Servo quality

[wibblywobbly]

I don't know about anyone else but I seem to have suffered from numerous servo failures over the years, even using metal geared ones. Recoil works fine for a while, then I switch a tank on one day...and the servo is simply locked up solid. Knocking a barrel on a solid object may play a part.

I see on Hobby King that in the description for the HXT900 that they state that there are two versions. The export ones are higher quality and that the ones sold on Ebay etc are the imported home market ones. I have just ordered four of these Hobby King ones, but I am wondering whether anyone knows whether their claim is valid?

I also wonder whether the micro servo's are man enough for metal barrels etc, they should be with a 9kg pull, but the failure rate seems a bit high. It would make more sense to buy more expensive larger servo's that would last forever than keep buying these smaller ones, even though thay are harder to shoehorn in.

Using a geared recoil, rather than a servo and arm method will probably place less stress on the servo, so over the coming months I will try and convert my tanks and see if that works more reliably.

[Tankbear]

I've had more failures with larger servos than micro servos. Think the servo electronics are prone to easy damage of voltage so if your electronics spike the voltage when turned on could kill them.

[ausf]

I've been using Hextronix servos for years and never had a failure yet. For servo recoil, rudders on subs and MTBs, 500s or 900s. They are excellent.

As far as two different ones, I think that's rubbish. What would a company gain buying making two versions, one prone to failure? I know I'd never buy a product from a US company if the export was better. I could see them claiming there are fakes on eBay, but bad Hextronics would ruin the brand.

The ones on eBay are usually more expensive anyway since you are paying a middleman.

I buy direct from HK for anything anyway, even if it's in the US warehouses. The Chinese government subsidizes their postage, so I can grab a pile of servos from HK for $3-4 shipping while using their local warehouse it would be $8 ad only be a week faster.

[wibblywobbly]

Well so much for export quality, I bought four, one stripped the gears when it wasn't hooked up to anything at all, and one stripped the gears after being used in a freely moving recoil about 5 times? One is working ok, and I am now down to the last one...

[ausf]

I don't know what to tell you, nowhere near my experience. The upside is HK stands behind their stuff. They usually don't want things like Rx or servos returned, they just credit your account of refund. I had one Orange Rx DOA that I didn't even try for a few months and they credited me.

Like I said, I use HXTs for everything, the biggest load being rudders for RC boats which are under a heck of a lot more strain than any recoil unit. Especially the subs, where the pushrods have to pass through a series of O-rings and cup seals.

I just ordered another 14 of them two days ago.

[wibblywobbly]

Are you using the cheapie blue plastic ones? The HXT900, or something that is more robust?

[AlwynTurner]

I use these micro servos for the Nashorn and they seem to work fine but obviously they haven't had a long workout, but being for aero modeller use I think they should be fairly robust.
http://www.ebay.co.uk/itm/162304325066? ... EBIDX%3AIT

Alwyn

[ausf]

Are you using the cheapie blue plastic ones? The HXT900, or something that is more robust?

Yeah, the 500 and 900s. The 14 500s I just ordered were like $2.50 each.

I use them in so many applications, driven by RC or Arduino and usually a oneway trip, so I'm pretty confident in them. I put three of them in an old Aurora Frankenstein model to animate the arms and head that will never see the light of day again.

It has to be 4 or 5 years now when I switched from Futaba to them and haven't had a failure. The only mishap so far was when one application required taking the bottom of the case off to fit and I broke the solder of a motor wire during installation.

I've seen guys using them is some serious sub models without issue. The loss of a servo in a body of water (or under) would be pretty severe compared to a tank.

Maybe there's a greater load on your applications than you think and you need to go to metal geared servos.

Here's two applications, you can imagine the stresses on these:

The MTB is one servo running both brass rudders, in the sub WTC, one 500 is triggering both a switch and activating a valve with pushes a 3mm brass road through a series of seals and rotates a drum. THere's significant force on it in both directions.

phpBB [video]

phpBB [video]

[keno]

Good morning all, ausf, is that the workings of a submarine? Where could one purchase a decent sub for the pool that would look authentic to a real one? I didn't know there were some but thought it would be Kool...!

[ausf]

Good morning all, ausf, is that the workings of a submarine? Where could one purchase a decent sub for the pool that would look authentic to a real one? I didn't know there were some but thought it would be Kool...!

Yep, that's for 1/72 Revell Type VII.

In terms of buying a kit, I'm not sure, I know Engel makes them, you can start there first.