seems a strange thing to have to ask as you can buy drain rods at any builder merchant or the diy stores in the uk  but can anyone tell me where i can buy a set of drain rods in or around bangkok or anywhere else in thailand for that matter .any help will be much appreciated 

This subject was on here not long ago.

 

I made my own from lengths of 1/2in water pipe. It's strong enough to push through the pipe yet flexible enough to do the job.

 

I cut the handle of a toilet brush to use at the business end and screw connectors to join lengths together.

 

Make sure to glue everything so it does not come apart in the drain.

 

 

Works great

Gotta admit, I'm not a plumber by trade, so I'm just offering up a rube's idea:

 

I've always used sewer snakes (or plumbing snakes) as opposed to a drain rod.  I'd be concerned the PVC pipe would get stuck and break off 10-20 meters down the line and that would make the fix much worse than the original problem.

 

Another bonus, sewer snakes are pretty ubiquitous in Thai hardware shops and I've seen street kiosks around Chinatown that have them as well.

 

To be clear, here's what I'm talking about, along with the industrial grade version:

 

Home Pro sell's what is pictured in the post above.