<tr *ngFor="let ... of ...; let i = index">
// you can use {{i}} then to get the number of the row
// e.g:
<tr *ngFor="let adjustment of adjustments; let i = index">
<td *ngFor="let blade of blades; let j = index">
<span> Counter = {{ (i * blades.length) + j }} </span>
</td>
</tr>