Best scales on a budget

Maxrate · #1 08-09-2021, 05:36 PM

Looking for input on a set of good scales to weigh a -7 that won’t break the bank. New aircraft scale prices are all over the map.
Thanks.

rjcthree · #2 08-09-2021, 05:45 PM

Used race car scales work well. Somebody will have them.

DRMA · #3 08-09-2021, 06:53 PM

Or check with your local EAA chapter. Many have scales for the use of their members, and membership dues are low.

I weighed mine with the EAA 302 chapter (Conroe, TX) scales. They do charge a small fee for use that covers the annual re-calibration of the scales.

Cheers,

GalinHdz · #4 08-09-2021, 07:29 PM

FWIW I use these 300Kg (660lb) Digital Postal Scales which work great. My airplane's BEW is less than 660lbs per tire so these are more than adequate.

Doug Rohrer · #5 08-09-2021, 08:59 PM

I bought the same scales as Galin and they worked fine for my -9A. Cheap enough on Amazon you can buy a set of three and loan them out to your RV buddies. Weight limit is too low for C172's.

swjohnsey · #6 08-10-2021, 04:22 AM

I have a pair of those as well plus a smaller electronic scale for the tail wheel.

erich weaver · #7 08-10-2021, 04:43 AM

Consider renting the scales from your local industrial supply store if you want to save the $ and not have equipment that rarely gets used lying around the hangar.

Erich

Ed_Wischmeyer · #8 08-10-2021, 05:01 AM

I wonder (but haven't done the math) how much accuracy is really required. If each of the scales is accurate to say within three pounds, and in the unlikely event that all the errors are in the same direction, is a nine pound error tolerable? (I don't know the specs for "certified" aircraft scales.) Also, at one point, factory built airplanes were not all weighed when they were built, but only every tenth airplane or so... Gross weight is important, but keeping the c.g. from going too far aft is really important...

Kyle Boatright · #9 08-10-2021, 05:10 AM

Quote:

Originally Posted by Ed_Wischmeyer

I wonder (but haven't done the math) how much accuracy is really required. If each of the scales is accurate to say within three pounds, and in the unlikely event that all the errors are in the same direction, is a nine pound error tolerable? (I don't know the specs for "certified" aircraft scales.) Also, at one point, factory built airplanes were not all weighed when they were built, but only every tenth airplane or so... Gross weight is important, but keeping the c.g. from going too far aft is really important...

A three pound error in the accuracy of the weight on the tailwheel would have a serious impact on the CG calculations. Depending on the direction of the error, it might reduce your (theoretical) baggage allowance by 15+ lbs or it might fool you into flying with the CG aft of limits.

riseric · #10 08-10-2021, 06:05 AM

The scales suggested by Galin are accurate to 0.2 pounds each at the 660lbs setting. That's 0.03%.

Anyone know how accurate are aircraft scales???