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U-bolts. Is bigger better?

SolarBell

NAXJA Forum User
Location
Wheat Ridge, CO
With a new set of springs, a 1/2" thick top plate, and a 4* shim, the u-bolts I had on hand are too short. I can get an off-the-shelf set of u-bolts that are long enough but are 9/16" in diameter so I'd have to drill out the top plate. Or I can order a set of custom ones that are longer but are still 1/2" diameter and cost more.

Is there a good reason to go to the 9/16" u-bolts or it is not worth the hassle of drilling everything out?
 
You're opening up 8 holes 1/16" in diameter larger than they already are.

Hardly seems like a hassle to me.

Though you don't normally hear of people breaking u-bolts.
 
With a new set of springs, a 1/2" thick top plate, and a 4* shim, the u-bolts I had on hand are too short. I can get an off-the-shelf set of u-bolts that are long enough but are 9/16" in diameter so I'd have to drill out the top plate. Or I can order a set of custom ones that are longer but are still 1/2" diameter and cost more.

Is there a good reason to go to the 9/16" u-bolts or it is not worth the hassle of drilling everything out?

Just realise that there's a point of diminishing returns - although I doubt that 1/16" (0.0625") is it.

Since you've got to remove material from the plate, you're making the plate incrementally weaker in exchange for the stronger U-bolts.

THUMB RULE - I like to leave at least 0.75d material between the hole and edge of the plate, all directions, when planning where to put screws. d is the nominal diameter of the screw (since 9/16" = 0.5625", then 0.75d would be 0.4219", or 27/64". Most prefer to leave d room, but I haven't found that to be generally necessary, except in very-high-strength applications.)
 
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