I have one of those large metal self-assembly shelf units made from five shelves welded from thick wire (thin rods) and eight hollow metal half-poles that are joined by four cylindrical springy inserts.
The inserts are slotted cylinders of springy sheet metal, about 10 cm long and 2 cm in diameter. Two of them are free and two of them somehow got shoved down into the poles so that there's nothing sticking out to grab a hold of.
The cross-section of the inserts is not circular, it is wider in the direction containing the slots and a few millimeters narrower on the sides.
I only have basic "apartment tools" but there are plenty of DIY and machine shop supply stores around if there's something specific that I can buy to try to pull these out with.
Question: How to extract the cylindrical metal inserts that hold the two halves of the poles together for steel shelves?
I'm thinking that WD-40 or similar is one of the ingredients, but I don't know if I should try to find strangely shaped, strong, thin needle-nose pliers, or some kind of hook device...
note: That handy-looking hole at one end is near the top in one pole-half, but at the far end of the insert in the other.
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