Best Glue for LP cover seams?

Try carpenter's glue. You can get it at any hardware store.

Make sure the two surfaces you're gluing are clean & have as little oil from hands as possible. A couple firm strokes with with a paper towel should do it or try a swipe with fine grit sandpaper for tough to clean areas. Press it with between something like two heavy hardback books. Don't put so much glue on you glue your album cover to a book.

use a good quality glue stick

UHU Office Glue Pen manufactured in Germany. Ideal for paper & cardboard. This pen can be purchased in the archival/scrapbook supplies ($6.00) @ JoAnne's along with Scotch acid-free clear tape($5.00).

I use Elmer's Glue. A thin bead of glue and a heavy old book placed on the seam for an hour holds the bond.

I second the glue stick. I have to buy a pack every year for my children as part of their school supplies. I've been using one for years and it works well 95% of the time (a few times needed a second application).

Glue sticks always worked for me, too.

I've always had the best luck with Sobo Glue. It seems to be a little more flexible then elmers or glue sticks. I get it at art supply or crafts supply stores.

Any contact adhesive is fine - Uhu, Evostick anything like that. A layer on each surface, leave to part dry and then put together. Works every time and doesn't require any need to clamp up the cover.

Charlie

I use double sided transparent tape, works great

Why does LP cover restoration have to be so difficult ? The actual answer is to simply use the glue (of your choice) and glue the cardboard parts together.

If regluing was done to your satisfaction,than it is of no consequence. However, if we are considering re-selling than the discussion changes.

I use archival products; curator approved tape and glue. Of course, I own a collection that many would die for(stereophile "tang"). But that's me. For the person who just wants to glue the cardboard together, Hey go for it. There is no financial consequence unless you intend to sell what you own. LP grading systems downgrade certian fixes. In fact, it probably best on certian select items to leave them "as is" and take your chances on the secondary market. Besides, no auction house that I know of does business with 99% of what's in consumer hands. Remember,just one scratch can reduce the value of a recording by 99%. So, "do what you will", keeping in mind the resale consequences. All the best.