Max Bit Size Hammer A3-31 Slot Mortiser

I would like to create slot mortises of 3/4 thickness with a Hammer A3-31 slot mortiser. The closest bit Birds Mouth Bit size that I can find online is 20 mm. Is the 3 hp motor on the mortiser capable of handling a bit of this thickness?

I think Felder makes reduced shank bits in 18 and 20 mm sized to fit their 16mm capacity Westcott chuck. You have more than enough power for mortising with that unit: you make successive passes at a reasonable depth increment per pass: no problem. I use end mills but I would think someone would make imperial sized bits in that dimension (?)