Friday, March 31, 2006

PROPper job

Propshaft Collar
Originally uploaded by Phil_Parker.
Back to the boat at last.

The next job (I think) is to get the working bits fitted. Looking at the motor I need to attach it to the propshaft using the coupling I bought at the show.

The coupling is a very nice glass reinforced nylon and brass universal joint. It wasn’t expensive and seems pretty well engineered. Each end has a removable brass bit that attaches the motor or the propshaft. The motor end is fine, a collar with an Allen screw to tighten against the shaft.

The other end was wrong though. I managed to buy a part that was threaded. Of course the shaft wasn’t. The idea of screwing the shaft into the collar doesn’t sound too smart anyway – surely it should just unscrew itself when you run in one direction ?

No – it was time for action. I prevaricated for a few days and then did the job in about 20 minutes. Typical. When I think something will be a quick job it takes ages as everything goes wrong. Get a difficult job and it falls together. I suppose I just did the all the planning in advance – yes that must be it.

First the shaft was measured – 4mm. The collar was drilled out so the shaft was an easy fit. Then I drilled across the collar with a 2mm bit and tapped the hole to 8BA. A shortened bolt locks the shaft by locating into a flat filed in it.

This all sounds dangerously like a proper engineering job ! Drilling and tapping things ?

Normal service will be resumed with some bodging soon.

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