Prussen blue

[GregLaROCHE]

I have a mini lathe that I am going to be tearing down to try and improve the carriage to cross slide functioning. I have ordered a surface plate and scraper, but have heard that today a lot of people use a water based product, that is a lot easier to Clean up than oil based traditional prussien blue. Can someone tell me what exactly it is called and where I can find some? Is it a Dykem product?
Thanks

[Winger Ed.]

You can probably find it on amazon.
Or, certainly McMaster-Carr will stock it.

[GregLaROCHE]

The problem is I’m not sure what the name of it is. That’s what I’m asking help with.
I found something called canode 2243. It that the best stuff to get for what I am wanting to do?

[country gent]

I always used Dykem Prussian Blue I believe the number is 109. The benefit to this is it never dries and as your pattern gets finer the blue gets thinner showing the more prominent high spots. The never dry is a pain as it dosnt feel wet and it gets everywhere if your not careful. a very light coat applied to the plate or straight edge is all you need. A ball from a cotton or flannel rag is what I used to apply and spread it. For the plate I would fold up a length of rag about 3-4 times to about 2" wide and then roll tightly on itself keeping a flat side. Then a piece wrapped over for a smooth flat surface.. electrical tape works good to hold it all together and makes a cleanable surface. hen new it will spread the blue to thinly for roughing unless your very careful once used and "charged" it works great, start with a small dab or 2 of blue then just keep using the ball to spread and thin.

The canodes are water soluble and easier to clean up but they also dry quickly making it harder to pick up spots. I also dont like the color transfer with them. But they used them a lot in die cast.

The inking needs to be read as you scrape. Stone the part, clean your plate of straight edge. windex, alcohol, or plate cleaner. Apply a tin coat of blue bigger than the part. gently set the part side to be worked down and lightly rub it back and forth. lift up when finishing or a heavy coat of blue it may vacuum to the table and be difficult to lift.When you see your pattern the wet greasy looking spots dont touch or very lightly. the blue dry looking spots hit a little harder. the ones that look like an island a bight silver point in a ring of dry looking silver blue are the highest points hit these the hardest,These are the bearing points.

Once each pass is done clean and lightly stone to remove sharp edges and the light burrs or you will scratch and ruin the plate or straight edge.

Each pass should be from a different direction to get the cross pattern desired. then when close to finished a flaking scrapper is used to make the "gull wings" or oil pockets removing the very highest points.

I ground my blades for my biax scrapper with a 2* positive angle and 1" radius.

[GregLaROCHE]

Thanks Country Gent. You are always there with a wealth of knowledge when needed.

[Jeff Michel]

Red lead is real good for spotting if you can find it. Prussian blue is pretty much your best bet currently. I spread mine with a printers brayer and remove the excess with a piece of gauze. If you can find a copy, Machine Tool Reconditioning by Edward F. Connelly is the best book by far on the subject of scraping. I found out exactly what it means to "chase your tail" if your not paying attention. Good luck with your project.

[GregLaROCHE]

Machine Tool Reconditioning by Edward F. Connelly must be a pretty good book. Amazon has it, but it costs $465. Unfortunately, that’s over my budget.

[country gent]

That book can be found in most college book stores that have the apprentice classes. I got my copy at the local college. It is very good and true old school information.

Thank you Greg for the compliment.

[uscra112]

I worked for several years in machine tool rebuilding, where scraping was the norm. Coat one side with Blue, the other side with Red. Will make the high spots on both stand out.

We took a shop rag, rolled it into a tight cylinder, then folded that double to make a "mop". Run a big rubber band around it to keep it together. I think I may still have one or two packed in Baggies.

Another way to make a mop was to fold up felt weatherstripping.

[Jeff Michel]

Machine tool Publications, 92.95 + 6.80 shipping. www.machinetoolpublications.com

[GregLaROCHE]

Machine tool Publications, 92.95 + 6.80 shipping. www.machinetoolpublications.com

Thanks a lot! I just ordered it. It seems a lot more reasonable than the others I’ve seen on sale. I hope it’s a regular book and not just photo copied pages.

[uscra112]

Looks to be same as the copy I bought 50+ years ago.

The truly definitive book on the subject is Foundations of Mechanical Accuracy, by Wayne R. Moore. Unfortunately not published in any quantity, and copies are extremely spendy today. I see two listed on Alibris, at about a grand each. :shock:

[W.R.Buchanan]

I have had a tube of Dykem Prussian Blue in my tool box for 40+ years. The last time I used it was when I had an altercation with an annoying co worker who came to my house and wouldn't leave until I Physically had to throw him out at 2 AM on a work night.

I got to work before him the next morning and coated the inside of his Hard Hat Band with the Dykem Blue and by noon he had a nice 1" wide dark blue band across his fore head which lasted for days! He was pissed but couldn't do anything about it!

Best use for the stuff I ever found, and I still have what's left of that tube in my tool box. We got plenty of mileage out of that episode.

Randy

[country gent]

Works great on the ear piece of a phone to.

[Jeff Michel]

Blends good on black toilet seats....... So I've heard:mrgreen:

[Scrounge]

I have a mini lathe that I am going to be tearing down to try and improve the carriage to cross slide functioning. I have ordered a surface plate and scraper, but have heard that today a lot of people use a water based product, that is a lot easier to Clean up than oil based traditional prussien blue. Can someone tell me what exactly it is called and where I can find some? Is it a Dykem product?
Thanks

I don't remember what it is called, but check out the videos by Richard King, the guy who does scraping classes, and I'm pretty sure he'll tell you what to use. Scratch that, I looked, because I'd forgotten what it was called: https://www.artcotools.com/Canode-Blue-Die-Spotting-Ink.html Stuff made of gold, apparently, but if you can do the things that Mr. King can do with it, it has to worth it!

Bill

[Scrounge]

Thanks a lot! I just ordered it. It seems a lot more reasonable than the others I’ve seen on sale. I hope it’s a regular book and not just photo copied pages.

The link Jeff Michel gave you is the publisher. It's not a photo copy. I have PDF of that, and two or three of the books by Wayne Moore. Foundations of Mechanical Accuracy is still in print, too. http://mooretool.com/publications.html It's spendy, but at least the the guy who wrote it gets some benefit from it if you buy from his company, and it's not nearly as expensive as the copies uscra112 mentions.

I'm not nearly good enough at machining to need this stuff yet, but hope to get there one day, so I've been collecting...

Bill