The place for technical discussions about GA and flying.
Forum rules: Technical discussions about GA only, please.
We have a set of 2000Kg platform scales (4x 500Kg pads) we use for W&B. ±0.5Kg. Also ramps and hydraulic levelling platform.

Best if you can fly to us in mid Hampshirebut if the aircraft is not flying it might be posible to make a plan. I do sometimes travel to Turweston/Silverstone.

They cost ££ to maintain so we have to make a charge.

I recently weighed my aircraft with standard bathroom scales, using a strong plank of wood supported at one end on a block, other end on the scales and each wheel in turn at the centre point.
Multiply by two.
Worked ok but then I was advised that the weigh in has to be witnessed by my inspector, who has a set of certified scales for the purpose!
has to be witnessed by my inspector

Not true.
The weighing may be performed by the owner/builder with calibrated scales in a way that is acceptable to the inspector and the LAA. This may be by the trust the inspector has in the owner/builder and/or the quality of the person or company employed by the builder owner to perform this task and the production of the relevant paperwork on the approved forms.

My own scales are calibrated by a company with a traceable national standard and also I have a calibrated set of weights (up to 350kg) that I am able to use in-between 2 yearly calibrations to confirm that the scales are still within tolerance. Once at an airfield prior to weighing a gross error check is also performed on each scale to ensure nothing has gone awry during travel to site.

For an LAA aircraft the results are written up onto the approved LAA forms and various loading examples are calculated using loadings called up in the BCAR rules.

There is nothing inherently wrong with using a set of bathroom scales provided there is a means of calibrating them and providing you level the aircraft correctly for each reading, thats not just lifting up each wheel and plopping the wheel on the scales in turn !
I didn’t just “plonk each wheel in turn”.
I levelled it on a trestle, blocked each main wheel level with the scales.
What he meant was that the scales should be calibrated, results recorded correctly CofG calculated correctly etc.
I have an Excell spreadsheet which he was quite happy with. My results were within a pound of his calibrated set.