Hacker/Ditex servos
#3
Thread Starter
Hope this helps, Jim O
#4
My Feedback: (4)
Most of the world uses Newtons instead of pounds for force and meters instead of feet for length. So in Germany, torque would be specified in Newton-meters or in this case Newton-centimeters. If you have an iPhone you must have an app called iConvert. You can then convert N-m to in-oz. You would need to divide N-cm by 100 to convert N-m. So 162 N-cm (1.62 N-m) equals 229 in-oz.
Hope this helps, Jim O
Hope this helps, Jim O
#5
Thread Starter
Jim O
#6
My Feedback: (4)
In the US pounds is used for force and also for mass by most people (units for mass are really slugs) and sometimes it is not clear so you might see them specified lb f or lb m. In the International System, kg is used for mass and Newtons for force to distinguish between. When we are talking about torque we know it's force and we assume we can convert kg to pounds by dividing by 2.2. So you are right it is a lot easier for most Americans to think in terms of kilograms than Newtons.
Jim O
Jim O
As I said, I haven't seen n-cm used before for servo force before now.
#7
Metric and imperial servos measurements are show by the following manufacturers but there may be others: Airtronics ( 31 servo models) Futaba , Hitec, Spektrum and MKS . Not a big deal as easy to convert but both would be nice.
Off shore kit or ARF manufacturers usually ( not always) list minimum servo torque ratings in their manual unless specifically built for an American distributor . Have to check the manuals.
Off shore kit or ARF manufacturers usually ( not always) list minimum servo torque ratings in their manual unless specifically built for an American distributor . Have to check the manuals.
#9
Thread Starter
Yes I'm well aware of who uses which system for measuring force. Ft-lbs and n-m are not relevant to this thread as the force of the servos we use are no where near that high. Hence the use of oz-in and kg-cm. These are the 2 most common ones used.
As I said, I haven't seen n-cm used before for servo force before now.
As I said, I haven't seen n-cm used before for servo force before now.
Anyway it is good to be able to think in metric units nowadays, although I still have trouble with grams and need to convert it to ounces so I guess I shouldn't talk.
I'm anxious to get some reports on the Hacker-Ditex servos.
Jim O
#10
' Anyway it is good to be able to think in metric units nowadays, although I still have trouble with grams and need to convert it to ounces so I guess I shouldn't talk. '
Hi Jim,
This might help with thinking in grams ; Think about WATER
Most know this but don't realise it.
1 Millilitre = 1cm\3 - weighs 1 gram
1,000cm\3 = 1 Litre - weighs 1Kg
Brian
Hi Jim,
This might help with thinking in grams ; Think about WATER
Most know this but don't realise it.
1 Millilitre = 1cm\3 - weighs 1 gram
1,000cm\3 = 1 Litre - weighs 1Kg
Brian
Last edited by serious power; 02-12-2017 at 02:12 AM.
#11
Yes Brian at 4 Deg Celsius. But at 20 Deg its dropped to 998 cm3/litre and at 0 Deg in liquid state its dropped again to 999 cm3/litre and even lower to 915 cm3/litre as it solidifies.
You can see I had nothing better to do on this cold windy winter's afternoon than argue with you Brian!
Malcolm
You can see I had nothing better to do on this cold windy winter's afternoon than argue with you Brian!
Malcolm
#12
Hi Malcolm,
It's always 4 Deg in Ireland
Funny stuff water ; Gets less dense as temp increases above 4C and also less dense at temp decreases below 4C.
Brian
PS ; Did you mean Gram/Litre ? You forgot to specify an altitude
It's always 4 Deg in Ireland
Funny stuff water ; Gets less dense as temp increases above 4C and also less dense at temp decreases below 4C.
Brian
PS ; Did you mean Gram/Litre ? You forgot to specify an altitude
#14
Hi Malcolm,
There was I thinking that there were 1,000 cm\3 in a litre - regardless of the density of the substance occupying the volume and even in a litre of vacuum.
I think Grams/Litre.
Brian
PS ; We're not helping Jim much
There was I thinking that there were 1,000 cm\3 in a litre - regardless of the density of the substance occupying the volume and even in a litre of vacuum.
I think Grams/Litre.
Brian
PS ; We're not helping Jim much
#15
Thread Starter
I must admit the SI system is pretty neat and it is strange the US is one of the few countries that doesn't use it. But how do you guys know what a Newton-Meter is? Is it a Joule or is it .7375 lbf-ft? In the US we use ft.-lbf for energy and lbf-ft. for torque. Seems like a Joule ought to be a Meter-Newton?
Things are pretty slow here also. We had to cancel our "Pattern Camp" this weekend due to weather. One of the problems with electric power is there isn't much maintenance required and the aircraft don't wear out. What do we do when the weather is bad? Not much happening on the web either. I'm happy to see you guys are alive and well and have nothing better to do either.
I guess I should spend my afternoon remembering 28.349 and .03527. But I've always got iConvert on my iPhone if I can't remember.
Jim O
#16
#18
Brian,
Just seen this, of course, brain fade! I did mean g/Litre.
Must be the cold!
Jim, I'm a hydraulic engineer working in the offshore industry with many of your colleagues. Even more confusing is the fact that your flowrate of gallons per minute is different to our old imperial unit. Yours contains 231 in3 and ours was 277.4 in3. Its amazing the number of times people this side of the pond get caught out by that one when converting to Litres.
Malcolm
Just seen this, of course, brain fade! I did mean g/Litre.
Must be the cold!
Jim, I'm a hydraulic engineer working in the offshore industry with many of your colleagues. Even more confusing is the fact that your flowrate of gallons per minute is different to our old imperial unit. Yours contains 231 in3 and ours was 277.4 in3. Its amazing the number of times people this side of the pond get caught out by that one when converting to Litres.
Malcolm
#19
Thread Starter
Brian,
Just seen this, of course, brain fade! I did mean g/Litre.
Must be the cold!
Jim, I'm a hydraulic engineer working in the offshore industry with many of your colleagues. Even more confusing is the fact that your flowrate of gallons per minute is different to our old imperial unit. Yours contains 231 in3 and ours was 277.4 in3. Its amazing the number of times people this side of the pond get caught out by that one when converting to Litres.
Malcolm
Just seen this, of course, brain fade! I did mean g/Litre.
Must be the cold!
Jim, I'm a hydraulic engineer working in the offshore industry with many of your colleagues. Even more confusing is the fact that your flowrate of gallons per minute is different to our old imperial unit. Yours contains 231 in3 and ours was 277.4 in3. Its amazing the number of times people this side of the pond get caught out by that one when converting to Litres.
Malcolm
Yeah, you guys pulled a fast one. You gave us the small gallon and then after the divorce you changed the rules and came up with the big Imperial Gallon. Luckily my iPhone knows that too.
It looks like we need you and your colleagues in California. For years we've been in drought conditions and now we have too much water and it is causing havoc.
Jim