If you have a magnetic prop balancer, it is very easy to balance DT750 bells. I had to rig mine to get the magnets closer but I sharpened a tip on the end of the motor shaft by chucking the bell with the shaft in my cordless drill, took my angle grinder with a flap wheel and had a pointy tip in a matter of seconds. Put the tip on the magnet of the balancer and let the other side float in the magnetic field, then just use tape to balance them like props. Works like a charm! No guessing with iphone apps here. Stable flight take precision tuning, don't skimp out!

Originally Posted by subaru4wd

Thanks. You are right about them looking cleaner than 4mm shafts and a few locknuts. Is there a 4mm shaft that works with these motors? Or do I have to cut & modify one? I didn't find one when I was searching last night. I have a couple vices, so im not worried about the work. Plus i could use a quicker method of swapping out props.

I was looking at using this prop adapter: http://www.hobbyking.com/hobbyking/s..._Type_4MM.html

Now I just have to figure out which 11x4.7 prop will be best.

I've had really good luck with RCTimer. They have the adapters for a buck and free shipping:

http://www.rctimer.com/index.php?gOo...1&productname=

Here's the shaft:

http://www.rctimer.com/index.php?gOo...8&productname=

And while you're at it, you may as well get some of these:

http://www.rctimer.com/index.php?gOo...1&productname=

If you're feeling intrepid, you can just buy some 4mm drill rod and roll your own. Here's an article on doing that:

http://www.rcgroups.com/forums/showthread.php?t=1240725

The only caveat is that you'll have to grind the little flat on the shaft for the grub screw in the motor bell, but if you're up to the rest of this, that shouldn't be much of a stretch.

Lastly, for more than you ever wanted to know about DT750 motors, here's a cool, long thread:

http://www.rcgroups.com/forums/showthread.php?t=777998

Mostly about rewinding, but there's lots of other interesting stuff in there, including info on where to get bearings should you need to replace them.

Brushless motors are really interesting- they can be kept running forever by replacing certain key parts. Unless you kill one badly by crashing hard on it. But we don't do that, do we?

Rick

PS- Good props at RCTimer also. NFI- I just like them.

I've heard there is an eflite part # for the bearings. I think the coaxial helis like te CX3 use the same bearing for the mainshaft that the DT750s use.

I bought these bearings when I bought all my other stuff: http://www.hobbyking.com/hobbyking/s...dProduct=11521

They worked perfectly for my new DT750. Thanks for those links 2400RDR, i have been looking for some place that competes with HK on prices, and the free shipping is a bonus too But I looked and didn't see any props in the 11x4.7 size. Which props are you using on your DT750's??

Originally Posted by WhiteFox50

I've heard there is an eflite part # for the bearings. I think the coaxial helis like te CX3 use the same bearing for the mainshaft that the DT750s use.

They can also be found at all different price points on ebay by searching "4x 7 x 2.5mm bearing". I think that size bearing is also used in Traxxis trucks, so it may be possible to find them in your LHS, albeit probably at highly inflated prices.

I think I read somewhere that it's usually the upper (or outer, depending on how you have the motor mounted) bearing that goes out, so replacing just one bearing might do it for a noisy motor.

Originally Posted by subaru4wd

I bought these bearings when I bought all my other stuff: http://www.hobbyking.com/hobbyking/s...dProduct=11521

They worked perfectly for my new DT750. Thanks for those links 2400RDR, i have been looking for some place that competes with HK on prices, and the free shipping is a bonus too But I looked and didn't see any props in the 11x4.7 size. Which props are you using on your DT750's??

Just now, if I needed any props, I'd buy them right here on RCG from one of our brothers:

http://www.rcgroups.com/forums/showthread.php?t=1719446

A friend of mine bought some from him and said the service was great. Cheap shipping too.

Rick

One other benefit I forgot to mention about those prop adapters is that the mounting shaft for the prop is 6 mm, which makes it a perfect fit for the GemFan props that most of us use. No need to futz around with those little plastic adapter rings.

Rick

Thats what im thinking. Im tired of drilling 4mm holes into my props, and hoping they are centered.

I just took advantage of the free shipping on the shafts & prop adapters... got 3 of each comming.

The DT700 and DT750 are great motors but there are some great alternatives without the hassle. personally I have had great success with the RCTimer 2836 series motor without having to change the shaft or balancing them.. But lets not get into a flaming battle over which is better, what ever works best for the given scatchbuild.

Back on topic, here is a quad I am building for acrobatic flight. I made the frame out of Lexan which is really really tough stuff, and aluminum framing I found at work that was part of a sliding cabinet door of some sort. It has a nice channel on the bottom that the doors would slide in. I really like it because it strengthens the arms. I milled the ends down in a Bridgeport so I could mount it within the lexan, and also for the motors. Just the frame with no electronics weighs 346g. Not too bad, it's pretty light to me, hope it works good!

I just need to order motors, which just went out of stock

Nice- keep us posted on your progress.

Rick

Here are my MWC White Quad

comicflyer mwc whitequad (4 min 24 sec)

and my Bloggie-Copter Y6

Bloggie Copter Y6 (4 min 53 sec)

CU Eddy

Originally Posted by subaru4wd

Thanks. You are right about them looking cleaner than 4mm shafts and a few locknuts. Is there a 4mm shaft that works with these motors? Or do I have to cut & modify one? I didn't find one when I was searching last night. I have a couple vices, so im not worried about the work. Plus i could use a quicker method of swapping out props.

I was looking at using this prop adapter: http://www.hobbyking.com/hobbyking/s..._Type_4MM.html

Now I just have to figure out which 11x4.7 prop will be best.

I got my prop adapters off of ebay. It was around five dollars for five prop adapters. not a bad price, though HK's shipping might be better.

i used that link to rctimers page and got the three adapters and 4mm shafts and got free shipping. grand total was $6.60.

Hi, was told I should post here.
My intro thread is here: http://www.rcgroups.com/forums/showthread.php?t=1722381

video:

Tricopter v2.5 beer lift payload test & acro flying (3 min 26 sec)

pics: