700 My New T-Rex 700X Build
- Thread starter Heliman450
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Heliman450
Well-Known Member
Well taken Steve! It demonstrates very well how close the inspections need to be.
trainrider06
Active Member
Rodney, Yes it is pretty quiet but it's not due to a belt drive because this one is all gears and TT tail drive. The actual drive train is the same as the previous 700L. It's only the new Trex 470 that has gone to belt tail, maybe Align are saving the belt conversion for the next model of 700
Ah well dang I thought it did have one. Yep I am sure it'll probably be on the next one.....still that baby is quiet! Very nice!
trainrider06
Active Member
Ah! This is true! I didn't know they had helical tail drive gears on em.
Smoggie
Well-Known Member
It's just the spur gears that are helical cut, the bevel gears either end of the TT are straight cut, but they run quiet enough.
Talking on bevel gears.. Phil, the mesh of the front bevels on my 700X (both of them!) wasn't as tight as it could be, so i stuck in a 0.2mm shimin to reduce the play. I could have probably got a thicker shim in there but I'll let it bed in and see if it could use any more adjustment. It's good to have minimal play on these gears, it helps prevent stripping (not that that's really a problem on the 700)
Talking on bevel gears.. Phil, the mesh of the front bevels on my 700X (both of them!) wasn't as tight as it could be, so i stuck in a 0.2mm shimin to reduce the play. I could have probably got a thicker shim in there but I'll let it bed in and see if it could use any more adjustment. It's good to have minimal play on these gears, it helps prevent stripping (not that that's really a problem on the 700)
Heliman450
Well-Known Member
Hi Steve, thanks for the heads-up on that. Tomorrow, I'm starting on my Axon setup beginning with refitting the tail boom so that's excellent timing. I'll let you know how that goes later in the day. My wife's got something on for the next four days, so maybe I'll get plenty of time to complete the job.
Heliman450
Well-Known Member
Hi all, latest photos to update you on my progress.
#1
#2 
#3 
#4
#5 
The gyro isn't fixed in yet. #1 & 2 show how I decided to cut off the rubber covers to give a more flexible turn into the ports. #4 shows how I decided for an external route in for three of the servo leads, which also lines them up better into the ports to relieve the stress on the wires. I decided to put a blank plug into port 4, which helps to hold the others into the housing better.
Finally, #5 is everything ready for powering up tomorrow and going through the setup process. Fingers crossed.
#1
#2 #3 #4
#5 The gyro isn't fixed in yet. #1 & 2 show how I decided to cut off the rubber covers to give a more flexible turn into the ports. #4 shows how I decided for an external route in for three of the servo leads, which also lines them up better into the ports to relieve the stress on the wires. I decided to put a blank plug into port 4, which helps to hold the others into the housing better.
Finally, #5 is everything ready for powering up tomorrow and going through the setup process. Fingers crossed.
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Smoggie
Well-Known Member
Good work Phil.. A little tip on the braid (if you dont know already). Cut the braid maybe 6mm long on each end then apply heat from a hot air stripper or a lighter/match. The ends of the braid will melt together which prevents it unraveling. For neatest results now slip a short length of heatshrink over the ends of the braid and shrink it down.
Just out of curiosity... without the rubber covers on the servo leads could the FBL not have been mounted in it's 'default' position up front?
I got three more flights on my 700X during my lunchbreak at work today. Conditions for flying were close to perfect but a bit cold. All flights went without a hitch. I want through the Vbar's tail control loop optimisation process which auto adjusts the tail stop gains. Basically after activating the optimisation you just take off and do a few fast pirouettes with hard stops in alternate directions. The calibration numbers looked good so I think that's all the fine tuning done, I can just fly it from now on.
It's 11 flights now since the mishap so confidence is growing that the problem is fixed.
Just out of curiosity... without the rubber covers on the servo leads could the FBL not have been mounted in it's 'default' position up front?
I got three more flights on my 700X during my lunchbreak at work today. Conditions for flying were close to perfect but a bit cold. All flights went without a hitch. I want through the Vbar's tail control loop optimisation process which auto adjusts the tail stop gains. Basically after activating the optimisation you just take off and do a few fast pirouettes with hard stops in alternate directions. The calibration numbers looked good so I think that's all the fine tuning done, I can just fly it from now on.
It's 11 flights now since the mishap so confidence is growing that the problem is fixed.
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Heliman450
Well-Known Member
Cheers Steve,
I used my wife's hot air blower that she uses for her greeting cards 'business'. The ends melted together quite well but opened out like a flower, which wasn't so bad as it worked well as a funnel. I used about 2 cm of heat shrink at the top end to hold them all together and then clipped it to the body. I considered using some heat shrink on the top of the mesh but wanted to see how the wires at the gyro end work first.
I didn't think to return to the other location but it may still be a bit tight. Maybe it's worth a try in future should I need to do a strip down for any reason. I want to make some progress now that I'm ready
I need to catch up on you and I'm keen to see how the Axon works.
An E-Mail came through today to tell me that the programming box of tricks has arrived for the ESC, so I'll be able to do that, too.
Well done on the replacement heli. Are you still intending to order up new parts to eventually have two completed birds or just a lot of bits if needed?
I used my wife's hot air blower that she uses for her greeting cards 'business'. The ends melted together quite well but opened out like a flower, which wasn't so bad as it worked well as a funnel. I used about 2 cm of heat shrink at the top end to hold them all together and then clipped it to the body. I considered using some heat shrink on the top of the mesh but wanted to see how the wires at the gyro end work first.
I didn't think to return to the other location but it may still be a bit tight. Maybe it's worth a try in future should I need to do a strip down for any reason. I want to make some progress now that I'm ready
I need to catch up on you and I'm keen to see how the Axon works.An E-Mail came through today to tell me that the programming box of tricks has arrived for the ESC, so I'll be able to do that, too.
Well done on the replacement heli. Are you still intending to order up new parts to eventually have two completed birds or just a lot of bits if needed?
Smoggie
Well-Known Member
I was toying with getting the parts to complete the second heli.. The guy who sold the airframe also had the 130A ESC and the full set of servos, and he was doing a good deal so i couldnt resist
So other than the bits i stole for donor parts i have all it would take to build another 700X !
I kinda have plans for the ESC though (my goblin 630) and the servos (to go in my Compass 7HV).. so I'll have to have a think about it.
I also got another programming box with the ESC, so i have a spare one of those too. This one is the Align version but it's the same thing as the Hobbywing one except for the name. That will go on ebay as i have no use for two of them.
PS.. when applying heat on the braid make sure to just apply heat to the very end, that way it should not open up. A lighter is a good way to do it.
So other than the bits i stole for donor parts i have all it would take to build another 700X !I kinda have plans for the ESC though (my goblin 630) and the servos (to go in my Compass 7HV).. so I'll have to have a think about it.
I also got another programming box with the ESC, so i have a spare one of those too. This one is the Align version but it's the same thing as the Hobbywing one except for the name. That will go on ebay as i have no use for two of them.
PS.. when applying heat on the braid make sure to just apply heat to the very end, that way it should not open up. A lighter is a good way to do it.
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Heliman450
Well-Known Member
Hi all, bad news to report............
#1
#2 
I carried out a successful bind to my Jeti DC-14 and then powered up in the normal way only to be 'enveloped' in smoke. You can imagine my reaction and I immediately disconnected the battery. Photo #1 is the source of the smoke, the patch cable between Rx. and the Axon. I checked out what was wrong and discovered that the throttle plug was stepped back one pin in the '#6' port of the Axon. As you can see in photo #2 there is a further row of pins on the right-hand side that run at right angles to the others and a gap so that the signal wire of the throttle plug must have been in the live position and the live to the neutral. I obviously didn't locate the throttle plug properly into the port causing the short.
At the moment, I don't know if there is any other damage inside the Axon or the Rx. The Axon works OK when connected to the PC via the USB cable but I didn't spend any more time today wanting to first check through the documentation and, if necessary, send a query into the guys at Bavarian Demon as I'm not sure what else might have got fried by the event due to not having a wiring diagram of the internals. I seem to recall reading something in the Axon manual that there is internal protection against short circuits but that's a matter for my checking the document.
When I feel more inclined after changing my underpants, I'll return to carry on tomorrow. Fingers crossed.
#1
#2 I carried out a successful bind to my Jeti DC-14 and then powered up in the normal way only to be 'enveloped' in smoke. You can imagine my reaction and I immediately disconnected the battery. Photo #1 is the source of the smoke, the patch cable between Rx. and the Axon. I checked out what was wrong and discovered that the throttle plug was stepped back one pin in the '#6' port of the Axon. As you can see in photo #2 there is a further row of pins on the right-hand side that run at right angles to the others and a gap so that the signal wire of the throttle plug must have been in the live position and the live to the neutral. I obviously didn't locate the throttle plug properly into the port causing the short.
At the moment, I don't know if there is any other damage inside the Axon or the Rx. The Axon works OK when connected to the PC via the USB cable but I didn't spend any more time today wanting to first check through the documentation and, if necessary, send a query into the guys at Bavarian Demon as I'm not sure what else might have got fried by the event due to not having a wiring diagram of the internals. I seem to recall reading something in the Axon manual that there is internal protection against short circuits but that's a matter for my checking the document.
When I feel more inclined after changing my underpants, I'll return to carry on tomorrow. Fingers crossed.
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Smoggie
Well-Known Member
What a nightmare! It must have taken a lot of amps to do that but I'll keep my fingers crossed that that's all the damage there is. The only way to tell for sure is hook it up with a new cable and see if it works.
If it gives you any inspiration to get stuck back into it, here's a pic from another lunch time flying session today, another three flights undet the belt:
If it gives you any inspiration to get stuck back into it, here's a pic from another lunch time flying session today, another three flights undet the belt:
Heliman450
Well-Known Member
Hi Steve, I'm afraid I don't have a warm fuzzy feeling at the moment. I haven't found anything that leads me to believe that there's any in-built protection from such a short. I can find lots of good stuff regarding how well protected everything is from surges in normal use but that's the least of my worries right now.
Looking on the bright side, I knew there must have been a reason for buying a pack of 5 patch cables
Tomorrow, I'm going ahead with the setup process and as a result, will obviously be doing just what you suggest using a new patch cable. Fingers crossed, hey?
Looking on the bright side, I knew there must have been a reason for buying a pack of 5 patch cables
Tomorrow, I'm going ahead with the setup process and as a result, will obviously be doing just what you suggest using a new patch cable. Fingers crossed, hey?
Heliman450
Well-Known Member
Hi all,
At the moment, it's looking like bad news and with it being Sunday, I'm a bit stuck to move forward by getting hold of anyone. I put my query to Bavarian Demon but don't expect anything back until tomorrow at the earliest. The Rx. is bound to the Tx. but I suspect that the ESC is damaged as it just sits there flashing away merrily during the initialisation. I checked out the ESC using the programming interface but that seems to also draw a blank as shown in photo #1 below.
#1
#2
I'm going to check out the documents and see if I can create a single one that doesn't have all the Chinese writing in it and locate a replacement ESC, just in case that's the problem
At the moment, it's looking like bad news and with it being Sunday, I'm a bit stuck to move forward by getting hold of anyone. I put my query to Bavarian Demon but don't expect anything back until tomorrow at the earliest. The Rx. is bound to the Tx. but I suspect that the ESC is damaged as it just sits there flashing away merrily during the initialisation. I checked out the ESC using the programming interface but that seems to also draw a blank as shown in photo #1 below.
#1
#2I'm going to check out the documents and see if I can create a single one that doesn't have all the Chinese writing in it and locate a replacement ESC, just in case that's the problem
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Smoggie
Well-Known Member
Phil,
The ESC shouldn't have been damaged, it's the FBL or receiver that I'd be worried about. I can see in the photo that the reason the programming box isn't recognising the ESC is because you havent got the ESC powered. You need to connect a battery to the main power input wires (a single 6S battery will do it doesnt have to be 12S). You also dont need the seperate power supply to the programming box, the box will get the power it needs from the BEC in the ESC. The seperate power supply on the box is only for use with ESC's that have no BEC.
If the ESC is beeping constantly then that means it's not receiving a closed throttle signal. That could conceivably indicate a Rx/FBL fault due to the shorting but equally it may just mean that you need to calibrate the throttle range or that the throttle lead for the ESC is plugged into the wrong port on the FBL. It's not unusual to have a beeping ESC on first power up.
Hope this helps.
Steve
The ESC shouldn't have been damaged, it's the FBL or receiver that I'd be worried about. I can see in the photo that the reason the programming box isn't recognising the ESC is because you havent got the ESC powered. You need to connect a battery to the main power input wires (a single 6S battery will do it doesnt have to be 12S). You also dont need the seperate power supply to the programming box, the box will get the power it needs from the BEC in the ESC. The seperate power supply on the box is only for use with ESC's that have no BEC.
If the ESC is beeping constantly then that means it's not receiving a closed throttle signal. That could conceivably indicate a Rx/FBL fault due to the shorting but equally it may just mean that you need to calibrate the throttle range or that the throttle lead for the ESC is plugged into the wrong port on the FBL. It's not unusual to have a beeping ESC on first power up.
Hope this helps.
Steve
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Heliman450
Well-Known Member
Hi Steve, I'm going through a mini-crisis at the moment.
The photo I included below was one I made quickly yesterday just before leaving for the day not thinking about the flight batteries. I went through so many variations yesterday that I had to just stop what I was doing and leave well alone. I can't remember if I tried a combination with it powered up. I sat down early this morning and entered my feedback mentioning my intention to check out the documents only to find that I'd left my memory stick behind with the files I need
I don't have the car today so was just thinking that if I make the journey with public transport, I need to do something differently to make it worthwhile and move forward. It only takes about 35 mins to get there but I was just about to say 'stuff it'
get a few beers from the cellar and watch the last race of the F1 year later today. Thanks for your input, it'll help if I decide to go to my workshop.Cheers
Smoggie
Well-Known Member
ESC aside did you try setting up the FBL? That's the first thing i'd be trying, wire it all up, hook the FBL up to your PC and see if the FBL, receiver and servos seem to be working correctly.
If it's not working then try it with the servos connected direct to the receiver... it's basically a process of elimination, you can use 'known good' parts from your 550 to narrow down the problem, if there is a problem.
If it's not working then try it with the servos connected direct to the receiver... it's basically a process of elimination, you can use 'known good' parts from your 550 to narrow down the problem, if there is a problem.
Heliman450
Well-Known Member
Hi Steve,
I just returned from my workshop with the memory stick, beers are pre-cooling in the freezer. I was able to go through the ESC programming and have recorded what's programmed.. The diagram that came with the ASBOX doesn't show using the heli battery to power the system, only the separate battery as I was trying. The one that shows it that way is in the ESC manual on page 4 . I took my 550 to the workshop yesterday for exactly the reason you suggest but I'm inclined to use only the 700 stuff until I can't think of anything else.
First step for me will be sorting out the different instructions into one (hopefully) reliable version to work with, then back to the workshop tomorrow to work through everything logically as I should have done first off.
Thanks again for the tips.
Smoggie
Well-Known Member
If you download the Hobbywing PC software you can connect the ESC to your PC and update it's firmware. It's a worthwhile update because it adds a new option to adjust the initial start up power: https://cdn.shopify.com/s/files/1/0109/9702/files/Hobbywing_USB_Link_V4.0.3.zip?816210359424584430