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Old 7th April 2011, 07:37 PM
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Bonzo Bonzo is offline
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Join Date: Jul 2007
Location: Cornwall
Posts: 3,321
Smile Testing your welds part 2

Here we go for part 2 of this post.

Here is a picture of welds A, B & C after the weld cap has been removed ( Fettled flat )

On close visual inspection of all 3 welds, from the outside face of each joint there is nothing visualy to distinguish any one from another.
No porosity evident, no inclusions evident.

Without polishing & etching, all welds appear to look as they should do when making a simple visual inspection of a weld.

Now here is a picture of wels A, B & C after they have been subjected to a very mild bend test of about 100 - 120 degrees
A true test would be made by bending the sample through a full 180 degrees, with a radius appropiate to the thickness of the material being tested !!

It is self evident that sample A has failed the bend test miserably & is a totally unsuitable weld joint for the Roadster

As there was really nothing to choose from between the next 2 samples, I chose to test the strength of the root weld sample B ( Could be argued that it looked the weaker of the 2 remaining samples )

Tested sample B buy bending pressing the dressed face to put maximum stress on the welds root.
The root held firm & I am confident that it would bend to 180 degrees without showing any signs of stress fractures.

Sample B was tested in the other direction to test the front face of the weld.
Nothing undue was observed.

In sumary, if you are unsure of your welds, keep practicing & don't be afraid to test your welds frequently .... It won't take long & will give you peace of mind, knowing that you will be building a safe, sturdy chassis

I hope this helps some of the novice welders on the forum.
I am not a complete idiot...........Some of the parts are missing !!
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