Diamond cutting discs for angle grinder?

[RonA]

Just been watching a youtube video from the USA about cast iron repair. Apart from the repair the guy was extolling the virtue of diamond cut off discs for cutting metals.
I use the 1mm abrasive cut off discs but whilst they perform brilliantly, the fact the diameter decreases as they wear is a bit of downer. The idea of a diamond blade which doesnt reduce in diameter seems attractive & according to the guy in USA they last & last.
Anybody using diamond discs & any recommendation on quality makes?
RonA

 

[julianf]

Years ago I picked up some scaffold bar from a chap to use as rollers. He insisted on using a diamond blade in his grinder to cut it when I collected...

Took ages to cut. I didn't care as it was him doing the cutting and his tool, but it was clearly not working well.

Maybe just get some cheap Aldi discs and try?

One thing I do know is I have an expensive diamond wheel on my precision grinder (precision as in I use a measuring microscope to check cutter dimensions when they've come off the grinder)

...I'm told that grinding hss on the wheel will wreck it (somthing about filling the voids) and, at close on £150 for the wheel, I'm not going to test!

 

[Seadog]

I don't think it's recommended using diamond discs to cut metal. As Julian says, they clog up. they're meant for stone and masonry etc.

 

[Al Strachan]

old slitting discs make excellent 1mm spacers for fabricating when you need to leave tolerances for paint/future rust etc, and theres been many occasions where i could only access the cut with a really worn disc, so there are positives to take from their short lifespan, plus the fact a pack of 10 is less than a tenner

 

[Kayos]

I had the same grinding disc in my Dewalt grinder for years, was a diamond disc used for chopping metal, stone, roof tiles etc

Not ideal but easier than getting up 3 stories of scaffolding and needing a different disc

 

[RonA]

I don't think it's recommended using diamond discs to cut metal. As Julian says, they clog up. they're meant for stone and masonry etc.

The ones the guy in the USA was using were designed specifically for cutting metals, maybe something new that has travelled across the pond yet.
RonA

 

[Pete.]

Cutting steel with diamond causes the diamond to break down very quickly as the edges dissolve. There are a myriad of different grades out there, some designed for heavy steel but most of what you will find will be specifically for cutting concrete. The binding matrix will be too hard for steel cutting which means that the erosion rate is too low ( the blade relies on the abrasive fines in the concrete to grind the segments away and expose fresh edges). This causes the dissolved edges of the diamond to stop cutting and the blade overheats, causing more damage to the diamonds. Eventually the whole blade is unusable even if you sharpen it manually.
Lots of factors involved, but that's the basics.

 

[Al Strachan]

i'm a project manager in the oil and gas industry, and my current project is to deploy a DWS subsea to cut a 30" diameter riser as part of a platform decommissioning program. These things are very sensitive to wire speed and cutting force, but obviously benefit from being fully submerged in water to keep them cool.

A bit impractical to have in the workshop though !

 

[Pete.]

Wire is probably the most sensitive to coolant diamond cutting you can get. Big money if you mess it up.
I should think that your biggest concern cutting those legs is closing of the gap at the end of the cut. Once you pinch that wire it can cause all sorts of trouble.

 

[desmo11225]

That's a brilliant video Al Strachan , I have not used a diamond disc for cutting ,but have a little circular saw sharpener will sharpen saw up to 30mmm dia I think and that has a diamond disc from China and it sharpens TCT blades easily , just a little touch on each tip I also have one in my grinder which is mounted on a Wolfcraft stand ,very good. desmo11225

 

[brightspark]

most diamond blades are not designed for cutting steel even rebar in concrete. it does them no favours and they don't cut well or last long they are available but at a high premium http://www.diamondkingtools.com/diamond-blades/metal-cutting-diamond-blades.html

 

[RonA]

Had another lok at cast iron welding video & the diamond cut off discs the guy is banging on about are these https://www.lenoxtools.com/pages/lenox-metalmax.aspx
Claim theyre good for a 1000+ cut off operations & cheaper than abrasive cut off discs per cut.
RonA

 

[zeppelin builder]

i'm a project manager in the oil and gas industry, and my current project is to deploy a DWS subsea to cut a 30" diameter riser as part of a platform decommissioning program. These things are very sensitive to wire speed and cutting force, but obviously benefit from being fully submerged in water to keep them cool.

A bit impractical to have in the workshop though !

did you also consider high pressure water jet with silicone carbide i once seen Oceaneering cutting 100 mm plate like butter does the redundant subsea line
get capped and left or removed

 

[eLuSiVeMiTe]

Had another lok at cast iron welding video & the diamond cut off discs the guy is banging on about are these https://www.lenoxtools.com/pages/lenox-metalmax.aspx
Claim theyre good for a 1000+ cut off operations & cheaper than abrasive cut off discs per cut.
RonA

Might grab some for work.

https://www.ebay.co.uk/p/2-X-Lenox-...0%26rvr_ts%3Da7e4e5031660a9cda6044e49ffff0eb2

 

[eLuSiVeMiTe]

Less sparks being a plus as I'm usually working in dry rooms full off wood and building materials.

 

[zeppelin builder]

cant see them being any good
they will be selling Diamond T next

 

[eLuSiVeMiTe]

cant see them being any good
they will be selling Diamond T next

From my perspective they should be workable.
Chippie so not heavy use,

Chopping the odd few bolts down, tile trim. Odd bit of rebar etc.

 

[Rig Pig]

did you also consider high pressure water jet with silicone carbide i once seen Oceaneering cutting 100 mm plate like butter does the redundant subsea line
get capped and left or removed

Long ago I worked on the development of the Claxton / UWG subsea severance tool, that was similar to what you are describing, uhp abrasive jet.

 

[JEZGUZ]

I watched the same series on Youtube, it was Keith Fenner repairing some hubs that had been messed about with, I'm being polite here, the disc he was using seemed to do the job nicely but you could probably do the same job with some 1mm discs, it might work out cheaper.