Composite ARF Impact
12-20-2004 | 01:05 PM
#280
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From: San Diego,
CA
RE: Impact
One other thing,
Make sure you have the right prop adapter before you make your motor mount, so you can account for the right clearance.
I tried a few different prop adapters, and I prefer the Graupner 6mm motor shaft with a 10mm prop shaft. I believe Steve also carries these.
This prop adapter comes with a threaded hole in the middle of the shaft that makes adding a spinner easy. I'm using the Tru Turn 3 3/8" (3 1/2" would be better) FAI spinner with a lightened back plate.
Pedro.
Make sure you have the right prop adapter before you make your motor mount, so you can account for the right clearance.
I tried a few different prop adapters, and I prefer the Graupner 6mm motor shaft with a 10mm prop shaft. I believe Steve also carries these.
This prop adapter comes with a threaded hole in the middle of the shaft that makes adding a spinner easy. I'm using the Tru Turn 3 3/8" (3 1/2" would be better) FAI spinner with a lightened back plate.
Pedro.
12-20-2004 | 02:00 PM
#282
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From: San Diego,
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RE: Impact
Norm,
I know this is a topic for a different thread so.........
could you send me an email on what and how you will be using the motor and what the performance is like?
Thanks,
Pedro
[email protected]
I know this is a topic for a different thread so.........
could you send me an email on what and how you will be using the motor and what the performance is like?
Thanks,
Pedro
[email protected]
12-20-2004 | 04:17 PM
#283
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From: Gothenburg, SWEDEN
RE: Impact
ORIGINAL: pbrantuas
Here's one with the motor mounted.
Pedro.
Here's one with the motor mounted.
Pedro.
Best regards,
Erik
12-20-2004 | 04:39 PM
#284
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From: San Diego,
CA
RE: Impact
Eric,
It's interesting that the Jeti people would say that an Advance 77-3p Opto controller is a no go for a 10s pack, and that 24 cells is the maximum when they advertise on the label that the controller is intended for 12-30 cells.
I have about 22 flights on mine with the NeuMotor setup on a 10s3p pack and so far so good. I have the timing set on "hard" and on the ground I'm pulling 55 amps. After a 10 minute flight the motor temp is about 105 degrees F, and the controller is about 120 degrees F.
Regards,
Pedro
It's interesting that the Jeti people would say that an Advance 77-3p Opto controller is a no go for a 10s pack, and that 24 cells is the maximum when they advertise on the label that the controller is intended for 12-30 cells.
I have about 22 flights on mine with the NeuMotor setup on a 10s3p pack and so far so good. I have the timing set on "hard" and on the ground I'm pulling 55 amps. After a 10 minute flight the motor temp is about 105 degrees F, and the controller is about 120 degrees F.
Regards,
Pedro
12-20-2004 | 05:29 PM
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From: Gothenburg, SWEDEN
RE: Impact
ORIGINAL: pbrantuas
Eric,
It's interesting that the Jeti people would say that an Advance 77-3p Opto controller is a no go for a 10s pack, and that 24 cells is the maximum when they advertise on the label that the controller is intended for 12-30 cells.
I have about 22 flights on mine with the NeuMotor setup on a 10s3p pack and so far so good. I have the timing set on "hard" and on the ground I'm pulling 55 amps. After a 10 minute flight the motor temp is about 105 degrees F, and the controller is about 120 degrees F.
Regards,
Pedro
Eric,
It's interesting that the Jeti people would say that an Advance 77-3p Opto controller is a no go for a 10s pack, and that 24 cells is the maximum when they advertise on the label that the controller is intended for 12-30 cells.
I have about 22 flights on mine with the NeuMotor setup on a 10s3p pack and so far so good. I have the timing set on "hard" and on the ground I'm pulling 55 amps. After a 10 minute flight the motor temp is about 105 degrees F, and the controller is about 120 degrees F.
Regards,
Pedro
You may want to ask them yourself. But they renamed it 75-3p Opto pretty early on and out 8-24 cells on the label. I guess there must have been some reason for them to do this. Though I don´t know what that would be. But if it´s running fine then by all means run it. I just thought you should know.
/Erik
12-20-2004 | 07:06 PM
#286
Senior Member
RE: Impact
RGreen, this IMPACT was the standard color scheme, not the red and white. But IF I were to get one, I would get the red and white and paint it myself. The stock scheme is much too busy.
I weighed the stab/elevator assy and rudder on my friend's IMPACT and thought these are much too heavy. The stab (including servos and linkages) is 12 ounces and the rudder is 3 1/2 ozs. This is an area that serious weight can be saved, especially for the guys building electric power into this model. These parts can be built from standard balsa veneered foam for half the weight.
Be that as it may, the model is of typical weight (about 10 1/2 lbs) with an internal combustion engine set-up, so even with the heavy tail, it's not terrible.
MattK
I weighed the stab/elevator assy and rudder on my friend's IMPACT and thought these are much too heavy. The stab (including servos and linkages) is 12 ounces and the rudder is 3 1/2 ozs. This is an area that serious weight can be saved, especially for the guys building electric power into this model. These parts can be built from standard balsa veneered foam for half the weight.
Be that as it may, the model is of typical weight (about 10 1/2 lbs) with an internal combustion engine set-up, so even with the heavy tail, it's not terrible.
MattK
01-01-2005 | 02:03 PM
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From: Oakland,
CA
RE: Impact
ORIGINAL: Andy P.
If you go to page 8 of this thread you will see my posting on how I set my Incidences, also if you follow that method the stab incidence will be zero and the fuz will also look as though it's at the correct flight attitude. Hope this helps.
If you go to page 8 of this thread you will see my posting on how I set my Incidences, also if you follow that method the stab incidence will be zero and the fuz will also look as though it's at the correct flight attitude. Hope this helps.
Andy,
I'm very close to "glueing" everything for my stab so I just want to make sure that I've understood you correctly...
Extended a line from the top of the chin cowl all the way back to the stab (30mm below the middle of the stab tube) - using this as my "center line". Propped up the model so that this line is perfectly horizontal from nose to tail and then I set the stab incidence to 0 based on this reference point.
Am I correct in my assumption of your writing?
[sm=thumbup.gif] or [sm=thumbdown.gif]
-Derek
01-01-2005 | 08:00 PM
#288
Senior Member
RE: Impact
Derek that's the same as placing a 33.5 mm block under the tail post, with the front of the fuse blocked up as Andy says. The fuse bottom will need to barely touch the building surface. That's is the correct factory fuse angle for things to work out correctly in knife edge. The stab needs zero and the wing about .25 positive.
MattK
MattK
01-01-2005 | 09:10 PM
#289
Senior Member
RE: Impact
In view of some latest developments, the broken fuselage I have in my shop will be sanded to remove the paint of the model, and the tail will be re-glassed completely around the fuse. I am using 2 oz glass cloth and am covering the area from the wing's trailing edge to the tail post, and going about halfway up on the fin. I am estimating approximately 3 1/2-4 oz weight gain. Since I will be using very lightweight tail surfaces on the model, the weight gain will be off set by the surfaces' weight so it should come out fine in the end. I will try to post some progress photos
Good luck to all who are finishing up the standard IMPACT
MattK
Good luck to all who are finishing up the standard IMPACT
MattK
01-02-2005 | 05:22 AM
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From: Leicester, , UNITED KINGDOM
RE: Impact
Hi Derek,
Yep youv'e got it!
After setting my Impact using this method I can confirm that the model is almost perfect with regards to trim. On the first flight with the model only very small down trim was applied ( approx 1 mm). The model tracked beautifully in all flight angles and the stall produced a very sedate drop of the nose followed by a perfect wings level shallow glide, awsome! The glide speed during landings can be slowed right up without any wing drop. My incidences are; zero down thrust, 3.5 degrees right thrust ( YS140lm - 15x12 APC - 30% wildcat 3DLV fuel ), +0.25 degrees on the wings and zero degrees on the stabs. I have chosen the rear tail servo set up without the tail incidence adjusters, the models c/g came in as close to perfect as you could wish. If you go to the comp-arf.co.uk site that Mark Shroeder has created, you will see the photo's of the set up method I posted earlier, well done Mark!!
Hope this helps.
Happy New Year to you all.
Andy.
Yep youv'e got it!
After setting my Impact using this method I can confirm that the model is almost perfect with regards to trim. On the first flight with the model only very small down trim was applied ( approx 1 mm). The model tracked beautifully in all flight angles and the stall produced a very sedate drop of the nose followed by a perfect wings level shallow glide, awsome! The glide speed during landings can be slowed right up without any wing drop. My incidences are; zero down thrust, 3.5 degrees right thrust ( YS140lm - 15x12 APC - 30% wildcat 3DLV fuel ), +0.25 degrees on the wings and zero degrees on the stabs. I have chosen the rear tail servo set up without the tail incidence adjusters, the models c/g came in as close to perfect as you could wish. If you go to the comp-arf.co.uk site that Mark Shroeder has created, you will see the photo's of the set up method I posted earlier, well done Mark!!
Hope this helps.
Happy New Year to you all.
Andy.
01-02-2005 | 02:08 PM
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From: Oakland,
CA
RE: Impact
ORIGINAL: Andy P.
Yep youv'e got it!
After setting my Impact using this method I can confirm that the model is almost perfect with regards to trim. On the first flight with the model only very small down trim was applied ( approx 1 mm). The model tracked beautifully in all flight angles and the stall produced a very sedate drop of the nose followed by a perfect wings level shallow glide, awsome! The glide speed during landings can be slowed right up without any wing drop. My incidences are; zero down thrust, 3.5 degrees right thrust ( YS140lm - 15x12 APC - 30% wildcat 3DLV fuel ), +0.25 degrees on the wings and zero degrees on the stabs. I have chosen the rear tail servo set up without the tail incidence adjusters, the models c/g came in as close to perfect as you could wish. If you go to the comp-arf.co.uk site that Mark Shroeder has created, you will see the photo's of the set up method I posted earlier, well done Mark!!
Yep youv'e got it!
After setting my Impact using this method I can confirm that the model is almost perfect with regards to trim. On the first flight with the model only very small down trim was applied ( approx 1 mm). The model tracked beautifully in all flight angles and the stall produced a very sedate drop of the nose followed by a perfect wings level shallow glide, awsome! The glide speed during landings can be slowed right up without any wing drop. My incidences are; zero down thrust, 3.5 degrees right thrust ( YS140lm - 15x12 APC - 30% wildcat 3DLV fuel ), +0.25 degrees on the wings and zero degrees on the stabs. I have chosen the rear tail servo set up without the tail incidence adjusters, the models c/g came in as close to perfect as you could wish. If you go to the comp-arf.co.uk site that Mark Shroeder has created, you will see the photo's of the set up method I posted earlier, well done Mark!!
Thanks Andy... I'm looking forward to some glueing now. [8D]
Did you use adjusters on the wings? I'm planning on using adjusters...
01-02-2005 | 02:11 PM
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From: Oakland,
CA
RE: Impact
ORIGINAL: Andy P.
I have chosen the rear tail servo set up without the tail incidence adjusters, the models c/g came in as close to perfect as you could wish. If you go to the comp-arf.co.uk site that Mark Shroeder has created, you will see the photo's of the set up method I posted earlier, well done Mark!!
I have chosen the rear tail servo set up without the tail incidence adjusters, the models c/g came in as close to perfect as you could wish. If you go to the comp-arf.co.uk site that Mark Shroeder has created, you will see the photo's of the set up method I posted earlier, well done Mark!!
One other thing... on your tail servo setup... did you mount them inside the stab or do they protrude into the fuse? How did you epoxy that balsa brace in the rear? There is no access except through the tail post...
01-03-2005 | 05:26 PM
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From: Mendota Hts.,
MN
RE: Impact
ORIGINAL: MTK
Derek that's the same as placing a 33.5 mm block under the tail post, with the front of the fuse blocked up as Andy says. The fuse bottom will need to barely touch the building surface. That's is the correct factory fuse angle for things to work out correctly in knife edge. The stab needs zero and the wing about .25 positive.
MattK
Derek that's the same as placing a 33.5 mm block under the tail post, with the front of the fuse blocked up as Andy says. The fuse bottom will need to barely touch the building surface. That's is the correct factory fuse angle for things to work out correctly in knife edge. The stab needs zero and the wing about .25 positive.
MattK
From the quote above can I assume that if I set the fuselage on the table and prop the tail up 33.5 mm that I'll get what I should? Haven't started yet but will soon and want to get it right!
Thanks,
Tom
01-03-2005 | 07:32 PM
#294
Senior Member
RE: Impact
Tom, that's correct. If you also blocked the front engine area, this would give much greater support to the assembly. The bottom of the fuse should be flush with the work surface. Be careful to shim the front appropriately, IF needed, to bring the tail post exactly perpendicular to your work surface. Brian's new fuse needed 1/32" shim on one side. That's minor misalignment considering how large the fuse is.
I have now received more emails from guys with failed tails. Not all fuses are affected of course. Its a small percentage. This is an otherwise fine product.
To CARF, Andreas, if you are listening, it would be so much easier to add a couple bulkheads in the tail when the fuses are being cast. These do not have to be elaborate. They simply need to support the fuse all the way around. The simplest is Carbon tow, around 12K, under the secondary internal glass layer, will provide plenty of support. One at the tail area, one mid-way and one at the wing trailing edge. (At least offer templates in your instructions so we can add balsa/glass formers.) The weight pick up would be less than an ounce. The idea is to reduce the span between supports, to greatly increase the natural harmonic frequency of the structure and take better advantage of the stiffness of the TAVS used. It will not be as easy a structure to buckle
To get an idea of what Im talking about fellas, take a couple sheets of paper and roll them up into tubes, overlap and tape the ends. Stand the first up and place some weights on it until it crushes. In the second tube, add two formers inside separated by equal distance, and do the crush experiment again. How much weight did it take ito crush the second?
MattK
I have now received more emails from guys with failed tails. Not all fuses are affected of course. Its a small percentage. This is an otherwise fine product.
To CARF, Andreas, if you are listening, it would be so much easier to add a couple bulkheads in the tail when the fuses are being cast. These do not have to be elaborate. They simply need to support the fuse all the way around. The simplest is Carbon tow, around 12K, under the secondary internal glass layer, will provide plenty of support. One at the tail area, one mid-way and one at the wing trailing edge. (At least offer templates in your instructions so we can add balsa/glass formers.) The weight pick up would be less than an ounce. The idea is to reduce the span between supports, to greatly increase the natural harmonic frequency of the structure and take better advantage of the stiffness of the TAVS used. It will not be as easy a structure to buckle
To get an idea of what Im talking about fellas, take a couple sheets of paper and roll them up into tubes, overlap and tape the ends. Stand the first up and place some weights on it until it crushes. In the second tube, add two formers inside separated by equal distance, and do the crush experiment again. How much weight did it take ito crush the second?
MattK
01-04-2005 | 12:43 AM
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From: Camberwell, AUSTRALIA
RE: Impact
A note just in case some may have missed it (and Matt may be talking about something more advanced) but I understand from CARF that the Impacts being shipped from now on do have reinforcement formers in the tail.
For those with models without these formers, the new instruction manual released a few weeks back has the plan for the formers as an addendum. They are not dissimilar to those in the ZN lIne models around the stab/fin area, and don't (as far as I can tell) include formers further up the fuz as Matt suggests. I agree with Matt in that formers further up the fuz to prevent any deformation under load would help strengthen the structure further. I guess the issue still comes back to weight.
For those with models without these formers, the new instruction manual released a few weeks back has the plan for the formers as an addendum. They are not dissimilar to those in the ZN lIne models around the stab/fin area, and don't (as far as I can tell) include formers further up the fuz as Matt suggests. I agree with Matt in that formers further up the fuz to prevent any deformation under load would help strengthen the structure further. I guess the issue still comes back to weight.
01-04-2005 | 05:06 AM
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From: Leicester, , UNITED KINGDOM
RE: Impact
Hi Guy's,
Firstly, Derek I didn't use wing adjusters on my Impact. David Gibbs fortunately was ahead of me with his build when I reached this stage, I decided that the set-up he was running with regards initial incidences showed the kind of flying qualities I was looking for. Measure several times, then glue!
My tail servo's are placed inside the stabs. I achieved this by cutting a small access panel on the underside but only big enough to place the servo bearers in position. I then slid the servo's in through the root former and secured them with the screws. Took me around 6 hours to complete, with the hatches re-fitted using self adhesive trim.
With regard to the fuselage strengthening at the rear of the fus, I installed the new formers before any flights were made, not easy!
I made up the formers and carried out a dry fit, this was achieved by drilling a 1.5mm hole along the horizontal axis of the horizontal former and tapped a thread for 2mm rod. I then made up an extension pole with a 2mm threaded end and attached the former to it. You can then slide the former all the way to the back of the fuselage and un-screw the rod, which leaves the former in place. Three hour epoxy and micro balloons were used as the bonding agent.
However, I still experienced a problem on the second trimming flight whereby after landing and retreiving the model from the flight line, I noticed a fracture/crease from the top of the fuselage to the bottom (vertical axis) around 4" in front of the new former.
Rudder flutter has been given as the reason for this, yet I have no slop in the closed loop and bottom hinge and in fact, all are still very much in tact! I'm also running an 11kg pull Digital servo on the rudder, JR DS8401, tremendous holding power.
So where do these flutter forces go? It has been explained to me that they travel along the fuselage with a rippleing/wave like effect around each side of the fuselage, couple this with the effects of using a closed loop system for the control and you have a compression element/force between the servo output shaft centre and the output horn on the rudder, over the length of the fuselage rear. Don't get me wrong, I'm not a self appraised expert in this field but merely a modeller who seeks guidance and listens with consideration to all coments made.
MY experience with MY particular model, tells me that extra strength is going to be essential around this area, you must make your own descision whilst completing yours.
A real shame with such a fantastic product! comp-arf and all the contributers to this products existance should be proud......................................
I'm off to think about were I go from here!
Andy.
Firstly, Derek I didn't use wing adjusters on my Impact. David Gibbs fortunately was ahead of me with his build when I reached this stage, I decided that the set-up he was running with regards initial incidences showed the kind of flying qualities I was looking for. Measure several times, then glue!
My tail servo's are placed inside the stabs. I achieved this by cutting a small access panel on the underside but only big enough to place the servo bearers in position. I then slid the servo's in through the root former and secured them with the screws. Took me around 6 hours to complete, with the hatches re-fitted using self adhesive trim.
With regard to the fuselage strengthening at the rear of the fus, I installed the new formers before any flights were made, not easy!
I made up the formers and carried out a dry fit, this was achieved by drilling a 1.5mm hole along the horizontal axis of the horizontal former and tapped a thread for 2mm rod. I then made up an extension pole with a 2mm threaded end and attached the former to it. You can then slide the former all the way to the back of the fuselage and un-screw the rod, which leaves the former in place. Three hour epoxy and micro balloons were used as the bonding agent.
However, I still experienced a problem on the second trimming flight whereby after landing and retreiving the model from the flight line, I noticed a fracture/crease from the top of the fuselage to the bottom (vertical axis) around 4" in front of the new former.
Rudder flutter has been given as the reason for this, yet I have no slop in the closed loop and bottom hinge and in fact, all are still very much in tact! I'm also running an 11kg pull Digital servo on the rudder, JR DS8401, tremendous holding power.
So where do these flutter forces go? It has been explained to me that they travel along the fuselage with a rippleing/wave like effect around each side of the fuselage, couple this with the effects of using a closed loop system for the control and you have a compression element/force between the servo output shaft centre and the output horn on the rudder, over the length of the fuselage rear. Don't get me wrong, I'm not a self appraised expert in this field but merely a modeller who seeks guidance and listens with consideration to all coments made.
MY experience with MY particular model, tells me that extra strength is going to be essential around this area, you must make your own descision whilst completing yours.
A real shame with such a fantastic product! comp-arf and all the contributers to this products existance should be proud......................................
I'm off to think about were I go from here!
Andy.
01-04-2005 | 05:20 AM
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From: Leicester, , UNITED KINGDOM
RE: Impact
Hi guy's,
One more thing, has anyone actually balanced the rudder by adding weight to the counter balance? It has been explained to me that this may actualy cure flutter problems before they start!!!!!!!
Regards,
Andy.
One more thing, has anyone actually balanced the rudder by adding weight to the counter balance? It has been explained to me that this may actualy cure flutter problems before they start!!!!!!!
Regards,
Andy.
01-04-2005 | 09:04 AM
#298
Senior Member
RE: Impact
Hello Andy, a statically balanced rudder will eliminate flutter. Except the rudder is already around 85 grams. Even if you partially balanced the rudder, say around 70% of the mass, one would need about another 30 grams or so, concentrated on the very edge of the short dynamic balancer. Of course one may always add a longer moment arm but that would look silly
Another approach which I favor, is to remove the stock part and build one from balsa. It will weigh in at about 45 grams. The problem of flutter is exacerbated as the surface mass increases, both in terms of initiating it and in terms of the amount of load that transfers back into the stucture
rgds,
Mattk
Another approach which I favor, is to remove the stock part and build one from balsa. It will weigh in at about 45 grams. The problem of flutter is exacerbated as the surface mass increases, both in terms of initiating it and in terms of the amount of load that transfers back into the stucture
rgds,
Mattk
01-04-2005 | 09:32 AM
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From: Oakland,
CA
RE: Impact
ORIGINAL: Andy P.
Hi Guy's,
Firstly, Derek I didn't use wing adjusters on my Impact. David Gibbs fortunately was ahead of me with his build when I reached this stage, I decided that the set-up he was running with regards initial incidences showed the kind of flying qualities I was looking for. Measure several times, then glue!
My tail servo's are placed inside the stabs. I achieved this by cutting a small access panel on the underside but only big enough to place the servo bearers in position. I then slid the servo's in through the root former and secured them with the screws. Took me around 6 hours to complete, with the hatches re-fitted using self adhesive trim.
With regard to the fuselage strengthening at the rear of the fus, I installed the new formers before any flights were made, not easy!
I made up the formers and carried out a dry fit, this was achieved by drilling a 1.5mm hole along the horizontal axis of the horizontal former and tapped a thread for 2mm rod. I then made up an extension pole with a 2mm threaded end and attached the former to it. You can then slide the former all the way to the back of the fuselage and un-screw the rod, which leaves the former in place. Three hour epoxy and micro balloons were used as the bonding agent.
However, I still experienced a problem on the second trimming flight whereby after landing and retreiving the model from the flight line, I noticed a fracture/crease from the top of the fuselage to the bottom (vertical axis) around 4" in front of the new former.
Rudder flutter has been given as the reason for this, yet I have no slop in the closed loop and bottom hinge and in fact, all are still very much in tact! I'm also running an 11kg pull Digital servo on the rudder, JR DS8401, tremendous holding power.
So where do these flutter forces go? It has been explained to me that they travel along the fuselage with a rippleing/wave like effect around each side of the fuselage, couple this with the effects of using a closed loop system for the control and you have a compression element/force between the servo output shaft centre and the output horn on the rudder, over the length of the fuselage rear. Don't get me wrong, I'm not a self appraised expert in this field but merely a modeller who seeks guidance and listens with consideration to all coments made.
MY experience with MY particular model, tells me that extra strength is going to be essential around this area, you must make your own descision whilst completing yours.
A real shame with such a fantastic product! comp-arf and all the contributers to this products existance should be proud......................................
I'm off to think about were I go from here!
Hi Guy's,
Firstly, Derek I didn't use wing adjusters on my Impact. David Gibbs fortunately was ahead of me with his build when I reached this stage, I decided that the set-up he was running with regards initial incidences showed the kind of flying qualities I was looking for. Measure several times, then glue!
My tail servo's are placed inside the stabs. I achieved this by cutting a small access panel on the underside but only big enough to place the servo bearers in position. I then slid the servo's in through the root former and secured them with the screws. Took me around 6 hours to complete, with the hatches re-fitted using self adhesive trim.
With regard to the fuselage strengthening at the rear of the fus, I installed the new formers before any flights were made, not easy!
I made up the formers and carried out a dry fit, this was achieved by drilling a 1.5mm hole along the horizontal axis of the horizontal former and tapped a thread for 2mm rod. I then made up an extension pole with a 2mm threaded end and attached the former to it. You can then slide the former all the way to the back of the fuselage and un-screw the rod, which leaves the former in place. Three hour epoxy and micro balloons were used as the bonding agent.
However, I still experienced a problem on the second trimming flight whereby after landing and retreiving the model from the flight line, I noticed a fracture/crease from the top of the fuselage to the bottom (vertical axis) around 4" in front of the new former.
Rudder flutter has been given as the reason for this, yet I have no slop in the closed loop and bottom hinge and in fact, all are still very much in tact! I'm also running an 11kg pull Digital servo on the rudder, JR DS8401, tremendous holding power.
So where do these flutter forces go? It has been explained to me that they travel along the fuselage with a rippleing/wave like effect around each side of the fuselage, couple this with the effects of using a closed loop system for the control and you have a compression element/force between the servo output shaft centre and the output horn on the rudder, over the length of the fuselage rear. Don't get me wrong, I'm not a self appraised expert in this field but merely a modeller who seeks guidance and listens with consideration to all coments made.
MY experience with MY particular model, tells me that extra strength is going to be essential around this area, you must make your own descision whilst completing yours.
A real shame with such a fantastic product! comp-arf and all the contributers to this products existance should be proud......................................
I'm off to think about were I go from here!
Thanks for the info with regard to the servos and the former. Getting the former in is no problem for me... its the glueing part.
I think I'm going to put a balsa crutch in the fuselage - all the way down to the back - hopefully this will strengthen it enough.
-Derek
01-04-2005 | 10:48 AM
#300
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From: Leicester, , UNITED KINGDOM
RE: Impact
Thanks Matt, just wondered if it would be a viable solution to the problem! clearly it is but at the cost of extra weight........Mmmmmm.
If you completed this model with the elevator servo/s in the cockpit area of the fuselage, the extra weight would not be that much of an issue in terms of achieving the reqd c/g.
Derek, sorry for mis-understanding your request, I simply mixed up the resin/balloons to a thickness that would not just run of the formers, thus allowing enough time to locate and place the formers in their final positions
Kind Regards,
Andy.
If you completed this model with the elevator servo/s in the cockpit area of the fuselage, the extra weight would not be that much of an issue in terms of achieving the reqd c/g.
Derek, sorry for mis-understanding your request, I simply mixed up the resin/balloons to a thickness that would not just run of the formers, thus allowing enough time to locate and place the formers in their final positions
Kind Regards,
Andy.
