lol it was meant to simply show a gap between the top of the stem (handlebars in the 218 case) and the steerer tube.
Yep I would sand down the crap top cap or run the carbon one. Did you try assembling per my steps?

I will try the advice of increasing the gap by one 5mm spacer and see how it goes. Also I can't really follow your steps exactly as I would need to disconnect the front hydraulic hose to remove the fork from the headtube but I guess it's fine installing and fully tightening the plug after fork and spacers are already installed.

But I will definitely try to tighten the top cap before clamping the stem although I guess it doesn't really matter. I will also try to apply some carbon paste on the plug to make sure that thing doesn't move up inside of the steerer when tightening the top cap.

EDIT: OK I tried to add the spacer and it indeed helped. No more headset play. Allright, time to shorten the steerer. Wanted to shorten it anyway to remove all the spacers. I was too much conservative with them. I noticed with 3,5 cm spacers my handlebar is almost 5 cm higher than my current bike. Without them it will also look much better. Thanks everyone for help, especially those that told me my steerer might be too long.

Already ordered 2 more caps with screws they declare to fit 100%. Let's see...

I think people sometimes use plumber's tape (teflon) for loose bearings, electrical tape sounds ghettoer / maybe too flexy?
Btw, if your bearing really is swimming in its hole, then post a video, you may get a new frame. Some play might be acceptable, but if they botched it, they botched it.
It's safe to try the bike with a little play. Don't over do it, dont take it offroad, dont go down a mountain pass, be sensible.

I wouldn't say the bearing was swimming but without the tape it was loose enough to drop from the frame in Earth's gravitational field... The play was corrected by just one layer of that very thin electrical tape...
Already ordered PTFE tape but to apply it I will need to remove the fork from the frame, thus disconnecting the hydraulic hose from the left lever and possibly need to buy a new olive. I use SRAM brakes and levers.

Bike almost finished, but I have issues with a headset play. Any recommendations on what I should do to fix this, as I am not really familiar with headset shenanigans. Some background:
- I've already replaced the original short compression plug with an extra long version (80 mm, not that I expected it will help, I did it mostly for other reasons).
- Also already tightened the plug to max recommended torque for this frame (6 Nm). The integrated handlebar with carbon paste applied tightened with the grub screws to around 3,5 Nm fits firmly already but I guess that's not relevant for a headset play issue?
- The cap on top of the stem I tightened with low torque (around 2,5 Nm) as I believe that's just for the cap to not move and it's not important for the headset itself or am I wrong? (The manual for Dogma says to preload to 2 Nm and then 6 Nm max, but I seriously don't understand why, as the cap is installed as a last part to just cover the stem, so why even preload it? I think the expander plug has to be preloaded before installing the stem or am I wrong again?
- My uneducated guess is the headset play may have something to do with the fact the bottom bearing didn't fit the headtube firmly and there is some play because the headtube seems to be a little wider than it should at the lower part. The upper bearing fits firmly. Top and bottom bearings on this frame are interchangeable and when I swapped them then again bottom bearing is loose and top fits firmly. This means that bearings should be both fine and correct diameter.
- To make the bottom bearing fit firmly too I wrapped it with electrical tape to increase its diameter slightly. This helped with the play during installation but maybe it's not enough after it. Again, I don't really understand how this thing even holds together and why the fork doesn't fall down from the frame...

So what do you guys think? Should I apply glue on the outer side of the bottom bearing like Loctite 638 or should I do something completely different first? And is it safe to ride with a headset play, at least for some shorter test ride or should I resist the temptation to try my new bike?

Does anyone use rim strips with this wheelset? I really struggle to choose proper width. The specs say the wheels have inner width of 21mm. I bought and installed Ritchey 17mm rim strips thinking covering just the middle bent area will be enough as one only really need to cover the holes for nipples. But now thanks to that bending the strip sticks out a little and I am affraid it's sharp edges may damage inner tubes and cause flats. Maybe I should buy wider strips but how wide exactly? I don't want them to get in the way with the tyre beads.

Anyway, my conclusion from this is (and it's pure speculation of course) that the cracks in seat tube actually may have nothing to do with the torque of the grub screws there (since they are not tigtened to the frame itself) and rather are a result of a design flaw when maybe forces that are caused by a rider sitting and riding on a bike are transferred to that area and said area is simply not strong enough.

I am also sad they are stop making this model after they actually listened to some of the suggestions made from customers and thus improving the overall quality. For instance my frame came with all the bolts already screwed inside the frame or handlebar which negates two possible issues - bolts being lost during packaging or transportation and wrong/damaged threads.

Or they changed design of BB area where the BB shell is finally one piece of metal so no more BB facing issues. The screw there is also shorter and so even DUB BB fits.

I probably used 4nm, but I'm not sure. I may have been lazy.

Thanks for answer but... wow, that's kinda heavy torque. I was expecting the measures would allow you to go much lower. It's the maximum allowed torque for the real Dogma F. Someone here did use less (3,5 Nm) and still got the cracks...

This is not the first frame with cracks in a seat tube in that specific area and I cannot fathom why these cracks even appear there in the first place as the bolts are not tightened to the frame itself. The holes are there just to access the bolts and all the force from tightening them should act on the seatpost so if anything the seatpost should crack and not the seat tube.