Lakeroadster's F-79 Lone Wolf

[BBowmaster]

The view from the back reminds me of some destroyer-type star ship from the 1977 to 2019 era.

It’s the wedge-shaped wings that do it. I love the look from any angle. Wish I had the skills to duplicate it.

 

[lakeroadster]

It’s the wedge-shaped wings that do it. I love the look from any angle. Wish I had the skills to duplicate it.

Thanks.

I'll post up the complete drawing set once I launch it and prove the stability and feasibility of the recovery side pod configuration.

 

[lakeroadster]

Built the cockpit today. Laminated 4 pieces of 1/8" balsa, then sanded it to shape using my benchtop sander and some hand sanding.

I've also been building up fillets and closing gaps using a combination of Gorilla Wood Glue followed by Titebond Quick and Thick. It's a slow process, but thus far everything is ship shape.

 

[LW Bercini]

It's a pig... I agree, but that's ok. It will either blow, or go, either way, it will be a spectacular flying pig.

I love this sentiment

Do it because you love it. Nothing to prove. Nothing to defend.

 

[lakeroadster]

Full Disclosure... I mean if it was easy... everybody would do it, right?

I only had one piece of Ash hardwood left, just enough for two BT-60 size nose cones... or so I thought.

This is a piece of wood we cut from a sawmill my folks owned back in the early to mid 1970's... the only piece of wood I have left from my days as a logger / sawyer.

We cut down the trees, hauled them home, cut them into lumber and stacked the wood for drying. It doesn't get much more "Scratch Build" than that.

In true "only a rocket / space junky" would think this was cool.... I learned that this piece of wood is filled with worm holes. I stopped turning the first nose cone about midway through turning it, but may be able to salvage it for a future BT-50 based rocket.

The second one was better than the first, but not great by any means. The worm holes made it pretty much impossible to get a nice finish. The wood is hard in spots and pithy in others. That leads to a really rough surface as you can see below.

I may end up bailing on it... but it deserves to fly.... it's been waiting 59 years to strut it's stuff.

I'll add some filler and sand it, rinse and repeat until hopefully it is presentable.

The scallops are the business end of the M61 Vulcan cannons.

Wish me luck...

 

[neil_w]

Filler should be able to clean that all right up. Might take a couple of applications....

 

[BBowmaster]

That kind of history precludes any talk of giving up. Insert any number of Jethro Gibbs (NCIS show) aphorisms here.

 

[Blast it Tom!]

Full Disclosure... I mean if it was easy... everybody would do it, right?

I only had one piece of Ash hardwood left, just enough for two BT-60 size nose cones... or so I thought.

This is a piece of wood we cut from a sawmill my folks owned back in the early to mid 1970's... the only piece of wood I have left from my days as a logger / sawyer.

We cut down the trees, hauled them home, cut them into lumber and stacked the wood for drying. It doesn't get much more "Scratch Build" than that.
... ...
Wish me luck...

That I do! I have a dead ash up on the hill I have to take down, a victim of the Emerald Ash Borer that came though here. And I have quite a bit of cherry that I sawed about 12 years ago that I keep trying to get into a shed I keep trying to build... The heaviest sections are still outside under tarps on sticks. Now you've given me inspiration! Western PA cherry finishes really pretty but it burns easily when cutting & sanding.

That's a good looking rocket you're building there.

 

[lakeroadster]

After 2 applications of wood filler ye ole nose cone came out pretty good.

I need to let the filler dry a few days. In the meantime:

• install the side pod fillers,
• install the center baffle,
• bore out the back centering ring for the parachute screw eye and it's reinforcing ring,
• and glue on the launch lugs.

Then it'll be primer time.

 

[les]

Like the "Nose Landing Gear" used for the picture...
And the build has been fantastic!

 

[lakeroadster]

Like the "Nose Landing Gear" used for the picture...
And the build has been fantastic!

Les is more !

Thanks for the comment.

 

[lakeroadster]

Started gluing the side pod closures. The closures are made from 1/8" thick basswood. These each closure will see restrain 1/2 of the ejection charge pressure wave.

I was able to pour glue into each pod, install the closure then tip up the rocket to get a nice internal fillet. I also beveled the edges of the closures to try to get more glue contact area.

As we've discussed previously I'm a glueaholic.

 

[neil_w]

I love your various rocket holders.

 

[lakeroadster]

I love your various rocket holders.

The "Circle of Friends" is so handy. It allows optimal angles to place glue fillets "into position".

 

[lakeroadster]

Worked on launch lugs today. I relocated them so they are in the area of the rockets c/g. I originally had them glued up against the ventral fins which was at the bottom of the rocket.

Hoping to minimize the tendency of the rocket to get hung up on the launch rod in the event one of the cluster motors doesn't fire.

 

[BABAR]

Full Disclosure... I mean if it was easy... everybody would do it, right?

I only had one piece of Ash hardwood left, just enough for two BT-60 size nose cones... or so I thought.

This is a piece of wood we cut from a sawmill my folks owned back in the early to mid 1970's... the only piece of wood I have left from my days as a logger / sawyer.

We cut down the trees, hauled them home, cut them into lumber and stacked the wood for drying. It doesn't get much more "Scratch Build" than that.

In true "only a rocket / space junky" would think this was cool.... I learned that this piece of wood is filled with worm holes. I stopped turning the first nose cone about midway through turning it, but may be able to salvage it for a future BT-50 based rocket.

The second one was better than the first, but not great by any means. The worm holes made it pretty much impossible to get a nice finish. The wood is hard in spots and pithy in others. That leads to a really rough surface as you can see below.

I may end up bailing on it... but it deserves to fly.... it's been waiting 59 years to strut it's stuff.

I'll add some filler and sand it, rinse and repeat until hopefully it is presentable.

The scallops are the business end of the M61 Vulcan cannons.

Wish me luck...

View attachment 415317

View attachment 415319

Well crud, if you’ve already got the Wormholes, sounds perfect for a Star Trek Deep Space 9 rocket model!

 

[Daddyisabar]

Has a bit of a Sukoi look to it. You could put some external loads on it or even go gear down.

 

[lakeroadster]

Built the recovery eye attachment hardware and glued the insert into the rear bulkhead.

Cut the hole in the bulkhead using a 3/4" forstner bit. Super clean cut and no catches while boring!

The insert is home made basswood plywood, using (5) pieces of 1/16". I used loctite to insure the inner nut won't back off.

To glue the insert in place poured a decent amount of Gorilla Wood Glue into the rear opening / motor mount, ran some glue around the bore then placed the insert into the bulkhead opening. Then I stood the rocket up so the glue would run down and around the insert. I made another centering ring that will get glued over the rear bulkhead / insert sub. ass'y once the insert glue dries inside the motor mount.

Yeah I know.. it's overkill. But with the rear eject dual chutes in the pods if they pop out during thrust (think Evel Knievel's Sky Cycle jump over the snake river) the shock could be pretty dramatic. If I had thought about this design early on it would have been an easy "drill a 3/16" diameter hole in the rear bulkhead" affair.

 

[lakeroadster]

Has a bit of a Sukoi look to it. You could put some external loads on it or even go gear down.

I always learn something from your posts... I had to google "Sukoi"... way cool. The way the cockpit is positioned some of them look like they are bent... interesting design.

I'm wondering if their next model will be the "SU-Collusion"?

 

[Daddyisabar]

I always learn something from your posts... I had to google "Sukoi"... way cool. The way the cockpit is positioned some of them look like they are bent... interesting design.

I'm wondering if their next model will be the "SU-Collusion"?

One of the coolest paint schemes!

 

[lakeroadster]

One of the coolest paint schemes!

Leopard Shark... ish

 

[lakeroadster]

Glued the reinforcing ring to the recovery eye sub-assy.

Tricky part was finding away to apply some pressure to ring. Craftsman 3/4" socket... some rubber bands a 12" steel scale to the rescue.

 

[lakeroadster]

Here's the recovery eyelet reinforcing ring and also the reinforcing tubes added to the (4) nozzles.

 

[lakeroadster]

Worked on the internal baffle today. The idea is to split the ejection force pressure wave to help ensure each parachute deploys from each side pod.

Installed an aluminum deflector on the nose of the baffle, then slathered Gorilla Wood glue on the baffle to give it some protection from the hot gasses and the burning ejection bits.

I'm still a bit worried about the ejection charge burning the rocket up.... but based on feedback I'm getting in regard to baffles, this design really isn't any different in that the hot "bits" are trapped in those also.

I'll either gain confidence during the bench test..... or have a wienie roast.

 

[lakeroadster]

Bench test fired the rocket today on a single D12-5 motor to verify the recovery system works.

There were 3 things I wanted to verify using this test:

1. Strength of the recovery eyebolt attachment that will secure the parachutes,
2. Strength of the retaining method for the nose cone (3 wood screws),
3. Will the parachutes that are stowed in the side pods both deploy?

I built a fixture that secures the rocket to the stand via the recovery eyebolt.

The board with the hole in it that surrounds the nose cone is just there in the event the eyebolt attachment fails. The hole is smaller than the o.d. of the nose cone.

The bungee chord over the top of the rocket is not cinched down tight to the rocket, it also is just there in the event the recovery eyebolt attachment fails.

I used some dog barf ahead of the chutes but the chutes still got scorched. I'm thinking a small piston might work best that would fit ahead of the chute? I'm open for suggestions.

 

[neil_w]

The parachutes shot out of there so fast I had to set it to half-speed to see it...

I would think sufficient dog barf would protect the chutes. Was the dog barf definitely behind all the vent holes on the side?

 

[lakeroadster]

The parachutes shot out of there so fast I had to set it to half-speed to see it...

I sure as heck didn't see them at all when watching the actual firing.

It's been about 15 years since I last ignited a rocket, and I've never done a bench test. I was shocked at how loud the D12-5 was.

I would think sufficient dog barf would protect the chutes. Was the dog barf definitely behind all the vent holes on the side?

I believe the chutes were indeed below the port holes.... but.... I need to buy some better dog barf. I used some blown in insulation, salvaged from our attic, circa 1978. It's basically like powder.

I'm thinking it might also be a good idea to stuff the entire area above the chutes in the side pods with dog barf? Or maybe roll up some crepe paper to act as a piston?

 

[boatgeek]

I sure as heck didn't see them at all when watching the actual firing.

It's been about 15 years since I last ignited a rocket, and I've never done a bench test. I was shocked at how loud the D12-5 was.



I believe the chutes were indeed below the port holes.... but.... I need to buy some better dog barf. I used some blown in insulation, salvaged from our attic, circa 1978. It's basically like powder.

I'm thinking it might also be a good idea to stuff the entire area above the chutes in the side pods with dog barf? Or maybe roll up some crepe paper to act as a piston?

I think a technique I’ve seen here but haven’t used might help. If you put the dog barf in a cup of regular wadding, it will hold it together a bit better and be more like a piston. Getting a real bale of barf will also help. I usually use about one body tube diameter of barf to protect chutes. That seems to work well.

 

[neil_w]

I believe the chutes were indeed below the port holes.... but.... I need to buy some better dog barf. I used some blown in insulation, salvaged from our attic, circa 1978. It's basically like powder.

That sounds like it might have been the problem. Fresh dog barf (that sounds lovely) is not like powder.

I'm thinking it might also be a good idea to stuff the entire area above the chutes in the side pods with dog barf? Or maybe roll up some crepe paper to act as a piston?

Paper wadding should work as well, and I am keen to try out the technique that boatgeek mentions above (barf inside wadding).

Either way, I think your ejection scheme should work fine, just provide "sufficient" wadding of whatever type.

 

[kuririn]

Congratulations on a successful validation of a well thought out design.
Now when are we going to see it fly?