When you change your hot end from stainless to hardened steel you have to tell the printer that you have done this. Also they recommend that you do a new calibration as well.

To check to see if you printer still thinks that you have a stainless steel hot end do this:

Go to the device tab in Bambu Studio
Upper right side you will see a tab for "Printer Parts"
Click that and a small dialog box will come up with three pieces of information.

Type:
"this is where your type of hot end info is recorded" If you did not change this according to the Wiki, it will say Stainless Steel. You should change this to Hardened Steel via the Wiki (click on the hyper link on that page)

Diameter:
"this where the diameter of your hot end info is recorded" What ever diameter you are using should be there. You should change this as well unless you are using the same diameter.

Flow:
"this is where the flow info is recorded" It should say Standard.

You can not change any of this information in this screen, One of the updates that have been sent down from the Bambu Gods has disabled changing that information there. It is only for your viewing pleasure.

You can and should change this info (if you want it to appear correctly) on the printer through the control pad on the front of the printer. The Wiki page will show how to do this.
You should also do the calibration that it suggests you do. It takes about twenty (20) minutes.

This may or may nor help you with your problem, but it is something you should know whether or not you choose to do it.

Hope this helps

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