Dynasoar Rocketry RC Rocket glider kits

Very nice Tom! We had a local club launch to try out a new launch site, had perfect weather, brough each of my kits and flew them all, plus my upscaled X-15, got in 13 flights in about 4 hours

Frank

Here are some great flight shots from our club president Gary Goncher at our new flying site in Silverton Oregon...

And a few more

Here is a video from yesterday with my dynasoar stack, the lifting body X-20 kit and the SST flying as well, enjoy!

[video=youtube;q7vwKL34I3U]https://www.youtube.com/watch?v=q7vwKL34I3U&feature=youtu.be[/video]

Got a bit of bad news today. The sole supplier in the US for depron foam has informed us that the manufacturer in Europe has changed the process of manufacturing depron which leaves it slightly softer and curved. They are running at 100% capacity in making this stuff for flooring insulation and don't care about the hobby market. Many small rc airplane companies rely on the fact that this foam has just the right combination of hard surface, stiffness, light weight and flatness. For small parts it may be ok, but for profile planes curvature cannot always be tolerated or designed out with carbon fiber, especially in the wings. Given this, the US supplier is no longer going to carry it. So I have enough in stock for about 30-50 planes depending on what is ordered and then that will be it. I do not currently have a substitute, the most likely option is thinner and softer/more flexible and would require redesign of the kits to have the same strength. I don't want to sell a product I'm not personally happy with. So, if you have wanted one or more of my kits, then the time is now to order because once I'm out of the good foam that will be it. I'm still planning on carrying the E-6 and E-12 rocket motors and cases for the foreseeable future.

Frank

https://www.rcfoam.com/stpg.php?page_id=5225

So Frank, this lower cost substitute mentioned in the article you provided doesn't work for your designs?

https://www.rcfoam.com/depron-and-e...el-foam/value-xps-closed-cell-xps-p-1603.html

No, is softer and thinner, wont work the way my kits are designed and kitted.

Frank

QUOTE=dixontj93060;1594404]So Frank, this lower cost substitute mentioned in the article you provided doesn't work for your designs?

https://www.rcfoam.com/depron-and-e...el-foam/value-xps-closed-cell-xps-p-1603.html[/QUOTE]

I had heard rumors of the Depron problem and hate that it has come to pass in this way. Especially hate that it is putting Frank's kit business on the rocks.

Still might be possible to do some workarounds to get the new Depron or the Model Plane Foam to be more usable.

When I was using blue core fan fold foam for profile models, it was possible to heat it and flatten it out. Might be worth experimenting with the new stuff to see what can be done in that area.

Have you ever tried the Model Aero Foam in 6mm from RCFoam (also called gediplac foam)? It s a little softer and lighter, so might be about the same as the Model Plane Foam

The 6mm XPS model foam that RC Foam sells is rumored to be the same as Model Plane Foam.

If it is straight, it might still be usable with some judicious use of additional thin carbon strips here and there to regain some stiffness.

Frank, ever consider getting some of the gray 6mm Depron that is actually very dark gray, almost black, to do the X-15 and your other black craft from? I think it is still the good stuff.

burkefj said:

Here are some great flight shots from our club president Gary Goncher at our new flying site in Silverton Oregon...

Click to expand...

It was really great to see you flying!

burkefj said:

Got a bit of bad news today. The sole supplier in the US for depron foam has informed us that the manufacturer in Europe has changed the process of manufacturing depron which leaves it slightly softer and curved. They are running at 100% capacity in making this stuff for flooring insulation and don't care about the hobby market. Many small rc airplane companies rely on the fact that this foam has just the right combination of hard surface, stiffness, light weight and flatness. For small parts it may be ok, but for profile planes curvature cannot always be tolerated or designed out with carbon fiber, especially in the wings. Given this, the US supplier is no longer going to carry it. So I have enough in stock for about 30-50 planes depending on what is ordered and then that will be it. I do not currently have a substitute, the most likely option is thinner and softer/more flexible and would require redesign of the kits to have the same strength. I don't want to sell a product I'm not personally happy with. So, if you have wanted one or more of my kits, then the time is now to order because once I'm out of the good foam that will be it. I'm still planning on carrying the E-6 and E-12 rocket motors and cases for the foreseeable future.

Frank

https://www.rcfoam.com/stpg.php?page_id=5225

Click to expand...

Are you going to be at NXRS? I think I need to order a couple kits....

I'll be at nxrs and can bring kits if you pre order. Tom, I've tried the gray depron and hated it, it was soft and nicked really easily I wont use it.

Trying to add carbon to model plane foam will get too expensive, carbon rods cost a lot.

I will look at test flite foam board its thinner but may be stiff enough with the paper backing. I'll have to test it and see how it glues and how hinges hold up, and it isn't waterproof and you can't sand rounded edges due to the paper which gives the stiffness. They have a waterproof paper version but it is brown so you'd have to paint it. Point is it will be a lot of work making new templates and instructions and wont work for some of the kits that need lamination. I was able to do these kits so quickly because I've worked wth depron for years, had tested and flown many of them a lot. If the paper flite test foam will work I may be able to do one or two of the tube based delta designs and keep most everything the same and keep to the same weight, we'll see.

Frank

I think you could add some strips of 3x1mm carbon or some 3x.8mm carbon in a couple of strategic locations (possible additional wing spar, fuse stiffener, perhaps embedded in the wing LE), and make the new more flexible material work for another 3-5 bucks per model, at most.

I know it impacts the kit cost for you, but I did some analysis on the material costs. For me, when I buy 10 sheets of 6mm Depron, the cost is about 75 cents per sq. ft. The new MPF foam is 49 cents to 61 cents per sq.ft., depending on who you get it from. The lower foam cost could offset some or even a lot of the added carbon cost.

On my designs, I don't use carbon tube for spars. I have been using 6x1mm carbon strips. Easy to slice the foam and bond in the flat strip.

I used to use strips but like the round spars better for most things now. As you said, there is potential for adding more carbon at extra cost and time for me to make the kits, cut and insert spars etc. I'd also have to re-build/fly them all to ensure I won't have flutter, as you found out in your rapier. Since the material is thinner and not as consistent I'll have to re-make all my templates for parts that have slots/tabs. I'm not a big fan of having to add lots of carbon here and there and the cost is more than you think per kit, carbon is not cheap. I don't like the softness of the mpf either just seems like it won't hold up to road rash as well. I'm pretty bummed, was reading about lots of different foam boards and they all have issues of weight, delamination of the paper etc. I built one of the IntR/Ceptors out the mpf and it just seemed floppy...

tab28682 said:

I think you could add some strips of 3x1mm carbon or some 3x.8mm carbon in a couple of strategic locations (possible additional wing spar, fuse stiffener, perhaps embedded in the wing LE), and make the new more flexible material work for another 3-5 bucks per model, at most.

I know it impacts the kit cost for you, but I did some analysis on the material costs. For me, when I buy 10 sheets of 6mm Depron, the cost is about 75 cents per sq. ft. The new MPF foam is 49 cents to 61 cents per sq.ft., depending on who you get it from. The lower foam cost could offset some or even a lot of the added carbon cost.

On my designs, I don't use carbon tube for spars. I have been using 6x1mm carbon strips. Easy to slice the foam and bond in the flat strip.

Click to expand...

burkefj said:

I used to use strips but like the round spars better for most things now. As you said, there is potential for adding more carbon at extra cost and time for me to make the kits, cut and insert spars etc. I'd also have to re-build/fly them all to ensure I won't have flutter, as you found out in your rapier. Since the material is thinner and not as consistent I'll have to re-make all my templates for parts that have slots/tabs. I'm not a big fan of having to add lots of carbon here and there and the cost is more than you think per kit, carbon is not cheap. I don't like the softness of the mpf either just seems like it won't hold up to road rash as well. I'm pretty bummed, was reading about lots of different foam boards and they all have issues of weight, delamination of the paper etc. I built one of the IntR/Ceptors out the mpf and it just seemed floppy...

Click to expand...

Planning on getting a box of the MPF type foam from RC Foam and splitting it with a couple of guys. Will do some experimenting and see just how much carbon or other material it will take to make a previous design stiff enough to fly.

Edge dings in the new softer stuff could be helped with some taping or adding trim Monokote to the edges of the model. Or more of the 1/4" wide styrene strips like you already use.

I do realize that the situation really impacts your kits and I respect that. I still think that, with some modifications, scratch building foam profile models will still be highly doable.

There are some other options for adding the additional needed reinforcement besides carbon: 1/32" x 6mm plywood strips might be a solution. Will have to be cut, but not very expensive for scratch building.

Too bad no one seems to sell 1/4" strips of fiberglass sheet stock, starting about about .020 thick and going to about .125 thick...that would be handy.

Oh, for sure scratch building is still very do-able. It's just that the depron characteristics made it ideal and very easy to get a strong, light, simple structure.

tab28682 said:

Planning on getting a box of the MPF type foam from RC Foam and splitting it with a couple of guys. Will do some experimenting and see just how much carbon or other material it will take to make a previous design stiff enough to fly.

Edge dings in the new softer stuff could be helped with some taping or adding trim Monokote to the edges of the model. Or more of the 1/4" wide styrene strips like you already use.

I do realize that the situation really impacts your kits and I respect that. I still think that, with some modifications, scratch building foam profile models will still be highly doable.

There are some other options for adding the additional needed reinforcement besides carbon: 1/32" x 6mm plywood strips might be a solution. Will have to be cut, but not very expensive for scratch building.

Too bad no one seems to sell 1/4" strips of fiberglass sheet stock, starting about about .020 thick and going to about .125 thick...that would be handy.

Click to expand...

I haven't tried this myself but have occasionally thought about hot wire slicing HighLoad 40 or 60 into sheets for that kind of use. Once an appropriate cutting device is set up its easy to do. Though I don't know how suitable it would be for your designs. [till I have time to try it myself]


Richard

It would all depend on the stiffness and properties of the foam, being in a color isn't great since it requires painting. Unless they make it in white, I didn't see it.

Pink but not white.


Richard

Deleted

I've built some of the Flite Test designs using the Adams foam board you can get at Dollar Tree. I think some of your designs it might work for, others not so much. Depron looks better and holds up better overall.

Just ordered the Spyplane - your website is showing out of stock on the pusher motor adapter.

Frank brought me an Arc Light to NXRS today - I can't wait to start building! I will be asking Santa for RC controls this Christmas (if not sooner...)

Yeah, that was a mistake, still have 7

Frank

Zebedee said:

Just ordered the Spyplane - your website is showing out of stock on the pusher motor adapter.

Click to expand...

I've run out of bt-80 tubing for the X-15-3 Delta kit, but I re-worked it slightly to work with the 2" tubing and the interceptor nose cone, I think it still looks pretty good and flies great, calling it the Hypersonic:

https://www.dynasoarrocketry.com/hypersonic-instructions.html

I've also worked out a drop ship deal for the E-6 RC motor reloads, shipping is $4.50 for up to six 3-packs, these must ship separately and go usps ground. $4.50 for each additional six for shipping. There is a Rocket Motor tab and you can order from the web site.

As for kits I have a good stock of the Interceptor/tube based Arc-Light, SST and Hypersonic.

[video=youtube;cFjEFsY35xM]https://www.youtube.com/watch?v=cFjEFsY35xM[/video]

Here is a new kit, calling it the Pegasus. I had five flights today, all glide times were about a minute twenty, the first flight must have had pixie dust because it just would not come own, literally over two minutes and I started to get bored and do a couple of rolls to lose altitude....We only filmed the launch and the last half of the flight, it was a lot of fun.


[video=youtube;O4sde24Ql_U]https://www.youtube.com/watch?v=O4sde24Ql_U[/video]

Frank

Spent some time yesterday working out a way to make a kit of a tube based Interceptor that doesn't use too much foam. Came out just over 11 oz rtf and flies quite nicely. Kit is simple except you have to cut the wing slot/fit it yourself after gluing the tubes together, but it is pre-marked for you. Not hard, just take your time.

[video=youtube;Bvh1MhxdRrM]https://www.youtube.com/watch?v=Bvh1MhxdRrM&feature=youtu.be[/video]

Wow! Fantastic Interceptor Frank! Great job!

You are probably all bored with my Variations on a Theme of "Cosmic Interceptor" but I'm having fun. 38" long, 26" wingspan. 11 7/8 ounces rtf as it sits now.

Sort of XB-70 inspired, using the cosmic interceptor parts, will do the small windows on the cone like I did on the SST, and put some nasa/usaf markings on when they get here. I put the canards on the cone, which I slotted using some pre-molded lines already on the cone to make sure they were not canted, so they angle down slightly but I like the look. I'm calling it the "Valhalla" to keep with the nordic god theme and avoid any copyright issues


Flew it this morning, went really great, another nearly hands off boost and really nice glide. Just a tad of downtrim on boost was needed. I'm using a similar wing planform for the most part for these tube based kits which means CG, instructions assembly etc are almost all the same, just minor differences in the wingtips, vertical stabs, markings etc to get a different look but with very similar flight performance. Makes parts supply and templates needed to a minimum while still allowing some variations for folks.


I also figured out a way to use my electric motor adapter with these tube based models, the battery sits on the right side under the wing and helps to counter the torque of the motor and the wiring just runs along the side of the fuse to the esc, easily removable for rocket flight. It's not very visible in flight. CG was spot on about 1/4" ahead of the rocket boost CG. That way you dont need to cut a hatch in the body tube and weaken it any.


Frank

Here's a video from this last weekend up in Seattle, flew with the BEMRC club and got in a flight on each of my kits, and the bomarc prototype. Appreciate goes to Bernard Crawley for giving me lots of plugs during the launch, lots of interest and questions. We fly next to the pacific raceways in kent so there was some great background noise.

[video=youtube;KHI6Q8YlGYo]https://www.youtube.com/watch?v=KHI6Q8YlGYo[/video]

Here is a group shot of my rocket gliders at NARAM today.

Three from Franks kits: InteR/Ceptor, X-15 and Bomarc.
The rest from me: one free flight: the Mig-21. The rest are RC: A4b, Guillow's Shuttle, Black Horse spaceplane, SA-14, XF-108 Rapier, Douglas D-558-3 Skyflash and the XB-70, in the back and going home for repairs.

1:24pm local time at NARAM: flew the X-15, the Douglas Skyflash and the Bomarc today. All great flights. Having a good time here in Walnut Grove!