1/6 Slingsby T21 - Jilles Smits

[Wayne]

Metalwork:
Main wing Fixings
Acquiring the correct metal sections can be difficult but I find that if I shop around (Wwebb search) eventually I come across what I need, I found 2 sections of alluminium on Amazon for aprox £10 and yes sounds expensive but you get a either 1metre or 500mm length which will get used up somewhere along the builds.

Once the brackets have been cut, again check against the formers and ribs for accuracy befor drilling holes even though I found the drawings accurate I find it best to do it this way to ensure no issues later when assembling.

[Wayne]

Main wing assembly:

Lay out and dry assemble wing ribs along W1 plywood Webb former, yes I have plywood on order so the fusealarge will be completed later but fir now has been set aside so to maximise build time.
Note: I'm not using wing servos for the air brakes however in hindsight I would recommend using them as I later purchased some for the aelerons and the fit perfect, if you use standard type servos as i have youll need to purchase a servo reverse unit to make this setup work as both servos will actuate in the same direction.
Hers the link for the wing servos cost £30.20 for 2 and they come with a variety of control arms.
Corona Digital DS239MG Thin Metal Wing Servo Metal 4.6kg / 0.15sec / 22g Remote Comtrol Glider Digital Servo https://amzn.eu/d/aiAIP64

Note the 2 scap pieces of 1/4 x 1/4 spuce used the assemble the airbrake servo trays, these are not glued but removed when the Servo tray assembly is dry, this ensures a good fit when the top and bottom spars are installed.

[Jilles]

If you have a more modern transmitter a servo reverser is a thing of the past
With an 8 channel TX you can assign each control surface with its own channel including tow release.
I find it very handy to adjust each control surface on its own. For ailerons it is easy to set the up & down travels like the down travel set to only 50% of the up travel . It can be done by mechanical means but is very complcated to get that right. The reason to do this could be subject for an other forum story for those that are not familiar with this

[Wayne]

Thanks fir the information Jill's

I have a 7 channel futaba with mixing and looked at this option however the mix is not linnier maybe I need to update my transmitter, hey ho, the reverse devise works fine adds no noticeable weight and cost was £4.99.
I did use 2 old servos but now one has got a glitch so I'll likely change them for the specified wing servos.

[Wayne]

Having checked the wing joiners and the incident pin align up before epoxing, they were epoxied in situ. I'm using carbon rod and tube.
Now the tedious bit, but taking my time so to get nice finish.

oooOOOPS, one of the aileron ribs broke off but that'll be reattached.

Update:
I assume no one noticed the deliberate mistake!!!
The wing servos had been I stalled upside down this came about because I made up the Servo trays with the 2 plywood wing ribs ready for when I came to build the outer wings, I always check, ponder and recheck everything as the build progreses and this is why.

[Brian Taylor]

Hi, I am just about to start building the T21 and would like to say a big thank you for your very useful build thread.
I am also going to make my own suspension skid and was wondering if you made the rubber mounts yourself or if you found a supplier. Any pointers most welcome.
Brian

[Wayne]

Hi Brian
Here's the link for the rubber mounts I used from Amazon
These are similar to the ones used on my SG38 only smaller at 10mm
sourcing map M4 Rubber Mounts, 6pcs Male/Female Vibration Isolator Shock Absorber, for Garage Motor Air Compressor Car Boat Bobbins, D10mmxH10mm https://amzn.eu/d/3oYqXa7

The bottom fixing screws are from eBay 4mm x 8mm.

I simply installed 3 spruce cross members at the centre sections of the fusealarge formers, the front spruce is for the 2 screws for the attachment plate and the other 2 for and drilled out slightly smaller than the 4mm threaded rods attached to the rubber mounts and hand threaded them on, you could use a 4mm captive nut although I was happy with the hand tight fit, you'll need to remove them so you can cover the fusealarge bottom with plywood and then the covering, I'm using natural white oratex before reattaching.

The 2 front fixing screws on the brass attachment plate are servo mounting screws, you may have to trim the 2 that protrude through the plywood skid.

On another note about the plywood skin, I noticed another post somewhere on this forum about using or rather not using the 0.4mm plywood, instead using 0.6mm as it doesn't split and bends to contour much easier, if I was to build this kit again then I would use 0.6mm, yes ever so slightly heavier but negligible.

Just came across this post again:
viewtopic.php?p=26304#p26304

Hope this helps

[mchandrayan]

Thank you Ted for doing this thread.
I had bought the kit for the 1/6 T21 and started on the tail feathers, but discouraged by absence of online builds to check against the build was languishing.
Your thread will sure help kickstart my build and also help me to compare and correct when I get stuck. Keep up the good work

[Wayne]

Glad to be of help
So far I'm finding some of the build fiddly as some of the cut out parts are small, that said it is a 1/6 scale, in hindsight and as I've said earlier in my posts, I would have preferred a larger scale build ideally 1/4 Scale, so.maybe that'll be my next upscale build.

Please note:
This thread may go quite now n then for 2 reasons firstly it's almost spring, hopefully finish the build over next few weeks secondly I have other commitments so not always time to upload updates

Please feel free to ask any questions and I'll help.where I can.

[mchandrayan]

Thank you Ted. I am sure I will have questions when I restart on the build. Hope to do that once I am through with a Goldberg Chipmunk and a Phil Kent Aeronca C1