Square to round

[Ben88]

Ive never done a square to round but would like to know how it's done, I presume that you would be given the height, length, width & diameter and that it would be done in 2 halfs? I think i remember reading that you draw centre lines in the centre, draw a circle at needed diameter split half of the circumference into 12 equal parts same on other side of circle then draw your length & width of your square using your centre lines as reference with the circle in the centre on the square then join your radius marks to each corner cut out the diameter, then fold on each of those lines lust over 11 degrees each segment which should leave each side at 90 degrees. I imagine im very wrong????

 

[Maker]

There is lots of software to lay it out for you, though doing it on paper is more fun. I don't understand the method you're describing, but it doesn't sound right. This page explains it better than I can at this time of night.

 

[hotrodder]

Googling square to round triangulation will get you various guides on laying them out like the sheet metal world link already posted
Books like The geometry of sheet metal work cover pretty much everything about parallel line, radial line & triangulation methods of layout from basic stuff through to insanely complicated examples. If you check out the downloads/links section of the site you'll find some freeware, Tyharness for example offers Sq to round, segmental bend and frustum (right and oblique cones etc) calculators

 

[CRB]

GImages shows the way you are trying to describe. Basically correct except I always us 16 parts rather than 12.

Once you get the hang of it, it becomes very easy but it is handy to have three sets of dividers or similar.

 

[Paul G]

Whenever you see square to rounds in a development book or a computer program they nearly always make them in a single piece
or in two; but then they always fit on an A4 piece of paper which is not the same as working in metal, possibly expensive metal.

Folding in one is nigh on impossible, and not much easier in two; and also uses more material, hence I personally favour putting the
weld seams up the four corners. Easier to cut out the shape and fold, and much better from a weld distortion point of view.

Just my 2p

Paul G




Pics stolen from the net btw

 

[Ben88]

Sorry i did mean 16 i was'nt counting the corner lines, Is this just a simple way of doing it? its just that a lot of the stuff that i have read have been using true lines an using degrees an joining a-b b-c an stuff like that. I would assume that if you was sent a drawing to make a square to round it would have the length,width & hole diameter? And as for the height that would depend on the LxWxDia meaning if it was a big hole in the sheet the height would be shorter an if it was a small hole in a sheet it would be taller? I like the idea of welding it on the corner to stop distortion

 

[Maker]

And as for the height that would depend on the LxWxDia meaning if it was a big hole in the sheet the height would be shorter an if it was a small hole in a sheet it would be taller?

They would specify the height too, as it's not related to the other dimensions.

 

[Paul.]

I prefer to draw out my developments the old fashioned way, obviously cant deny that software is quicker but seems like cheating to me, the best place to put the joints will vary according to the shape and purpose of the finished job, corner joints may be harder to clean up on the inside for example on hygienic / food applications, this one I made in one piece http://www.mig-welding.co.uk/forum/threads/square-to-round-hopper.26339/

And here is a small one in mild steel I made in two pieces
http://www.mig-welding.co.uk/forum/threads/another-transition-piece.51001/

 

[mike os]

here is my first effort a few weeks ago... http://www.mig-welding.co.uk/forum/...t-lofted-dust-collection-port-in-sheet.57293/

 

[Ben88]

But if your job is say....L1000xW500x160 hole diameter then you would have a 1000x500 sheet you would draw 160 dia circle in the centre of the sheet, split each corner of the circle into equal parts (6-8) join to each corner then cut in half corner to corner. I can't see any way of changing the height in this method?

 

[CRB]

You MUST have a height. Impossible to do it without, and they/ you are also assuming centrally located apertures.

The method you describe will not give you what you require. a-b, b-c as in Post6 will.

 

[Ben88]

Thanks for the help i really appreciate it once i have mastered this what shape would you recommend looking at making next to build my skills? I can make a cylinder, cuboid, cone & pyramid

 

[CRB]

A transition between two cones would be fun

The fun you can have is endless

It is much easier to SEE someone do the job. I watched an old had do a square to round twice and it all fell into place, one was concentric the other was not. The same operations apply, just a little different.

 

[Ben88]

Yeah it would be great if i had someone to help me learn how to do these things, hopefully i'll get a start somewhere soon that can expand my knowledge im getting a bit board with trays, steps, tables & channels an things like that.

 

[CRB]

Had you asked in 1976, I would not have learned it yet, but I lived in Bury. A lot of use that would be.

Take some time and work slowly through the instructions, it will all fall into place. A, b, c is the way. Though it sounds like gobbledegook, it is better to truly understand what you are doing, than to speed read, hoping it all works out.

Good luck.

 

[ukracer]

A transition between two cones would be fun

The fun you can have is endless

It is much easier to SEE someone do the job. I watched an old had do a square to round twice and it all fell into place, one was concentric the other was not. The same operations apply, just a little different.

@doubleboost good project for a Sunday night cap

 

[CRB]

@doubleboost good project for a Sunday night cap

I will help out with the live translations, and the girls can sign.

 

[Maker]

But if your job is say....L1000xW500x160 hole diameter then you would have a 1000x500 sheet you would draw 160 dia circle in the centre of the sheet, split each corner of the circle into equal parts (6-8) join to each corner then cut in half corner to corner. I can't see any way of changing the height in this method?

I'm still not entirely sure what you mean but if you draw 160mm dia circle, once you've cut and folded it all it won't be flat on top, neither will it be perfectly circular, nor 160mm across the opening as far as I can tell.

 

[Paul G]

Ben, what tools do you have? You will need a set of dividers and a set of trammels to mark out a square to round.

Steel rule, tape measure, dot punch and a scriber will be handy as well as a sheet of metal.

If your up for it I'll run through it a stage at a time.


Paul G

 

[Tinbasherdan]

Christ it's bad that the sheet metal worker here is evidently the rustiest at doing square to rounds! Need to have a bash again sometime, it's been a couple of years since I had to do one last