Iron cast lap trouble

[mrthe]

Hi, i have a friend in Spain that have a problem with the iron cast lap, he say me that after charge with the diamond spray at the 5 minutes the lap become rusty.
He are doing something wrong?
I don't use this type of laps and i haven't experience with it, suggestions?

 

[sam]

As Arnaud suggested, diamond powder works much better and doesn't cause rust. That's what I use on my cast iron lap now

 

[rayf24]

This has a water based medium to carry the diamond grit which is causing the rust as Sam said use powder or a diamond paste which isn't a water based medium.
if he uses the power put a very thin layer of vaseline or a little fine machine oil this will hold the powder and is not so wasteful of powder and can be wiped clean if needed with some spirits.
Ray

 

[mrthe]

Thank you guys!

 

[DakotaDocMartin]

You can also buy the diamond already mixed with a grease in color coded syringes. Any place that sells supplies for lapidary and faceting will have it. It's typically available in standard grits from 600 to 100,000. And, there is no risk of rusting the lap.

 

[fegarex]

Here are the instructions to properly charge a new lap..
Lap instructions
This should keep the lap from rusting. Much like a cast iron pan it must be "seasoned".
Also, the diamond spray is different for the US market than it is for the export market. The export spray is NF (non-flammable) or water based for shipping rules.
Hope this will help.

 

[Southern Custom]

Those sprays work fine for ceramic laps. Iron, not so much.

 

[DKanger]

He might also obtain some water soluble oil and add several drops to his spray bottle. WSO is used by machinists as a cooling solution and to carry away chips during certain operations. A trip to a machine shop might score him a small vial for a couple of centavos.

 

[scott99]

HI, thanks to mrthe fo the question, and thanks to everyone for their tips they really cleared away the fog for me. Thanks to all.

scott99

 

[DKanger]

I might also add that if WSO cannot be found, you can also pick up a jar of Bar's Radiator Stop Leak at the auto parts store. Disregard the rabbit pellets in the bottom and do not shake the jar. The brown liquid is WSO and was added to lubricate water pumps and condition the internal parts back when engines were still made from cast iron.

 

[LVVP]

As Arnaud suggested, diamond powder works much better and doesn't cause rust. That's what I use on my cast iron lap now

I use powder as well, very good result