My My what have we here TP 4070-CM

[donhuff]

4070-CMs 2200 and 3200 kv

I was going to take one apart to see if I could tell the difference between these, and the older 4070s that I have. But there is no need as it's easy to see from the outside. The air cooling holes are totally useless, because they are plugged up with COPPER! The white is a piece of paper insulation to keep the wire from rubbing on the end bell. The copper is pushing up against the paper.


Hopefully I'll be able to try them out before to long. I have to get a decent speed controller first though, as I do not think that my seaking 180 will let me use them to their fullest LOL.



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[Lone-Wolf]

I've got two of the 2200Kv's on their way in the mail right now! Hmm, paper in the endbells, doesn't sound to good. I'll be using mine with some new MGM's good for 280amps in my dual Cheetah, will report in on how these motors do and looking forward to your results as well.

[donhuff]

I don't know that the paper blocking the holes is really a bad thing. Just means that there wont be any way for air to move through it. But it does mean that you better have the water cooling jacket working well. They sent me a couple of their jackets with these motors, but they are the same short one they send with all their motors. I don't use them but instead make my own, and I make them as long as possible to get as much cooling as I can.

I bet the paper is there because they made the stator a little longer, and that's why the copper comes all the way to the back end. Ya know usually, there is a good bit of wasted space back there. I was wondering how they got another 1500 watts out of the same sized motor. Making the stator, and possibly the rotor, longer would explain it.

I'm gonna have to take one apart and find out!

[Lone-Wolf]

I just worry what will happen to the paper once it inevitably gets wet, wonder why they didn't use some thin plastic instead, may have to do this mod.

At any rate will be an interesting motor to run especially for SAW and won't have to worry as much about the motor grenading when in the high 40K rpms as with all other TP's!

[srislash]

Holy packed in a can BATMAN!!! Yes brace yourself ESC!!! I had a an old pair at 2200 and they were warming the SK 180's.

LoneWolf, what is this grenadine all other TP's?
I'm in my third year on these https://youtu.be/X2LykA7azQA

[Lone-Wolf]

Well I don't speak from experience when it comes to ruined TP's at high rpm but I have read about it in several places/threads and something to be mindful especially in the longer cans with 5mm shafts. Yeah my 4050 2100Kv's are holding up fine on 6S in a smaller boat but the extra headroom rpm-wise of these new higher rpm motors will be a little less un-nerving when constantly pulling the trigger.

[srislash]

Well I don't speak from experience when it comes to ruined TP's at high rpm but I have read about it in several places/threads and something to be mindful especially in the longer cans with 5mm shafts. Yeah my 4050 2100Kv's are holding up fine on 6S in a smaller boat but the extra headroom rpm-wise of these new higher rpm motors will be a little less un-nerving when constantly pulling the trigger.

Yes any kind of rpm is a lot to expect from a long 5mm shaft twanging around in there.
So two of these in the 'Already a Beast' Cheetah, mmm...

[Lone-Wolf]

Yeah buddy, I didn't want to let the cat out of the bag (pun intended) yet until I reach triple digits...I just couldn't resist but seemed the next logical step. Let's pray she holds together.

Sorry to hijack the thread!

[donhuff]

Well, the shaft is NOT 5mm all the way. Only the section that sticks out past the front bearing. Through the bearings and to the edge of the magnets, it is 8mm. Then where the magnets are glued on, there is a steel sleeve(?) pressed on the shaft and it appears to be around 12mm diameter. This should greatly strengthen the shaft right where it needs it most. So there is a lot more "meat" to the shaft than just a tiny 5mm rod.

My other 4070 motors have an 8mm shaft all the way. The advertisement that I saw for these new motors lead me to think that they were only offered with the 5mm shaft. Later I saw where you could order them either way, 5 or 8mm.

I actually prefer the smaller shaft so that I can use a smaller coupler. I do not like having such a large out of balance coupler on there, like is required with the larger shaft. Especially at such high RPM.

At what point (power wise) do FE boats go to a 1/4" flex shaft? I'm mostly a gas guy, and with our big boats and huge props (compared to FE props) we would be afraid to even try a 3/16 shaft. And some of the FE motors that we're using are rated to have way more horsepower than what is possible with the strongest gas motors.

This is an AQ 2030 rotor that tried to "throw" some of its magnets off, after 5 years of use in a p limited hydro.

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[srislash]

Myself I would consider 1/4" flex on any heavier size boat running 50mm or greater props, ie: I have a R-42 with twin 1717's in it and I went 1/4". 1727 are healthy sized and I run 6s4p in it.

As far as rpm and couplers, go with MBP ones and don't worry.

Shawn

[donhuff]

I couldn't stand it any longer, so I opened one of them.

Now I'm even more confused! No segmented magnets??? The rotor is a little longer than the older version by .070". I don't think that's enough of a difference to matter. I couldn't get in there good enough to measure the stators, but they looked the same. The rotor IS .010" larger in diameter than the old one.

And I was wrong about the wire going all the way to the back end bell. It appears to be the same as the older motors. But the paper (or whatever it is) is glued on the inside of the end bell for no other purpose than to cover up the air holes??? Same as with the forward end bell in the picture. That's a thin sheet of G10 glued on there, again to plug up the holes. The bundles of wire coming out the back sure looks bigger on the new 3D motor, but after measuring it and my older 3Y motors, they measure the same. I guess the increase in weight all comes from the different magnet design.

[donhuff]

Oh, ok.

I've not run a prop that big yet. I have run a 1915 a little to see what it would do, and yes it was fast. But then I dropped back to a 1714-1715 for racing.

And all my motors are 36 and 40mm diameter. I have not tried a "big one" yet. These TP4070 motors are strong but I don't think that I'm using near half of what they are capable of, since my seaking 180s never have a problem keeping up so.

[Lone-Wolf]

For what it's worth, I lost a nice X457 prop when the 3/16th stub just snapped off, it was pushing hard at over 40K rpms and in a 54" Cat, I would never use a 3/16th shaft in a heavy boat anymore. I have had no problems running larger props like X457 etc on my 40" and 46" Deep-V with 3/16 stubshafts. I do run 1/4" cable on both, running a TP5670 in both. Only problem with 1/4" stubs is the prop selection is not great. A .187 cable is perfect I think for 4050 and 4070 motors with up to 50mm props.

[srislash]

For what it's worth, I lost a nice X457 prop when the 3/16th stub just snapped off, it was pushing hard at over 40K rpms and in a 54" Cat, I would never use a 3/16th shaft in a heavy boat anymore. I have had no problems running larger props like X457 etc on my 40" and 46" Deep-V with 3/16 stubshafts. I do run 1/4" cable on both, running a TP5670 in both. Only problem with 1/4" stubs is the prop selection is not great. A .187 cable is perfect I think for 4050 and 4070 motors with up to 50mm props.

That was a 1/5" shaft stepped down to 3/16" was it not Steve? I will talk to you in email on thoughts on this in a bit.

I wonder why the closing of the end bells?

[srislash]

Oh and about the magnets? Are they solid or two piece like LMT?