Hi Sumpter250 and Nachoman
Didnt take that long, a few hours, each of the four rail grooves only took a minute or so of actual cutting, the longest part is setting up the angles.
By the way I didnt mill it, I used my trusty shaper, ex Narwee Boys High metalwork room, had one exactly the same at Punchbowl Boys High, spent many a period happily turning a big bit of metal into a smaller bit, its probably late 50's early 60's vintage, but good as new, unlike me.
You may be able to make it out of hardboard, but soldering iron may char the wood and any flux could cause it to swell. But have a go anyway, its good fun.