Being a (-nother) Swedish cheapskate, I just couldn't let IKEA go totally unnoticed... Thus this ...ahem... "structure" is entirely held together with M8 Allen Bolts, and could (but won't) be stowed in your trunk in a nice, flat cardboard box (Allen key included) of 60 x 7,5 x 7,5 cm... Profile is 70 x 15 mm, with a nice T-slot on each broadside & 2 mm thickness. "The Higher Power" also had it app 30 mm width at the bottom and (surprise!) a 1/2" top slot, where yours truly will slip-fit a few Meccano strips under the carriage (below right) to keep it "true to thyself". And: I finally realized where the gazillion of these steel 1" squares w M4 holes lying all over the place a few weeks ago came from - "Slip-nuts" in the slot, of course. Loosen and they slide, tighten up and they'll lock. Enough sideplay to allow for the 1:12 angle of the "Business End" of this Freelance Version", Add a rubber washer on each "nut" and this frame/ carriage will REMAIN in place till kingdom come. Good thing I kept a coupla dozens of these square nuts - they came in handy faster than even I assumed (my colleagues are "sceptics")! BTW: Hex Nuts are less square - they're hip.