New Composite ARF SU27
11-26-2018, 02:51 PM
#451
Ah, didn't know there was that limitation. As you now have only posted 2 replies, you will need to reply 8 more times (in this or any other thread) before you can post photos. I hope you do so, would love to see pics of your build. What did your final weight end up being?
11-26-2018, 10:54 PM
#452
Marcus - would be great to see some pictures. You just need to get your post count up a bit before you can post though 
I've been getting some work done on mine - wings and fins done and have started on the fuselage. The wings were interesting - I managed to use shorter servo arms than the manual recommends for the slats and flaps which gave a better mechanical set up. A friend mentioned a similar issue with the elevators so going to look at that next to se if I can get a better set up there which doesn't end up wound way back on the ATV's.
I've been getting some work done on mine - wings and fins done and have started on the fuselage. The wings were interesting - I managed to use shorter servo arms than the manual recommends for the slats and flaps which gave a better mechanical set up. A friend mentioned a similar issue with the elevators so going to look at that next to se if I can get a better set up there which doesn't end up wound way back on the ATV's.
11-27-2018, 10:51 AM
#454
Marcus - would be great to see some pictures. You just need to get your post count up a bit before you can post though
I've been getting some work done on mine - wings and fins done and have started on the fuselage. The wings were interesting - I managed to use shorter servo arms than the manual recommends for the slats and flaps which gave a better mechanical set up. A friend mentioned a similar issue with the elevators so going to look at that next to se if I can get a better set up there which doesn't end up wound way back on the ATV's.
I've been getting some work done on mine - wings and fins done and have started on the fuselage. The wings were interesting - I managed to use shorter servo arms than the manual recommends for the slats and flaps which gave a better mechanical set up. A friend mentioned a similar issue with the elevators so going to look at that next to se if I can get a better set up there which doesn't end up wound way back on the ATV's.
if you do the servo arms for the elevators like in the manual you can only use 30% of the servo way - thats not like it has to be...
11-27-2018, 02:39 PM
#455
Yea - I'm going to work on that. I've not started the servo set up for the tailerons yet but I'm going to go with shorter arms.
Got some more work done on mine today - off on a work trip for the next few days but will post some pictures next time I'm working on it. I'm enjoying the build
Got some more work done on mine today - off on a work trip for the next few days but will post some pictures next time I'm working on it. I'm enjoying the build
11-28-2018, 11:25 PM
#461
150kg ;-). We have a test procedure over 20kg dry, so makes little difference. Also single servo I don’t recommend, only one gear train in the servo to support shock loads. That is why we have two servos, not torque.
Even on the best, tightest servo gears, over time the vibrating surface while on the ground will wear the gear slop.
Even on the best, tightest servo gears, over time the vibrating surface while on the ground will wear the gear slop.
11-29-2018, 07:11 AM
#462
Join Date: Nov 2018
Location: France
Posts: 20
Likes: 0
Received 0 Likes
on
0 Posts
Hi,
My name is Patrick, I'm French and I'm living nearby Strasbourg in France.
Like you, I'm building a SU 27UB from Carf. I started my build mid 2017 and my target for maiden flight is March next year.
I still have to do the programing of the box, the weathering and marking.
Paint scheme I have chosen is Ukraine digital camo, that's reason why I've discovered this post and follow it carefully!
Weight of my jet is 22.6 kgs empty and will be in range of 28 kgs at tack-off.
Set up is following:
2 M166TS engines, 16.5 kgs trust each
Powerbox Royal
Landing gear from Airtech modified by myself with Electron retract motors.
Like Marcus, have to wait 10 posts before adding pictures...
Have great fligths..
My name is Patrick, I'm French and I'm living nearby Strasbourg in France.
Like you, I'm building a SU 27UB from Carf. I started my build mid 2017 and my target for maiden flight is March next year.
I still have to do the programing of the box, the weathering and marking.
Paint scheme I have chosen is Ukraine digital camo, that's reason why I've discovered this post and follow it carefully!
Weight of my jet is 22.6 kgs empty and will be in range of 28 kgs at tack-off.
Set up is following:
2 M166TS engines, 16.5 kgs trust each
Powerbox Royal
Landing gear from Airtech modified by myself with Electron retract motors.
Like Marcus, have to wait 10 posts before adding pictures...
Have great fligths..
11-30-2018, 03:11 AM
#464
Very nice Markus, I like that actuator on the speed brake, is that the one from Electron?
Hi I am Marcus from Germany and I also build a Carf SU27 last Winter and Summer 2018. It was not easy because we have a srict law in Germany that we can not fly over 25kg wet. So I had to make a lot of changes not to get too heavy. In September I had the maiden flight with the SU and three more flights. She flying great and I am thrilled! In this winter i will do the paint job and looking forward to the next season.
Here are some informations to my build:
2 x B100F engines - 12kg trust each
Powerbox champion SRS
titanium thrust tubes
only 2 x 50kg servos for both tailerons
no funktional slats
2 fuelbags
selfmade landing gears with beotec parts and elektron parts
selfmade Cockpit with some Carf parts
unilight lights
If you are interested I can post some pics from my build.
and sorry for my bad english
Here are some informations to my build:
2 x B100F engines - 12kg trust each
Powerbox champion SRS
titanium thrust tubes
only 2 x 50kg servos for both tailerons
no funktional slats
2 fuelbags
selfmade landing gears with beotec parts and elektron parts
selfmade Cockpit with some Carf parts
unilight lights
If you are interested I can post some pics from my build.
and sorry for my bad english
11-30-2018, 05:49 AM
#465
Join Date: Nov 2018
Location: France
Posts: 20
Likes: 0
Received 0 Likes
on
0 Posts
Hi Marcus,
I have the same linear servo (or actuator) for the speed brake. Mine is from Actuonix and the model is L12-100-50-6
My concern is to fine best compromise between force and speed. Mine has 5 kgs force and speed of 2 cms/s. what I'm afraid of is 5 kgs force is not enough to move the speed brake!
I can use another one with 17 kgs force but speed is 0.25 cm/s only, means it will take more than 20 s to have speed brake extended!!
so what is your type and does it work fine?
I have the same linear servo (or actuator) for the speed brake. Mine is from Actuonix and the model is L12-100-50-6
My concern is to fine best compromise between force and speed. Mine has 5 kgs force and speed of 2 cms/s. what I'm afraid of is 5 kgs force is not enough to move the speed brake!
I can use another one with 17 kgs force but speed is 0.25 cm/s only, means it will take more than 20 s to have speed brake extended!!
so what is your type and does it work fine?
11-30-2018, 05:50 AM
#466
Sin
I would not disregard the use of a single servo on the stab.
I dont have a Sukhoi but I do have CARF Mig 29 which has an all moving stab. with a pivot point well forward of the chord line, difficult to balance.
The more torque you have the better to resist flutter, a big threat to all moving stabs. Its not just about overcoming aerodynamic force.
My Mig suffered flutter on one stab. Due to in the thin walled pivot tube, now fixed with carbon plate reinforcement to capture the stab. Bolts.
Despite vigorous flutter the gear train of the single JR 6311 servo was undamaged. For even more torque, and yet better flutter resistanceI I now have the new Futaba HPS A700 servo which has 70 kg/cm of torque, seems like the perfect servo since the final gear in the exceptionally tight gear train is stainless steel, harder even then brass or aluminium or even titanium, (according to the Vickers and Rockwell scales ) so should be the ultimate in wear resistance.
A further benefit is that one servo reduces the chance of failure by 50 % .
Makes set up easier, too, as well as saving weight.
As always my comments are based on personal experience.
DG
Last edited by David Gladwin; 11-30-2018 at 06:01 AM.
11-30-2018, 07:05 AM
#467
I have just acquired a previously owned CARF SU27 with matrix gear. I need to reengineer the rear main gear door closure mechanism. Would appreciate some posts of video of the gear being actuated as well as close up photos of the actuator or air cylinder mechanism opening and closing the rear main gear door and how it was done without hitting the strut.
Thanks
Roy
Thanks
Roy
12-01-2018, 10:11 AM
#468
Hi Marcus,
I have the same linear servo (or actuator) for the speed brake. Mine is from Actuonix and the model is L12-100-50-6
My concern is to fine best compromise between force and speed. Mine has 5 kgs force and speed of 2 cms/s. what I'm afraid of is 5 kgs force is not enough to move the speed brake!
I can use another one with 17 kgs force but speed is 0.25 cm/s only, means it will take more than 20 s to have speed brake extended!!
so what is your type and does it work fine?
I have the same linear servo (or actuator) for the speed brake. Mine is from Actuonix and the model is L12-100-50-6
My concern is to fine best compromise between force and speed. Mine has 5 kgs force and speed of 2 cms/s. what I'm afraid of is 5 kgs force is not enough to move the speed brake!
I can use another one with 17 kgs force but speed is 0.25 cm/s only, means it will take more than 20 s to have speed brake extended!!
so what is your type and does it work fine?
yes I have the Actuonix Linear servo for the speed brake. I have the model: L16-100-35-6-R and it works well - I also think 5 kg´s is enough for the brake.
Best regards
Marcus
12-01-2018, 10:13 AM
#469
Hi,
My name is Patrick, I'm French and I'm living nearby Strasbourg in France.
Like you, I'm building a SU 27UB from Carf. I started my build mid 2017 and my target for maiden flight is March next year.
I still have to do the programing of the box, the weathering and marking.
Paint scheme I have chosen is Ukraine digital camo, that's reason why I've discovered this post and follow it carefully!
Weight of my jet is 22.6 kgs empty and will be in range of 28 kgs at tack-off.
Set up is following:
2 M166TS engines, 16.5 kgs trust each
Powerbox Royal
Landing gear from Airtech modified by myself with Electron retract motors.
Like Marcus, have to wait 10 posts before adding pictures...
Have great fligths..
My name is Patrick, I'm French and I'm living nearby Strasbourg in France.
Like you, I'm building a SU 27UB from Carf. I started my build mid 2017 and my target for maiden flight is March next year.
I still have to do the programing of the box, the weathering and marking.
Paint scheme I have chosen is Ukraine digital camo, that's reason why I've discovered this post and follow it carefully!
Weight of my jet is 22.6 kgs empty and will be in range of 28 kgs at tack-off.
Set up is following:
2 M166TS engines, 16.5 kgs trust each
Powerbox Royal
Landing gear from Airtech modified by myself with Electron retract motors.
Like Marcus, have to wait 10 posts before adding pictures...
Have great fligths..
12-01-2018, 10:26 AM
#470
150kg ;-). We have a test procedure over 20kg dry, so makes little difference. Also single servo I don’t recommend, only one gear train in the servo to support shock loads. That is why we have two servos, not torque.
Even on the best, tightest servo gears, over time the vibrating surface while on the ground will wear the gear slop.
I really appreciate your contribution and take it very seriously. But we have the weight Limit in Germany and I had to weigh up between the "risk" of the one servo method and the weight. The shock loads are an argument wich I see only by landings - even if the plane is rolling on uneven underground - I will have an eye on it and perhaps change after a season to the futaba A700 servos
Best regards
Marcus
12-01-2018, 04:22 PM
#471
Making progress on mine. Designing and printing lots of parts to mount stuff. I wanted to make a smoke tank to go in front of the main tanks, it had to fit from the cockpit... Happy with how it turned out. Just lots of cleaning up now. Still need a cockpit...
