How to reinforce shower pan threshold?

[127bit]

The left rear floor corner is highest (the shower pan touches/sits on the floor), sloping down diagonally to the front right corner (lowest). The front right corner shim is 5/8", the left front corner is 3/8" shimmed, with shorter shims under left middle and right rear corner.
The pan perimeters are level and ready for the mortar to be applied to the underside. However, I don't know how to support the threshold flange, especially as the gap below it is a gradual wedge shape. I think that If the threshold is not properly supported, it would begin to crack as it is periodically stepped upon.

1. Should I form a mortar mini-curb to be vertically flush with the threshold to avoid trapping water on a 'step'.
2. Would forming a mortar mini-curb at that location not gradually wick water under the pan?
3. Would stepping on the threshold not eventually crack the mini-curb?

Advice here will be most appreciated.
Thank-you

 

[ShaunCorbs]

You need to set the tray in mortar as it’s not designed to be floating

 

[127bit]

You need to set the tray in mortar as it’s not designed to be floating

Shaun, thanks, for replying. I did mention the pan was ready to be set in mortar. I'm uncertain how much mortar to use at the threshold, protruding distance, slope, etc, since it will have to be higher than the floor for it to be level.
Thanks.

 

[ShaunCorbs]

Shaun, thanks, for replying. I did mention the pan was ready to be set in mortar. I'm uncertain how much mortar to use at the threshold, protruding distance, slope, etc, since it will have to be higher than the floor for it to be level.
Thanks.

What waterproofing method are you using

 

[127bit]

What waterproofing method are you using

If you are asking about walls - cement board. This is a basement so no wood underneath. I can fill the underside with as much mortar as it can accommodate, but I can't determine the best way to neatly terminate the mortar bed at the bottom of the threshold in terms of its protruding distance, slope and water resistance.

 

[Timmy D]

Check the instructions, some allow wooden batten to be glue into the lip before the tray is bedded down.

 

[127bit]

Conclusion: I stuck a strip of painting tape along the threshold, flush with its bottom edge. Then I set the bed of mortar including a curb about 1.5 inches deep straddling the threshold bottom. Levelled the pan, waited about 2 hours, then scraped the excess curb away, leaving its face flush with the threshold bottom. After its fully dry I'll pull the tape off and probably press a bit of caulking along it once I've got the floor prepped later. Thanks to all who suggested.