Anchor modification, specifically 'moving' the centre of a 10mm hole by 2mm

[Neeves]

I am modifying a developmental anchor and one of the 10mm bolt holes holding the anchor together is located with its centre 2mm out of line. I want to use the existing pieces rather than start again. I want to move the bolt hole 2mm from the existing centre. The new bolt hole, one of 3, will then be oval (the other holes are in the correct location). The hole I need to 'move' secures a sandwich of 5mm aluminium, 5mm stainless plate and a stainless casting. The stainless casting will hold studs, its drilled and tapped, and I want to move the holes in the aluminium and stainless plates to match the hole in the the casting.

filing by hand seems a bit crude.

I am sure there is a device I can hold in a hefty bench drill chuck that will allow me to ream (is that the word?) sideways. A sort of rotating file or drill bit that will enlarge the existing bolt hole, sideways, with a degree of accuracy. The hole, ideally, will be 'sort' of rugby ball shaped. semicircular ends joined by flats, one end is the existing hole - I just need to machine the other side to 'make' the oval

I need to know what is such a device is called, who might make the device. I appreciate that I will be sourcing the device in Australia and most recommendation will be British, or European. I'm used to that and should be able to cope.

In the fullness of time and with success all will be revealed. If my ideas are wrong the concept will be quietly forgotten and I'll find another solution to the problem (like making new plates from stainless and aluminium.

With thanks

Jonathan

 

[pandos]

I have used these things to do similar, although, bought from Amazon. I have a straight highspeed tool from aldi which holds them. I suspect a drill would work as well.

 

[William_H]

I am not clear if it is ali or ss you need to cut. If ali you might succeed with a router bit made for wood. For SS you might be able to find a stone on a shaft made for sharpening chin saws. Or just get the round file out. Is seem to have history of similar miscalculations and need to move holes.good luck ol'willl

 

[Neeves]

I have used these things to do similar, although, bought from Amazon. I have a straight highspeed tool from aldi which holds them. I suspect a drill would work as well.

I have the same set as you, in fact ended up with 2 sets. I found them a bit crude and hoped there was a more professional tool.

I am not clear if it is ali or ss you need to cut. If ali you might succeed with a router bit made for wood. For SS you might be able to find a stone on a shaft made for sharpening chin saws. Or just get the round file out. Is seem to have history of similar miscalculations and need to move holes.good luck ol'willl

I need to machine the holes in both the stainless steel and the aluminium. The aluminium is (probably) not an issue the stainless is hardened. I have a tapped, 3 taps, cast stainless component which is bolted to an aluminium fluke plate and a replaceable (consumable) stainless toe plate. The 3 holes in the stainless cast component don't fit one of the holes of the aluminium and hardened stainless plate. The whole device is to be held together with high tensile bolts, or studs with nuts.

I've not machined hardened stainless but have machines Q&T steels 800MPa (and destroyed the gear box in my Bosch angle grinder). I'm not familiar with hardened stainless but know it might take longer than I think. I'm honing my patience.


This is a first full sized test piece. Longer term I think I will replace the aluminium plate with a steel alloy plate of 1450 MPa - but want to test what I've got first as sourcing small pieces of Q&T steel or even aluminium sheet and plate needs more than enough charm. I need to use all three bolts if I want to test the anchor under full load


Does the world need another anchor?...... of course not. The intellectual challenge is part of my therapy keeping my brain active.

Why my reticence - last time I made something open source, not on YBW, someone copied my idea (I have no issues with people who copy) actually claiming the idea as theirs. My tolerance has limits - but there is nothing I can do as I do, eventually, feel the need to share.

Jonathan

 

[jakew009]

The easiest way of doing it would be on a milling machine.

Clamp it in the vice, put the milling cutter in the existing hole and then move sideways 2mm.

Maybe see if the can find a helpful engineering shop who would do it for you?



Failing that some sort of grinding tool on a dremel or die grinder would eventually do it. I don’t think you will have much luck with a drill bit in hardened stainless.

 

[AMOREST]

Drill the right diameter hole in another piece of steel and clamp or tack to the piece - then drill through using the hole as a guide.

 

[Minerva]

Could you not weld the holes closed the re- drill in the correct location?