Moving forward on the wheels for the tender.
I mounted one of the blanks into my 3” Taig 4 jaw chuck (I have an adaptor for this chuck that I’ve made for other projects and it works quite well). I indicated it using the outside radius to get it fairly centered in the chuck. Then I faced off one side, nice and clean.
Next step was to pan out a good chunk on the wheel. This needed a 15
o slope on each side of the scooped-out section. To get this, I ground a tool with a 30
o angle with a nice broad rounded tip.
Then went about panning the first wheel. It seemed to be going quite well and was looking really good, except I noticed things sounded funny toward the outside of the section. I soon discovered that the edge of the tool was interfering terribly with the outside radius of the cut-out section.
And of course I had one of those “Duh…” moments. All you experienced guys saw this coming from a mile away, I’m sure. But I had to discover it on my own apparently.
So, I modified the tool and created a lot more clearance on the left side of the tip. I needed to get about 1/8” deep with the tool, so I cut the clearance that far back (plus some safety margin).
With that modification, things worked MUCH better! And I think I can still pull this one out and NOT have to scrap this wheel (at least, not for this bonehead move. Maybe for the next one
).
With the sloping edge of the tool, it was kind challenging to get the correct width of the carved-out area. In addition to the sloping tool, it was difficult to get a good datum on the very center of the wheel. So, I did a ‘good eyeball’ estimate and carved out most of the area, leaving a nice buffer on each side. Once I got to the correct depth (1/8”) I snuck up on the inside and outside radius, measuring with the dial calipers till I got the correct inside (5/8”) and outside (1 3/4") diameters.
With that completed, next was to make the 5/16” axle hole. I started this with a center and then drilling a 1/4" hole all the way through.
Then, to ensure that the axle hole was perpendicular to the freshly machined side of the wheel, I bored the hole out to just under 5/16” ( went to about 0.304”, leaving about 8 thousandths for the reamer).
Having ensured the hole was perpendicular, I then reamed it out with a 5/16” reamer:
Having completed all operations on the first side, I flipped the wheel around in the 4 jaw and then centered it using the freshly cut axle hole.
Next op was to face off this side and cut it down to the correct width for the wheel (7/16”).
And repeat the panning operation on this side (as described above).
And that is the first series of operation for each wheel blank. After I get all 8 wheels to this stage, then I’ll work on turning the flange and the tread.
I got two wheels turned up to this point. I think I’m getting faster. First one took 4-5 hours because I had to grind the panning tool (and then re-grind it to fix the relief problem) and figure out how to do all the steps. But the second one only took 90 min or so (I didn’t actually time it, but it was much faster). I’m thinking they’ll get even faster, but it will still take some time. I’ve got 6 more of them to go!
Anyway, here’s my progress so far, showing the two completed up to this point and one of the ‘blanks’ just for fun.
Thanks for taking a look!
Kim