I’ve been using art shop latex for years, it works well. £12 a litre locally. you need to roll off the dried stuff from the tyre / rim bead area when refitting tyres, but this 5 min job is worth the way it seals thorn holes even when it seems to be dry inside the tyre. it does mean no spillage and mess on the trail when you put a tube in, only needed to do this once so far in many miles of woods / towpath riding and had 2 flats in about 3 years now.
adding 20% or so water to it helps keep it liquid for longer, there’s probably a solvent you can add that turns it into the same stuff as stans but i’ve never felt the need to experiment as what i have works fine. i use it to seal tubeless tyres onto std (X430, 717 etc) rims that have plumbers tape wrapped over the spoke holes, my SS lasted from October till now, without more than a fortnighly air top-up, until i flinted the rear RQ ust this week. replaced it with a clean race king UST tyre to the back in 10 mins with just over half an aerosol can cap of latex / water mix. pour a bit between bead and rim each side and let it run round before inflating with a track pump, goes up every time once you get the knack. if you use UST rims and tyres just a 30-70 water-latex mix in as sealant is all you need and it’s been faultless on my shimano and dt UST wheels with maxxis and conti tyres. stans have been a bit more hit/miss but still good overall.
it’s a minor faff at times, but i prefer predictable faff in the garage to faff on the trails that i get at least every other ride with inner tubes.
hope that’s of use..
