Ton-up pair fire Carlton to win
The Edinburgh side looked in serious danger following the loss of three early wickets against Dunfermline Knights at McKane Park.
However, the Saltires duo both hit centuries in a fourth-wicket stand of 225 as Carlton recovered to post a mammoth 348-6.
Mommsen led the way with a sparkling 152 from only 118 balls, hitting thirteen boundaries and six clearances.
His national skipper was not far behind, Drummond finishing unbeaten on 114 with nine fours and a six.
The Knights never threatened the target, limping to 223-6 in reply with Steve Smidt unbeaten on 62.
Carlton remain locked at the top of the table with Forfarshire who produced their own gritty display to overcome Watsonians at Myreside.
Another Saltires pair, Ryan Flannigan and Ewan Chalmers, both hit half-centuries as Sonians reached a challenging 226-7.
However, while none of the visiting batsmen matched Flannigan's 88 or Chalmers' 66, Forfarshire had sufficient strength in depth to carve out a three-wicket success.
It is unlikely that West of Scotland, champions of the inaugural SNCL more than a decade ago, will be challenging to win the first playing of the 16-team Premiership.
Instead the Hamilton Crescent club, going through a period of transition, may be happy simply to avoid the dogfight which will see the bottom four play off to avoid relegation in the closing weeks of the season.
Having secured just one victory from their opening four fixtures, yesterday's clash with newly-promoted Stoneywood-Dyce took on extra importance especially since the Aberdonians had an extra victory in their favour.
However, instead of providing a morale-boosting win, West contrived to throw a position of real strength.
Chasing 172 for the points, the Glasgow side had moved to 121-3 from thirty overs and victory was theirs for the taking especially with Stuart Murray and Anjun Luthra established at the crease.
However, a dreadful batting collapse, sparked by Elton Willemse, saw the Partick men fall six runs short. Willemse, who finished with 3-32, accounted for both Murray and Luthra having earlier removed the home professional Colin de Grandhomme.
Earlier Stoneywood-Dyce were indebted to 16 year-old Omar Afridi for posting a challenging total of 171-9. Afridi has been a rare participant for the People's Park side so far this season due to school exams but he showed his worth with a fighting 49 - the highest score of the match - while his more experienced team-mates came and went at frequent intervals.The teenager, having stroked seven boundaries, looked set for a deserved half-century until being unluckily run out.
Saltires star Gordon Goudie, the former West player, was the next highest scorer with 21 while Ian Cran was the pick of the home bowlers, striking with his first delivery to remove the dangerous Jan Stander, en route to figures of 2-22 from ten overs.
If West expected to stroll to their target, they were soon forced to reconsider when Goudie ripped through the defences of home skipper Ian Young. When de Grandhomme followed, caught in the slips off Willemse for a single, the Glasgow team were teetering on 18-2.
They appeared to have recovered until that late collapse saw Stoneywood claim their third win of the campaign.
Elsewhere Greenock suffered a nine-wicket loss to Heriot's at Glenpark. The men from the Tail 'o the Bank have sent out an SoS to former professional Tim McIntosh to replace Luke Butterworth who has departed for a tour of duty with Australia A.
McIntosh still awaits clearance from the UK Border Agency and it is debatable whether even the New Zealand Test batsman would have saved Greenock from their third defeat in four games.
The home side had little answer to the Heriot's pace duo of Craig Mackellar and Andre van Niekerk who claimed three wickets apiece as Greenock were bundled out for 114.
In reply Chris Kent hit a rapid 69 as the Goldenacre side raced to a fourth consecutive win inside eighteen overs.
Drumpellier skipper Graeme McLaren's half-century proved in vain as his side went down by six wickets to Aberdeenshire at Langloan. McLaren hit 53 and Asid Mohammed 37 as the Coatbridge side battled to reach 166-6 in tricky conditions. It proved insufficient as South African Gerrie Strydom led the Dons' run-chase with 54.
Stirling remain the only side without a win after Arbroath cruised to an eight-wicket success at New Williamfield.
Champions Grange ended a two-game losing sequence with a five-wicket success over struggling Uddingston at Portgower Place.
Kiwi Warren McSkimming was the home hero with an undefeated 68 as Grange reached their 173 target with eight overs to spare.