G'day all,

For weeks I've been wanting to make a sp400 pylon racer, something cheap and simple so that a half dozen or so club members could have a bit of -fun- (please remember this, it's not about outright speed) racing.

I drew up lots of plans but couldn't settle on the wing, I even looked at some RCM&E plans for things like the Limit-EX. Finally I got kicked into action after seeing Sargentspark's Almost-Sokol and his solid wing, however I got a little carried away on his thread and have thus decided to start my own thread to save confusion.

The Slipso is based on the following ideas

- Cheap
- Quick build
- Common materials as much as possible
- FREE plans

The plan is available below.

There's also a single movie of the plane in action (the plane in the video is currently deceased due to excessive velocity and negative attack angle to the ground while my thumb was asleep at the job of the elevator).

UPDATE: 2006-May-13: New video in flash format

http://www.pldaniels.com/flying/vide...ideo=slipso400

The wing is covered using brownpaper+PVA(white) glue and then covered with laminating film (makes good live hinges!)

Nice work. Plans downloaded

Hey, a fellow Aussie

I should point out that the plans aren't as yet 100% perfect, that's something which I've found takes a lot of revisions (my other designs still get periodic revisions). Anyhow, any competent builder should still be able to hack their way if there's something missing.

I also forgot to mention the other vital stats about the plane

Motor: GWS 380/400 6V motor
Battery: 8 x AAA 830mA with deans connectors
Controller: GWS ICS-480
Receiver: GWS R6NII
Prop: APC 5.1x4.5
Spinner: MPJets 30mm aluminium
AUW: 350~400g

I really need to improve the battery pack as it barely gets 4 minutes of life. I'm sticking with NiMH's because they're relatively cheap to the 3s lipos ($20 vs $50~60).

Paul.

Yup

Plans are a guide only. I am sure I can work it out.... and most likely come up with my own little ideas here and there (I won't be able to help myself )

I'd try either a pack of Kan1050's, GP1100's or IB1200's for improved performance and flight time.

The standard for speed400 racing is 7cells, most using GP1100's. Also look at the 4.75x4.75 for more speed.

Shawn

Shawn,

No problems what so ever with you modifying things to suit your own needs. A lot of "design descisions" are based on what one feels most comfortable with in terms of build techniques and available materials.

I'll try get some KAN1050's - not sure about only 7 cell, won't that be a bit 'weak' on a 6V motor? What motor do you normally use? I'm using GWS 380/400 motors which are definately "hotter" than the Graupner 7.2V motors.

... eager to know more

Paul.

Oh, where do you recommend getting your packs/cells from?

Paul.

Current state of affairs -

Okay, it's 01H45 here, time for me to head off to bed.

Managed to get the triangular stock into the framework... why I don't do this _before_ I assemble the sides together I will never know.

Paul.

Got the tailplane done and started sheeting the top/bottom decking of the fus. Elevator servo is installed and the pushrod/wire guide.

Stuntman / Shaun,

So, what mods are you going to do? I've already done a couple myself, as I said, a never ending process of adjustments.

Even though I've not even finished this one yet, the next one I'm going to use a 3 x 3.2mm laminate for the wing so that I can get some real airfoil section into it and help cut the drag down through the turns (plate-like airfoils are horrible for moves like that). I've also already changed the orientation of the elevator servo so that I can put the tristock all the way up to F3, letting me get some more curving in.

Paul.

Ummmm, not sure I haven't got past printing out the plans yet . Few other things on the go at the moment, but I'll get to it.

Probably carve the wing and also add some carbon tow to the bottom of the wing. Maybe also put some thicker sides on so I can carve a more rounded shape.

I use either the 6V graupners or the 6V ACW ones. Using either 5x5 or 4.75x4.75 APC prop. 8cells would be better as with 7cells a good launch is required. Once on step though they work well enough on 7cells.

I usually get my cells from www.cheapbatterypacks.com

I am not sure what I've got at home, l'll have a look and if I have some I'll send some up (I usually buy 50 -100 cells at a go !! and supply the club guys as well - but I am running low as most have switched to LiPo now)

cheers, Shawn

New class for 400 pylon allows the use of brushless motor and either 100grams of LiPo or 180grams of NiMh/NiCd. So either 3S 1320's/1500's or 8GP1100's. Turn graupner 3x3 prop at 40,000+rpm on 3S with an axi 1215/12 but this gets out of hand too easily and its one prop per flight so its not fun - but it is fast ;D

Originally Posted by Stuntman

Probably carve the wing and also add some carbon tow to the bottom of the wing. Maybe also put some thicker sides on so I can carve a more rounded shape.

Well, there's CF tow on the bottom of this wing that I'm doing now - it's even mentioned on the plans

As for the sides being "thicker", I tend to use 3.2mm balsa and 6mm triangular stock so I managed to get some level of "roundness" - amazing what 20 minutes with the razor plane can do.

prop. 8cells would be better as with 7cells a good launch is required. Once on step though they work well enough on 7cells.

Well, I'm going into the 'big city' *cough cough* tommorow so I'm going to see if I can get 20 or so cells, enough to make up a couple of packs at least.

... I tried phoning the place but they never called back *GRRR*. Shame that Cheapbatterypacks are non-Australian.

Paul.

Make sure you get 24. Otherwise you will have 4 left (ok for an RX pack). I make this mistake every time......

Yeah I like to use triangular stock and would probably go to a soft light 1/4 sheet. Then you can really get into it with the plane (something about plane shavings, be it balsa, pine or whatever thats theraputic). Anyway then I would probably lightly dope the fuse and maybe even dope and light tissue or dope and 3/4oz glass on top to toughen it up.

Good luck in the big city

Shawn

You shouldn'y worry about Cheapbatterpack being an OS trader. They're good to deal with and their prices are much better than what I've seen in Oz. I think they discontinued the Kan cells though. A better buy is the CBP 1150's anyway. Cheaper and will hold a voltage better. Aircraft world have Kans a a slightly higher cost if you don't have any luck sourcing them locally.

Nice plane too.