Hi Tony,

As they are through holes I would be inclined to drill through to clean the thread out – and, as they are drunken, preferably using a slot drill to true the bore if the depth is not longer than the cutter – then counter bore the lower face about a millimeter more on diameter for a short depth. Turn up 'top hat' pre tapped bushes a reasonable fit and assemble with Loctite finishing off as you say. If you make the bushes from CI and don't deburr the holes before fitting the bushings after cleaning up the faces the joins will be near invisible. The top hats can be though drilled or blind

This method works well and is very strong with a minimum of 'attention to fits' required.

Hope this helps

Regards- Ramon

If the design allows it you could just true and enlarge existing holes , tap M6 and use M6 bolts .

As the flange on the top-hat is on the underside it stops the bush being pulled out by the M5 fixing.

J

Neil, what material are you talking about, with reference to filling with arc weld.I have been known to fill a hole in steel plate with MIG weld and it was not a very small hole, neither was it that big. Ground off afterwards and you could not tell.

As Michael says, because the thread pitch of M5 and 3/16 BSF are in essence the same, the M5 being 0.24mm larger in diameter, then you should be able to true it up to M5 if you guide the drill & tap perpendicular to the surface and get a good thread.

Personally I would tap M5 or M6 and use M5 or M6 bolts.

Another alternative is, if the design will accommodate a stud and nut arrangement rather than a bolt and threaded hole, then you can tap the hole M6 and make a stud M6 one side and M5 the other.

Nigel

Tony,

As an aside … there is a useful article about the Brooks-Stent, on the GadgetBuilder website.

However; noting that yours is Cast Iron … this article may be of more interest.

MichaelG.

.

Edited By Michael Gilligan on 25/10/2012 09:08:37

Edited By Michael Gilligan on 25/10/2012 09:14:16

Hi Kwil,

I''m not 100% sure what it is – Its a slice off some random 5/8" plate, but it machines like an unleaded mild steel.

The drill came out the far side and marked the jaw of my cheapo drill vice. That means its a trough that I can't tap or plug. I need the new hole to overlap, so filler is put of the question.

It's a tangential tool holder to fit my QCTP (a brilliant idea I ought to have patented!)and the hole for the clamp to hold the tool in place was the last operation :-0

If it's dry tomorrow I'll have a go at welding. I'm banned from welding and brazing under cover now after buring a hole in the side of a mop bucket and putting my wife's bike at risk. A bit harsh, I feel, it's not like I welded the dog to something.

Neil

Edited By Stub Mandrel on 26/10/2012 20:59:28