”Service Etiquette does this apply to both navy and Marine Corps. Interested planning a wedding and info on sword drills.”

LT Hoover, USN Retired

The same traditions apply to the US Navy as do they do for the US Marine Corps. 
I have listed a few instances and guideline you may find helpful.

Navy and Marine Corps - The Arch of Swords

The arch of swords for weddings is authorized for commissioned, warrant, staff noncommissioned officers, and noncommissioned officers only. The arch of swords ceremony is an old English and American custom, which gives a symbolic pledge of loyalty to the newly married couple from their Marine/Navy family. Only the newly married couple is allowed to pass under the arch.
The ushers normally form the sword detail, however other officers, warrant or staff noncommissioned officers may be designated as needed. Customarily, six or eight members take part in the ceremony. The ushers form at the bottom of the chapel steps, in two equal ranks, at normal interval, facing each other, with sufficient room between ranks (3 to 4 paces) for the bride and groom to pass. The senior usher is positioned in the left rank furthest from the chapel exit.

The swordsmen, usually ushers, seat the guests, and after the mother of the bride has been escorted, will hook on their swords, wearing them until time to form the arch.

It is virtually the same as the Arch of Sabers except for the command "Officers, Draw Swords" rising gracefully to touch the tip of the opposite sword.

Departure from the church

At a military wedding, the bride and groom usually leave the chapel or church under the traditional arch of sabers.
It is preferable that six ushers in uniform perform this ceremony, although many more may take part. Ushers may be in uniform of one or more services.

Rifles can be substituted for the sabers if there is difficulty in obtaining the needed amount. Most military chapels have them on hand, or the couple could check with the local military museum or with the various commanding officers to request the sabers.

The wedding reception

At the reception, if the groom is in uniform, protocol demands that he precede the bride in the receiving line.
The national colors and distinguishing flags may be displayed, exactly centered, behind the receiving line, and if the reception room is large, the bridal couple may want an arch included at the reception instead of during the recessional.

Cutting of the Cake

On command, the saber bearers enter the reception room in formation lining up in front of the wedding cake, facing each other.

The bride and groom leave the receiving line, and then pass beneath the arch. They may pause and kiss, before proceeding to cut the cake. The groom would then hand the bride his unsheathed saber and with his hands over hers, their first piece is cut.

Please note that the information contained in this category should be considered general in nature. We believe it to be a true and accurate representation of some of the customs and traditions for the United States Military. We encourage you to read your military manual for the most complete information, and that information will take precedent over the information provided on this web site. Information provided by individuals and organizations is assumed to be correct.