installing string in PVC

[mm11]

I've used this Gardner-Bender CO2 system and rarely had problems. Slight pressure does have to be maintained on the poly-line or jet line to feel the travel; if there's a blockage, the string can jam inside the raceway and become very difficult to pull back out. The rubber piece on the end of the hose has a small metal tube to feed the string through.

http://www.amazon.com/Gardner-Bender-JO225LC-Conduit-Fishing/dp/B008KKSFUY

 

[renosteinke]

I get my 'jet line' from a local tool shop, one that caters to the trades. You know, the sort of place that opens at 6AM and closes at 4PM, and forget about weekend hours! They let me buy them individually. There are larger diameters available too.

I suspect you can get them off the internet.

As for compressors .... so far, I've always had 'house air' available. IMO, it's not the pressure as much as the volume of the air. One customer had a 'bounce house' for the kiddies, and I suspect that the high-volume, low pressure blower that heused would work great for our purposes. I have not tried it, though.

As for vacuums, my little DeWalt 2-gal. vac works fine. So does any "Shop Vac." The hard part is knowing when the string has arrived; sure could use a clear nozzle!

I have installed the string as I assembled the pipe for long runs, but this can be tricky. Here is where you really need to be sure the glue inside the pipe is completely dry, or the string will be stuck.

 

[kwired]

I have used this type of compressor before to blow lines. But I wonder if a small compressor has enought air flow (CFM) to do the job fast. What type of compressor are you referring to?

Larger the raceway the more important the volume of air becomes. While pressure has some importance we are talking about difference between a few inches of water column on the low end to just 15 or 20 PSI on the high end being all that is necessary to push your piston through the pipe. If your blower/compressor can not deliver the necessary volume the pressure is going to drop, if a high volume is readily available you will move the piston at a high velocity, and it may just be what is needed to move past the occasional spot where it will hang up at a low velocitiy.