E T
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Get some cobalt centre drills.I couldn't get the bloody lathe centre drill to do more than tickle it!
Get some cobalt centre drills.I couldn't get the bloody lathe centre drill to do more than tickle it!
Those calculations go out the window on a farm. You wouldn't believe what farm workers can break.An 8.8 grade bolt with a diameter of 18 mm and in double shear should not start yielding until subjected to a load of 188 tons. The same grade bolt, again in double shear may fail with a load of around 235 tons. Is the equipment being subject to high impact loads?
Or soldiers .Those calculations go out the window on a farm. You wouldn't believe what farm workers can break.
Ditto, I wouldn't be going anywhere near a lathe if I could buy off the shelf 18mm bar and drill a hole one end for a retaining pin with a washer welded onto the other.Does the bolt have to be tight to do its job, or can you get away with a sliding fit pin? Could make a nice pair of pins with circlips or roll pins for retaining...
Nope, if it was tight it wouldn't move as there's gaps between tabs, it's a mx silage grab, not overly heavily built really.Does the bolt have to be tight to do its job, or can you get away with a sliding fit pin? Could make a nice pair of pins with circlips or roll pins for retaining...
Don't know why I hadn't thought of that tbh, guess I was set on utilising the latheDitto, I wouldn't be going anywhere near a lathe if I could buy off the shelf 18mm bar and drill a hole one end for a retaining pin with a washer welded onto the other.
This is what I would do. I would be concerned that it is a shear bolt to save damage. Could you consult the manufacturers ? Proper shear bolts normally have a short threaded portion, just enough to get a locknut on. Might have been replaced by a normal partially thread bolt in the past as they are cheaper, bringing the shear point in line with a joint, which is not best practise in any case.Could you replace with longer bolts and use a spacer under the nut? Then you move the start of the thread away from the shear line, so all the shear is on the plain shank of the bolt.
Ditto, I wouldn't be going anywhere near a lathe if I could buy off the shelf 18mm bar and drill a hole one end for a retaining pin with a washer welded onto the other.
Its not breaking them every use or anything, this is maybe the 3rd or 4th I've swapped since we bought it maybe 10 years ago, but they've all gone at the thread start/end of shank.This is what I would do. I would be concerned that it is a shear bolt to save damage. Could you consult the manufacturers ?
If not, I would do as Agrosheild has suggested, and see how you get on. If still a problem use 10.9 grade bolts with the spacers.
Those calculations go out the window on a farm. You wouldn't believe what farm workers can break.
labour time to make a couple of pins that keep breaking gets expensive.I'd be tempted to use mild steel and see how long it lasts. Only £11.91 a metre so cheap as chips.
labour time to make a couple of pins that keep breaking gets expensive.
even if a bolt is £10 each, that's still cheaper than £40 for an hour of time to make a couple on a lathe. If you want to make them, they need to last a lot better than the original.