You are correct when you say the answer is "No." 840lbs would be correct only if the weight were evenly distributed to each caster(all the time).
According to specs, a U1 weighs ~500lb. If, for example, the weight were evenly distributed, 4 casters could(without a safety margin) be 125lb rated.
If you were to assume that 60% of the weight(my guess) was in the back(& the weight was evenly distributed bass end to treble end & level floor),
you would need 150lb in the back & 100lb in the front.
Did you ever notice that the front casters are usually smaller? They don't need to hold as much of the weight(& they look nicer).
You have probably seen the upright in which a rear caster is broken from less than careful movers.
In that situation(or even an non-level floor), more of the weight is placed on the caster making contact.
Isn't math fun!
You engineers can now let us know about weight ratings as a % of actual as a safety factors.
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John Gallen
OWNER
1040 Pianos
S Windham CT
860-428-6045
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Original Message:
Sent: 02-13-2020 08:16
From: Charles Rempel
Subject: BETTER casters
210 lbs apiece should yield a total of 840, no? I don't know what a U1 weighs off the top of my head, but certainly less than that. I don't know if they're a good solution, but they should be fine from a weight standpoint.
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Charles Rempel
Dampp-Chaser Corporation
Hendersonville NC
828-692-8271
Original Message:
Sent: 02-12-2020 17:00
From: Roger Gable
Subject: BETTER casters
Jim,
The load rating of those casters are insufficient for a Yamaha U1. Also, I'm not sure how you would attach them to the toe blocks.
Roger
Original Message------
FYI, after talking to a woodworker who has Rockler's version of the retractable casters on heavy work tables in his shop, I ordered a set of these casters. I also ordered a set of the plates which allow you to remove the casters with no tools...just bend down and pull them off...which might make sense in the install. I have permission to experiment with this on the U1 I mentioned in the original thread on this topic.
I will report.
I ordered Rockler's version of this, as the Amazon one James linked seems to be wimpier as well as less expensive.
https://www.rockler.com/rockler-workbench-caster-kit-4-pack at the bottom of the page are the additional plates that allow you to pull the caster off if that makes sense in your situation.
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Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026
Original Message:
Sent: 02-11-2020 16:50
From: Jim Ialeggio
Subject: BETTER casters
Hmmm...might work. Leave the U1 casters on. Place these only on the front and back of the box, rather than on the back and the toe blocks(or whatever you call them). Since they are only engaged when moving the piano, if they are slighlty wimpy it might not matter. Someone want to be the guinea pig?
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Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026
Original Message:
Sent: 02-11-2020 16:36
From: James Kelly
Subject: BETTER casters
I just came across these casters that might be worth taking a look at . Some hefty lag bolts into beams on the back botton and front bottoms may work and avoid the need for outriggers.
https://www.amazon.com/Workbench-Retractable-Urethane-Workbenches-Machinery/dp/B07DX7HL9G?ref_=ast_sto_dp
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James Kelly
Owner- Fur Elise Piano Service
Pawleys Island SC
843-325-4357
Original Message:
Sent: 02-11-2020 15:13
From: Steven Rosenthal
Subject: BETTER casters
Ed, thank you! My mistake was not considering the height of the casters till after I'd installed the outriggers. Lesson learned.
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Steven Rosenthal
Honolulu HI
808-521-7129
Original Message:
Sent: 02-11-2020 08:40
From: Ed Sutton
Subject: BETTER casters
As Steve said, just raise the outriggers a little higher on the side of the piano, and the pedals and keyboard will be at the normal height. A remarkably elegant solution!
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Ed Sutton
ed440@me.com
(980) 254-7413
Original Message:
Sent: 02-11-2020 06:38
From: Terrence Farrell
Subject: BETTER casters
Steve R.'s solution with the outriggers is excellent! The other thing I thought of is to install nice double-wheel Darnels and then place a platform of appropriate height under the bench and pedals so the pianist sits at an optimal height and the pedal height feels normal.
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Terry Farrell
Farrell Piano Service, Inc.
Brandon, Florida
terry@farrellpiano.com
813-684-3505
Original Message:
Sent: 02-10-2020 06:58
From: Andrew Warden
Subject: BETTER casters
Anyone know of smoother-rolling small casters for upright pianos? Customer doesn't want dolly and doesn't want bottom of piano any more than 1 1/4" (5.8cm) off the ground (for pedaling comfort), but wants to be able to move piano around living room hardwood floor with minimum fuss. Front leg structures are not wide enough for routing out oversize wheel wells. The original casters were brass with ball bearing rings and they scratched the floor and finally collapsed. It's a pretty big upright: Wendl & Lung (Hailun) model 122-Univ., serial number 13290.
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Andrew Warden
Evanston IL
224-420-1773
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