I want to antique chalk paint my dining table

I don't think chalk paint requires presanding the whole piece.

I would try using a mild stripper such as Citristrip which is non caustic and easy to use. After scraping and thoroughly wiping clean, you should be able to paint with chalk paint to a smooth finish.

With my experience using chalk paint NO prep is needed. IF the table does have a high gloss finish you may want to use a fine sand paper to at least break up the finish.Clean it well of the dust and then apply chalk paint .Good Luck! I love using chalk paint! Just not sure how easy it would be strip off ? lol

You just need to lightly sand it to give the paint something to stick to

I have found chalk paint will adhere to the varnished surfaces I've used it on. Just make sure the table is clean and grease free before beginning.

Here's a great article for beginners!

https://www.thinkingcloset.com/2014/09/22/the-beginners-guide-to-annie-sloan-chalk-paint/