gas_explanations

gas explanations  

Explanations of unclear material, typography corrections, drawing corrections, and elaboration on what may have been left out goes here.

Furnace frame linkage issues

When nearing completion of your furnace frame, you may find that the short leg of each offset link interferes with the short leg of the L-shaped lifting arm that carries the two rollers. You will not be able to raise the long lifting levers completely.

My solution was to re-drill the hole for the inner roller, moving it ¾" closer to the bend of the L. Moving the rollers apart will cause the lifting arm to rotate downward, allowing full movement of the mechanism.

As a result, you will also need to move the hole for the furnace's central mounting stud toward the bend of the L. Although I did a bunch of trig calculations to figure out where that would be, I didn't completely trust them, so I waited and actually measured the location with everything otherwise assembled. I found I needed to move the hole by 1¾", but my frame is scaled up slightly, due to a slightly larger furnace diameter. You should be sure of the hole's correct location in your own case.

Don't forget that the stud holes need to be 5⁄16" diameter. You can remove the excess length from the lifting arms if you wish, but I'd recommend making sure everything's working first.

Finally, you may find that you can't move the lifting levers up past vertical. I found that filing a rounded notch in the lifting lever pivot where the offset link meets it will do the trick. My notches are about ¼" deep, and I can now rotate the lifting levers about five degrees past vertical.

Aaron Endelman