25 mm info

[flyerdude81]

I'm starting to consider making a 25 mm stator motor. It's great to see that I can get insulated stators, but I have a problem understanding how to get the motor completed. I note that the center opening on these stators is too large to use the bearing tubes I have used so successfully for the 22.7 mm motors. Do I have to scrounge a precision tube from somewhere, or am I missing something on the site? Without some way to hold the shaft, it's going to be pretty difficult to make a functional motor!

Also, how the heck do you use the GBx flux ring for a 25 mm stator? The indication is that one can solder it to the 25 mm can. How does one ensure it's straight? Pressing to the GBx bell is straightforward, and the machining guarantees alignment.

I just would like to have more information about what is possible, and what I shouldn't tackle without sophisticated tools. Thanks for any information you can share with a relative newbie!

[EddieB]

You can get a bearing tube that fits the 25mm stators from strong rc motors.

Using 5x4x1 magnets in the GBx1 FR did not appear to be the correct answer, but they do fit in the std. 25mm can. Engineering concepts might have thinner magnets to try though.

I don't know the answers to the rest of your questions as my 25mm efforts in general so far have been less than successful. :( The 22.7mm GBx stuff OTOH is very fun to work with so that is where I am playing right now. :)

Other folks with better tools appear to be having some 25mm successes though, as there are 25mm motors in the database.

EB

[LBMiller5]

As it stands right now, if you want to play with the 25mm stuff, you had better own a lathe because the stock 25mm cans are too thin to really make motors from, which means you have to make your own flux rings from steel tube stock.

I have a bunch of 25mm stators that I got from the GB site, and I plan on making some custom motors with them.

I have heard rumors that Steve is working on a line of 25mm GBx type parts to make larger motors, so when that becomes available, pre-made parts can be purchased to make the larger motors.

Lucien

[swatson144]

I am having great success with 25mm motors (well I consider it successfull). Everything but the stators are custom made which makes it very time consuming. In a nut shell...If you don't own a lathe you won't get far in building them, until the gb25 parts come out.

[flyerdude81]

Thanks for all your information, guys! Since I don't have access to a lathe, I guess I'll just have to wait on building a 25 mm motor.

How about larger diameter outrunners? Is there a source for anything even nearly approximating the quality of the 22.7 mm stuff we can get from Steve? It's not that I'm not really happy with this stuff -- It's just that I can see the benefit of powering bigger, heavier planes with brushless motors, and I don't want to spend my kids' inheritance doing it.

Again, thanks so much for your notes!

[Air Mover]

You can use a file on the mags .. bevel the edges to sit the .9mm mag down flush with the gbx flux ring.. not the greatest but does work.... rather have 2mm thick mags in a 29.8 ID flux ring.. hint hint :wink:

[Q]

careful with that!! Mags are coated because the inside is toxic. If you really need to file the mags wear a mask and coat them again!!

[Air Mover]

Yes agreed .. I knock off the corners and when I glue them an they seal back up..

Guys very good new KOMODO Hobbies.com is selling working bells for the 25mm stators you can drop in 5X5X1mm N50 mags.. there bells are on sale today 4.98 per bell awesome buy.. appears tobe reduction in price for good not sure. :D

http://www.rcgroups.com/forums/showthread.php?p=3473097#post3473097

Read up on this thread for 25mm stators and Komodo bells..
http://www.rcgroups.com/forums/showthread.php?t=348109

[Air Mover]

Sorry Steve I dont like spreading the news like this but we need bells for the 25mm stators .. hope your working on a solution on your end.. as I would rather have bells to fit 2mm mags.. Steve you dah man dont worry we are the faithful. 8)

[Air Mover]

Another item im looking forward too is working with your large 9pole 25mm stators.. there is room for much larger wire gage for very hot high rpm motors. The hard enamel coating can handle alot of heat compared to the nylon covers over the 20mm stators.

[Mike3976]

Wondering if there is any new news concerning the development of 25mm bells? I,ve got a pair of diy Microdans which are great! but there's room for improvment in the design. Would really like to see 25mm bells to fit a single 25mm stator, a tripple stator, and a 5 stator stack. Not asking for too much, am I!!!

[ScubaSteve]

What kinda improvements? :wink:

[spoke2570]

Mr George at http://www.engconcepts.net/ has some 6x2x1 magnets that calc out to a .12mm airgap in a std GBx can. I have some and will be doing a 12mm stator stack as soon as time allows.

pete b