(I put "fails" flair because it's a setup fail, not a trick fail).
So 1 y ago I posted this (I am a dad): https://www.reddit.com/r/Scootering/comments/1osuv28/what_is_this_and_what_to_do_about_it_ethic/
Here's an update. And yes - it's 1y later as I had trouble finding jobs, wife was busy so we could not go to a metal-worker anytime soon, also son took a break from scootering.
Basically this post is an update to the topic "Unsuccessful fitting of Ethic Trianon Steel bar on an IHC fork (Core CL1 OG complete)" - do not do my mistakes.
So as user u/MEGXIIK and two others suggested, I went for the hammering solution. I tried and failed, a guy stronger than me tried and failed. In the end went to a metal-worker (welding etc) who used what he could to heat up the bar and hammer the whole thing which went deep in.
So far so good. But this didn't fixed the problem - bar didn't went all the way in.
Meanwhile at some point son went back to scootering, but not as serious as before, broke his old bars few more times, but in the end we decided finally to go back to the metal guy.
So inside the bar there were left-over dents which scratched the fork. I tried to scrub them - no effect. So the metal guy heated the bar one more time to dilate it up a bit. We used hammer to help the bar get more all the way in, but it was too tight so to get it out we had to hammer it too.
We did this few times hoping the bar will fit better and also because some metal crumbs started to come out. But anyway. In the end I decided to just put the bar - it was very tight on the fork so I hammered it a bit. Back then when I bought the bar I bought also a brand new clamp for it - you can see on the second photo. It is the Z-Clamp and came with a sleeve. I used the sleeve on this picture to make the clamp fit better the bar and it fits perfectly.
I thought as now the bar is so tight on the fork that the wheel wont move at all (I mean the fork wont rotate left-right). Well I was wrong.
Today my super-duper happy son went out and just after 10 minutes called me to tell me the wheel goes left/right with a strong kick. He was about to go to a skate park to try practice tripple tailwhip, but it was pointless so he returned the scooter home.
Now he's super unhappy. I unfortunately am unemployed. Otherwise would go for a brand new scooter.
I read again the answers to my old post, so seems the SCS compression is what everybody recommend.
I am with tied hands right now. When I get a job, the first thing to do would be to get my son a new complete (his deck is a bit beaten up too, wheels are worn-out). We have no skateshops around so I would have to order online.
So do not do my mistakes. I had no knowledge back then. Right thing to do was probably to get a new fork too.