Using a diamond core drill. any advice?

[saveasteading]

 

 

Tried another hire co today. £130 for the Hilti drill on stand for a week, plus a water tank, plus some expansion bolts to lift out the core (clever guy) adding up to £190.

It is a stock item but currently out on hire.

He also checked I had 110V, so altogether a good service.

 

The core drill however is a 350mm or so, long tube with tungsten carbide heads on it, about 10mm long.

£120 to buy or £25/mm used.

That's what I had expected, and not the expendable core bit offered by the others.

Hire and use 5mm and I'm handing back 5mm unused and paying £125.

Use 10mm and it is £250, and I should have bought it.

 

I absolutely don't know how much wear there will be doing 6 or 8 holes of 150mm with mesh, then into probably  brick hardcore.

Web pages all say 'it depends'. 

 

Any knowledge on the likely wear and whether to hire or buy?

I suppose I could buy it and offer to sell what's left back. That was not suggested though.

[markc]

Should be hardly any wear at all doing those holes, mesh doesn’t cause much heat or wear. Measure the bit before you take it and when you get back with a signature. They always put down 2 or 3mm of wear and impossible to argue when the invoice comes in.

[saveasteading]

7 hours ago, markc said:

Measure the bit before you take it

The one I saw was brand new, but may be gone by when I need it.

It had a sharpened bottom edge, which will cut better for a while but quickly wear off.

 

So you're saying pay by the mm.  The aggregate will almost certainly be beach gravel, so mostly flint. A hard but brittle material to cut through but the cores look pretty when wettened.

[markc]

6 hours ago, saveasteading said:

The one I saw was brand new, but may be gone by when I need it.

It had a sharpened bottom edge, which will cut better for a while but quickly wear off.

 

So you're saying pay by the mm.  The aggregate will almost certainly be beach gravel, so mostly flint. A hard but brittle material to cut through but the cores look pretty when wettened.

Morning, for your 6 or 8 holes I would be hiring the cutter. If it’s new then won’t be distorted or side worn so excess wear isn’t going to be an issue. concrete especially war time era around steel producing industries can contain a lot of slag which is very abrasive and a PITA to cut through. Keep the water flowing to flush the cut and let the cutter go at its own pace. And yes cores can look amazing, I used to have one we took from a bridge pier - it was more steel than concrete!