Removing Stress

Now that I have some idea of what you are trying to accomplish I would bolt that together, 100 MM is less then 4" per side, why would you weld and distort something that small?
You could mill that from a solid piece of cast iron in less time then making the individual parts, welding, stress relieving and finish machining of the weldment.
 
Wreck, I believe the point is to make a milling fixture for the lathe. That is, he does not yet have the capability to mill it from solid.

Although bolting it together is a good option.

-brino
 
Sorry Wreck Wreck but unfortunately I have to disagree, I have no mill, no cast iron blocks and cannot afford them.:apologize:
This is the easiest way I can get any form of milling done.
The first version was a good learning project and now I can make a better more rigid one.
I would love a mill and all the resulting tools but its just a pipe dream.
 
savarin,

In a weldment that small, I highly doubt you will have to worry about distortion when you machine it, from experience. You are using mild hot rolled steel plate, which is very soft, I assume. The welding is going to generate enough heat to eliminate and stresses induced from welding. I say weld it up and get after it. I also suggest to machine the surfaces to near size, then come back and finish the flat surfaces to get them square to each other.

Ken
 
I don't think you will have to stress relieve a welded part that small, but I would bolt it together.
 
4gsr said:
savarin,

In a weldment that small, I highly doubt you will have to worry about distortion when you machine it, from experience. You are using mild hot rolled steel plate, which is very soft, I assume. The welding is going to generate enough heat to eliminate and stresses induced from welding. I say weld it up and get after it. I also suggest to machine the surfaces to near size, then come back and finish the flat surfaces to get them square to each other.

Ken
Click to expand...
Thats what I was hoping to hear.
 
A lot to do with stress relief of weldments temperature at which the weldment is done, and the amount of material removed after cooling. Most distortion comes from the fact that the weld shrinks so much as it cools, and "pulls" surrounding metal mass inward towards the center of the weld. And of course metal (most) expands when heated, so if the entire thing is hot to begin with, everything shrinks in all directions and this lessens the localized effect of the weld area shrinkage.

The other thing is how much material you remove after welding. And of course where in relation to the stress direction created by the cooled weld. Sometimes it is better not to try and clamp everything tightly in a finished position, like trying to hold this angle plate square, because you know that as you weld it, the heat/cool will try to make things move. If you go ahead and let them move, but in the direction you want them to to bring them into a desired position, less post weld stress will be there to begin with. But that's part of the black magic of welding up stuff without much distortion. Lots of educated, predetermined positioning and weld sequence.

A weldment that small shouldn't really present that much of a challenge in all of this, but you can learn a lot about the effects of different approaches to creating proper weldments.

Make sparks!
 
Tony Wells said:
A weldment that small shouldn't really present that much of a challenge in all of this, but you can learn a lot about the effects of different approaches to creating proper weldments.
Click to expand...

....and @savarin, please share what you do and see so we can all learn.
I can see needing to build up some parts of similar size and I could use any hints you produce.
Thanks!
-brino
 
no worries Brino, I'm collecting the pics as I go.
I'm also wondering if I can also design in a tilt function although I cant see a need yet.
 
Before I got a mill, I had to do my milling on my lathe. I got an 8" square Blanchard ground steel plate 3/4" thick off eBay pretty cheap. I made a plug to go in it and mount to my cross slide after removing the compound. I drilled a matrix of 3/8-16 tapped holes in the plate. It mounts in just a couple minutes and gives me a nice flat table that I could feed in both directions ( I have cross slide feed on my lathe). I know the height from the table to spindle centerline and shim a part to the right heir an mill. I can mount a vise on the plate or an angle plate and then put the vise on the angle plate. It works great and is pretty versatile. I still use it once in a while. Just a thought.
 
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