The New F86D Dog Sabre
#1026
My Feedback: (3)
Nothing but frustration right now on the F86. I installed the air tanks I got from TBM, assuming they were fine. No manufacturer's mark on them. I spent days hunting for an air retract leak, which only appeared at all above the 50psi I had previously tested to. My right arm is about to fall off from pumping. Finally, last resort, I tipped the jet on it's nose and with a mirror, flashlight, the pump, and a squirt bottle of soapy water, I tested the tank hose fitting. To my surprise, I could see the air tank itself leaked out the swaged seam. Obviously, the tanks weren't pressure tested. So finally things made sense, but the tanks were heck to remove as I'd secured them with Goop. I think I'm back on track now though. Got two smaller ones at the LHS, and hooked them up in parallel. I've finally achieved 100psi, and I'm testing that level overnight. What a hassle and waste of time. GRRRRRrrrrrrrrrr!
#1027
My Feedback: (2)
I am fairly sure the field was Southwest or maybe mostly south. I was visiting my sister-in-law and they lived west of downtown and the field was south from their house. I also visited a hobby shop south of their house but don't remember the name.
I too have been frustrated with the F-86D. Most of the construction was acceptable but a lot of careless mistakes in construction. I actually stuck my thumb right through the canopy/hatch in two places during normal handling because the fiber glass layers were so thin in two spots. It is an easy fix but when I contacted Model Bau for paint to refinish the patch I was told they didn't have any alum. paint and it didn't matter because it wouldn't match any way.
Mine did not come with any tube to install in the fuselage to hold the main carbon spar. Why not, the manufacture has the correct tube in the wing to mate with the spar. I made my own out of fiber glass, and some guys are using a brass tube. If I used the holes provided to mount the horizontal stab the stab had about a 10 degree tilt in relation to the wing. It is easy to fix but frustrating.
My last revelation is the motor mount plates are not aligned properly with the tail pipe. They are probably only about 5-7 degrees off but will require shimming the motor to align the exhaust blast with the pipe.
I still feel he F-86D is a good value but it would cost practically nothing to fix my complaints in the first place,.
.
#1028
My Feedback: (3)
Man does your sentence sums up completely my thoughts. Doesn't add cost to the kit to do correctly what you're doing anyway. As for the spar tube; I didn't bother to use one at all. I just put the wings together, spar installed, shimmed the spar to the correct incidence angle, and glued it in place. So, yeah, the tube is permanent. For handling, you can't ask for a better thing to grab. I actually like having it there. And, for storage, it's no wider than the horiz. stabilizer anyway. I haven't run into a downside to this anyway, turning lemon into lemonade. For the turbine, has anyone run into problems putting the shutoff valve and filter between the pump and the engine? I've been advised by an expert it's possible to flame out the engine due to too many obstructions to flow, best to have nothing between the pump and engine.
#1030
<SNIP> For the turbine, has anyone run into problems putting the shutoff valve and filter between the pump and the engine? I've been advised by an expert it's possible to flame out the engine due to too many obstructions to flow, best to have nothing between the pump and engine.
Greg
#1033
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Join Date: Mar 2009
Location: Dudelange, LUXEMBOURG
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Things are changing in turbine technology.
With introduction of kerosene start, we had 2 electric valves on the pressure side. 1 for the start-up, one for normal operation (acting although as shut up valve).
Today one or both valves are integrated in the body of the turbine, but still present and still can leak and you have no influence.
I use an additional hand operated valve between pump and fuel cell (shut off after flight for fuelling and transport)
All tygon tubing are secured by wire.
Best regards
Flilek
With introduction of kerosene start, we had 2 electric valves on the pressure side. 1 for the start-up, one for normal operation (acting although as shut up valve).
Today one or both valves are integrated in the body of the turbine, but still present and still can leak and you have no influence.
I use an additional hand operated valve between pump and fuel cell (shut off after flight for fuelling and transport)
All tygon tubing are secured by wire.
Best regards
Flilek
#1034
My Feedback: (3)
Fuel valves and wired
Thanks for all the input on fuel valve and filter placement everyone. I've pretty much decided to go in this order, fuel valve, filter, pump, then turbine. Everything else is plumbed and waiting for that final decision. I have put nichrome wire on every tube connection that has pressure. See the picture, I also added tie wraps to hold the twisted ends down because every time I put my hands in there to do some work, they came out looking like a feral cat had attacked me!
Also, for the first time I accurately weighed the model with everything loaded and it came out to 16.5 pounds.
Also, for the first time I accurately weighed the model with everything loaded and it came out to 16.5 pounds.
Last edited by Pull Up Now!; 01-14-2014 at 06:27 AM.
#1035
I don't know what turbine you are using, but Kingtech recommends that the filter be downstream (between) the pump and turbine to filter anything coming out of the pump.
Regards,
Gus
Regards,
Gus
#1036
My Feedback: (3)
Yes, thanks for the info. I'm aware of the Kingtech fuel routing diagram. It's definitely a good debate. One compromise solution would be to put the valve before the pump and the filter after. I've contacted Kingtek to see if the pump has a history of shedding metal parts, and if there are any warranty implications to what they find in a defective engine.
#1037
My Feedback: (3)
I spoke with Barry from Kingtech regarding the placement order of the filter, pump, and valve components. He had an interesting take on it. First, he's never seen a K80 that starved for fuel or had acceleration hesitation due to fuel components AFTER the pump. He also said he's never seen or even heard of any pump fragments coming loose, though he acknowledged it's not impossible. The main thing is both the supplied valve and the filter are specifically designed to work under pressure, not suction. He recommends pump, then valve, then filter, then turbine. To address the squirting fuel issue, he recommends leaving the pump power connection accessible to pull the pump power if throttle cut doesn't first work. He said a switch could be used too. Barry also talked about going full throttle to spin up the engine electrically to get it cooled down, prevent warping of the hot parts. He said to read about that starting on page 49 of the new online manual. It sound to me like some situational context is really needed before doing that. Leaves me wondering why they allowed the type of the supplied valve to drive the location of it. Why not supply a valve that's suction proof, giving the customer a wider choice of locations?
I forgot to ask Barry about this, but the other day I noticed that the supplied clear tubing (that also fits the turbine festo fitting) does NOT fit the supplied blue filter. ***????? I heated it, and stretched it on but you have to know that is thinning the wall of the tube, thus weakening it. A festo reducer, which I didn't not have of course, would have been a better way to go. Maybe it's not too late, just delays the progress waiting for shipping.
I forgot to ask Barry about this, but the other day I noticed that the supplied clear tubing (that also fits the turbine festo fitting) does NOT fit the supplied blue filter. ***????? I heated it, and stretched it on but you have to know that is thinning the wall of the tube, thus weakening it. A festo reducer, which I didn't not have of course, would have been a better way to go. Maybe it's not too late, just delays the progress waiting for shipping.
Last edited by Pull Up Now!; 01-15-2014 at 04:17 AM.
#1038
My Feedback: (3)
I'd like to install a charging switch between the battery and the Xicoy. Maxx makes a high current switch, but to be sure, does anyone know about how much current the Xicoy draws assuming it's got to handle valves, it's circuit board, glow plug, starter motor, and pump all at once?
#1039
I'd like to install a charging switch between the battery and the Xicoy. Maxx makes a high current switch, but to be sure, does anyone know about how much current the Xicoy draws assuming it's got to handle valves, it's circuit board, glow plug, starter motor, and pump all at once?
KEEP IT SIMPLE. Just unplug/plug-in the connector. This also makes it easy to remove the battery for charging/balancing.
My 2 cents.
Greg
#1040
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Hi,
40 amps a re to much for a switch. Use the normal plug to disconnect.
Coming back to the filter.
My opinion an knowledge: Normal pumps have some running time (run in) at the factory (if the factory is serious) and no fragments will come out. I put the filter before the pump to prevent dirt getting in the pump. So it is close to impossible that fragments will go in the turbine.
I'm flying turbines for over 10 year an never had a problem with this set up.
Flilek
40 amps a re to much for a switch. Use the normal plug to disconnect.
Coming back to the filter.
My opinion an knowledge: Normal pumps have some running time (run in) at the factory (if the factory is serious) and no fragments will come out. I put the filter before the pump to prevent dirt getting in the pump. So it is close to impossible that fragments will go in the turbine.
I'm flying turbines for over 10 year an never had a problem with this set up.
Flilek
#1041
Junior Member
dear friend Flilek how have you been?
well i have saw that your F86 fligths very well ...... so mine is terrible to landing i do not what to do anymore... can you help me?
let tell what happend..
when i come to landing when the airplane touches down with the main landing gear it simply up again and stall, or when it come to ground it lands very well but a few moment it up again and stall its a challenge to keep in the ground..... i suspect is the Cg that is neutral...... 29 Cm from leading edge... i am thinking about to put some weigth in the nose to leave it with a weigth to leave easy to land...... i am using crow 1,3 cm and 3mm down in the profundor......... and flaps on 50 mm...... please help me cause i do not what to do more........... my airplane has about 100 fligts and i think that these 100 fligths i have just got to land perfect in 50........
i am going with 1/3 of engine until the final approach when i am in the final leg i put the engine on idle........
thank you very much
regards
Werner
well i have saw that your F86 fligths very well ...... so mine is terrible to landing i do not what to do anymore... can you help me?
let tell what happend..
when i come to landing when the airplane touches down with the main landing gear it simply up again and stall, or when it come to ground it lands very well but a few moment it up again and stall its a challenge to keep in the ground..... i suspect is the Cg that is neutral...... 29 Cm from leading edge... i am thinking about to put some weigth in the nose to leave it with a weigth to leave easy to land...... i am using crow 1,3 cm and 3mm down in the profundor......... and flaps on 50 mm...... please help me cause i do not what to do more........... my airplane has about 100 fligts and i think that these 100 fligths i have just got to land perfect in 50........
i am going with 1/3 of engine until the final approach when i am in the final leg i put the engine on idle........
thank you very much
regards
Werner
#1043
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Join Date: Mar 2009
Location: Dudelange, LUXEMBOURG
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dear friend Flilek how have you been?
well i have saw that your F86 fligths very well ...... so mine is terrible to landing i do not what to do anymore... can you help me?
let tell what happend..
when i come to landing when the airplane touches down with the main landing gear it simply up again and stall, or when it come to ground it lands very well but a few moment it up again and stall its a challenge to keep in the ground..... i suspect is the Cg that is neutral...... 29 Cm from leading edge... i am thinking about to put some weigth in the nose to leave it with a weigth to leave easy to land...... i am using crow 1,3 cm and 3mm down in the profundor......... and flaps on 50 mm...... please help me cause i do not what to do more........... my airplane has about 100 fligts and i think that these 100 fligths i have just got to land perfect in 50........
i am going with 1/3 of engine until the final approach when i am in the final leg i put the engine on idle........
thank you very much
regards
Werner
well i have saw that your F86 fligths very well ...... so mine is terrible to landing i do not what to do anymore... can you help me?
let tell what happend..
when i come to landing when the airplane touches down with the main landing gear it simply up again and stall, or when it come to ground it lands very well but a few moment it up again and stall its a challenge to keep in the ground..... i suspect is the Cg that is neutral...... 29 Cm from leading edge... i am thinking about to put some weigth in the nose to leave it with a weigth to leave easy to land...... i am using crow 1,3 cm and 3mm down in the profundor......... and flaps on 50 mm...... please help me cause i do not what to do more........... my airplane has about 100 fligts and i think that these 100 fligths i have just got to land perfect in 50........
i am going with 1/3 of engine until the final approach when i am in the final leg i put the engine on idle........
thank you very much
regards
Werner
Unfortunately I crashed my Dog Sabre on landing last year. The model is terrible on cross wind.
For CG I used the most aft position of the instructions.
To get the Sabre slow, I took of some material from the wing on the flaps gap. 1,3 cm on the ailerons for crow looks good. If I remember well, i had more down elevator to compensate. When I set crow and the speed was to high, the model raised the nose and climbed. On the leg parallel to the field, I have set throttle to low. At this point, I had a steady sink rate. Just added some power, when i was to short on final. When your model is too fast, it will jump. On the front leg, I added a aluminium block of 7-8mm to get the spring stiffer. My front leg was to soft and I had very few incidence to get the bird airborne. The gyro setting is very important in final to get no dutch roll.
Hope this helps you.
Best regards
Flilek
#1044
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Join Date: Sep 2006
Location: Altoona,
PA
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My F86 is now awaiting better weather in central PA and a road trip to a club field with waivered pilots for training and hopefully my waiver, at least to get started on it! I did a little detail in the cockpit, lets call it "stand-off scale", lol. Sorry for the blurred 1st picture.
#1048
My Feedback: (3)
My F86 is finally complete with the Kingtech K80G, and I tried starting it last night, first time. No luck.
I am using diesel fuel, 5% kingtech turbine oil. George, you're right, the settings I listed are from the manual's diesel column.
Using the parameters from the manual (diesel), the first start resulted in repeated "ignition fail" messages.
After a while, I progressively increased the pump pw ignition k (whatever that is) to 23. I also increased the "preheat fuel" to 30% progressively. Always the same thing, "ignition fail".
As background, I did prime the pump, and verified the fuel does flow thru the filter.
I also went thru the fuel valve test and could hear it clicking. During start up sequence, I can see the fuel pump led light pulsing.
Glow plug test ok, too. Altitude here is about 1000msl. The temperature was a bit cold, maybe 35degrees F. Maybe that's part of the issue.
During start attempts, the rpm shows around 2500. Is that normal? Anyone care to share their K80 model G settings?
I am using diesel fuel, 5% kingtech turbine oil. George, you're right, the settings I listed are from the manual's diesel column.
Using the parameters from the manual (diesel), the first start resulted in repeated "ignition fail" messages.
After a while, I progressively increased the pump pw ignition k (whatever that is) to 23. I also increased the "preheat fuel" to 30% progressively. Always the same thing, "ignition fail".
As background, I did prime the pump, and verified the fuel does flow thru the filter.
I also went thru the fuel valve test and could hear it clicking. During start up sequence, I can see the fuel pump led light pulsing.
Glow plug test ok, too. Altitude here is about 1000msl. The temperature was a bit cold, maybe 35degrees F. Maybe that's part of the issue.
During start attempts, the rpm shows around 2500. Is that normal? Anyone care to share their K80 model G settings?
Last edited by Pull Up Now!; 04-02-2014 at 09:02 PM.
#1049
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Hi, there is a Kingtech forum in the manufacturers area on this site. I am not sure that there were diesel settings for the K80, but I believe so. The service agent, Barry, has his number posted in that area also if you cannot find the answer that you need.
Happy flying, Bill
Happy flying, Bill
My F86 is finally complete with the Kingtech K80G, and I tried starting it last night, first time. No luck.
I am using diesel fuel, 5% kingtech turbine oil. George, you're right, the settings I listed are from the manual's diesel column.
Using the parameters from the manual (diesel), the first start resulted in repeated "ignition fail" messages.
After a while, I progressively increased the pump pw ignition k (whatever that is) to 30. I also increased the "preheat fuel" to 30% progressively. Always the same thing, "ignition fail".
As background, I did prime the pump, and verified the fuel does flow thru the filter.
I also went thru the fuel valve test and could hear it clicking. During start up sequence, I can see the fuel pump led light pulsing.
Glow plug test ok, too. Altitude here is about 1000msl. The temperature was a bit cold, maybe 35degrees F. Maybe that's part of the issue.
During start attempts, the rpm shows around 2500. Is that normal? Anyone care to share their K80 model G settings?
I am using diesel fuel, 5% kingtech turbine oil. George, you're right, the settings I listed are from the manual's diesel column.
Using the parameters from the manual (diesel), the first start resulted in repeated "ignition fail" messages.
After a while, I progressively increased the pump pw ignition k (whatever that is) to 30. I also increased the "preheat fuel" to 30% progressively. Always the same thing, "ignition fail".
As background, I did prime the pump, and verified the fuel does flow thru the filter.
I also went thru the fuel valve test and could hear it clicking. During start up sequence, I can see the fuel pump led light pulsing.
Glow plug test ok, too. Altitude here is about 1000msl. The temperature was a bit cold, maybe 35degrees F. Maybe that's part of the issue.
During start attempts, the rpm shows around 2500. Is that normal? Anyone care to share their K80 model G settings?
#1050
My Feedback: (3)
This evening, we got the Kingtech K80G running. First, I looked up the tailpipe and verified the glow igniter was working. It was. Next, I reduced the RPM Preheat setting to 4,000 rpm because it's pretty cold out. Next, I primed the burner for about 1.5 seconds. Then I initiated the start sequence and a bit of flame came out the circular burner. Moving in the right direction. At that point, I progressively increase the pump pw k one step at-a-time until it finally fired and flamed out at 28. One more tweak, moving pump pw k up to 29,. Nice. 143,000 rpms, about 520 degs C. Felt like close to 18lbs thrust. I'll measure that tomorrow night. Throttle is quite responsive,