Well thanks once again for following along the rebuild of this chuck wagon undercarriage.
For those of you that have been following along, you found out that the undercarriage has hounds.
And other projects that we have done also,
you're well aware of that there are tongues in undercarriages.
Well this week we're going to talk about a different little critter.
That is a spider in a farm wagon undercarriage.
Well several weeks ago we built the hubs for this chuck wagon undercarriage that we're rebuilding.
Next we need to start assembling the spokes and the felloes.
Now you're probably well aware of by now that spokes are not turned round, but they have kind of
an egg shape pattern to them. Round on the bottom side, just like an egg, with a little more of a
point on the leading edge, which as I build these on a wheel stand, that point, or leading edge,
is facing up. When they're on the undercarriage that point will be facing out.
Well a common hub spoke,
like these that I'm working on,
generally have more taper to them than a Sarven style spoke does.
Now when these are chucked up into the copy lathe, or the pattern lathe,
oftentimes these are chucked up center to center between the headstock and the tail stock.
Well to achieve this taper,
when it's done in this manner,
that taper is cut into both sides of that spoke
as you can see here in the pattern that I've drawn out.
Well the problem with that is if that spoke was just driven
into the hub as it was manufactured,
the tip of that spoke would actually be facing down,
where it should be facing parallel or up,
again as I'm building them on the stand or as the wheel would be facing out.
This is what creates the dish in the wheel which gives stability for the side thrust.
Now if the operator were to take enough time and move that center point up on one end of that spoke
we could actually have all the taper to the back side of the spoke as it should be,
but oftentimes these have a double taper to them,
and that is the case with the spokes that I have to work here.
Now generally spokes are made just a little oversized. These are two inch spokes, but they're
actually measure out at two and an eighth, so i have a little room that I can adjust these.
So as I put these up against the face of the sander, I can take that leading edge and make
it a flat straight edge, so as it comes out of the hub
it will be a straight, perpendicular line out.
Now you might think that doesn't create any dish, but because of the style of the spoke,
there still is, in the body of the spoke, 3/8 of an inch dish,
and when I set the tires and do all my adjustments
I'll actually increase that also.
So on my drawing I drew a straight line right through
the shoulder of where the tenon would be and you can see where the top spoke
on my drawing would
come out straight from the hub,
whereas the bottom one would actually have a declining taper to it,
which would give it a negative dish.
And that's what I need to fix on these spokes I'm working on.
Now the back side of the tenon also matches a taper in the back side of the mortise in the hub.
Now I've gotten numbers of videos in building heavy wheels that explains
all that, so I won't duplicate that now, but I need to match that and fit each
of these spokes individually into the mortises that I've cut into these hubs.
So this process of adjusting the spoke tenons, as they fit into the mortises in the hub,
whether it be a buggy hub or a wagon hub like these,
is what is called the process of building the spider.
This is the foundation to building the dish the correct dish into the wheels.
There are some shops that will offer wheels in this spider form
and then each individual shop can
adjust them to diameter as they need them for their own needs.
From here on out we'll go ahead and finish building these wheels.
Well I have the axles, front and back both, propped up on saw horses that are both the same height.
So I'm going to measure from the floor up and see what the height of the bolsters are.
In this case I have five inches difference between the front axle bolster and the rear axle bolster.
That five inches difference needs to equate into ten inches different in wheel diameters.
So these wheels I'm going to make 42 in the front and 52 in the rear.
Well this building of the spider is foundational to the correct dish in the wheel.
Now that we have the felloes on, you've seen me set tires number of times. but that's the last
step in buildings wheels.
I'll size and set the tires and have these finished up
ready to go on this chuckwagon undercarriage.
Once again, thanks for watching!