THE ARRAN BOATS BLOG
Making and drilling keel bands for an Arran 16
I have a secondhand Arran 16 in which requires new keel bands.
It takes two 4m lengths of 40mm x 3mm 316 stainless steel bar to do the job.
If you cut the length of one of the bilge keels from one of the 4m lengths and the other bilge keel from the other 4m length its easier to handle.
Bend the bilge keels to shape in a vice and mark holes approx every 9″.
Try to avoid placing the new holes near the old ones.
I drill the holes in the stainless using a HSS 5mm drill bit and CT90 cutting and threading oil.Keep the drill on a slow speed and avoid overheating the drill.
The next step is to counter sink the hole using a 10mm drill and again I use the cutting oil.Finally i use an expensive countersink bit to finish of the hole.Each hole is tested using the screws to see if they sit in the holes correctly or if they are proud.
Once all the holes are drilled I clean the bands using acetone to get the oil off them.The oil would prevent the mastic from getting a good grip.