[Dutkoski]

Hi guys, got a slight problem. The Dr Mad Thrust motors for the 70 mm EDF's has a 29 mm diameter housing. The Change Sun and most other EDF units have a 28 mm diameter shroud. Has anyone had any success turning down the motor housing down to fit. I think the wall thickness is able to loos a mm but before I attempt this, just wanted to know if anyone has any other suggestions.

[SARPLT]

John
If it is the 10 blade CS fan that you are describing you won't have any luck getting the Dr Mad motors to fit. I having been running the HK 6 blade 70mm fans ($6) mated to the Dr Mad 2600kv in my SU 35 and BAE Hawk with great success. Although the HK ad says this fan will take a 28mm motor, the Dr Mad motor (29mm) fits nicely with no modifications. So I figured that I would try the CS fan with a Dr Mad 2200kv motor for comparison but no luck as the opening in the CS fan is a true 28mm. I tried sanding out the fan housing and taking the finish off of the motor but it is still too big to fit.

Marty

[Dutkoski]

Well, not wanting to damage the motor, and since I have over 30 CS EDF's, I very carefully ground away the opening in the fan shroud with my dremel and Dura Grit 60 grit 1/2" sanding drum. I finally got the motor in but not much plastic left at the base of the staters. It's a fairly tight fit, I might rough up the motor case with the grinder and apply some JP weld epoxy where the staters are. Basically, make it all one piece.

How does the six bladed fan sound? I have a bunch of them at home, maybe the Change Sun impeller will fit in it, really looking for the turbine sound.

[SARPLT]

Wow I can't believe you got it to fit. There can't be much material left. I would stand back the first time you run it up with fear of it coming apart. After I started sanding my CS 10 blade fan shroud I found it to be very flimsy so I gave up trying to make the motor fit. The 6 blade fan does not have the nice turbine sound of the higher blade count fans but it is not too whinny. Considering I am getting over 4 lbs of thrust from this setup you can't beat the price ($42 US) for this much performance. I have not looked at trying to put the CS 10 impeller in this fan housing.

Marty

[Dutkoski]

On X-Flight's website, they are selling a 70 mm EDF, by XRP, it has a 14 bladed impeller and will fit motors up to 30 mm in diameter and at just under $19.00 USD looks very appealing. Think I'll order a bunch to try out.

[Dutkoski]

Well, the motor is in, the impeller is balanced, all that is left is to make a test stand and fire it up. Just received with the two motors, a brand new Turnigy 4000 mah 6 cell battery, so will charge it up and see how it goes.
Of course, the 100 amp ESC's haven't arrived yet, so will test them with a Turnigy 80 amp Plush ESC and be careful not to over do it.

[4stripes]

Is it not possible to use the 6blade housings with the 12 blade rotor?
I don't know the diameters of both to compare...
The L2855 2800kv out runner 10 blade combo I used in a friends vampire flies great on 4s. Super sound too.
Perfect 4s setup IMHO.

[Dutkoski]

Maybe, but I don't have a 6 bladed setup with me. Going to give this setup a go to see what takes place. Figure I'll use some thin CA to wick between the shroud and the motor casing, but it's really a tight fit. The whole assembly feels quite firm, who knows, it might work.