. Probably need to reinforce the back of the eyebolts with fender washers... that can be tricky...

Another idea. Cut off the base of the nose cone and use some 1/4 or 1/2 inch ply and literally screw together the bulkhead to the nose cone shoulder with countersunk screws.

 
That's crazy!
It may be crazy, but he will not have to build another rocket to try 2, 4, or 8 groundstarts. :wink: And 2, 4, or 8 airstarts.

OTOH you love building so much, maybe you should wait! Clustering is a great reason to build another rocket. Parallel staging... another rocket... Two stage composite... another rocket...
:lol:
:wink:
 
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