A 7.5mm slot with a 5mm internal radius at one end…

[FMESParticipant @fmes]

Amazing how a discription can be mis read, in this case on my part?

The way I saw it was a 5mm radius is 10mm diameter, with a 7.5 mm slot running into it over 20mm

So, set up in the mill and find centres, fit 10mm end mill, move to desired position and plunge in for the thickness required, then, run back out keeping centres aligned, change cutter for 7.5mm (probably accurate enough in this instance) and then run back in to the 10mm dia hole

Simples

However, as some have said, a picture would have helped greatly.

Edited By *.* on 11/02/2018 13:10:23

[Robin GrahamParticipant @robingraham42208]

Thanks for further replies/suggestions. The parts I'm replacing are indeed moulded plastic (a failure waiting to happen), so I thought an alloy replacement would be an upgrade. I did think about using steel but was worried about corrosion by rusting and galvanic effects as the frame of the buggy is aluminium alloy tube and the joint is going to get wet.

I made a broaching thingy out of silver steel this PM and shall have a go with it tomorrow,

Hopper – I'm afraid I haven't told the full story. The axle of the wheel which fits into the slot is actually M10 threaded bar, and whilst the A/F dimension is a pretty good 7.5mm, using my super-precision Mitutoyo mic I find to my horror that the bar is actually 9.872 mm over crests, so I may have to rethink everything . Seriously though, I get your point. But who never made a mistake never made anything as they say.

Robin

[HopperParticipant @hopper]

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