John Tomlinson is currently renewing the grate bottom for his 5in. Gauge Netta 0-8-0 locomotive, ready for the new season.

The project is based on the "Rosebud Grates" article, published in Model Engineer.

Starting point is a blank 8mm MS plate courtsey of Pete B. Plate is marked out at 7mm centres, spotted, centre-drilled, 3mm drilled, and countersunk.
225 holes in all.  Time consuming!
 
 
 

A test piece at totally different centres was tried and worked on New Years Day.
 This latest grate has considerably more holes but only 14% of grate area for air as opposed to 50% for regular bar grates. Hope it works!

Many thanks to John for sharing this with us.