Trouble lining up

I don't have this with everything I've built, but this is really annoying. I'll have several items (such as for a floor or ceiling) that are the EXACT width, and at the exact location (maybe also overlapping, at least touching), but they'll sometimes show a few pixel difference in height.

It's really annoying. by adjusting the height of each block individually I can usually get things to mostly even out, but it will still look like a seam. I can also change the seams' color/texture to help this, but that depends on the structure. Then, I still don't know what will happen when I rez the building elsewhere, such as on a buyer's land. Will the objects stay connected and be smooth, or will they take the new measurements and go out of wack?

Is there a fix/ way around this/etc? It's maddening taking 2 blocks exactly .5m thick, putting them both at a height of 159.70, and seeing them not line up. Move one up to 159.72 and it still isn't perfect but it's alot closer. It's driving me insane!

Unfortunately there is no fix for this. Personally I zoom in and check every connecting edge individually and get them aligned as well as the game will allow, but I only seem to get that perfect fit about 50 – 60 % of the time. I have experienced this for most of this year although prior to that it wasn’t a problem so presumably Linden can fix it if they got off of their arses. You can also use texturing to help get rid of seams although I have been forced to not use a preferred textured because it just didn’t look right with the slight un-alignment. Although I am a perfectionist when it comes to building and this issue really bugs me, I have sold thousands of prefabs over the last few years and no one has ever complained about the quality of building. You need to remember that the majority of people viewing your items are going to be doing so in mouse view or using a standard camera distance so won’t see any un-alignment. In the event that people do zoom in close to admire your handy work chances are they are aware of the limitation of the building tools and realise that objects are designed to be viewed from a distance. Just try and do your best without getting hung up on those slight un-alignments, although that’s easier said than done!

I'm getting better results with a tool called prim docker. It aligns prims better than I can do numerically and I find I can relax and accept how it turns out. The seams still show sometimes, but aligning prims is so much faster and easier that it keeps the frustration to a minimum and makes building a more pleasant experience.

I build to a grid of 0.125 metres, except when doing detail work. Stuff generally behaves itself this way, though occasionally I see things like Z 50.503 that needs some fixing. For the most part it works out fine, though sticking to set thicknesses (any multiples of 0.25m mostly) helps.

For detail work it's trickier.

I also just started using Prim Docker and I find that it makes building so much faster. I do understand the frustration over prims not aligning perfectly and seems showing despite apparent perfect alignment. One trick a friend taught me is to texture the touching edges with a completely transparent (alpha channel) texture. Obviously, it won't work in every case, but maybe it will help a little.