I have a new wheel. I threaded it myself.

I messed up a bit on the pattern so that the hole for the air is jammed into a small spoke triangle.

I am thinking about undoing the entire thing. Do I have to replace the spokes?

No, the spokes should be fine. Lace 'r up again!

the only problem, and it may be enough to cause most to re-lace the wheel, is that it may be difficult or possibly even impossible to fill the tire, depending on your pump-head and valve length. i've done the same thing, probably on more than one occasion , and just left it that way for a while. eventually when i had good reason to rebuild the wheel, i fixed it.

I just did the same thing on my first wheel build. I'm going to relace the wheel again and make sure I am careful when bending the spokes and I take my time getting even tension across the entire wheel.

No, you don't have to replace the spokes but you do have to relace the wheel. You may not have to remove all the spokes and start again but it can be difficult to find where you have made a mistake.

IF The pattern is OK, is everything is right except for the placement of the valve hole, then it's very fast and easy to relace, without taking the spokes from the hub.

Get some string, or dental floss, and tie each pair of spokes together at the cross. Then keeping the wheel flat on your table, remove all the nipples. Move the rim around 2 spoke holes, so the valve is in the right place, and the right/left or (top/bottom with the wheel flat) spokes are going to the right holes in the rim. Then connect the nipples working the crossed pairs together.

If you've finished, tensioned and trued the wheel, the easier option is to drill a new valve hole in the right place, but I know that nobody here on BF would be able to live with a wheel that had two valve holes. Perish the thought and forget that I dared suggest it.

BTW- you really don't have to do anything at all. Having the valve hole at a cross will not affect anything, and you won't have issues pumping (test for yourself). BITD it wasn't rare to see newbies with the spokes crossing at the valve hole. Back then we used to karate chop our Silca pumps to remove them, and the worst that would happen is they'd bang into the cross "safety net" and bounce back a bit.

The ONLY drawback to having the spokes cross at the valve is that snooty riders will point it out.

Sheldon Brown's wheel building instructions pretty much prevent this problem.

It shouldn't be too hard to do. If it is a shift of one spoke or so, you could probably loosen all the spokes, then remove one spoke, then move all the rest forward one hole. You still need to re-true the whole wheel.

Are you worried about looks, or is the build significantly impacting functionality?

It's OK to do this by two spokes but not by one. The spoke holes in the rim are offset left and right. Crossing them makes for a bad wheel.

IME, i found this to be more difficult than i had imagined. i fell foul of the fact that the spokes being moved needed extra length depending on the direction i was moving them, mostly because the hub was still connected to the rest of the spokes. loosening may be, as mentioned, be all that's needed, but eventually i had to remove them all and start over. OP, YMMV though.

IMO, anyone that has attempted to do what the OP suggests will soon find it next to impossible and will in short order de-lace and start all over.

Good Point.

I think Small/Small is 2 spokes off from big/big, so one should be ok.
However, if you're relacing one of the other patterns, then it would involve flipping the rim unless it is an OC rim.

And, that may be stretching the length of the spokes a little bit.

Flipping the rim doesn't change the left-right pattern.

Say one "Right" spoke is fixed.
Then you flip the rim, then it would now be in a "Left" hole.

So, you could rotate a single spoke.

Agreed. The rear wheel of our tandem is a 48-spoke lacing that I did about 38 years ago making the same mistake as the OP. It's marginally harder to put the pump head onto the valve stem but not really a problem and the wheel has been working fine so I see no reason to redo it until some component wears out and I need to rebuild the wheel.

You are mistaken. A right spoke is in a right hole in the rim. Flip the rim around. Now the right spoke is in a left hole. This is a bad situation. The spoke reaches from the right flange to the hole on the left side of the rim.

+1

You cannot reverse either the rim or hub right for left because then the spoke will be going from one side in the hub to the opposite in the rim. We recently had a thread where someone was having spoke breakage at the threads because of this very issue.

OTOH - it's easy to accidentally reverse the wind of the hub, so counter clockwise spokes are now clockwise. This happens to people when attaching the second phase of spokes on the 1st flange. I suspect it's this very error which led to the problem this thread is about.

I lace up a wheel a bit differently than many. I'll put my first left and right pulling spokes through the hub and into the first two corresponding holes behind the valve hole. You have to start a couple hub holes above the label if you want the label to line up with the valve stem on the finished wheel (OCD). This assures that the spokes on the other side of the valve hole will be trailing spokes thus putting the valve hole in the generally accepted appropriate placement. I lace all of my pulling spokes in pairs first, skipping the holes where the trailing spokes will go. Then I lace the first set of trailing spokes checking for appropriate rotation of the hub, label and valve hole placement, and cross pattern. From that point the lacing is fool proof as long as you maintain the appropriate cross pattern. Using this technique I can lace a 36 spoke wheel 3 or 4 cross in about 20-25 minutes working at a leisurely pace, rockin out to my favorite tunes and enjoying my beverage of choice. There might be faster ways, but I do this for fun in my spare time, not on a production line. Since I started doing it this way, I've never had to back up to figure out and correct a mistake in lacing.

I've probably built a half dozen wheels so far, so I'm nowhere near "experienced," but my habit is to simply keep a correctly built wheel nearby for comparison while lacing a new wheel.

Sometimes, but not nearly always. It is important to check for this just in case, but it is very common for rim holes to be drilled straight down the middle. Certainly my favorite Kinlin rims are.

Unless your (my new rims) rims are designed exactly for that, intended to be cross laced.

Of course, I wish I would have known that before I laced them the traditional (wrong) way. I had to redo both wheels.

I would do a laceover. Buy another rim and lay it over the laced wheel with the orientation and phase of the spokes the way they should be. Then secure the 2 rims together with tape at 3 equidistant points. Transfer the spokes one at a time from the badly built wheel to the new rim until you have filled the new rim with a couple of turns on each nipple to secure. Then true the wheel. Granted, you'll have an extra rim, but it could be done again if you ever trash a wheel on the road.

That's just foolish unless the OP WANTS an extra rim laying around for next to eternity.
IF they can lace it wrong, they can lace it correctly and have a usable wheel DAYS before the spare rim shows up.

Or if you have a trash rim or can borrow one from an LBS with the same number of holes as your new wheel, you can make the exchange twice. Once onto the trash rim, and then back onto your new rim. Return the borrowed trash rim, and you are good to go. Sounds like double work, but there will be no chance of a screw up if you make the first exchange correctly by rotating the trash rim to the right position against the new rim. And of course you don't have to true and tension the trash intermediate wheel. It is just a place holder.

Right, but see my modification of his idea.