Tower Pro MG968 Servo

[Eric0424]

Depends on where you read the specs, I'm seeing MG958 torque range 14 - 20 kg/cm at 6v and transit time range .15 - .19 at 6v. Whichever specs you go by the MG968 is still a little stronger and faster than the MG958.

I can say it's definitely faster and stronger than the Tactic TSX55 (203 oz-in & .21 sec).

[Alonjp]

Yeh I have seen the inconsistency specs for the 958.
From my experience it feels like >20kg servo.
Can't compare it to 968 because I don't have one, but if someone volunteers to send me one I will be happy to test it... ;)

[Eric0424]

Originally Posted by 84yoda

For sure, locked up offered to tap mine but ill most likely do it my self. Picked up M3x0.5 as well.

My tap and drills arrived yesterday and I was able to get the output shaft tapped M3, but it wasn't as smooth as it should have been. The tap and drill were wanting to seize up, so progress was slow as I was removing and cleaning the hole, drill bit and taps often.

Wasn't sure what the problem was, I was using a new drill and taps (tapered & plug) and plenty of cutting fluid. Then I read the words "titanium gears" in the description linked below while checking the specs on the MG958 and MG968 at towerpro.com.tw.

MG968 (Digital Titanium gear high torque) | Tower Pro

I believe these below are updated specs on the MG958 as well, the newer 958 has aluminum gears where the previous model had brass and I'm guessing other changes were made. Since the servo was updated recently it may be why we're seeing a discrepancy in the specs.

MG958 | Tower Pro

[Wade]

I received mine a few weeks ago, but haven't had the chance to try it out, the crappy thing is when I went to put on a servo saver for my monster truck build I found out the screw/hole is stripped. So I guess I will epoxy it and see if that works.

Cheers
Wade

[Eric0424]

Originally Posted by Wade

I received mine a few weeks ago, but haven't had the chance to try it out, the crappy thing is when I went to put on a servo saver for my monster truck build I found out the screw/hole is stripped. So I guess I will epoxy it and see if that works.

Cheers
Wade

Between you, me and 84yota that's 2 out of 4 with stripped threads. I'm not liking those odds especially with 2 more on the way from China. If the epoxy doesn't work, I would recommend a 2.5mm cobalt drill bit and M3 x 0.5 TiN coated taps (1 starting tap & 1 plug tap). Had I known I was working on titanium I would have bought them from the start.

[Alonjp]

Thanks for the link to their website, for some reason I couldn't find it with Google..
I have the newer 958 with apparently Aluminium gear.
The gear threads and all are just fine.
On the other hand, Aluminium T6 is too soft for my taste..
I will rather have a SS instead but no one asked me..

On that perspective the new 968 have a big selling point over the 958 (titanium gear), but the thread issues are a big bummer!

[84yoda]

Originally Posted by Eric0424

My tap and drills arrived yesterday and I was able to get the output shaft tapped M3, but it wasn't as smooth as it should have been. The tap and drill were wanting to seize up, so progress was slow as I was removing and cleaning the hole, drill bit and taps often.

Wasn't sure what the problem was, I was using a new drill and taps (tapered & plug) and plenty of cutting fluid.

How did you hold the gear to drill and tap it? Is it all good now with M3 threads?

Sounds like I may just take up locked up offer and let them do it.

[Eric0424]

Originally Posted by 84yoda

How did you hold the gear to drill and tap it? Is it all good now with M3 threads?

Sounds like I may just take up locked up offer and let them do it.

I removed the output shaft from the servo, then used the 24t Axial aluminum servo horn to hold the output in one hand while I slowly drilled and tapped with my pin vice and Craftsman tap handle with the other hand. I tightened the center horn screw down and tightened the clamp screws, then removed the center screw so I could work.

If they're willing to do it at little to no cost to you, that may be the best option. If you break a tap off in the output shaft that's the end of the shaft.

M3 x 10mm screws thread in perfect now, I'm using Axial AXA0109 oversized head screws (Wraith servo mounting screws) and switched to Ofna servo horns both front and rear.

[svt923]

For those that have stripped output shaft threads, are you using the provided screw? I tried the included screw at first and was able to pull it out with my hand rather easily so I thought I had a stripped output too. Then I tried a M2.6x8 screw like Hitec uses and it screwed in tight with no play and doesn't pull out.

TowerHobbies.com | HPI Racing Cap Head Screw M2.6x8 (12)

You might want to try an M2.6 screw before the drilling and tapping route because its quick, easy, and cheap. If that doesn't work, then proceed with the tapping to M3.

[84yoda]

My other one that isnt stripped uses M2.5. Ill try M2.6 before I send it off or tap it myself.

[Wade]

Originally Posted by svt923

For those that have stripped output shaft threads, are you using the provided screw? I tried the included screw at first and was able to pull it out with my hand rather easily so I thought I had a stripped output too. Then I tried a M2.6x8 screw like Hitec uses and it screwed in tight with no play and doesn't pull out.

TowerHobbies.com | HPI Racing Cap Head Screw M2.6x8 (12)

You might want to try an M2.6 screw before the drilling and tapping route because its quick, easy, and cheap. If that doesn't work, then proceed with the tapping to M3.

good call, I havent given that a try. It is exactly as you stated, I can pull the screw straight out by hand. Thanks for the heads up.

Cheers,
Wade

[84yoda]

Eric0424, did you get the 968 servo's from china yet?

[Eric0424]

Originally Posted by 84yoda

Eric0424, did you get the 968 servo's from china yet?

Not yet, they left New Jersey on the 8th, but I've had trouble getting stuff from the east coast recently. Shouldn't take more than one or two business days to reach my state from New York, New Jersey or Pennsylvania, unfortunately the USPS has been a little slow this year. From Hong Kong to the US and even processing through the US Customs facility (ISC New York) was pretty quick.

[84yoda]

Ya there's something wrong with usps, package I ordered says its in San Francisco, Ca still and it just showed up. So no one scanned it, and thats how packages get lost too.

[Eric0424]

Servos finally made it in today. Both are identical to the Locked-Up servo inside and out, same 24 tooth output shaft with M2.5 thread, titanium gears, same circuit board and motor. Neither of the output shafts were stripped so that's a plus, but they'll be getting drilled & tapped M3x0.5 anyway. Seems these were well worth the $56 I paid, looks like they've gone up about $8 recently though and they're still out of stock at Locked-Up RC.

T Pro Digital Servo MG968 High Torque 24kg Twin Set | eBay

[84yoda]

What gears inside are titanium? Or just the output shaft is titanium?

How long did it end up taking to get to you?

[Eric0424]

I can't be 100% sure on all the gears, but they all look like titanium. Total time to get them was 15 days, my order was placed on 07/30 and they got hear on 08/14. Would have been 3-5 days faster if the USPS had not dropped the ball.

[winner]

for cheap i'll stick to my $20 Solar D772 from hobbypartz. 417oz and never had one go bad on me.

[Eric0424]

Originally Posted by winner

for cheap i'll stick to my $20 Solar D772 from hobbypartz. 417oz and never had one go bad on me.

368 oz-in/0.20-sec. @ 6v, 417 oz-in/0.17 sec is @ 7.4v. Although some are not getting the published torque specs from their D772's, for a $22+ servo anything over 300 oz-in should be considered acceptable if it's getting the job done. Reoccurring reports on overrated torque/speed specs, glitching, heating and centering issues have kept me from buying Solar in the past. If the Tower Pro holds up I see no reason to change that since the MG968 is a good cheap/budget servo.

I gave the Tower Pro a shot because I don't mind supporting a few of the vendors here and I was ready to start the rear-steer conversion on the Wraith. So I was looking for a servo in the 250-350 oz-in range when Locked-Up posted their sale.

Tower Pro has the digital, high-voltage MG959, a little faster (at 6v) and a bit more torque (at 6v and 7.4v) than the Solar D772 for about $2.50 more. I'm guessing the titanium gears are bringing the price of the MG968 up over the MG959. So if I decide I need a 400+ oz-in servo and the MG968 is holding up, then they've got it covered.

Tower Pro MG959 388 oz-in/0.19 sec. @ 6v, 444 oz-in/0.17 sec. @ 7.4v.
MG959 Black (High torque for giant airplane) | Tower Pro

[wajahebat]

Im currently using one of these servos you guys talking about, TowerPro MG968.

The specs i found on the net for this servo max voltage is 6.6v @ 24kg torque, so i ran my BEC's at 6.7v. Quite frankly speaking, it is considerably fast and super strong. Ohh and im using 25T servo horn (axial metal).

Any advice if i push my voltage to 7.4v ??