Thread: Drilling round stock - solved

Colleagues,
As you read this you will probably say "You stupid old fool, I could have told you that ages ago" but the older I get the more I seem to forget, I blame the Aluminum pans in the 70's.

For some time I have been mulling over a problem with the little wheels on a plastic trivet the supports the glass platter in a microwave. At home the children often put containers in the microwave to reheat their food "Great you say, they are finally 'cooking for themselves'", but they often put the container in so that the platter is stopped from turning and this wears little flats on the wheels and so the trivet never goes around. I can, and have in the past, replaced both motors and trivets but I thought there must be a better way.

So I bought some high density 17mm round nylon stock and thought that it would be a doddle to drill it out with a 1/4 inch hole but even with punching the drill bit tended to wander giving an eccentrically drilled hold and they wouldn't turn around. (Before you shout at me I don't own a lathe). The rod is too big to go in the drill press chuck otherwise I would have done the clamp the bit and have the round stock in the drill press so having, unsuccessfully tried several methods it has nagged at me for the last month or so.

Yesterday I had a flash of inspiration whilst drilling a hole with a spade bit. I got a piece of 5mm aluminium and screwed this to a small piece of hardwood, next I drilled a 3mm hole through both. Now I took off the Al and used a 17mm spade bit to drill all the way through the hardwood making sure that it was centred on the pilot hole. Now refit the Al and drill the 1/4 inch hole. Insert the 17mm rod through the large hole and up to the Al, clamp on the drill press table with the rod going through the centre hole and voila centred 1/4 holes. I used a Japanese flush cutting saw to get them 4mm thick and have cut a year's worth of supply. Now all I must remember is where I put them!

Regards

Mike