Replies

1. 
   JimV | Sep 11, 2006 07:14pm | #1

   2 options I can think of:

   1) return them and buy galvenized pipe.

   2) get out the mineral spirits and wipe until clean.

1. 
   GW52 | Sep 14, 2006 08:37pm | #2

   I used galvinized pipe once, It doesn't hold as well as steel and the clamp slips. Use mineral spirits to clean the pipe off. All of the pipe that I have has black paint on it and the rust is not really a problem. When I am gluing up panels I use wax paper to cover the pipes where the glue line is as not to stain the wood.

   Greg

2. 
   JohnWW | Sep 27, 2006 12:45am | #3

   Philippe,

   In the last few years much of the black iron pipe you can buy in the U.S. has been made in China.  The import pipe often has a glopped on thick black paint followed up by some black oil that would have been toxic waste until they figured out how they could send it to the U.S. as a protective coating on pipe.

   As someone else suggested, wiping down the pipe several times with paint thinner or naphtha and multiple clean rags will eventually get rid of the oil, though it won't affect the paint.  I usually then go over the pipe with my hands and use a file to take off any burrs and paint drips that will cause the clamps to get hung up.  As noted by another poster, galvanized pipe doesn't work well, so it can't be substituted for plain black iron pipe.

   To prevent the pipes from rusting, just give them a coat of something like Johnson's furniture wax or something similar.  The furniture wax can be used on all of your machine surfaces to prevent rust and make stock slide smoothly.

   Common yellow carpenters glue reacts with the iron in the pipe to create a black stain that has nothing to do with either the oil or the paint.  The simplest method I've found to prevent the staining is to set up the clamps for a glue up and then, before you start gluing, run a piece of masking tape down the top side of each pipe where the wood will touch the pipe.  Running the tape lengthwise makes it easy to remove the tape after the glue up is done.  If you wrap the tape completely around the pipe at each glue joint it takes much longer to apply and it is harder to remove.

   Hope this helps,

   John White 

1. 
   pbardet | Sep 27, 2006 01:06am | #4

   Thanks a lot all for your answers.I decided to return that black pipe and try the galvanized ones even though I read that the clamps sometimes slip. On the week-end, I was able to use them to glue a 66"x46" project and not one failed during the set time. And I don't have marks on my project. For now, I have to say I'm quite happy about the switch.