Page 1 of 6

Scratch build a Trike

Posted: Sat Jan 30, 2010 1:11 pm
by ystervark7
I have just started on scratch building a trike. It will be build based on my own plans but a lot of the ideas will be based on existing designs, especially on Vliegvark's ideas. (No need to reinvent the wheel.)
The main features will be:
1) Use as much commonly available material and components
2) Frame will be stainless steel while most of the suspension and fuel tank will be aluminium
3) Wing will be bought - topless from Yenya
4) Engine a BMW 1200 - I will try to put a belt drive on rather than the gearbox which will be about R25000 cheaper.
5) MAW 450kg
6) -1 to +4g for maneuvers max -2 to +6g
7) > 80 l fuel tank
8 ) adjustable front seat
9) brakes - must still decide
10) trailing link front suspension
11) back suspension traditional trike design with shock absorbsion
12) cruise speed I aim for 105 km/h

If anybody is interested I will make the plans available.

Currently I am more or less finished with the drawings and I have just ordered the first laser cut parts.

Here is a drawing of the frame without the wing and engine.
Trike1.jpg
Trike design

Re: Scratch build a Trike

Posted: Sat Jan 30, 2010 8:30 pm
by charl
You forgot to mention the most important thing ... their will be no aileron tube in your face!

For my 2c, I think you will or must aim for cruise 105kph

Good luck!

Re: Scratch build a Trike

Posted: Sat Jan 30, 2010 11:22 pm
by mikeinPE
This looks like another interesting post that I'll have to follow closely. I'd love a set of plans when they are available Ystervark. Strongs with the planning!!!

Re: Scratch build a Trike

Posted: Sun Jan 31, 2010 5:08 pm
by Spatzi69
Fantastic Project! Looks almost like the DTA! About the brakes, I would go for two disk brakes on the rear with some lekka fat tires!
Will you be welding the frame together and what is the estimated weight going to be?

Re: Scratch build a Trike

Posted: Mon Feb 01, 2010 6:13 am
by Lieb Liebenberg
(^^) Good idea.Will follow closely and will pay for plans.I imported plans from Airtrike/Canada,but will wait for progress from you.Maybe I am just scared!BMW motor and reduction gearbox are for sale from Airtrike for ± Can $ 8000-00.Good luck,wait to hear from you! (-)

Re: Scratch build a Trike

Posted: Mon Feb 01, 2010 7:56 pm
by ystervark7
Well Charl, I sort of assumed that I do not have to mention that it does not have a profile tube in front. Is there ather way to build a trike? vhpy

Yes the main concept is based on the DTA Voyageur. The DTA uses a complicated boxed section pylon made from aluminum, rivets, a cables and glue as I understand it. This design is too complicated for my limited design skill. The rectangular tubes are much easier to design and build. We (vliegvark) have build one in the past already and we have tested it by hanging 3 tons from it which is about 6g. I am therefore reasonably confident that it will be strong enough.

The frame will be welded. The weight is always difficult to estimate and I think that you will always underestimate. I aim for less than 200kg. To give a bit of perspective on how much weight you are going to add using stainless steel:the frame will be made from 80x40x1.5 mm rectangular tubing which weigh 3.86kg/m. you need about 4 m for the pylon and frame which gives you about 15kg. You still have to add all the other stainless steel brackets and stuff which might be another 10kg. The total weight of all the stainless steel parts will therefore be about 25kg. The rest will be the same as a normal trike, so the final weigh will depend a lot on what you add anyway.

I am considering disk brakes. Would even like it more if I can buy them off the shelve. Yes I can make them but I have enough other things to make. Any suggestions where I can find small disk brakes that will fit on a 150mm brake disk? Scooters or quad-bikes are probably where I should start looking.

For those who are interested, the design will be available for a case of beers (^^) , but if you need the money for more trike parts, we can negotiate (may be one or 2 conditions attached).

The front fork detail is shown below. It uses a trailing link suspension using normal off the shelve Gabriel gaslifts available at most spares shops. (idea also borrowed from DTA) I have allowed for some alternative as well, you can either use 2 19mm ones with a 200 or 250mm stroke or a single 22mm 209mm. The 19mm ones allow a longer stroke (250mm) because the 22mm is not available in 250mm.


There is no reason why you can not use any other fork. The easiest might be to use a fork, wheel and brake from a old trike.

The 2 drawings show the 19mm x 250mm gaslifts at both extremes. This should give enough travel for the roughest terrain .
ForkShort.jpg
Full retracted fork
ForkExtended.jpg
Fully extended fork

Re: Scratch build a Trike

Posted: Mon Feb 01, 2010 8:26 pm
by mikeinPE
Just tell me what beer you prefer, so I can start saving!! :lol: This thread has my full attention.

Re: Scratch build a Trike

Posted: Tue Feb 02, 2010 12:02 am
by Oupa-G
One can see that Ystervark is doing things in detail, That is the sort of detail that went in to the Eboxi.

Cheers Oupa-G

Re: Scratch build a Trike

Posted: Tue Feb 02, 2010 7:49 am
by Tailspin
I will also keep a close Eye on this one.

Maybe a next project :?:

Re: Scratch build a Trike

Posted: Tue Feb 02, 2010 12:29 pm
by ben
Hi Ystervark

This is going to be a very interesting post/project. I will be following it very closely. The chance is very good that I will also make use of your offer regarding the plans. The hubbly bubblies will be delivered at your doorstep. I have a complete wing, Wind 2000 from Jenya, to kick off with. Less than 3o hrs. Again, I like the idea.

Ben
ZU-AJN

(^^) (^^) (^^) (^^) vhpy

Re: Scratch build a Trike

Posted: Wed Feb 03, 2010 9:33 pm
by ystervark7
Glad some people are interested in building a trike. I think trikes are a bit out of fashion at the moment but if you want to really fly, this is the only way to fly with the wind in your face and you feel the air movement as it plugs on the wing.

By making the plans available I hope to make trike flying just a bit more affordable for those who have the skills and inclination to build their own trike. I will also make a complete bill of material and keep track of cost for those who are interested.
My basic philosophy will be to use material and parts that are easy to find (world wide I hope) while still trying to keep the quality up to or close to aeronautical standards. I will also try to limit the skills and tools needed. A lot of the stuff will be TIG welded which might be a problem for some people but I am sure that you will find a skilled welder close to most major towns. A lot of parts will be laser or waterjet cut which is accurate and affordable.

Stainless steel 304 was chosen because of its oxidation resistance (I live close to the sea) and relative high tensile strength (about double mild steel). Unfortunately it is not so resistant to vibration. I will try and compensate for this by "over designing" it at critical areas where possible and building in some safe guards. An example is the pylon which is one of the critical areas. The pylon section will be welded airtight and fitted with a valve. It can then be pressurized, with nitrogen if you want to, and the pressure can be checked with the preflight. The smallest crack will therefore be detected early and can be fixed. The same can be done with the frame but I do not think it is necessary. The aluminium part will be mainly 60601-T6 which is easy to get and is reasonably resistant to metal fatigue as I understand.

If there is enough interested I will take the different parts of the design and place it on the forum for discussion each week.

I got my first parts recently vhpy - very exciting for the builder - much like a new tool. Most of the stainless steel is on order as well.
FirstParts.jpg
First parts: Laser cut parts for front fork
FirstParts.jpg (34.61 KiB) Viewed 12994 times

Re: Scratch build a Trike

Posted: Thu Feb 04, 2010 1:49 am
by Cloud Warrior
Hi Ystervark

I think this will be a very interesting thread.

My apologies for asking a lot of stupid questions but please be patient - I would really like to understand the thinking behind the design as you progress.

Do you intend to do any FE analysis on the design? Or just do a physical test of the airframe at the end?

Is there a engineering standard that you will reference for your design?

Will you be taking fatigue into account in the design?

How did you determine the position of the hangpoint?

Hope the build goes smoothly. If you run into any problems I work with some structural guys that could give advice if needed.

Cheers

Sebastian

Re: Scratch build a Trike

Posted: Thu Feb 04, 2010 6:18 am
by Lieb Liebenberg
(**) Cant wait (**) Cant wait (**) Cant wait ($$) ($$) (^^)

Re: Scratch build a Trike

Posted: Thu Feb 04, 2010 6:20 am
by Spatzi69
Then Hang point is quite simple to figure out! It is usally over the passenger seat for the reason that there is always a pilot and engine on either side so you balance those two to be exactly the same to make the CG very close or not far aft! The passenger will then be seated right on the CG and will not affect it at all!

Re: Scratch build a Trike

Posted: Thu Feb 04, 2010 7:25 am
by Boet
Yatervark, jy gaan n alcohaulic raak!! :lol: Hierdie gaan weer n mooie wees. :wink: