My Savannah S model rebuild Blog

[Kyle Communications]

Marty I have had several bed slingers and fixed or modified a few of my mates ones as well. Always some sort of dicking around with settings or whatever and changing filament can be a real PIA at times. Also the quality of the printing can be a little "rough" at times too depending on how well you tune your slicer software. My BIQU crapped itself a few months ago but I do have a RatRig Vcore3 here that I got about 12 months ago but havent had the time to put it together but I had been keeping an eye on what was out there. Core XY is really the way to go for a 3D printer as you dont have the momentum of the bed to worry about. Thats why I got the RatRig and with the accelerometer you can get rid of most of the ringing on your prints. Bambu Labs came out with a rush with the X1 Carbon but its the top end one but really the extra 800 bucks really isnt worth it. The screen is nice sure but the Lidar they use seems a bit hit and miss. I went with the middle one with the 4 rack AMS cost about $1600 bucks..hedged at the price but was seeing too many good things about it. It arrived a week after ordering...holy crap the easiest thing to get going ..the speed is unbeliveable and the quality is beyond anything I have ever seen in real life come off a 3D printer.

The engineers that founded Bambu are all ex DJI drone guys so you know the electronics and software is pretty slick..and it is. The automatic material system is just so good.No feeding filament anymore it does the intial loading automatically and changing when you select which one you want to print. I use the Bambu App on the computer and its connected to wifi and it just all works not to mention I can start a print and then go out the I can be anywhere and oen the app on my phone and look at the camera thats in there to make sure its all printing ok. To date touch wood I have not had one failure print. Everyone is just fantastic so much better than I am used to. Some examples I printed below

 

 

 

 

 

[Marty_d]

That certainly looks great Mark. 

I'm on a bit of a budget so had to limit myself.

The Ender 5 Plus was recommended as a good budget / starting printer by a colleague who has, like you, been into 3D printing for a long time.  $620 on special,  couple hundred less than normal. 

Those prints you've got are brilliant. 

[sfGnome]

How strong are the parts you make, Mark? Do they have a weakness along the joints between layers, or do the layers bond really well? I used a lot of prototype parts at my last company, but we always had to be really careful to not stress them. 

[Kyle Communications]

The Bambu Labs unit really prints the layers super accurately and they seem to bond exceptionally well. These ones are just PLA but I may print a set in ABS as the Bambu has a heated chamber and apparently does very well. I tested to breakage one the the PLA first ones at 15% infill and it was pretty good. At 60% infill its really strong..there isnt any stress on it where it is. The rivets will pull through the covers if the chute is deployed

 

[bobcharl]

Looking forward to seeing some more updates on Mable.

[Kyle Communications]

Hi Bob

Not a lot since the engine start and run. A few things like the parachute is now installed and those covers etc. I am subdividing the Burpengary property and its a huge job as all the 2 sheds there have to be demolished to suit the new alignment. My dads shed and my electronic shed have been cleaned out but the build shed 15 x 7.5 mtrsmit has to stay until the new shed 18 x 9 mtrs is put up on the new alignment. All the stuff in the 2 sheds has been packed into spare rooms in the house and the remaining big shed temporarily. To do this Mabel has been shifted down to the hangar to give me more room in the big shed. When I shift what I am keeping into the new shed like my CNC mill and lathe and a pletherer of other gear then the big shed will come down. This will allow the new driveway easement to be done. Its been a massive job but then there are trees to remove over the new property lines and fences to be removed..2 shipping containers to be sent to the farm...etc etc...so I am afraid no work on Mabel now for a couple of months. Also the spare time I have has been used making CDI ignitions and trying to get more htrottle kits done in a very temporary workbench setup in the big shed. My missus is up me as well she wants to go flying and we still have no flying aircraft. Mabel needs a few good solid weeks and she will be ready but I just cant manage the time but she has to be done as soon as I can get the time. Everything is down at the

hangar wings and tail feathers have been painted..fuse as well. Just need to paint the cowls

 

 

 

 

[bobcharl]

Busy doesn't even begin to describe your life.

All the best Mark.

[Kyle Communications]

Mabel is now back at Burpengary. I have purchased in partnership with a mate of mine a little fun machine that was too good to refuse for the price. It hopefully will be flown this weekend from where it lives at Coominya to YCAB so I needed to put it in the hangar. So Mabel is now back here in the new shed I have just had to put up here due to doing a subdivision on our block. So Mabel will be getting work done on it as my time has been very little to work on her since we started this massive subdivision here and other big jobs up at the farm.

I will get the tailfeathers on and all connected also get the seat bases back in and do some finalizing on the wiring. I will bring the wings back here too and get them fitted as the struts will be slightly longer as I will be putting a little dihedral on the wings and the new shed is big enough for me to be able to accurately do this.Will also need to look at getting the seats made as well. After a little cleanup work on the Genesis it will go up to the farm then Mabel will go to the hangar to have the wings fitted and final fitout.

 

[planedriver]

All looking good. The space you have would be the envy of many.

[Kyle Communications]

After a long hiatis I have finally been able to get back to work on Mabel. 20 months it has taken to get the subdivision done at our place and to be honest a lack of enthusiasm didnt help due to being too tired to do work on her at night after doing all the work around here we have done here. 

The parachute is now hooked up just have to finish off  some final running the main strap out of the hole at the top. The seat bases are back in and the foam has been made and ready for upholstery for them to be done. They will velcro then to the seats that are std for a savannah. The tail feathers are on and cables run and ready for hookup. Wiring for the elevator trim is done,static is run up to the top of the fin also. I will bring the wings back from the hangar shortly and fit them. I will be adding some dihedral to these wings this time. I have 4 new sections of strut material so I have to cut and fit them then I have a bit of painting to get done. There are some cover strips that have to be painted and once the new struts are done they will have to be painted. The roof section has been covered in IR and heat film and it has been fitted. The windscreen is all fitted but out at the moment while I am working on it. Then once it goes it the base section will be sealed with black sikaflex..a special one I managed to source. It would be nice to get her flying by the end of this year 🙂. Also got to trial fit the mrs and myself in there today..she likes the new comfy seats

[sfGnome]

Which parachute do you have? Junkers/Stratos or BRS? I’m looking for some dimensions of the Stratos 601 so I can put the mounting bars in the right spot but I don’t want to buy the unit until I’m almost ready to fly as I don’t want to wast half its lifespan sitting in my shed while I’m still building. 

[rodgerc]

Time to get her in the air Mark

[Kyle Communications]

20 hours ago, rodgerc said:

Time to get her in the air Mark

Working on it now I have more time 🙂

[Kyle Communications]

22 hours ago, sfGnome said:

Which parachute do you have? Junkers/Stratos or BRS? I’m looking for some dimensions of the Stratos 601 so I can put the mounting bars in the right spot but I don’t want to buy the unit until I’m almost ready to fly as I don’t want to wast half its lifespan sitting in my shed while I’m still building. 

I have a Galaxy GRS-600 they are all pretty much the same. I imported it myself direct from the factory. I hope to do the same with the chute that will go into the RANS S-21 but its a bigger chute and of course more expensive. The importing though is a whole new world of hurt but I found out after just by mistake how these parachute guys get them into the country with all the dangerous goods requirements.

 

Supposed to get them repacked and rocket change every 6 years . If you have a certified aircraft then you have to comply of course but as a private builder I have far more latitude. I have done a lot of reseach on longevity and most are all fine for at least 10 years or more. Some have even been 20 years old and when let off for sh$ts and giggles they all seem to work fine. Just always need to keep an eye on the straps and connections to the frame

 

Mark

 

[onetrack]

The propellant in rocket chutes should contain Guanidinium nitrate, which is the same propellant as used in airbags in cars. I've never seen a recommendation to change out airbags in cars, they're supposed to still work after 30 years or more. There are still many questions around old airbags in use, because older airbags used sodium azide, which is as toxic as cyanide.

 

Takata stopped using sodium azide in airbags due to toxicity concerns, and started using ammonium nitrate, which was deemed safer.

But the problem that occurred with the ammonium nitrate in the defective Takata airbags, was that if it got wet (and it was supposed to be sealed, but sometimes the sealing failed), then the AN developed little tunnels through it, known as "Ostwald ripening".

High temperatures made the problem worse, and effectively caused the AN to detonate when initiated, rather than burn (there's a fine line between the two, as you all know with fuel detonation).

 

As a result, all airbag and ballistic chute manufacturers now use Guanidinium nitrate, which is a long-standing and safer propellant. This doesn't mean this product can be mishandled, it is still a toxic compound and needs to be handled accordingly, especially when disposing of product which has reached the end of its lifespan.

 

All propellant in airbags and ballistic chutes should be detonated on disposal, to change the chemicals into less harmful compounds.

 

Edited 5 hours ago by onetrack
clarification...