Calibrating Underweight Plates

[Sean Stangl]

I recently bought 12 "Standard Barbell" 45-lb plates off of Craigslist at a good price for a home gym. A calibrated scale is telling me that most of the plates are off by more than a pound, mostly in the negative direction, which is pretty unfortunate.

In another forum post, Rip says that underweight plates can't be fixed. But what if instead of striving for quality, I just did a shitty but sufficient job and called it a day?

I'm looking for some ideas on how to add weight to the plates. So far my best ideas are "slather on more paint" and "symmetrically superglue some weighty things to the inner rim, possibly washers".

In order of weight, plates are: 41.6 (43.2 x2) (43.6 x2) (44.0 x2) 44.6 (45.2 x3) 46.6

[Corrie]

Easiest way is to mark the plates and then try and set them up on the bar so they offset eachother. If they're only off around a pound each you could get some microplates and make it up that way too.

[Piers Finlayson]

I've used weights intended to balance car wheels successfully. They come with adhesive already applied. It needs quite a few of them thought to make up a pound or so - a strip in the UK (IIRC about 6" long) is 60g. In terms of balancing I've just tried to distribute them evenly.
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[Dave Paauwe]

I think the easiest would be to just sharpie or paint or etch the real weight onto the plates. You'll have to math some, tho.

[Rook]

Another idea is just paint a stripe on each set that weigh the same and also mark all of them with their actual weight.

Ie. the blue set is 43.2, red set is 43.6, etc,

How much does your bar weigh?

[Str8shutr]

Yeah you might want to check your bar. I got a new bar in, and decided to weigh all mine. New bar was 42.3, old SQ/DL bar was 43.6, and old BP/OHP bar was 38.5#s.

Now I need to go weigh my plates. Thanks.

[BareSteel]

Easiest way is to mark the plates and then try and set them up on the bar so they offset eachother.

This is the first priority, in my opinion.

Believe it or not, I would not do anything to try to add weight to the plates. As the OP suggested, it would probably be sloppy. If, after the matching that Corrie advised, there was still a major difference, then I'd try Rip's suggestion of drilling the heavier plate down.

At this point, you'll have a symmetrical load on the bar, but at a weight lighter than the listed weight. High precision, low accuracy. For calculation reasons, I'd probably still use the listed weights for my personal training log - with the understanding that the loads are a little off. Of course, you could bother with recalculation if you are a stickler.

** I looked at your exact weights. You already have four matches, or eight symmetrical plates. That leaves two that are kind of close, and then your oddball heavy (46.6) and light (41.6) plates to contend with. Good eye on weighing them!

[medwards]

Buy some half pound washers. Add as needed. Call it good enough.

[sasquatch]

Not adding any new information, but I weighed my plate and I had several plates that were off by ~ 6oz. I just put white duct tape on the plates that were off and used a permanent marker to write the true weight, and when loading the bar I pay attention to which plates are heavier, and make sure I don't put them all on the same side. For my 45lb plate that is off, I just add an extra collar which weighs 1/2 lb to the other 45lb plate. I wouldn't stress about making sure the weights are "true," just focus on making sure the weights are about even on either side of the bar.

[John Watson]

What kind of scales are you guys using? Digital bathroom scales, or something more elaborate?
I know the trick for using the scale in their more accurate human weight range, hold the plate or barbell while standing on the scale, then weigh yourself and subtract the weight.