Comp ARF BAE Hawk build thread
10-11-2013 | 06:02 PM
#1501
Here is a interesting CA Hawk story.
Today I helped a good friend maiden his Hawk. He asked me to work the trims for him on the initial flight.
He complained about it climbing and asked me to add DT for him. He kept telling me to keep adding DT. I did until there was none left to give.
He had to hold a lot of Down stick on top of the trim.
He is a very good pilot and did get it back on the ground without a scratch. It was scary to say the least.
The first thing we checked was his CG. It was right on. 195mm.
We kept scratching our heads, finally we checked the trim to see what it was actually doing.
Yes it was reversed.
He had just got the 12X transmitter back from Horizon for a upgrade to DSMX and a repair to his elevator trim which had stopped working.
Somehow they sent it back to him with the elevator trim reversed.
I never heard of that happening before. He is one lucky guy.
Stan
Today I helped a good friend maiden his Hawk. He asked me to work the trims for him on the initial flight.
He complained about it climbing and asked me to add DT for him. He kept telling me to keep adding DT. I did until there was none left to give.
He had to hold a lot of Down stick on top of the trim.
He is a very good pilot and did get it back on the ground without a scratch. It was scary to say the least.
The first thing we checked was his CG. It was right on. 195mm.
We kept scratching our heads, finally we checked the trim to see what it was actually doing.
Yes it was reversed.
He had just got the 12X transmitter back from Horizon for a upgrade to DSMX and a repair to his elevator trim which had stopped working.
Somehow they sent it back to him with the elevator trim reversed.
I never heard of that happening before. He is one lucky guy.
Stan
Last edited by tucson; 10-11-2013 at 06:05 PM.
10-11-2013 | 06:33 PM
#1502
My Feedback: (18)
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From: New City, NY
Here is a interesting CA Hawk story.
Today I helped a good friend maiden his Hawk. He asked me to work the trims for him on the initial flight.
He complained about it climbing and asked me to add DT for him. He kept telling me to keep adding DT. I did until there was none left to give.
He had to hold a lot of Down stick on top of the trim.
He is a very good pilot and did get it back on the ground without a scratch. It was scary to say the least.
The first thing we checked was his CG. It was right on. 195mm.
We kept scratching our heads, finally we checked the trim to see what it was actually doing.
Yes it was reversed.
He had just got the 12X transmitter back from Horizon for a upgrade to DSMX and a repair to his elevator trim which had stopped working.
Somehow they sent it back to him with the elevator trim reversed.
I never heard of that happening before. He is one lucky guy.
Stan
Today I helped a good friend maiden his Hawk. He asked me to work the trims for him on the initial flight.
He complained about it climbing and asked me to add DT for him. He kept telling me to keep adding DT. I did until there was none left to give.
He had to hold a lot of Down stick on top of the trim.
He is a very good pilot and did get it back on the ground without a scratch. It was scary to say the least.
The first thing we checked was his CG. It was right on. 195mm.
We kept scratching our heads, finally we checked the trim to see what it was actually doing.
Yes it was reversed.
He had just got the 12X transmitter back from Horizon for a upgrade to DSMX and a repair to his elevator trim which had stopped working.
Somehow they sent it back to him with the elevator trim reversed.
I never heard of that happening before. He is one lucky guy.
Stan
10-12-2013 | 12:54 AM
#1504
Mike
Was planning to build some more sets anyway probably 5/6 sets, I have to go through stock of what I have/not have and price up etc. I will be starting these sets at end of Oct....I know others have asked about the lights. They do take quite a time to make up as they are not your average mass produced Chinese item :-)
I have mine running on a 4700mAh Duralite Li-ion battery
Alan
Was planning to build some more sets anyway probably 5/6 sets, I have to go through stock of what I have/not have and price up etc. I will be starting these sets at end of Oct....I know others have asked about the lights. They do take quite a time to make up as they are not your average mass produced Chinese item :-)
I have mine running on a 4700mAh Duralite Li-ion battery
Alan
Thanks Alan! We talked briefly before about one of your lighting sets but, I had decided at the time to sell the back-up NIB Hawk I had here. Ultimately, I built it 
If you're doing lighting sets, let me know and I'd get one of those and a pitot tube from you. I don't want to put you out of your way to do it though, only if you're doing another one anyway.
Mike
If you're doing lighting sets, let me know and I'd get one of those and a pitot tube from you. I don't want to put you out of your way to do it though, only if you're doing another one anyway.Mike
Last edited by fireblade5437; 10-12-2013 at 12:59 AM.
10-12-2013 | 04:06 AM
#1505
My Feedback: (6)
Mike
Was planning to build some more sets anyway probably 5/6 sets, I have to go through stock of what I have/not have and price up etc. I will be starting these sets at end of Oct....I know others have asked about the lights. They do take quite a time to make up as they are not your average mass produced Chinese item :-)
I have mine running on a 4700mAh Duralite Li-ion battery
Alan
Was planning to build some more sets anyway probably 5/6 sets, I have to go through stock of what I have/not have and price up etc. I will be starting these sets at end of Oct....I know others have asked about the lights. They do take quite a time to make up as they are not your average mass produced Chinese item :-)
I have mine running on a 4700mAh Duralite Li-ion battery
Alan
Mike
10-12-2013 | 05:46 AM
#1506
I really Don't know what they would have done.
They could not wiggle out of that one, but replacing a 9000 dollar jet, I don't know what excuse they could use.
What do you think they would have done??
Stan
10-12-2013 | 08:14 AM
#1507
Stan
Denied liability I should think!
RC suppliers are one group of retailers that always seem to think that they should be untouchable when it comes to liability! We do/would not get away with it in industry!
Alan
Denied liability I should think!
RC suppliers are one group of retailers that always seem to think that they should be untouchable when it comes to liability! We do/would not get away with it in industry!
Alan
10-12-2013 | 11:02 AM
#1508
My Feedback: (29)
Joined: Jan 2002
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From: Hamilton,
ON, CANADA
Here is a interesting CA Hawk story.
Today I helped a good friend maiden his Hawk. He asked me to work the trims for him on the initial flight.
He complained about it climbing and asked me to add DT for him. He kept telling me to keep adding DT. I did until there was none left to give.
He had to hold a lot of Down stick on top of the trim.
He is a very good pilot and did get it back on the ground without a scratch. It was scary to say the least.
The first thing we checked was his CG. It was right on. 195mm.
We kept scratching our heads, finally we checked the trim to see what it was actually doing.
Yes it was reversed.
He had just got the 12X transmitter back from Horizon for a upgrade to DSMX and a repair to his elevator trim which had stopped working.
Somehow they sent it back to him with the elevator trim reversed.
I never heard of that happening before. He is one lucky guy.
Stan
Today I helped a good friend maiden his Hawk. He asked me to work the trims for him on the initial flight.
He complained about it climbing and asked me to add DT for him. He kept telling me to keep adding DT. I did until there was none left to give.
He had to hold a lot of Down stick on top of the trim.
He is a very good pilot and did get it back on the ground without a scratch. It was scary to say the least.
The first thing we checked was his CG. It was right on. 195mm.
We kept scratching our heads, finally we checked the trim to see what it was actually doing.
Yes it was reversed.
He had just got the 12X transmitter back from Horizon for a upgrade to DSMX and a repair to his elevator trim which had stopped working.
Somehow they sent it back to him with the elevator trim reversed.
I never heard of that happening before. He is one lucky guy.
Stan
10-16-2013 | 10:15 PM
#1510
My Feedback: (3)
I noticed that one of the main gear air cylinders is sticking during a portion of its travel. I would like to fix it. I disassembled the main gear and removed the air cylinder. Then I unscrewed the square mounting block from one end and the air fitting from the other end. I was able to see into the open end of the cylinder bore on the shaft side and lubricate the piston with BVM air gear oil. But it is still sticking/moving roughly during the last 10mm of travel. Is it possible to remove the cap from the opposite end of the cylinder and remove the piston to inspect the bore and the 'O' ring? I have no idea what the piston is hanging up on but it is not smooth in that area. Maybe I can hand lap it smooth with very fine abrasive if I can find the imperfection.
Last edited by husafreak; 10-16-2013 at 10:17 PM.
10-16-2013 | 10:21 PM
#1511
Thread Starter
I noticed that one of the main gear air cylinders is sticking during a portion of its travel. I would like to fix it. I disassembled the main gear and removed the air cylinder. Then I unscrewed the square mounting block from one end and the air fitting from the other end. I was able to see into the open end of the cylinder bore on the shaft side and lubricate the piston with BVM air gear oil. But it is still sticking/moving roughly during the last 10mm of travel. Is it possible to remove the cap from the opposite end of the cylinder and remove the piston to inspect the bore and the 'O' ring? I have no idea what the piston is hanging up on but it is not smooth in that area. Maybe I can hand lap it smooth with very fine abrasive if I can find the imperfection.
Check the rod more than the cylinder, there would have to be a big dent in the cylinder wall to restrict that. You sure its not mechanical on the slider? In the yoke too?
Dave
10-17-2013 | 01:52 AM
#1512
I never have had a problem with the cylinders front or back the maching is very good, though I had problem as I have posted in the past about the pivoting shaft picking up with the bushes. As these are both made out of an alloy, one of mine completely jammed whilst initially setting them up. I changed these for phosphor bronze bushes with steel shafts which made for a very smooth running retract
Have now finished the tail plane and ready for re-install back on to the Hawk.. (all the probes keep getting in the way
)
Alan
Have now finished the tail plane and ready for re-install back on to the Hawk.. (all the probes keep getting in the way
)Alan
Last edited by fireblade5437; 10-17-2013 at 02:06 AM.
10-17-2013 | 01:04 PM
#1513
My Feedback: (3)
I was able to see into the bore and there was definitely a shiny ring which would catch the piston. I spent hours with oily 1200/1500/2500 grit paper on little carved sticks and dowels and got it smoothed out. It is much smoother now.
I am also going to bite the bullet and redo the mounting of the main gear. On my hawk I just dropped the gear in place and drilled holes when building it. This left me with tires and strut assemblies that are coming within a mm or two of the wing skin going in and out. Just a matter of time until one catches. I'll just drill out the bolt holes, epoxy in 1/4 " dowels, open the plywood gear plates to allow the gear to angle more forward in the well and operate with reasonable clearance. So watch out for that if you are starting to build.
I am also going to bite the bullet and redo the mounting of the main gear. On my hawk I just dropped the gear in place and drilled holes when building it. This left me with tires and strut assemblies that are coming within a mm or two of the wing skin going in and out. Just a matter of time until one catches. I'll just drill out the bolt holes, epoxy in 1/4 " dowels, open the plywood gear plates to allow the gear to angle more forward in the well and operate with reasonable clearance. So watch out for that if you are starting to build.
10-21-2013 | 07:56 AM
#1514
Re-installed the tail plane, thought I might have to reset back up the current ie interaction of the two 8911 servos with un bolting etc but both servos still perfectly matched with the settings I did in the Cockpit Powerbox...
Looking forward to it taking to the air again...
Alan
Looking forward to it taking to the air again...
Alan
Last edited by fireblade5437; 10-21-2013 at 08:23 AM.
10-21-2013 | 01:48 PM
#1515
My Feedback: (25)
Finally got my Navy scheme hawk in so now i can take part in the thread instead of just creeping around in it. Great service from Andy Kane before and after the sale.
A few questions now.
In the manual it states servos with a minimum of 11KG required? Thats about 388 ounces. Seems awfully excessive not so much for the stabs and rudder, but for the ailerons? However it also states that an 8411 or 8711 may be used???
Theres a big difference in strength between the 8411 advertised at 155oz and the 8711 at over 400oz?
I have some 8411s that i was planning on using for the ailerons as well as some futaba 9156s and savox 1258TG and 1256TGs..(I trust all of these equally, and they are all nearly identical in size) The only ones I was planning on having to purchase were some
8711s or 9157s for the elevators.
So why the large discrepancy in the servo torque requirement? just seems odd for as small as the ailerons are and as little movement thats required of them. Dont get me wrong though Im all about "over building" the airplane. Better to not need it and have than need it and not have it..
A few questions now.
In the manual it states servos with a minimum of 11KG required? Thats about 388 ounces. Seems awfully excessive not so much for the stabs and rudder, but for the ailerons? However it also states that an 8411 or 8711 may be used???
Theres a big difference in strength between the 8411 advertised at 155oz and the 8711 at over 400oz?
I have some 8411s that i was planning on using for the ailerons as well as some futaba 9156s and savox 1258TG and 1256TGs..(I trust all of these equally, and they are all nearly identical in size) The only ones I was planning on having to purchase were some
8711s or 9157s for the elevators.
So why the large discrepancy in the servo torque requirement? just seems odd for as small as the ailerons are and as little movement thats required of them. Dont get me wrong though Im all about "over building" the airplane. Better to not need it and have than need it and not have it..
10-21-2013 | 01:57 PM
#1516
Thread Starter
Finally got my Navy scheme hawk in so now i can take part in the thread instead of just creeping around in it. Great service from Andy Kane before and after the sale.
A few questions now.
In the manual it states servos with a minimum of 11KG required? Thats about 388 ounces. Seems awfully excessive not so much for the stabs and rudder, but for the ailerons? However it also states that an 8411 or 8711 may be used???
Theres a big difference in strength between the 8411 advertised at 155oz and the 8711 at over 400oz?
I have some 8411s that i was planning on using for the ailerons as well as some futaba 9156s and savox 1258TG and 1256TGs..(I trust all of these equally, and they are all nearly identical in size) The only ones I was planning on having to purchase were some
8711s or 9157s for the elevators.
So why the large discrepancy in the servo torque requirement? just seems odd for as small as the ailerons are and as little movement thats required of them. Dont get me wrong though Im all about "over building" the airplane. Better to not need it and have than need it and not have it..
A few questions now.
In the manual it states servos with a minimum of 11KG required? Thats about 388 ounces. Seems awfully excessive not so much for the stabs and rudder, but for the ailerons? However it also states that an 8411 or 8711 may be used???
Theres a big difference in strength between the 8411 advertised at 155oz and the 8711 at over 400oz?
I have some 8411s that i was planning on using for the ailerons as well as some futaba 9156s and savox 1258TG and 1256TGs..(I trust all of these equally, and they are all nearly identical in size) The only ones I was planning on having to purchase were some
8711s or 9157s for the elevators.
So why the large discrepancy in the servo torque requirement? just seems odd for as small as the ailerons are and as little movement thats required of them. Dont get me wrong though Im all about "over building" the airplane. Better to not need it and have than need it and not have it..
The twin servos for the stab were for holding power and backlash resistance, I was asked if one 8711/8911 would be enough and I said torque wise, but not gear train/flutter resistance enough.
So two servos of 11KG+ are OK, but many many models and the thread starter still flying with two 8711's tells me its the best set-up
Dave Wilshere
PS Welcome to the thread!
10-21-2013 | 02:26 PM
#1518
Thread Starter
10-21-2013 | 07:31 PM
#1520
My Feedback: (25)
Ok so the standard 2.2 kg per pound is not the proper conversion here...not trying to be argumentative I just want to have a proper understanding. so an 11KG servo (kg-cm) is roughly 152.7 oz (oz-in)....thank you Dave and Alan for clearing that up for me.
I'm looking forward to starting the build in a few weeks. I just received my Titan SE from Jetcat I had it upgraded to the billet compressor wheel, latest ecu update with 3s life compatibility, and kero start.. I would prefer a 120-140 for this airframe but the Titan is
what I have laying around at the moment.
I'm looking forward to starting the build in a few weeks. I just received my Titan SE from Jetcat I had it upgraded to the billet compressor wheel, latest ecu update with 3s life compatibility, and kero start.. I would prefer a 120-140 for this airframe but the Titan is
what I have laying around at the moment.
10-22-2013 | 05:58 AM
#1521
Re-installed the tail plane, thought I might have to reset back up the current ie interaction of the two 8911 servos with un bolting etc but both servos still perfectly matched with the settings I did in the Cockpit Powerbox...
Looking forward to it taking to the air again...
Alan
Looking forward to it taking to the air again...
Alan
Alan , can you attach a few ore pics, the plane is beautiful. interested in how you did the opening/intake at the top for ( round grey) , and any naca openings
also the some of the panel lines that came with my model ( i took the all white ) , are covered by paint probably touched up after coming out of the mold and wondering how to re-etch them without damaging by mistake the glass
any comments?
thx
10-22-2013 | 07:31 AM
#1522
Dave - i have savox 1256tg planned for the ailerons ,
you mention 19mm servis, so will these not work?
[h=3]Specs:
Length:1.59 in (40.4 mm)
Width:0.79 in (20.1 mm)
Height:1.46 in (37.1 mm)[/h]
10-22-2013 | 08:59 AM
#1523
Junior Member
Joined: Nov 2009
Posts: 11
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From: , GERMANY
I have fitted the SA-1256TG all around my Hawk. Works perfect in every position, so for the ailerons, too. Good choice!
Regards
Stephan
10-22-2013 | 09:49 AM
#1524
Thread Starter
You will need to take all the support bridge down on the rear edge. You can sand down the servo mount slightly before gluing as its cut for the 20.5mm 8711. Like Stephan says, they will fit
Dave
Dave
10-22-2013 | 02:52 PM
#1525
Izzy
Will dig some pics out when back home as away with work
The top APU vent was made from a 32mm water pipe fitting right angle low profile which was glued in with Hysol, note Hysol will not stick PVC pipe fittings but if you glue around the recessed edge of the fitting the Hysol will then hold very securely to the fibreglass
the NACA openings were cut as per panel line then I cut from abs thin plastic card the same shape as the cut out but about 2mm larger all round. Then I used green zap glue and kicker to glue sides on then sand at angle then tack into fuselage with zap and kicker then put fillet of Hysol either side (NACA was painted with 2k primer then top coat applied before gluing in place)
I would not try and recut panel lines in to the fibreglass, one way I have used before is to mask panel lines with very fine tape 0.5-1mm and then when you spray your primer over fibreglass two coats you can pull the lines off and you are left with new panel line etc
Some of the panel lines on the CARF Hawk are good but some fade out completely
Alan
Will dig some pics out when back home as away with work
The top APU vent was made from a 32mm water pipe fitting right angle low profile which was glued in with Hysol, note Hysol will not stick PVC pipe fittings but if you glue around the recessed edge of the fitting the Hysol will then hold very securely to the fibreglass
the NACA openings were cut as per panel line then I cut from abs thin plastic card the same shape as the cut out but about 2mm larger all round. Then I used green zap glue and kicker to glue sides on then sand at angle then tack into fuselage with zap and kicker then put fillet of Hysol either side (NACA was painted with 2k primer then top coat applied before gluing in place)
I would not try and recut panel lines in to the fibreglass, one way I have used before is to mask panel lines with very fine tape 0.5-1mm and then when you spray your primer over fibreglass two coats you can pull the lines off and you are left with new panel line etc
Some of the panel lines on the CARF Hawk are good but some fade out completely
Alan
\
Alan , can you attach a few ore pics, the plane is beautiful. interested in how you did the opening/intake at the top for ( round grey) , and any naca openings
also the some of the panel lines that came with my model ( i took the all white ) , are covered by paint probably touched up after coming out of the mold and wondering how to re-etch them without damaging by mistake the glass
any comments?
thx
Alan , can you attach a few ore pics, the plane is beautiful. interested in how you did the opening/intake at the top for ( round grey) , and any naca openings
also the some of the panel lines that came with my model ( i took the all white ) , are covered by paint probably touched up after coming out of the mold and wondering how to re-etch them without damaging by mistake the glass
any comments?
thx
Last edited by fireblade5437; 10-22-2013 at 02:58 PM.
