[How do I?] Square Hole ?

[RedOak]

If you had a mill + lathe I would think you might be able to make a 'shear' tool easily for the washers. Just buy some off-the-shelf non-zinc-coated washers about 1-5/8" round, then turn a tool to hold the washer, and another side to punch it through with a bolt... Probably want to make it out of 4140 HT so that it lasts 50x, but this might be the way to go if getting them made is expensive. Though, getting these tools made might be expensive unless you find a hobbiest to make it cheap.

Hey, Erich, would the square punch or knockouts made by companies like Greenlee work on some thinner material (like 0.065)? If so, this could be a possible alternative to having those custom washers subbed out. In other words, we cut our own squares out of a strip of 0.065 mild and, afterword, use the mag drill to create the same type of washer. Hmmmm...

 

[ErichKeane]

Hey, Erich, would the square punch or knockouts made by companies like Greenlee work on some thinner material (like 0.065)? If so, this is is a possible alternative to having those custom washers subbed out. In other words, we cut our own squares out of a strip of 0.065 mild and, afterword, use the mag drill to create the same type of washer. Hmmmm...

If one is made, probably! I wasn't aware of those, but they seem to be basically what I was thinking of! .065 is only about 14 gauge steel, which those claim to be able to work with.

That might be just the ticket! You MIGHT be able to find fender washers of the right OD to save you drilling, but that would work I would think.

 

[RedOak]

Sounds like it would work to me! Though if the frame is to be entirely welded, could you just use round-tube to go through the 2x2, then weld square tube over it? Might be costlier thanks to two pieces of material (though, the round tube doesn't actually have to go all the way through...), but might be easier. Similar to the squaring-it-up-with-wood idea above.

Yeah, that's another possibility, but the custom washer idea has me really thinking about using the square horizontals specified by the design again. In other words, the "square washer" concept seems like an idea where we wouldn't have to worry about deforming the 2 x 2 x 0.065 and we get to stick with square tubing all the way around...which is clearly what the customer wanted to begin with.

 

[RedOak]

Another upside of cutting these custom washers out of 0.065 mild steel is that it keeps the washers and the uprights at the same thickness, which is conducive to consistent welding. As I mentioned before, I'm no master welder, so welding steels of the same thickness should add to our chances of a good result.

 

[ErichKeane]

Yep! Only gotcha here is going to be to make sure you drill 'centered' around the square. I might consider an order of operations as:

1- Set the mag-drill (or drill press with the material locked down, if you have one, since it is now just a piece of metal), drill a 'small' hole.

2- Use the punch tool, centered around this 'small hole' (leaving the mag drill in place) presuming the punch has such of a centering fixture.

3- Use the annular cutter to drill the circle (and repeat!).

 

[deakin]

I'm not sure if you saw the post with this spec in it or not, Deakin, but the tubing being used for the uprights in the customer's design is only 0.065" in thickness. It's already been cut to length from 24' sections, so it's what we're going to be using. The horizontal material, on the other hand, has not been chosen, which is why I came to this beginner's forum. I'm no machinist, but I've already been warned that 0.065" thick mild steel deforms quite easily under a press. I also believe that the theme of the conversation has changed to making use of the rather expensive mag drill that we invested a lot of hard-earned into. Thanks for the post.

i won't deform after (in your case) you make a hardwood plug to slide in and support it

 

[RedOak]

Yep! Only gotcha here is going to be to make sure you drill 'centered' around the square. I might consider an order of operations as:

1- Set the mag-drill (or drill press with the material locked down, if you have one, since it is now just a piece of metal), drill a 'small' hole.

2- Use the punch tool, centered around this 'small hole' (leaving the mag drill in place) presuming the punch has such of a centering fixture.

3- Use the annular cutter to drill the circle (and repeat!).

I’ve been thinking about the same thing, Erich. Question: How does one use a manually operated knockout tool, like a Greenlee, and ensure that the “square” is centered in the subsequent hole cut by a mag drill?

My thoughts are that a centering jig would have to be employed that secures both the mag drill and the work piece. We’ve done something like this before, but never with anything other than cutting circles.

It occurs to me that each “washer” will have to come from a standardized piece of steel. That is, once the square has been “knocked out” of the steel strip, that section must be cut off of the strip in a uniform length each and every time to form an “outer square” that will fit nicely into the jig.

 

[ErichKeane]

I don't have a great idea on how those greenlee punch tools work. And the accuracy here is really going to matter.

 

[RedOak]

I don't have a great idea on how those greenlee punch tools work. And the accuracy here is really going to matter.

Yes, good point. Regardless, the square holes formed in Step 1 of the proposed procedure will have to be centered fairly precisely in their own right, aye?

 

[ErichKeane]

Yes, good point. Regardless, the square holes formed in Step 1 of the proposed procedure will have to be centered fairly precisely in their own right, aye?

Yes, exactly. Some of those punch tools work with a center bolt that squeezes two dies together, I'd you had that style, you could use a hole drilled with the mag drill (then not moving said drill!) to center it.