I see nok air has a flight that arrives in udon at 7:05am, but is there a mini van to the border at that time? And cars from the bridge to vientiane? I estimate would arrive thai embassy at about 930am, tomrow, is this enough time?

No problems at all. I've taken that exact flight 3 times before and managed to get to the Consulate between 9am and 10am on each occasion. The main limitiing factor is obtaining the VOA for Laos on the other side of Friendship Bridge. That can be slow if there are a lot of applicants.

There's a limousine service at the airport that will take you directly to the Friendship Bridge for 200 baht. The ticket counter is directly ahead of you when you exit the baggage claim area. You couldn't miss it even if you were legally blind.

The consulate will be closed on May 3 and May 5.

Edited April 25, 201016 yr by tropo

So if mission critical you can obtain your Visa from the PDR Lao embassy in Bangkok before you leave... to avoid the odd chance that as kuhn T. says there are a bunch of tour bus passengers who arrive at the brdige the same time as yourself.

The last 2 times I have applied for a Visa on Arrival at the bridge, the immigration card was processed at the same time as the visa. This means that once you get your passport back you can walk straight past the immigration booths and exit the immigration area just by showing you passport to the exit desk. This can save a lot of time if there a big queues at the immigration booths. However if there are big queues at the visa on arrival desk it can be take a lot longer.