Building a 4x wheel

[Mick F]

It just so happens, that I'm rebuilding a rear wheel with a new hub.
The flanges are a tad taller than the old one and slightly differently spaced, and I have a sneaking suspicion that I could run out of thread on the spokes before it's nice and tight.

It's 3x 36h just like it was before and the spokes are now on their third rebuild.

If I was to lace it 4x, the spokes may fit better?
I don't think I've ever seen a 4x wheel, so are there any tips that anyone has for me? I can build 3x with my eyes closed!
Can I even build 4x in 36h?

I may not have to do this, but it's possible I could have problems with the present re-build.
Yes, I know I could buy new (shorter) spokes.
I fancy a challenge.

[fastpedaller]

With 4x you'll need much longer spokes! The height of the flange won't make a lot of difference - If you put some figures into spocalc or similar you'll see what the difference is.If you visualise it by looking at the tangent the spoke is making with the hub, and then 'rotate' a little you'll see very little length change, mostly angle. You'll probably find for 10mm change on the radius of the flange, it's only 2mm length change on the spoke.

[Mick F]

Yes, that's my point.
My spokes are possibly a tad too long for 3x.

Rather than buy new spokes, they may be long enough to do 4x.
This will give me a wheel without the need to buy new spokes, and it'll also give me a challenge.

[fastpedaller]

My previous note's now edited

[tatanab]

4 cross was common in the days of 40 hole 27" wheels. I have built 36 hole 4 cross when that is the length of spoke I happen to have in the shed, no problems. Use your spoke length calculator to check that your existing spokes will be long enough, or you could just wing it and if they are then you are in luck, if they are not the worst is that you have to strip the wheel. All good experience.

[Mick F]

Dunno what the rim ERD is.

I was using Rigida Chrina rims ERD 603 and a bit.
I was using a Campag Chorus rear hub, but now fitted a Miche Racing Box.

Latterly, I changed rims to Ambrosio Excellence and they appeared similar to the Chrina, so I "winged it" and used the same spokes.
All was well, but I suspect that the Ambrosio is less ERD than the Chrina.

My spokes are:
(I still have the info)
18 Sapim Strong 292mm Drive Side
18 Sapim Race 294mm Non-drive Side

The wheel with the the new Miche hub with the original spokes and the Ambrosio Excellence rim seems to be ok. One or two of the DS spokes are creaking as I turned the last adjustment ......... and that tells me that they are at the end of their threads. If I look at all the nipple tops in the well of the rim, all the ends of the spokes are proud.

The hubs ................
I measured the Campag one myself and am confident the measurements are correct.
CAMPAG:
NDS Flange: 44
NDS Flange to Centre: 37
DS Flange: 46
DS Flange to Centre: 17

From what I can glean from the internet, the Miche hub is:
NDS Flange: 47 46
NDS Flange to Centre: 39 37
DS Flange: 47 46
DS Flange to Centre: 16 15
The two numbers are two different websites!
Maybe take the mean of the two?
I never bothered measuring the hub because I thought I'd wing it again. I had nothing to lose.

Any comments regarding the length of spoke 3x versus 4x?

[Mick F]

PS:
Just checked a couple of online spoke calcs using figures I know.
Looks like the spokes need to be 7mm longer.

Therefore it looks like I'm out of luck because 7mm is too far. The spokes would reach, but there'd be lots of threads showing and I don't like that.

I'll stick with what I've got and my fingers are crossed (sorry about the pun) that I don't need to tighten up further.

[Brucey]

Mick, if you fit spoke washers at the hub end then this will 'consume' up to about 0.5mm of spoke length. It certainly won't do much harm anyway.

Your change in flange diameter will cause the spokes to appear to be ~0.7mm longer than they were before, on a 36x3 build.

cheers

[deliquium]

Dunno what the rim ERD is.

I never trust manufacturers' ERD figures This technique, courtesy of Roger Musson is simple if one has 2 spare or gash spokes to keep in the wheelbuilding parts drawer. Preferably super glue the nipples on so they don't move

Click on image for larger version

[Mick F]

Mick, if you fit spoke washers at the hub end then this will 'consume' up to about 0.5mm of spoke length. It certainly won't do much harm anyway.

Thanks for the advice. I have a pack of washers left over from a wheelbuild from ages ago.

What I need really, are washers that'll fit under the nipple-heads to increase the apparent ERD ............ if you see what I mean.

Dunno what the rim ERD is.

I never trust manufacturers' ERD figures This technique, courtesy of Roger Musson is simple if one has 2 spare or gash spokes to keep in the wheelbuilding parts drawer. Preferably super glue the nipples on so they don't move

Yep.
That is exactly what I do.

If this wheel isn't good enough ........ though it feels absolutely fine and strong .................... I'll have to go back to square one and measure up and buy new spokes.
If I can "adjust" the wheel with washers etc, all can be done one spoke at a time instead of a complete re-build ........ which is my preferred option.

It'll be a while yet before the Mercian is back on the road as it's still in bits. BB serviced, new rear hub, front hub serviced, headset serviced, cassette cleaned. Still to do brakes, cables, pedals, chain, front mech, rear mech. Then it's reassembly time!

Only then will I be able to test ride the rear wheel.

[meic]

Dunno what the rim ERD is.

I never trust manufacturers' ERD figures This technique, courtesy of Roger Musson is simple if one has 2 spare or gash spokes to keep in the wheelbuilding parts drawer. Preferably super glue the nipples on so they don't move

Click on image for larger version

But have you found any of the manufacturers' ERD's to be wrong? If so by how much?
Not counting the unfathomably unusual Mavic's ERDs.

[deliquium]

Dunno what the rim ERD is.

I never trust manufacturers' ERD figures This technique, courtesy of Roger Musson is simple if one has 2 spare or gash spokes to keep in the wheelbuilding parts drawer. Preferably super glue the nipples on so they don't move

Click on image for larger version

But have you found any of the manufacturers' ERD's to be wrong? If so by how much?
Not counting the unfathomably unusual Mavic's ERDs.

Yes, but I can't recall now whether it was Rigida or Halo and then there's the suppliers who sometimes quote incorrect or out of date ERDs

Not a fan of Mavic rims anymore

[Mick F]

I had a series of Rigida Chrina rims.
Every single one of them had different ERDs. I've had seven of them in total.
At one time, the front tyre would fit on easily, but the rear one was terrible! Even swapping the tyres over didn't help. It wasn't the tyre, it was the rim.
Ferrit Worrier is on record on here of chucking his out because he couldn't get a tyre on.

Since building my own wheels, I've always measured the ERD for myself, but they have mainly been Chrina rims. I've done a small front wheel for the Chopper, and two 27" wheels for Barbarella our utility bike.

The latest rims - Ambrosio Excellence - I never bothered measuring and took a punt that the spokes from the Chrinas would fit, and they did.

[meic]

No numbers though, was it enough to change the required spoke length?

[Des49]

Sorry for the slight thread deviation, but how are you getting on with your Ambrosio Excellence rims MickF?

My latest set of Mavic Open Pro rims have me already worried and checking wear carefully on the rear, about a year since I replaced the rim.