My how time flies! Not a lot of shop time over the last few weeks, but I finally got some time today. And it was quite enjoyable!
Last time I’d just started bending the Tie Bars. I started with them because they were only 1/16” thick. The Arch Bars are 3/32” thick! That’s getting pretty substantial!
After I bent the middle bends, I used the hole jig to drill the two middle holes to attach the columns.
I wasn’t very happy with how this went. It worked, but it just felt squishy to me. I could wiggle the bar back and fortha bit and it just didn’t feel as precise as I would like.
Regardless, I finished up bending the four tie bars. This wasn’t a fast process. It took 15-20 minutes per bar to get things bent correctly so that it all lined up, wass just the right height, and didn’t have any twists in it anywhere. I just found it took a lot of tweaking.
For the next set of bars (Lower Arch Bars) I used a different technique. I calculated the location of the center holes and drilled them first.
Then I marked the locations where the bends should go.
The problem with drilling the holes first is that when you go to bend the bars, it wants to bend in the weakest spot – right where the hole is! :Duh: But, as long as I clamped over the hole and bent the other side it worked just fine. And I feel that the holes came out much more predictably.
Here’s one of the Lower Arch Bar fitted to the bending pattern. Again, quite the time consuming process.
And this picture shows the set of 12 bars with the column holes drilled and bent to shape.
To drill the outer holes (the ones for the journal boxes) I was going to go back to the drilling jig. But before I did that, I needed to re-make the hole guide. Turns out that my first attempt had a couple of problems. First, the cross bar was too flimsy (I used 1/16” sheet material). And second, the holes weren’t centered. They were in the correct positions lengthwise, just not centered. So, I made a new one using some 1/8” 1018 steel. This one turned out much better. The bottom one is the original one (note the non-centered holes), and the top one is the new one (with the more centered hole pattern).
And here’s how I drilled the holes for the journal boxes. Attach one of the bars to the jig, like so:
Flipping it over, you can see the template with the hole pattern.
Then I just drilled the holes! The little brass bar clamp is just to keep the bars aligned with the jig.
And did the same thing with the Upper Arch Bar and the Tie Bar (they are the same, with the exception of the thickness of the bar).
And finally, we have all 12 bars bent and drilled!
By this time it was getting to be the end of my shop time but I just had to get one of the frames assembled:
You can’t imagine how happy this little piece here made me! I still have to cut the bars to the correct length, but that’ll be the next step.
Getting close to having the trucks complete!
Thanks for looking in,
Kim