700 My T-Rex 700X Build
- Thread starter Heliman450
- Start date
PLANETGETLOW
Banned
I pick my 700 up soon. Cannot wait. It's an older gen but has some great bling on it!!
Smoggie
Well-Known Member
Seems like everyone is getting new helis which doesn't help me fight off the urge to buy another heli that I don't really need!
A guy on one of the UK forums is actually selling a Trex 700X which he has built but only flown a few times, the heli cant be more than a few weeks old because they have only been available a few weeks. He was selling it as an airframe with motor and ESC (i.e. without servos or blades or FBL) and the price seems pretty good. Trouble is that by the time I add in the cost of decent servos and blades and a FBL I'm up to the cost of a brand new Super Combo kit. Not much point buying a used heli (no matter how lightly used) if I can get a new kit for the same price. The new Super Combo kits are such good value I think he'll have a hard time selling his heli.
decisions decisions!
A guy on one of the UK forums is actually selling a Trex 700X which he has built but only flown a few times, the heli cant be more than a few weeks old because they have only been available a few weeks. He was selling it as an airframe with motor and ESC (i.e. without servos or blades or FBL) and the price seems pretty good. Trouble is that by the time I add in the cost of decent servos and blades and a FBL I'm up to the cost of a brand new Super Combo kit. Not much point buying a used heli (no matter how lightly used) if I can get a new kit for the same price. The new Super Combo kits are such good value I think he'll have a hard time selling his heli.
decisions decisions!
Heliman450
Well-Known Member
Hi Steve, seems like a simple decision to me as you already admit to having more than enough helis. My decision to go for the 700X is to give me a second (bigger) option to my 550 until my skills improve. The extra cash involved in a custom-built heli with all the electronics bought separately doesn't make sense to me yet. The Align packages are great value as a package, not so much as a kit (or airframe) and then buy the extra bits. I did that calculation on mine and decided on your recommendation without too much thinking.
Here's my latest plan for the conversion to Supra X connectors. By my calculation, it leaves me with two spare pairs to use on an extra two batteries when I need them. If I get to my target of the Velos-Rotors 880 I'll need at least 8 batteries by then.
View attachment Series Wiring.pdf
What do you think?
Here's my latest plan for the conversion to Supra X connectors. By my calculation, it leaves me with two spare pairs to use on an extra two batteries when I need them. If I get to my target of the Velos-Rotors 880 I'll need at least 8 batteries by then.
View attachment Series Wiring.pdf
What do you think?
Smoggie
Well-Known Member
Phil,
It's a conflict between the rational side of my brain which tells me I have already got too many helis so I don't need another, and the emotional side that tells me I want a new one regardless!
As for the connectors... On the series setup for the 700X you shouldn't need any extensions between the battery and the ESC. The batteries and ESC will connect directly together. Similarly the series link between the two batteries should also be a direct connection without the need for any extension. This will take a few connectors out of the picture.
You may need more charging leads. Charging batteries individually gets very time consuming once you have a few packs. If you have a charger with enough power then parallel charging becomes very attractive. Obviously if you want to charge multiple batteries simultaneously you will need multiple charge leads. I do all my charging in parallel I've got a couple of 8 port parallel boards each one hooked up to an output channel on my iCharger 4010 duo, so a routinely charge 16 batteries in one hit, all done in 20 minutes. This sort of setup would be pretty much essential for the Velos!
It's a conflict between the rational side of my brain which tells me I have already got too many helis so I don't need another, and the emotional side that tells me I want a new one regardless!
As for the connectors... On the series setup for the 700X you shouldn't need any extensions between the battery and the ESC. The batteries and ESC will connect directly together. Similarly the series link between the two batteries should also be a direct connection without the need for any extension. This will take a few connectors out of the picture.
You may need more charging leads. Charging batteries individually gets very time consuming once you have a few packs. If you have a charger with enough power then parallel charging becomes very attractive. Obviously if you want to charge multiple batteries simultaneously you will need multiple charge leads. I do all my charging in parallel I've got a couple of 8 port parallel boards each one hooked up to an output channel on my iCharger 4010 duo, so a routinely charge 16 batteries in one hit, all done in 20 minutes. This sort of setup would be pretty much essential for the Velos!
Heliman450
Well-Known Member
Hi Steve, good luck on that one.
My charging station is more than up to the job of dealing with the batteries so no problem there.
I'm afraid that I can't follow you on the wiring. They must need an interconnection to get them in series and as the wires aren't long enough on each battery there's no other choice.
My charging station is more than up to the job of dealing with the batteries so no problem there.
I'm afraid that I can't follow you on the wiring. They must need an interconnection to get them in series and as the wires aren't long enough on each battery there's no other choice.
Smoggie
Well-Known Member
It's the wire length that i was referring to. I use series connections on several helis, including four helis with tandem mounted batteries similar to your 700X, and have never needed to extend the wires.
You wouldn't normally mount the batteries as you indicate in the diagram. Normally you would have both batteries mounted so that the battery end with the wire outputs faced forward on both batteries. This would eliminate the long runs to reach the rear.
You wouldn't normally mount the batteries as you indicate in the diagram. Normally you would have both batteries mounted so that the battery end with the wire outputs faced forward on both batteries. This would eliminate the long runs to reach the rear.
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Heliman450
Well-Known Member
What connections are you using to the batteries? I'm expecting to make my own up with the Supra X connections.
PLANETGETLOW
Banned
lmao, I have this same problem. Picking up 700 for me personally was along the same thought process. These bigger helis are just so much more stable and fun to fly. I don't have anything (currently) smaller than my HDCell 500.
I got a SMOKIN deal on a 700 that I couldn't pass up, well maintained, and professionally built and flown. The only downside to the bigger helis is flying area. I'm fighting the urge to not buy a smaller one to fly around my yard.
Sorry for the thread derail
Smoggie
Well-Known Member
On the 700 size, 5mm bullets. The Supra X bullets are better because they have a plastic shroud to protect from shorts where plain bullets like I'm using are quite vulnerable to shorts if you get careless for a moment.
jcfernan51
Member
NEED, WANT?? these are thing of the past, now we are ENTITLED to another heli 
Heliman450
Well-Known Member
Hi all, so returning to my thread...................
I'm of the opinion that it's ESSENTIAL to have more than two helis. They should relate to your current skills ( and, yes, needs
). My justification is simple, if you maintain them well and have the skill level so that crashes seldom occur, then the only limitation should be your bank balance and capability to supply them with enough batteries to keep them in the air. The last requirement is your time. I watched an amazing night flight on Facebook, so why not 24/7 
I'm going to start my 700X build on Thursday when my good lady liberates the space for me in our workshop
- - - Updated - - -
Hi Steve, any photos you can publish showing your wiring arrangements and battery charging connections will be much appreciated. I'm holding off buying the Supra X connectors right now until things are a bit more clear for me. I'll probably wait until the air frame is completed before finalising on that.
Regarding the battery mounting............... my thinking is that back-2-back is a better arrangement as neither of the batteries are pressing against the wires but I've never been able to study multi-battery arrangements before other than in diagrams and they never seem to show enough detail.
I'm of the opinion that it's ESSENTIAL to have more than two helis. They should relate to your current skills ( and, yes, needs
). My justification is simple, if you maintain them well and have the skill level so that crashes seldom occur, then the only limitation should be your bank balance and capability to supply them with enough batteries to keep them in the air. The last requirement is your time. I watched an amazing night flight on Facebook, so why not 24/7 I'm going to start my 700X build on Thursday when my good lady liberates the space for me in our workshop
- - - Updated - - -
Hi Steve, any photos you can publish showing your wiring arrangements and battery charging connections will be much appreciated. I'm holding off buying the Supra X connectors right now until things are a bit more clear for me. I'll probably wait until the air frame is completed before finalising on that.
Regarding the battery mounting............... my thinking is that back-2-back is a better arrangement as neither of the batteries are pressing against the wires but I've never been able to study multi-battery arrangements before other than in diagrams and they never seem to show enough detail.
Heliman450
Well-Known Member
Cheers Steve, enjoy your break.
PLANETGETLOW
Banned
I just ordered a 12s Pulse stick for mine.
Heliman450
Well-Known Member
Hi all,
Here are the first pictures of my build featuring the rotor head assembly on page 5 of the instructions. None of my components were glued and were all loose assembled in the factory so the warning to check in the text has some foundation. The only things not glued yet are the feather shaft end screws as they recommend a torque of 20Nm after glueing. My bicycle torque wrench didn't have enough options to extend into the blade holder so I had to raid my tool kit in the basement for the appropriate bits to achieve it.
Here are the first pictures of my build featuring the rotor head assembly on page 5 of the instructions. None of my components were glued and were all loose assembled in the factory so the warning to check in the text has some foundation. The only things not glued yet are the feather shaft end screws as they recommend a torque of 20Nm after glueing. My bicycle torque wrench didn't have enough options to extend into the blade holder so I had to raid my tool kit in the basement for the appropriate bits to achieve it.