Math needed for welding - Page 3

1. Re: Math needed for welding

Originally Posted by Country Metals
You wouldn't believe how many engineers are completely astonished that I can figure out the size of a blender shaft with a piece of wire. Obviously there is a margin of error due to standard is metric sizing, but all I do is run a piece of thin wire, flat baler string, piece of paper etc around a shaft, mark the same spot, flatten it out, measure between the 2 points, divide by pie, and you have your shaft diameter.... Now this method is very very accurate because 1/16" off actually measures .196" between points. Obviously it won't do thousandths, but if you need to know if it is 3 15/16" or 4" shaft. 3 15/16 would measure 12.37" and 4" would measure 12.566" so huge gap for to guess the correct measurement.

This comes in handy when your calipers or special shaft measuring device is 20 minutes away and down 3 stories.

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The logging diameter tape, also called a DBH tape (diameter at breast height) does the computation for you.

It is marked with the diameter measurements when wrapped around the tree.

Way too easy though

2. Re: Math needed for welding

Originally Posted by Blwaz23
If I wanted to learn the math for pipe fitting what would be a good source to read or what books would be the best to read?
2 pieces of good straight angle iron, 4 clamps and go after it.

3. WeldingWeb Apprentice
Join Date
Apr 2019
Location
USA
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Re: Math needed for welding

Problem solving. It is core to all problems. Find projects and work through the details, with an eye towards finding good techniques. This will help build core skills.

Work through a regular high school math curriculum, with a focus on word problems. They may seem lame, but they train thinking skills.

And learn to use a computer spreadsheet. They can be useful when working out something complex, like spiral stairs.

For example: If you lean a 15' ladder against a 12' wall, how far can the foot of the ladder be from the base of the wall?
Last edited by Rick42; 05-01-2019 at 10:20 PM.

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Re: Math needed for welding

SOHCAHTOA

was a word printed in large letters across the wall of our maths classroom. After the first couple of years I knew I'd never forget it

Sine X = O/H
Cosine X = A/H
Tanget X = O/A

SOHCAHTOA

Average spoonfed fabricators will rarely need trig, as drawings are so good these days, and tricky parts are often CNC cut these days.
Good fabricators will definitely use trig and geometry

5. Re: Math needed for welding

+1
Kahn academy is a good way to improve basic skills.
It will not give you practice in creative, career oriented, problem solving - but is a great skill builder.
i dont like kahn academy. just try maybe...
will help build your intuition.i used to watch some of it back in the day.... all u need is an ounce of intuition and u can figure out anything in the world, even make up your own formulas. Maybe a little more than an ounce, but you get the idea. That kahn guy drives me crazy, ooph..
And if your feeling over the top, try 3brown1blue or numberphille , but if you dont get it, downt worry, i really dont understand much of 3brown1blue, a little over my head sometimes, just watch it too help your visualization/intution/spatial skills https://www.youtube.com/channel/UCYO...17AJtAw/videos https://www.youtube.com/user/numberphile/videos

remeber, its all about visualizing stuff, then everything else will click and fall into place, rather than blindy trying too look at a bunch of videos on a bunch of different math topics, when they are all very similar. Also if its daunting, dont worry, youll get there with enough practice, i promise, just like welding, in a sense. We are all in the same boat I am trying to learn some of the strength of materials stuff/beams/columns/shear in the machinists handbook and it is crazy complicated. But most of the times, u can get by with a little guesswork and trial and error then pulling out a fancy formula, except the times when its worth its weight in gold.
Last edited by n00b; 05-19-2019 at 10:56 PM.

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Jan 2015
Location
Martha Lake, WA
Posts
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Re: Math needed for welding

The logging diameter tape, also called a DBH tape (diameter at breast height) does the computation for you.

It is marked with the diameter measurements when wrapped around the tree.

Way too easy though
When I was working as a Liaison Engineer (writing repairs for rejectable aircraft parts) I got a tag for an out of tolerance anti-icing duct. The duct was around 6" in diameter, very thin walled (probably around 10-15 thou) and flexible. The inspector reported the diameter with a number that went out to 4 decimal places. I got excited thinking of the exotic piece of measurement equipment that could hold this duct round and read the diameter accurate to within one ten thousands of an inch. When I asked the inspector to show me he whipped out his "pi tape" and said he wrapped it around the pipe and got a number. It ended in a fraction, which he put it in his calculator - 4 decimal places!
Last edited by jrporter; 05-20-2019 at 10:39 PM.

7. Re: Math needed for welding

Originally Posted by jrporter
When I was working as a Liaison Engineer (writing repairs for rejectable aircraft parts) I got a tag for an out of tolerance anti-icing duct. The duct was around 6" in diameter, very thin walled (probably around 10-15 thou) and flexible. The inspector reported the diameter with a number that went out to 4 decimal places. I got excited thinking of the exotic piece of measurement equipment that could hold this duct round and read the diameter accurate to within one ten thousands of an inch. When I asked the inspector to show me he whipped out his "pi tape" and said he wrapped it around the pipe and got a number. It ended in a fraction, which he put it in his calculator - 4 decimal places!
ooph. you guys are bringing me back to the horrors of sig fig math in chemistry last year.

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