As soon as I clean up the inside of the rear rim I'll be calling them prior to shipping the rims for straightening. I'll mention that there are customers for at least two sets of smaller-head spokes.
Wheel Building
- Thread starter Cyborg
- Start date
Good point if forgot to mention that. When you get a set of spokes from Central Wheel you just get 40 identical spokes. From Devon rims you get 20 spokes marked for inside and 20 for outside and the head angles are slightly different so they fit the spoke flange correctly and allow the spoke to line up with the rim holes.
To add my two cents worth. I have what I believe are original spokes from a Vaughan Green stash and these are swaged spokes.
I have built a set recently from Devon rim company and I have also built a set from Buchanan’s. Both lots had larger than original heads and needed a tickle on one side to get them to clear each other.
I agreed with others that four cross is the right way to go and remember that they should pull against each other. I build mine with drums on. As per Glen and Robert down to about 10 thou run out or better in all directions. 55-70 inch pounds on torque. I know Buchanan’s spec higher, but boy things seem tight when you try to get that tight.
With a recently set of hubs the new flange where spoke plate mounts was not machined true and was running out by more than five thou each side which caused a bit of an inconvenience. I had to re machine them.
Happy new year Ken. Hope to have a visit this year.
I have built a set recently from Devon rim company and I have also built a set from Buchanan’s. Both lots had larger than original heads and needed a tickle on one side to get them to clear each other.
I agreed with others that four cross is the right way to go and remember that they should pull against each other. I build mine with drums on. As per Glen and Robert down to about 10 thou run out or better in all directions. 55-70 inch pounds on torque. I know Buchanan’s spec higher, but boy things seem tight when you try to get that tight.
With a recently set of hubs the new flange where spoke plate mounts was not machined true and was running out by more than five thou each side which caused a bit of an inconvenience. I had to re machine them.
Happy new year Ken. Hope to have a visit this year.
The first photograph is a spoke from my Vincent next to one I bought from Ron Kemp in the 1990s, showing the latter is bent at 90° but the former at 22.5° less than 90° (i.e. 67.5°).
The Vincent spoke is one from the inside of the spoke flange whose head faces the drum. The second photograph shows the flange, with the camera aligned with the edge of one of the drums to make it clear the spoke flange isn't flat, but rather is bent inwards by some as-yet-to-be-determined angle.
Since the spokes in question seat against the outer surfaces of the flange, the relevant distance is shown in the above to be 3.34". The length of the spokes where they enter the rim is 8½" so the angle the spokes make is sin–1(1.67"/8.5")= 11.3°.
For maximum strength the entire circumference of a spoke head should make contact with the spoke flange, which wouldn't be the case for the Vincent spoke shown in the first photograph unless it turns out the angle at which the flange is bent inwards is 11°. No matter what, the 90° bend of the Ron Kemp spoke, plus the "missing metal" from part of the slot (shown in green), means relatively little of the metal from the spoke would make contact.
Unless the angle(s) of the spokes matches that of the flange, there will be remarkably little metal in contact. If the angle of the flange does turn out to be, say, 11° it means the 20 spokes whose heads point inwards (i.e. the ones that are presently trapped in my hub) should be bent by 11° more than 90°, i.e 101°, to make full contact.
Anyway, there are two issues the ideal set of spokes would solve. The diameter of their heads would be small enough to slip between the flange and drum, and they would come bent with different angles for ones whose head face in and that face out.
It will be easier and more accurate to make a measurement once the flanges are removed, but the following is good enough for now.
Unfortunately, now it gets complicated. Within experimental uncertainty, the 12.5° I measured with a ruler held against the flange is consistent with the 11.3° I calculated for the angle of the spokes in the previous post (10.4° for the inner-facing spokes because of the thickness of the flanges). This would mean the spokes would need a 90° bend on the end if each of them went straight from the flange to the nearest point on the rim. But, they don't. They skim along the surface of the flange almost tangential to it so the angle has to be greater.[*] But, by how much greater isn't by any means straightforward to calculate.
[*]Instead of a spoke aimed for the nearest point on the rim, which would require a 90° angle for the head, if it were aimed 180° away from that it would be well outside the rim so it would require an acute angle less than 90° for the head. The actual situation is somewhere between these extremes.
For what it's worth, as the next photograph shows, to within the accuracy I can determine it in situ,Vincent used the same angles for both inner and outer spokes.
Unfortunately, now it gets complicated. Within experimental uncertainty, the 12.5° I measured with a ruler held against the flange is consistent with the 11.3° I calculated for the angle of the spokes in the previous post (10.4° for the inner-facing spokes because of the thickness of the flanges). This would mean the spokes would need a 90° bend on the end if each of them went straight from the flange to the nearest point on the rim. But, they don't. They skim along the surface of the flange almost tangential to it so the angle has to be greater.[*] But, by how much greater isn't by any means straightforward to calculate.
[*]Instead of a spoke aimed for the nearest point on the rim, which would require a 90° angle for the head, if it were aimed 180° away from that it would be well outside the rim so it would require an acute angle less than 90° for the head. The actual situation is somewhere between these extremes.
For what it's worth, as the next photograph shows, to within the accuracy I can determine it in situ,Vincent used the same angles for both inner and outer spokes.
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MM,
Have you spoken with the folks at Buchanan's? Recently I rebuilt a set of Triumph pre conical wheels. I ordered the spoke set from one of the usual suppliers of Triumph parts. When the spokes arrived they were bundled in sets and marked only by set number. As I'm sure you know the pre conical Triumph rear hub has flanges. Knowing that the spokes sets were from Buchanan's I called and asked which set was inside the flange and which went outside as I was having a hard time discerning this. Having only built Guzzi wheels before, which are all 'Nail Heads" and straight I didn't know which set went where. The lady on the other end of the phone told me which was which. She then commented that she was surprised that she didn't field more calls asking which spokes went inside or outside of flanges. So Buchanan's is aware this angle is important and I know several section members have successfully built wheels for Vincents with their products. Perhaps they can be of some help.
Steven
Have you spoken with the folks at Buchanan's? Recently I rebuilt a set of Triumph pre conical wheels. I ordered the spoke set from one of the usual suppliers of Triumph parts. When the spokes arrived they were bundled in sets and marked only by set number. As I'm sure you know the pre conical Triumph rear hub has flanges. Knowing that the spokes sets were from Buchanan's I called and asked which set was inside the flange and which went outside as I was having a hard time discerning this. Having only built Guzzi wheels before, which are all 'Nail Heads" and straight I didn't know which set went where. The lady on the other end of the phone told me which was which. She then commented that she was surprised that she didn't field more calls asking which spokes went inside or outside of flanges. So Buchanan's is aware this angle is important and I know several section members have successfully built wheels for Vincents with their products. Perhaps they can be of some help.
Steven
No, I haven't spoken with them yet, mainly because I'm already deep down a rabbit hole trying to determine the optimum design for spoked wheels. The following schematic indicates the issue du jour I've been wasting time thinking about.
It seems reasonable that the "best" (strongest) design would have the inside of the head in full contact with the spoke flange when the nut at the other end has the proper torque on it. If this is the case, the diagram above shows that if the head starts out life at >90° with respect to the face of the flange, as do my Vincent spokes, achieving that full contact would be impossible.
But, maybe it just seems reasonable, but isn't. Maybe the torque is small enough that it's incapable of bending the end more than a tiny amount, in which case the head should start (and end) its life at exactly 90° with respect to the flange. Or maybe spokes "never" break near the head, so the angle doesn't matter. Unfortunately, the science of spoke design dates to before Guttenberg since I haven't found any technical books on the subject as yet.