Hello everyone.
I am new and nice to meet you.

I'm writing to you because i need sb help.
So...

I have groove to milling (screenshots below - Polish version of software but i try to translate everything).

In options: Max. entrance angle: 1
Strategy: Side

Groove (color red):
fot_1 (I cant put links as new user - uploaded photos using forum)
Dimension of groove: width 24 mm (with -0.5 surplus to 25 mm)
Milling cutter: 25 mm

And what's problem I have:

I fill max entrance angle with 1. A reduce feed to 30 %, but end mill enter into material with 90 deegres and then milling (like drill - it's unaccetable - i know it works but it's good way to destroy mill). I tried a lot of configurations and nothing change.

It's strange because upper groove, simlar to this, the same strategy, parameters, tools is milling correct with normal entrance (with angle).

Wrong way - lower groove:
fot_2
Correct way - upper groove:
fot_3

Everything the same - I have no idea what's wrong and what i should do.

Thanks everyone for help.
If I didn't put enough informations, please tell me.

Greetings,
Paul

I'm not understanding what you are trying to do. If I was going to mill the red area I would use pocket and give it a total stock allowance.

Everything is ok with strategy, but mill entrance not. End mill couldn't enter vertical (sometimes carbide) and it's my problem. I set up entrance angle to 1 degree but it's still wrong. You can see it on screens - the same strategy and similar grooves and another way of enter

You think I shoud change strategy to pocket? Now I am trying to do this in 2 parts - upper and lower groove with 'side'.
Now allowance is on minus (it's not +0,5, but -0,5). It's pump body preparing to welding (0,5 mm clearance for cover).

I hope you understand my idea ; )
Maybe I am trying 'pocket' to do this tommorow.

It looks like you have a bad curve (boundary) with the lower pocket. When you look at the dark blue, the 3 rounded corners to the left, top and right have a straight "tail" attached. There is also something wrong near the bottom rounded corner. It looks like a segment/line is missing. The shape is interrupted. If you look close, the features of fot 2 and 3 are not exactly the same boundary.
...hope this helps.

Problem solved after your tips. Thank you guys.

What I have done.

I made new curve using curve creator (from surface).
After that I change strategy to pocket.
It's what I looked for.

The shape is interrupted. If you look close, the features of fot 2 and 3 are not exactly the same boundary.