Should I be concerned with racking in this standing desk design?

[Torrey Cazalas]

I’m building a 44” tall maple/steel standing desk with steel H frame legs (photo below) that measure out to be 39.25” tall and 24” wide. Legs are made out 1.5”x1.5” steel tube.
The table top will be 48” x 28” x 1.75” maple butcher block top and there will also be a 1.25” maple panel/lower shelf fastened to the lower leg rails. Lastly, legs will be on 2-3” casters.
So my question- Is there any potential for racking with the legs being so tall or will the fastened table top and lower shelf prevent that? I might also be adding drawers under the table making it further top heavy.
Any input is appreciated!

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[Dan Friedrichs]

In terms of racking, I think you have belt, suspenders, and 5-6 more pairs of suspenders :) If you look at adjustable standing desks, you'll see that most only have a single legs on each side - between that and whatever slop exists in the raise/lower mechanism, they're still stiff enough. So in your case, I definitely wouldn't worry.

Are you going to be using this for something heavy-duty, or just normal "desk" work?

[Torrey Cazalas]

In terms of racking, I think you have belt, suspenders, and 5-6 more pairs of suspenders :) If you look at adjustable standing desks, you'll see that most only have a single legs on each side - between that and whatever slop exists in the raise/lower mechanism, they're still stiff enough. So in your case, I definitely wouldn't worry.

Are you going to be using this for something heavy-duty, or just normal "desk" work?

It's for someone else. If I had to guess its normal desk work.

Someone on another forum mentioned: "If the lower shelf is firmly attached it might be enough. If it’s just screws into the top holding it then it will rack, screws into wood won’t resist that much leverage."

^^this got me thinking.

[Rod Sheridan]

Yes, that's a design that can collapse when the forces are in the long direction of the table.

If you visualize putting it upside down on the floor, push on the legs and watch them pull the screws out of the wood. You've built a 40" long pry bar.

A rear modesty panel would prevent racking...............Regards, Rod.

[Jamie Buxton]

Yes, that's a design that can collapse when the forces are in the long direction of the table. If you visualize putting it upside down on the floor, push on the legs and watch them pull the screws out of the wood. You've built a 40" long pry bar..

Yes, in concept. But his screws are going into maple which is 1.75" thick. Even with a 40" pry bar, pulling the screws out of the wood will be extremely difficult. Perhaps you can snap the screw, but you can fix that by using quarter-inch lags.

[Jamie Buxton]

I'd be more concerned with hygroscopic expansion. The maple is going to grow and shrink across the grain. The steel will not. I'd oval out the holes through the steel out at the ends. I'd snug down the screws through those holes, and then back 'em off a half turn or so. That gives you a sliding joint. The screws in the middle of the span can be tightened fully, so the whole leg doesn't slide around.

[Torrey Cazalas]

I'd be more concerned with hygroscopic expansion. The maple is going to grow and shrink across the grain. The steel will not. I'd oval out the holes through the steel out at the ends. I'd snug down the screws through those holes, and then back 'em off a half turn or so. That gives you a sliding joint. The screws in the middle of the span can be tightened fully, so the whole leg doesn't slide around.

Thanks for your response. I did plan to slot out to allow for movement as you mentioned. The top will be an edge grain glue up, bottom shelf will be face grain.

Following the protocol you suggest, do you think adding a cross brace on the lower rails (see photo) where the lower shelf will be is necessary or could I get away without it?

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[Jamie Buxton]

That low cross brace doesn't do a whole lot to reduce the racking -- some, but not a lot. What would help a whole lot more is triangularization. Put a brace from a leg up to the maple top. The brace might run up at a 45 degree angle. The triangle formed by two pieces of steel and one of maple is incredibly strong.

[Torrey Cazalas]

That low cross brace doesn't do a whole lot to reduce the racking -- some, but not a lot. What would help a whole lot more is triangularization. Put a brace from a leg up to the maple top. The brace might run up at a 45 degree angle. The triangle formed by two pieces of steel and one of maple is incredibly strong.

That's a good idea, though i'm afraid it'll be too distracting to the minimal look I'm aiming for.

[Mark Daily]

I don’t think you’ll have any problems with your design. The shelf should provide ample “rack-prevention”.

If not, can you add that steel connecting bar in the photo beneath the shelf?

[Jamie Buxton]

That's a good idea, though i'm afraid it'll be too distracting to the minimal look I'm aiming for.

The brace doesn't have to be long. A ten inch long brace would do a great deal to stiffen the table against racking. It would be under the table top, and not very visible.

Or you could include that piece of steel under the wood shelf at the bottom, and put the angled brace between the leg and that piece. It would be out of sight underneath the shelf.

[johnny means]

This style is all the rage in bars and restaurants right now. Your design isn't bomb proof by any means. You could certainly pancake it, if you tried. That being said, it'll be plenty sturdy for regular duty. Your screws will actually be the weak link on the chain. We go with HeadLok screws to provide plenty of bite and a pretty much unbreakable connection.

[mreza Salav]

I think it will be strong (given the number of holes I see for the lag bolts).
Wooden lower shelf provides very little (if any) support against racking. A metal bar as you have shown in one of your pictures will make it plenty strong.

[johnny means]

A lower stretcher is nice for propping up one foot for a change in position or as a footrest for stool sitting,.

[Torrey Cazalas]

This style is all the rage in bars and restaurants right now. Your design isn't bomb proof by any means. You could certainly pancake it, if you tried. That being said, it'll be plenty sturdy for regular duty. Your screws will actually be the weak link on the chain. We go with HeadLok screws to provide plenty of bite and a pretty much unbreakable connection.

Lol. Ya, not looking for bomb proof. Simply needs to be enough to conduct "office work" and mobile capability via casters.

I'm not familiar with HeadLok screws. What separates them from other fasteners for this application?

[Frederick Skelly]

Lol. Ya, not looking for bomb proof. Simply needs to be enough to conduct "office work" and mobile capability via casters.

I'm not familiar with HeadLok screws. What separates them from other fasteners for this application?

From Google LINK (https://www.google.com/search?q=headlok+screws&oq=headlok&aqs=chrome.1.69i57j0l3.5219j0j8&client=tablet-android-samsung&sourceid=chrome-mobile&ie=UTF-8#lbl=OVERVIEW&pie=plaji-i)