Cement/sealer needed for flue collar?

[Jeffress77]

I have just installed a new stove.
I crimped the main pipe at the base for the flue collar. I have a good 1.5” that has penetrated down into the collar and it’s secured with screws. This setup has excellent draft, so I don’t foresee any issues at all, but my question is should I seal the collar where the pipe meets? You can see some visible crimping.

I notice every European/UK video or instructional shows cement/silicone/tape sealer here, but the USA directions rarely do, if ever. The instructions from Vogelzang don’t mention it all.

What’s your take?

 

[moresnow]

Why did you not use the factory crimped end to fit to the stove collar?

 

[Jeffress77]

There was no factory crimped end.

Why did you not use the factory crimped end to fit to the stove collar?

There was no factory crimped end. The pipe was actually flared on both ends.

I cut the pipe to fit exactly the length I needed to go from the stove collar to the 90 elbow. And then cut another section for the short horizontal run from 90 elbow to the thimble/reducer.