Spotting paste??

[challenger]

I've seen videos of some scraping and one guy talks about making a paste from mortar colorant mixed with spindle oil. Anyone use this for Spotting dye?
I've used permatex Prussian blue which isn't ideal so I'm looking for alternatives. The other popular stuff is canode but it isn't very available. Thanks

Galaxy S4, Slimkat
If I wasn't married I'd quit fishing

[Normanv]

In the past, when scraping a surface, I have used any oil paint that I happened to have. It's ok but messy.

[Frank Ford]

Dykem Hi-Spot is the stuff I've used - no complaints here. . .

[TGTool]

Forrest Addy has talked about the possibilities for DIY spotting compound. Some stuff is more appropriate than others. You want something with a small enough particle that it doesn't materially change the spacing, and one that's not abrasive which relates to particle shape. I forget what ones he thought might work. Red lead has desirable characteristics except for that one undesirable bit about being toxic.

If you searched posts you can probably find that discussion since it's been hashed over before.

And why is Canode not available? They don't ship to NC for some reason?

[Westline]

I also use and have a distaste for prussian blue .... It lasts forever but damn it gets on everthing.
You can use any oil or coloured grease really just make sure its not too runny and as thin as possible.
I would not try axle grease since everthing will show up as a high spot.
Once I used blue packing grease at one of our moulding shops to show the operator the dent he created in the mould ( low spots)
Just steer clear of any powder colour since if it does not dissolve it will be like dust or sand on the surface plate and give a false reading.
Just an idea "have not tried it " but silicone grease and food colouring or dykem might work.
Let us know what work if you don't mind

[Peter.]

You can buy Stuarts micrometer blue off eBay from UK vendors who will post to the States.

[challenger]

Thanks! I can get Canode if I order it t from the source but I'd like to get it from a more local supplier which has not been possible. It's the shipping that makes it cost so much and I'm J St trying to get a feel for scraping and put in only a small investment.
I've tried some powdered paint pigment with no luck. I mixed it with linseed oil and it was a great color but didn't transfer with a hoot. It was even difficult to spread out with the brayer and sort of smeared without sticking in spots.
I am aware of the particulate/abrasive issue BTW and it's a good point. Everything I've tried has been extremely fine and has dissolved. Still have not gotten anything to a paste consistency.

Galaxy S4, Slimkat
If I wasn't married I'd quit fishing

[TGTool]

I gave you a clue.


http://www.practicalmachinist.com/vb/machine-reconditioning-scraping-and-inspection/pigment-colors-printing-your-surface-286996/?highlight=forrest+Addy

Read and assimilate.

[J Tiers]

You DO NOT want it in oil.

You PARTICULARLY DO NOT want it in linseed oil. Linseed will "cure" even in the raw state, and become a "paint". It's normally processed to improve it's "drying" capability, and boiled linseed "dries" faster.

Try a grease instead. Greases will usually be much stickier, and they will also thin out as a coating when rubbed.

[challenger]

Thanks. I'll give that a try. I still have some Prussian blue paint pigment and some red lead paint pigment powder that I'll experiment with.

Galaxy S4, Slimkat
If I wasn't married I'd quit fishing

[Yondering]

Hey guys, I have no experience with scraping so this might be a terrible idea, but had a thought that might work:

Polyester powder coating is made of very fine polymer dust that will dissolve in acetone or laquer thinner (and probably other shop solvents, maybe brake cleaner). This results in a very thin colored mix that will dry up (how fast depends on the solvent, but slower than acetone or laquer thinner by themselves), but when dry can be wiped off again easily with solvent on a rag.

Maybe helpful?