Chain Hoist

As I'm in the process of bringing home my J&S540 grinder (no, I haven't got it home yet -nearly there!) I had to upgrade my lifting
tackle. My existing block & tackle was only rated at 1/2t while the grinder weighs 3/4t. I was half tempted to give it a try, but thought I'd do the right thing and get some bigger lifting gear. I bought a 1t block & tackle from ebay -looks like the kind of thing machine mart sell from the picture (cheap & cheerful, but it won't get used much). I was rather surprised to find that the chain on the 1t unit was smaller than my old 1/2t unit -and the quality of welding on the chain links was very poor.
Has chain got much stronger, or is there something badly wrong here. Perhaps the FOS has been dropped signifficantly -the leaflet with the new block & tackle suggested it had been tested to 1.5t. For the record the chain links on the old unit was 6.4 dia while the new unit was 5.4 dia -but of course this is little help as I don't know the grade of steel used.
Regards
Kevin
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On Mon, 01 Aug 2005 20:31:49 +0100, Kevin Steele

If you had a snatch block of suitable size, your 1/2t hoist would be OK by connecting both ends of the hoist to the lifting beam at the top, and the snatch block to the grinder. Each fall of chain would be carrying 3/8t.
You could even make a snatch block out of a wheel, two pieces of bar and a couple of bolts. No doubt someone could calculate the size of plate and bolts required, but if you erred sensibly on the side of caution (say 10mm plate and M16 bolts with 25mm or more of metal between the edge of any holes and the edge of the plates), you could save some money and still do the job safely.
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