Difficulty co-parenting

I’m seeking an honest opinion from someone outside the box ...

My ex and I have been divorced going on two years. We have a 4 year old son together. We have a court order for child support and visitation has already been decided in our divorce decree.

He picks up our son every other weekend, but he’s more than welcome to have our son whenever he wants. My intention is not to take our son away from him. I’m not like that. He chooses to only take our son every other weekend because he has to “work” or has “plans.” He is in the military so obviously when he goes away or works long hours he can’t take him. Majority of the time he just wants the time alone with his new wife or to go out and party.

He’s been away for training for 2 months and will return in a few weeks. Prior to his departure I offered to let him have our son for the weekend and he refused stating he had plans. When he returns I asked him if he’d like to have our son every weekend for the month since he hasn’t seen him in awhile and he refused. I noticed our son goes through behavior changes when he goes for quite some time without seeing his dad so I discussed this with my ex and he suggested to take him for 2 weeks or even a whole month, however, the catch is if he takes our son for 2 weeks he wants half the child support money back, and if he takes him for a whole month he’s refusing to pay child support altogether because he claims he can’t afford child support and daycare expenses. When he doesn’t have his son he splurges his money on sneakers, video games, and going out but when it comes to his son he has every excuse to why he can’t afford to pay for certain things. So that’s what bothers me. Our son is supposed to start pre-k this coming school year and we we’re discussing to change his visitation schedule from every other weekend to every other week. My son will be attending a school down the street from my home , my ex lives about 45 mins away from me. Our son’s pre-k is only 3 hrs (7:45-10:45). My ex works from 6am-6pm. He claimed he would drop him off to school and pick him up. Then bring him to daycare until he gets off work.

MY THING IS, if he can afford after school daycare then, why can’t he afford it now? What’s the difference? When our son needs a haircut he’ll ask me to give him money for it. He pays $250 of child support biweekly so that doesn’t even cover the full two weeks tuition for daycare. I still have to come up with the rest. He makes it seem like what he gives is sufficient enough to cover all expenses for our son. Throughout our marriage, he’s NEVER helped me raise our son nor has he ever helped me financially. If I wanted to work I had to pay for childcare on my own. If my son needed clothes I had to make sure I made enough money to provide for my sons needs as well as mines. HE’S JUST NOW WANTING TO BE A FATHER because his new wife loves and adores our son as her own (which I’m grateful for) and she’s having her first child with him.

If he’s telling me he can’t afford things that come with being a parent, WHY bother taking him full-time?! He doesn’t have the time to raise a child. He works long hours and goes away often for training/deployments.

Am I missing something? Because I’m just not understanding his way of thinking...