Static / Dynamic loads for drawer slides

[Robert Reece]

What is the "static" load referring to. It seems like a drawer slide is by definition dynamic. I must be missing something.
For example a Blum Tandem 568 slide has a 110# static, 125# dynamic. Are they saying I can keep 125# in it as long as I don't move the drawer?

[Stephen Saar]

My understanding of the slide ratings was that the static weight was the amount of pounds in force the slide was rated for directly perpendicular to the slide, i.e. 110 pounds of downward force, or you can load the drawer up to 110 pounds worth of material. The dynamic weight I believed meant that the drawer could take additional force for a short period of time. i.e. you dropped a 10 pound item on the slide with the slide already supporting 100 pounds worth of material. When the 10 pounds hit it generates 25 pounds of force but only for a fraction of second, thus the slide can take the extra wight but only for a short period of time. I'm not positive on this though, I haven't ever read any official testing methods that these companies use when determining the weight ratings, but that would have been my assumption.

-Stephen

[Jamie Buxton]

I think you have it backwards on the Blums. Generally dynamic load ratings are lower than static, not higher. I've understood this to mean that the slide will not collapse if you put the static load on it, but if you want to run it back and forth the 10,000 times or whatever the KCMI specs, you can only meet that with the dynamic load.


... Ah... According to the printed catalog from Woodworkers Hardware, the Blum 568 has a 100 lb dynamic rating, and a 125 lb static.

[Jeff Qualmann]

Jamie's got it right. The dynamic load is generally less then the static, as it relates to the weight supporting ability under normal situations while being cycled. Slide manufacturers generally cycle test their slides using a weight loaded drawer to meet established industry standards. If they can't meet the cycle test the required number of times, they don't pass the standard.

Since we all expect our drawers to to be opened and closed in use, the dynamic weight rating is the one to pay attention to.

[Joe Jensen]

Jeff and James are right, static means stationary an dynamic means in motion. Static should always be higher. I was just reviewin the specs for some Blum tandems and they showed the loads at different places in the drawer so perhaps if the spec for static is lower than dynamic, they may be showing that load off center in the drawer. That is how they showed on of the specs for that Tandem.