Correcting a cock-up !!
|Kevin Murrell||31/08/2021 11:23:42|
|50 forum posts|
Cock up on my part, but I could excuse myself as I was interrupted during the machining. Anyhow, I have drilled the centre hole in the beam off centre. It is drilled to 3/8" and should end up as 1/2". It's just about 1/8" off centre.
What are my options? I thought about using the mill and rotary table to open up the hole, but centred, to more than 1/2" and then fitting a brass bushing and then drilling that (on centre) to 1/2". Or perhaps mounting the beam in the lathe and using a boring bar to produce a centred hole.
Any advice gratefully accepted. Kevin
|pgk pgk||31/08/2021 12:40:58|
|2324 forum posts|
Easily done. I made a similar error yesterday with a brain fart and forgot to halve the thickness of the edge finder when measuring to place 2 holes...luckily realised after centre drilling and could redo and hide in the size of the final holes. A bushing sounds reasonable, and option of making it larger as a new feature?
|Howard Lewis||31/08/2021 12:46:22|
|5348 forum posts|
So, pgk pgk, you are a member of my "cock up club".
I get quite practised at bushing holes to put the original hole where it SHOULD be!
21467 forum posts
I think I would open it up to say 5/8" in the correct position or whatever it rakes to get a complete hole and then turn up a bush to fit the hole and bored to suit the pivot pin and Loctite in place. Plug could be steel
Or you could make the pivot pin from larger diameter material so that the central section is a nice firm fir in the hole in the beam
|pgk pgk||31/08/2021 14:14:06|
|2324 forum posts|
I’m also a member of the 'twice a many bits in the scrap bin as the finished item' club
|Phil H1||31/08/2021 14:55:40|
|403 forum posts|
'Twice club'??? I've built my Rob Roy at least 3 times and it is still nowhere near finished.
Loctite bush sounds good.
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