I am new to the world of small foamy planes and their setup. One of the things confusing me is servo's!

So I'm putting together a Squall that calls for 9-10gr micro servos. I had some Voltec micro servos left over from a Precision Aerobatics plane and thought all was well. Then one of the servos tested bad. So I order a Hitec HS-85 that was suppose to be a micro servo; except it's twicw the size of the Voltec servos

Here is my BIGgest[:-] question _ when a plane calls for a 9-10gr servo, what is that referring too? I suspect it refers to servo weight, not torque; am I correct?

2nd question: it appears to me that there are several sizes of what companies call micro servos. How do you determine what physical size of servo is required?
thanks.

Hi,

Yes, you are correct about the 9-10gram (0.3oz) servo being its weight as opposed to its torque. This size servo is generally referred to as a sub-micro servo. The class definitions have changed over the years but seem to be more stable now.

I would put the HS-85 into the micro class because it weighs 0.67oz or 19g. Another example of a micro servo is the Futaba S3115 at 0.6oz.

A mini servo would be something like the Hobbico CS-35 at 0.96oz and most standard size servos weigh around 1.6oz. Although the weight and size can vary slightly, the sizes follow categories like this:
[ul][*] Standard servo = 1.6oz[*] Mini servo = 0.9oz[*] Micro servo = 0.6oz[*] Sub-micro servo = 0.3oz
[/ul]

Hope this helped a bit...

For your squall, 9gs such as the Hitec HS 55, are fine. You may also want to look at the Hextronic 900's from hobbycity.com . They are inexpensive, about 3 bucks a servo but from most reports, they are stronger and perform just as well if not better than the Hs 55.

I would agree with Sloppy Joe, the HexTronic would be a good choice. I have about 18 of them in various foamies, and they have been working very well. When you go to the hobby city website, be sure and select the ones that are stocked in the USA warehouse. They are a dollar or two more $, but have even better internals. I will update this reply later with a link.

Here ya go!

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=8306&Product_Name=HXT900 _9g_/_1.6kg_/_.12sec_Servo_(USA_Warehouse)

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Vriendelijke groeten Ron
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