[How do I?] Square Hole ?

[Shiseiji]

Last idea. Use the mag drill to drill the up-rights for round holes. Weld a nut inside the end of each cross piece. A uni-strut 3/8" nut may fit just about right inside the lateral tubing. Set the nut ~ 1/4" back from the tubing end and that will allow a little flex to correct minor out of square but you should be able to get it where you want it on the 2" tubing. You could probably do OK with 4 just a little more than a tack. Put the thread in and stick weld it so you can just poke the electrode in. Connect with all thread. Tighten till it's flush and square.

You will need left hand thread in the inner side for the second to last horizontal set so you have right hand thread in both end uprights to minimize "opps" and probably some fine tuning on the rod length so it will pull flush. You can cheat for the all thread by using turn buckles and cutting off the eye. You will only need a tap to make the few left hand nuts. You could test this less expensively to see how it goes before purchasing other $$ tools.

Oh, just had this as I hit [Save] maybe the |Good | Quick | Cheap | is to just tie most of it together with all-thread. Can you get away with a small access hole either in the underside end of a horizontal or if shelves are going on, put it on the top and cover it with a shelf. There's the access to a coupler if needed. Will a shelf bridge the connection between horizontal pieces and the uprights?

 

[RedOak]

Last idea. Use the mag drill to drill the up-rights for round holes. Weld a nut inside the end of each cross piece. A uni-strut 3/8" nut may fit just about right inside the lateral tubing. Set the nut ~ 1/4" back from the tubing end and that will allow a little flex to correct minor out of square but you should be able to get it where you want it on the 2" tubing. You could probably do OK with 4 just a little more than a tack. Put the thread in and stick weld it so you can just poke the electrode in. Connect with all thread. Tighten till it's flush and square.

You will need left hand thread in the inner side for the second to last horizontal set so you have right hand thread in both end uprights to minimize "opps" and probably some fine tuning on the rod length so it will pull flush. You can cheat for the all thread by using turn buckles and cutting off the eye. You will only need a tap to make the few left hand nuts. You could test this less expensively to see how it goes before purchasing other $$ tools.

Oh, just had this as I hit [Save] maybe the |Good | Quick | Cheap | is to just tie most of it together with all-thread. Can you get away with a small access hole either in the underside end of a horizontal or if shelves are going on, put it on the top and cover it with a shelf. There's the access to a coupler if needed. Will a shelf bridge the connection between horizontal pieces and the uprights?


View attachment 377784

Yes, shaping the shelves and the final edge banding is where we really add some value to this project. Normally, we would build the whole damn thing out of laminated hardwoods, but the [repeat] customer wants a wood/metal rack for his incredibly expensive gear...I guess that it will help him sleep better at night...but, regardless, he's paying the freight, so there you go.

This is also a nice idea, but it's the "tightening" part of this design that has me scratching my mellon a bit. Does the "access" you mentioned mean a hole in the horizontal/lateral members that will accommodate a wrench? If so, all of the hardware involved in the structural fastening of the rack would have to be fairly small, no? The horizontals in the working design are only 1" x 1" OD.

I really appreciate everyone putting their ideas into words for us.

EDIT: We have a supplier in Ohio who would love to supply us with a bunch of fairly heavy duty polyethylene "plugs" that would fit tightly into the ends of the 1" x 1" square horizontal members. An enhancement to this idea might be to employ longer pieces of all-thread to effectively reduce the number of structural connections. The "plugs" I just described could be bored very accurately, via a centering jig and the mag drill, and used to keep the all-thread centered and, more importantly, well away from the inner edges of the horizontal members.

 

[Firstram]

I have been following this thread from the beginning but I'm sure I have missed some posts, that being said...

I understand this is a repeat customer and you want to keep that relationship good. It sounds like they trust you to provide a quality product without micro managing when it comes to your woodwork. Why would they try to force inappropriate techniques in a medium they don't understand. It sounds like their expertise is with the expensive item sitting on the shelf, not the shelf itself.

There is no need or benefit to mortice and tenon a welded structure. Passing the the shelf support through the legs will not be any stronger than welding nor will it stop the structure from distorting when it is welded. Welding a simple cube can be difficult to keep square, flat and clean, just like woodwork, there are tricks that become rote. Adding washers to fill the holes will only cause more distortion and grinding marks to fill with spot putty. Thin wall tubing is prone to walking all over the place when welded and has a very tight corner radius which is very difficult to maintain when grinding.

If you have never fabbed a powder coat quality steel structure then your first project should not be one that is being sent to a picky client. Even if it gets paint, the welds need to be very consistent to inspire confidence. Get a quote (+10%) to have this stand TIG welded (zero inside corner grinding) by someone who does this every day. As far as doing everything in house, 37 years in the trades have taught me to focus on what I'm good at and not try to do everything.

Have a conversation with your client explaining your desire to give them a product you can both be proud of.

If you are sending them a flat packed DIY assembly then it's a different story.

 

[Weldingrod1]

+1 on that... very little strength gain from the small tube inside the big one. It's easy to get a full tube cross section in the weld. Actually, it's hard to get that small a weld area ;-)
Is there some functional reason for the through hole provided by the small square?

Sent from my SM-G892A using Tapatalk

 

[jwmelvin]

[mention]Firstram [/mention] I couldn’t agree more. I guess the only thing I’d say about cutting the verticals is that it would make for quick assembly and alignment during welding, if the holes were precisely cut. But they won’t be. This whole thread is befuddling. But it’s kind of entertaining to watch it unfold.

 

[RedOak]

[mention]Firstram [/mention] I couldn’t agree more. I guess the only thing I’d say about cutting the verticals is that it would make for quick assembly and alignment during welding, if the holes were precisely cut. But they won’t be. This whole thread is befuddling. But it’s kind of entertaining to watch it unfold.

I'm not sure about where the word "befuddling" comes from? It's just a discussion about a "custom" project we were asked to do for a good repeat customer. I apologize if this thread has caused anyone anxiety...In fact, I don't even know what to say/write about that, so I'll simply press on with the civil discussion...

 

[RedOak]

+1 on that... very little strength gain from the small tube inside the big one. It's easy to get a full tube cross section in the weld. Actually, it's hard to get that small a weld area ;-)
Is there some functional reason for the through hole provided by the small square?

Sent from my SM-G892A using Tapatalk

How does one argue with a structural engineer who builds bridges for a living about the design of an A/V/D rack? I was thinking that this was covered earlier in the thread. As I mentioned before, the guy designed the rack, showed me the drawing and asked me to build it for him. That's not to say that the design couldn't be modified or enhanced in some way, but I'm here to "think out loud" with the good folks who've been kind enough to share their thoughts and ideas with a novice metalworker who happens to have a long history in woodworking.

 

[RedOak]

I have been following this thread from the beginning but I'm sure I have missed some posts, that being said...

I understand this is a repeat customer and you want to keep that relationship good. It sounds like they trust you to provide a quality product without micro managing when it comes to your woodwork. Why would they try to force inappropriate techniques in a medium they don't understand. It sounds like their expertise is with the expensive item sitting on the shelf, not the shelf itself.

There is no need or benefit to mortice and tenon a welded structure. Passing the the shelf support through the legs will not be any stronger than welding nor will it stop the structure from distorting when it is welded. Welding a simple cube can be difficult to keep square, flat and clean, just like woodwork, there are tricks that become rote. Adding washers to fill the holes will only cause more distortion and grinding marks to fill with spot putty. Thin wall tubing is prone to walking all over the place when welded and has a very tight corner radius which is very difficult to maintain when grinding.

If you have never fabbed a powder coat quality steel structure then your first project should not be one that is being sent to a picky client. Even if it gets paint, the welds need to be very consistent to inspire confidence. Get a quote (+10%) to have this stand TIG welded (zero inside corner grinding) by someone who does this every day. As far as doing everything in house, 37 years in the trades have taught me to focus on what I'm good at and not try to do everything.

Have a conversation with your client explaining your desire to give them a product you can both be proud of.

If you are sending them a flat packed DIY assembly then it's a different story.

It's funny you should mention mortise and tenon because I think some of the trestle tables we've built for this fellow in the past may have influenced his metal design concept.

As for having a conversation with the designer, that's certainly going to happen...at some point. I'm here as a novice looking for ideas. The project was based on the understanding that it's not at the top of our priority list. The designer/customer understands that we're not metal workers, so he's given us a lot of leeway on the scheduling front...but, as I mentioned very early on, once fabrication begins, I want to give the customer an estimate on when it will be completed. That's really all the urgency that's involved with this, so please, let's just continue with the civil discussions.

 

[ErichKeane]

Ah, the mention of tressle table makes me think... Is the "through" post a design element? The welding a butt joint is going to be easiest/most effective, but doesn't have the "post sticking out" design element.

Perhaps that is the confusion? @Firestram?

 

[jwmelvin]

Sorry, i shouldn’t have said befuddling and I did not intend it as an insult; I apologize. I take issue with both the stated design and your approach to fabricating it.

The stated design doesn’t make much sense. It has certain benefits, but those are only achieved if the holes are cut accurately. The industry has solved this problem (computer-controlled cutting methods), but you want to find a different way to do it. Your way loses the benefit of the holes (precise alignment). Using a standard fabrication approach (fixturing and welding) would eliminate any need for the holes. And once welded, the holes do not offer much visual impact. If one really wanted crisp joints, the holes (with minimal welding) could be warranted.

An engineer that works with metal would understand that the design would be better without cutting the uprights. They are stronger that way and the fabrication is more straightforward.

I remain interested in following your approach. It’s of course true that many approaches would lead to an acceptable result.