# How to compute the weight of a digital piano, included play pressure? [closed]

I am researching ways to build my own recording studio desk out of wood, and may be interested in creating a drawer to hide and pull out my 24-pounds (12 kgs) digital piano from under the desk top. However, knowing that I will not only lay the piano on the drawer but also play it, I would like to take into account also the weight of the hands pushing the keys when considering which drawer slides set to buy (and I might get emotional and press a bit more than what is needed...). However, I cannot find any information on how much weight is usually taken into account when designing "digital piano drawers" on the web.

How much should I add to the piano weight to achieve a good degree of safety on the structure when playing?

• I'm not convinced, that a weight equivalent will be sufficient. Keys work as levers, and the moment of force surely depends on the distance between supporting point and the point, where you press. SInce the distance is a multiplying factor I would go for a significant margin of safety. – guidot May 7 '18 at 15:26
• I'm voting to close this question as off-topic because it is more of an engineering question than a musical one. – Richard May 7 '18 at 22:34
• Thank you, Richard. I would have asked somewhere else, but I figured the kind of stress the keys are subject to would be more familiar to a musician than an engineer. If my reasoning was incorrect I apologize. – phagio May 8 '18 at 16:33

Well, the weight the good stage piano tables are built for is usually around 60kg. From my experience, this is really the weight you aim for if you got hammer action on your keys.

Why I think this makes sense? Well, the pianos themselves weigh around 20--25 kg. Then there's the players. Imagine an 80 kg player, then the most he can put in statically is 80 kg, dynamically about twice as much, but this would involve him lifting his feet and butt in the air, which he does not, right? You play using your shoulders, and this should be roughly a quarter of the available strength, i.e., about 40 kg.

• Dear downvoter, note that if you give me -1 and don't tell me what's wrong, it doesn't make any sense – yo' May 8 '18 at 15:31
• Thank you yo'. I like the reasoning behind the computation, although maybe a bit "rough". Just for personal research, do you have any reference about the "general 60kgs support" of the average piano stand? Specific brands or types of digital pianos you have in mind? – phagio May 8 '18 at 16:42
• @phagio Well, I have BESPECO (similar to SH100) which has 60kg. Some stands are stronger, e.g. 105 kg for double stand, or even 180 kg single stand. However, I have never had any issue with my stand, and I suppose the extended capacity is partly for people possibly sitting on the stand or for rough conditions such as concerts with aggressive visitors. – yo' May 8 '18 at 17:42

Put some scales - digital, maybe, on a table. rest the keyboard on them, possibly with some support between, so you can see the display. Play the keyboard. Note (sic) the reading, subtract the weight of the support, add 50% for safety. Voila!

• Personally I would add at least 50% for safety, if not 100%. – Todd Wilcox May 7 '18 at 15:23
• @ToddWilcox - point taken, you can't beat a good margin. Although what I'd do is have a couple of removable legs ()like I've done in the studio), so the weight is somewhat academic. – Tim May 7 '18 at 15:43
• @Tim Note that the scale will still measure the average over some time. And even short time as 0.5 s can be 4 notes played. This means the scale will typically read much lower than what you need. – yo' May 7 '18 at 18:08