long steel seat post

[sjpt]

Does anyone know where I can source to have a 450mm 28.6mm steel seat post?
Baz???

For the front of an Ecosmo tandem; the standard one isn't long enough for me (even though I'm only 31" inside leg)
I've got an aluminium one but I'm not sure I trust it, especially with the stoker's handlebar adding stress to it.

Moving from full size (Viking) tandem as the crossbar is easier, and we may even take advantage of the folding capability.
We don't do many rides much over 10 miles now so the small tandem should be adequate.

 

[guerney]

Would cutting this down to 450mm...

https://www.ebay.co.uk/itm/202664070766

...and using two shims up to 28.6mm work?

https://www.ebay.co.uk/itm/334581114691

...or would the seatpost slide down when it rains?

 

[sjpt]

Thank you for the suggestion. I wouldn't even cut it down, just leave more insert room.
Double shim seems a shame, and I'm not sure how much weaker a 22.2 diameter tube would be than a 28.6? (obviously depends on the particular tube)

I think I've located a second hand one I'll probably go for even though it has surface rust.

Steel Chrome Bicycle Seatpost Straight 480 mm x 28.6 mm

TECH APPRAISAL: Item in good used condition, some evidence of rust Colour: silver Length: 480mm Diameter: 28.6mm Material: steel Weight: 510g

piorabikes.co.uk

but if that doesn't work out I might go for your suggestion.
Meanwhile I'll keep a careful eye open for any faults developing in the alloy one.