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2.4G Spektrum Radios Spektrum 2.4 Gigahertz Radios and Technology


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Old 11-28-2007, 11:32 PM   #1
G-Force Heli
 

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Default Quad bearing upgrade for the DX7 gimbals by G-Force

For some time now the gimbals on my DX7 seem worn out and I have noticed some play. So I opened up the radio to check the tension springs. To my discovery, each gimbal only had a single ball bearing and a bronze bushing supporting it.

I have since replace all four bronze bushings with ball bearings. The radio now has quad bearings for each stick, two ball bearings for each axis.

It took me at least half an hour for each gimbal to be taken apart and reassembled. If you decide to do this, work very slow and carefully. There are a lot of wires to be aware of and don’t lose any screws or springs during the process.

All I can say is; it’s amazing how the sticks on the DX7 now feel more precise and smoother than it was new.

Garf
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Last edited by G-Force Heli; 11-29-2007 at 12:51 AM..
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Old 11-28-2007, 11:54 PM   #2
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Nice, may have to try this someday. Got a bearing size for us? (OD x ID x Width)

Thanks for the info,

-Fog
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Old 11-29-2007, 11:42 AM   #3
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Bearing part numbers would be nice
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Old 11-29-2007, 11:52 AM   #4
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Curious as to how long you had been using the TX for when the slop started to develop?
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Old 11-29-2007, 12:17 PM   #5
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where did you get the bearings from?
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Old 11-30-2007, 04:01 PM   #6
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Cool Bearings/

I guess I'm going to have to break out the Micrometer tonight and work on that.
I have dang near ever size bearing out there with as many crashes as I've had in my first 5 months of flight.
I'm sure I can get something to work out.
I had a bad orientation problem last night,, But I guess that's good,, 30 flights and one Unplanned landing. :o
It was kinda dark out. Heli was about 100 feet away I though it was coming down Head first, when I moved the stick in what I though was the right way, I was very dissappointed 3 seconds later.
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Old 11-30-2007, 08:31 PM   #7
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The radio is a year old and gets heavy usage almost everyday. The sticks always felt loose since it was new. The bushing fit very loose on the gimbals so there no friction on the gimbals. The bearings fit snug onto the gimbals but are very smooth in operation, you can feel the difference.

Garf

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Originally Posted by flyboy320 View Post
Curious as to how long you had been using the TX for when the slop started to develop?
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Old 11-30-2007, 08:37 PM   #8
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I am not here to solicit but to tell you all that the quad bearing gimbals are the way to go.

My HF id gives it away who we are.

Garf


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where did you get the bearings from?
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Old 11-30-2007, 08:42 PM   #9
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Quote:
Originally Posted by G-Force Heli View Post
I am not here to solicit but to tell you all that the quad bearing gimbals are the way to go.

My HF id gives it away who we are.

Garf
Are you implying you'll be selling a set of bearings for this purpose?

Thanks,
John
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Old 11-30-2007, 08:50 PM   #10
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John,

I am here to share with everyone my discovery how well the quad bearing upgrade works on the DX7. Keep in mind this has to be the most popular radio on the planet by now.

This simple upgrade is probably the best thing you can do for the DX7.

The bearings can be bought from any hobby store. We are not a hobby store.

Garf



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Are you implying you'll be selling a set of bearings for this purpose?

Thanks,
John
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Old 11-30-2007, 09:16 PM   #11
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Quote:
Originally Posted by G-Force Heli View Post
John,

I am here to share with everyone my discovery how well the quad bearing upgrade works on the DX7. Keep in mind this has to be the most popular radio on the planet by now.

This simple upgrade is probably the best thing you can do for the DX7.

The bearings can be bought from any hobby store. We are not a hobby store.

Garf
Understood, although you must not know how awful hobby stores are around the Denver area for random parts like bearings

Any chance at all you could share the bearing size used so we can all go find some?

Thank you,
John
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Old 11-30-2007, 09:22 PM   #12
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The bearing size is M4 x 7 x 2mm . I am sure any store selling micro helis would have this size. Some ball bearing servos use this size.

Garf



Quote:
Originally Posted by th3tick View Post
Understood, although you must not know how awful hobby stores are around the Denver area for random parts like bearings

Any chance at all you could share the bearing size used so we can all go find some?

Thank you,
John

Last edited by G-Force Heli; 12-02-2007 at 08:39 PM..
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Old 11-30-2007, 10:01 PM   #13
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M4x7x2 is kind of a weird size. M4x7x2.5mm is the trex 600 flybar seesaw bearing is it too wide to fit?
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Old 12-01-2007, 06:54 AM   #14
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Has anyone found out the correct bearing size/part number needed yet?
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Old 12-01-2007, 08:14 AM   #15
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Quote:
Quad bearing upgrade for the DX7 gimbals by G-Force


Would G-Force be marketing those in a complete set with step by step instructions to do the conversion? I would buy such a set without thinking.
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Old 12-01-2007, 02:25 PM   #16
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http://www.vxb.com/Merchant2/merchan...egory_Code=4mm


abec 3's 6 bucks each,just ordered 2
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Old 12-01-2007, 03:00 PM   #17
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I see those are 4x7x2 bearings. My local HS has 4x7x2.5 size ones for half that price. Anyone know if they would fit?
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Old 12-01-2007, 03:02 PM   #18
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Those are open. I haven't found a source for a sealed 4x7x2's yet. I might try the 4x7x2.5 the next time my Trex head is apart.
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Old 12-01-2007, 03:12 PM   #19
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its inside your radio a sealed clean environment,sealed vs open makes no differance in this application.
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Old 12-01-2007, 07:45 PM   #20
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The 4x7x2 open bearing is fine. That is what I used.

The other ball bearing that is on the gimbals are also open.
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