Anyone pull on a crane scale

[TJay 1041]

Anybody hook a crane scale up behind your plane and see how much pull it has with your engine prop combo, I'm thinking about buying one off ebay there only 30 to 50 bucks for the smaller ones, If I do would you guys want to pass it around the forum and record your numbers, Just a fun thought,

[1avidflyer 1983]

A friend of mine has a 350 lb meat scale that we've used.  With a 582 I was able to pull about 310 lbs with a 3 blade IVO.  A 3 blade powerfin pulled 305.  With the 447 in my Himax, I was able to pull 245.  I'm trying to remember the # with the Jabiru engine, and I think it was 280, but can't say for sure.  Where we were set up with the Jabiru was a slight up hill which would have given a lower reading.  JImChuk

[akflyer 1427]

I am down for pulling on a scale!

 

[Av8r3400 1179]

Count me in.

I'll show you what it's all about...

[lostman 198]

Great idea! My dad and I use a similar small scale when designing and changing props on our aircraft. I'd love to pull mine (Teenie Two) but I've never had it where the scale is since I live 2,400 miles away from him. Guess I should actually just buy another scale really. 

I'd love to see actual real life numbers from you guys to see what you are getting. So many pilots claim that a prop made a difference but it's all feel in the seat, not numbers.

[TJay 1041]

Well I have read a ton of reviews on these and it looks like the biggest complaint is the digital ones don't register when the load is bouncing around, Probably not gonna work for these tests,

[akflyer 1427]

It does have to be digital mr!  I would be up for going in on one with you just so we can get real numbers.  I think we have members on the forum using about every combo of prop and gear ratio out there so it would really be nice to see what gear ratio and what prop is pulling the hardest... I will come up with a matrix to fill out for temp, altitude, engine, gear ratio, prop, pitch etc that can make the rounds with the scale, or everyone can just report the numbers back here and I will fill it in to keep track. 

 

 

[1avidflyer 1983]

Some say that static thrust isn't all there is to performance, obviously if the prop is cavitating, it won't make the thrust of one that's "hooked up" with the air.  I do know I didn't get as high a reading with the Jabiru prop as I got with a 582 and 3 blade IVO, but take off was about the same, and cruise and top speed with the jab was better.  Still interesting to have the numbers.  JImChuk

[TJay 1041]

It does have to be digital mr!  I would be up for going in on one with you just so we can get real numbers.  I think we have members on the forum using about every combo of prop and gear ratio out there so it would really be nice to see what gear ratio and what prop is pulling the hardest... I will come up with a matrix to fill out for temp, altitude, engine, gear ratio, prop, pitch etc that can make the rounds with the scale, or everyone can just report the numbers back here and I will fill it in to keep track. 

 

 

Yeah I thought that too the issue with the older manual ones I found were so big and bulky they would cost everybody a fortune to ship. Ill keep looking around.

[1avidflyer 1983]

Here is one of many like it on ebay.  Don't know how it would be if the plane was kind of jerking and such.  JImChuk

http://www.ebay.com/itm/Portable-500-KG-1100LBS-Digital-Crane-Scale-Heavy-Duty-Industrial-Hanging-Scale-/252537710756?hash=item3acc6ba8a4:g:z54AAOSwGtRX17Wh