View Full Version : Marking medium for scraping
02-12-2005, 07:03 PM
What's a good marking medium when you're spotting the ways during scraping? I'm not actually doing any scraping, but am putting my small Craftsman 109 Lathe back together, and though this would be a good way to adjust the gibs. Scraping will be left for a later date. I've heard of Prussian Blue, but don't know where to get it. Is there a good substitute that would typically be available at places such as Ace Hardware or Home Depot? Thanks
02-12-2005, 07:32 PM
I like Dykem High Spot Blue Paste! Next time you place an order to Enco, add it to your list.
The nice thing about this product is that the “hues” of blue are easy to read when scraping.
[This message has been edited by Mike Burdick (edited 02-12-2005).]
02-12-2005, 09:00 PM
It seems the paste would be somewhat difficult to spread evenly. It doesn't build up excessively like peanut butter on a sandwich?
02-12-2005, 09:16 PM
working on my lathe one night i tried a sharpe marker w/a litte 3in1 oil.. it worked to some extent, then some one (an old timer machinist)told me to go to michael's or ben franklin (craft store)and get some oil paint. have'nt tried it yet but it sounds like it might be worth a try.
02-12-2005, 09:29 PM
Check the Dapra website. They sell a water based spotting compound called Canode. It comes in the traditional red and blue.
02-12-2005, 09:56 PM
<font face="Verdana, Arial" size="2">Originally posted by eddie6675:
then some one (an old timer machinist)told me to go to michael's or ben franklin (craft store)and get some oil paint. </font>
That would be a artist type paint. Normally that would cost more.
I think I remember some old-timers using soot / lampblack and
raw linseed oil to make your own if you want. Raw linseed oil
is just with out the dryers in it.
I think the last tube of Prussian blue, made by permatex,
was $3.00. Lasts a long time.
Be Safe http://bbs.homeshopmachinist.net//smile.gif
02-12-2005, 10:18 PM
Thanks for all your input. It sounds like the best thing to do is order it online. I emailed dapra about the prussian blue....and their scrapers. I wonder if they'll ever set up an online ordering system, or if I just failed to see it. I'd really like to do some scraping....still need to get a surface plate though, and "the bible of scraping" --> MTR
02-12-2005, 10:31 PM
Permatex makes tubes of prussian blue. Avaliable at just about any auto parts store.
02-12-2005, 10:36 PM
Dykem Hi-Spot. I've tried various water base along with the Permatex oil base. The paste seems like it might be too thick but it doesn't work that way. Dykem will embue a deep stained surface to the surface you are scraping to. In the past the surface being scraped would be coated with a very thin coat of white or red lead. And I mean thin. But now with environmental laws the only substitute we have a product called gear compound, meant for checking the mesh of gear sets. Or denatured acohol. But the alcohol can raise the problem of temperature problems causing problems. But the alhocol problem is from the Connely book
02-13-2005, 12:04 AM
For those of you who use the Dykem Hi-Spot Blue Paste, you say it's water soluble? I see in Enco's catalog that they also sell Dykem Layout Fluid Remover right next to the paste (pg 174). Anyone used this stuff to remove the paste? Or actually, is it difficult to remove the paste with water?
02-13-2005, 12:47 AM
The Hi-spot blue does NOT remove with water.
One small spot of it will cover both your hands, and the work, with blue.
The tube leaks it out even when "tightly" closed.
I have quite a bit of it on me right now, and all I did was move the &^%#&^% tube of it to where I will want it tomorrow. There is more of it on the bench under where it was sitting.
I hate it, but I haven't found Canode blue or red, so I use it.
I did find out that rubbing alcohol will remove it, however. From skin, but not from under fingernails.
[This message has been edited by J Tiers (edited 02-13-2005).]
"One small spot of it will cover both your hands, and the work, with blue."
That's for sure. A little goes a very long way! Build-up isn't a problem; you can smear it out to a very thin stain on the surface you're scraping.
Note J Tiers' tip about denatured alcohol. You'll need it!
02-13-2005, 09:52 AM
Used to get parking tickets all the time in front of my house. Got some non drying dykem and carefully smeared the drivers side wiper blades. Well were sittin in the living room drinkin beer and along comes the ticket dude. He writes a ticket grabs the wiper and while were laughing like hell proceeded to try and wipe his hands on anything he could to try to get the dykem of them. HaHaHa Yeah i know im mean but too bad, I havent had a ticket for quite a while now,
02-13-2005, 10:01 AM
Don't know about Dykem stuff, but I get the Canode from a local supplier. Dapra sells the same stuff but I think it is relabeled.
Canode will stain your hands, and generally takes about 1 to 3 days to disappear. When I reconditioned the 12"CK, my hands were red and blue for several weeks, at least the staining was barely noticable.
02-13-2005, 12:17 PM
The Canode material can be removed from your hands pretty well by the following series of cleaning - first hand cleaner, then good hand soap followed by a rinse in household bleach. You will probably want to follow the bleach with more soap - but by that time most of the stain is gone.
02-13-2005, 12:48 PM
Of course there is the Dapra web site
02-13-2005, 01:32 PM
spin doc - thanks for that Dapra link. My previous attempts to reach them failed!
02-13-2005, 11:29 PM
I recall Forrest once suggested coating your fingers with vegetable oil before scraping....the idea being that the oil will prevent the Dykem blue from soaking in.
I tried it, and it does work....when I remember to do it. Better than not doing it...actually makes a fairly large difference.
You still won't be "clean", though, even after washing.
03-29-2005, 10:05 PM
Having scraped a few machines in my time, may I suggest using "tinting colors" found at commercial paint retailers ( like Sherwin Williams or Pittsburg Paint) Comes in squeeze bottles, inexpensive, amd applies as good as the old red lead. Alittle goes a LONG way. Easy cleanup. My favorites are a combo of dark blue and yellow that gives a high spot of green.
03-30-2005, 09:19 AM
I use stencil ink for heavy scraping and Marks-a-lot for the fine stuff.
If you coat a part with marks-a-lot and file/scrape it off you have only removed .0001",works good.
03-30-2005, 10:55 AM
If you can get a little selenium toner from a spent toner cartridge (for a copy machine), take that and mix it with some cold creme (like women use on their face). Makes a pretty good spotting compound, but doesn't clean up much easier than the prussian blue. Also, it's black, so it may not suit you as well.
03-30-2005, 06:20 PM
I picked up some of the Dykem High Spot Blue paste suggested, but haven't yet had the pleasure of getting my hands stained yet. I plan to level my lathe this weekend and then use the Dykem to see where my tight spots are when trying to adjust the apron for a reasonable sliding fit.
Would scraping the ways on a Craftsman 109 lathe that has been "leveled" to a piece of 8" steel channel be a poor choice to learn how to scrape on? I wonder if the lack of rigidity would be more confusing when taking readings? I've heard people say the bed of this lathe is a bit more "limber" than most.
One last question. Will this stuff stain the paint on my lathe? (I just painted it with (Rustoleum "Industrial" dark machine gray)
Thanks for all your input
Your Old Dog
03-30-2005, 06:54 PM
When I was engraving guns I used a product from Brownells called "layout solution" It is white and when spread thin over a 4 or 500 grit surface it makes a good writing surface. No reason it would not work for spotting. It is permanent until you hit it with denatured alcohol that I kept in a small spray bottle for that reason.
I believe that a typest "white out solution" is the same product as they smell the same to me. Put one drop on and spread and rub quickly with a finger.
If it matters, I'm told that dykem and other similiar agents are actually diluted potassium permanganate. It works great to "tique" a maple gun stock to make it look ancient with natural patina!
[This message has been edited by Your Old Dog (edited 03-30-2005).]
03-30-2005, 07:19 PM
A couple of things you might keep in the back of your mind. You may know this already - so please don’t be offended.
Before starting scraping a lathe, be sure you know EXACTLY what and where the problem is. A lathe is a machine that is composed of many items that all contribute to the final tolerance it is able to achieve. To properly scrape a lathe one needs “standards” to scrape to so that the final job will increase the accuracy, not decrease it…
If you have read Connely’s Book, “Machine Tool Reconditioning”, you will have noticed that almost 95 percent of it concerns making test bars etc. for measuring and setup for a particular model. When repairing machines, one can’t say, “I THINK this is the problem” they MUST be able to say, “I KNOW this is the problem” before ever touching anything with the scraper.
A machine can go thru 30 years of hard use but in can be ruined in minutes with an uninformed scraper.
Be careful and think and rethink everything before doing anything. This is not a job for haste!
03-31-2005, 12:11 AM
I have not read the book -- yet. I plan on purchasing it, but at $92.70 plus shipping, it's gonna have to wait a little while yet. I do not intend to do any scraping at this point -- I don't have the proper tools, not even a surface plate or bench grinder.
I was just wondering if this type of lathe is something that might be good to learn on. Since it's not a particularly valuable piece, I wouldn't be too paranoid digging into it. Probably better to get it up and running for now though -- It's currently my only machine tool, and I haven't made chips from an actual machine tool in nearly a year now. I feel like an alcoholic who hasn't had a drink lately.
I use to have it so easy -- program the BP EZ-Trak in MasterCAM and out comes a reasonably accurate part with very little effort. (I used to oversee students work in the machine shop at college, and got to do lots of one-off projects, and had access to a retired machinist to help with all of it).
03-31-2005, 03:02 AM
My post wasn’t meant to discourage you - I just wanted to remind you the importance of not making hasty decisions. I personally think it’s great that you are interested in learning this!
One thing for sure though – when you get your lathe finished, you’ll have something to brag about - and deservedly so!
Regarding Connely’s book: Have you tried your local library? If they don’t have it they can check other libraries and if they find it they will get it for you. My local library does this free of charge - they call it an “inter-library loan. By the way, that book doesn’t really tell one how to scrape but rather gives a good overview of what is involved in and needed for machine reconditioning. It’s pretty “dry” reading!
[This message has been edited by Mike Burdick (edited 03-31-2005).]
03-31-2005, 06:50 AM
<font face="Verdana, Arial" size="2">Originally posted by Mike Burdick:
By the way, that book doesn’t really tell one how to scrape but rather gives a good overview of what is involved in and needed for machine reconditioning. It’s pretty “dry” reading!
[This message has been edited by Mike Burdick (edited 03-31-2005).]</font>
Dry doesn't begin to describe it. Arid, almost lunar in terms of the liquidity of its prose. But if one is setting about reconditioning an old lathe mill or grinder it is invaluable.