Loading a Ceramic or Iron Cast lap with diamond powder or spray. [photo]

[Brian Marshall]

Arnaud, I was replying to the other post about using different laps for different grits.

Never recommended that YOU buy 5 different grits. I certainly don't. (But I'm sure there are those that do...?)



And yes, there are almost always ways to do things cheaper.

(Like you and I were talking about the welder for Ti awhile back. I saved around $500 by NOT buying the PUK.)



I buy 50 or 100 carats of the powder/grit at a time (very cheap) and split off some for students.

By the time I'm done - mine is free...



B.


And I agree, spraying the iron lap with the GRS product will rust the lap.

 

[Arnaud Van Tilburgh]

Thanks Brian for clearing this out to me. I understand your point now.

arnaud

 

[mrthe]

Brian just curious you welding Ti without Puk?

 

[Brian Marshall]

Yep, small TIG works fine...


B.

 

[Arnaud Van Tilburgh]

I just loaded my Iron Cast lap with 1/2 carat diamond powder, perhaps a bit too much at once, but it works great. Piece of cake!
I also put some diamond powder on the leather lap to polish metals, it polishes fast on Titanium too.
arnaud

 

[Dave London]

Brian
More info on the small TIG please. Thanks Dave

 

[tim halloran]

Arnaud: The directions that come with the GRS iron lap describe how to charge it with their diamond spray. You spray the diamond on the lap as it is turning, shut it off, let it dry. Then you pour a little olive oil on the lap, then you work the diamond into the lap with with a small piece of carbide in a circular direction. I was provided with a used piece of flat triangular shaped carbide, a chip breaker made for tool holders used on lathes. Once you have worked the diamond into the lap by hand, you can turn on the hone and work the diamond into the lap while it is running, moving the carbide back and forth as it turns. The diamond in the spray is suspended in alcohol, i do believe, to speed up evaporation. Lastly you wipe off the lap to remove the excess olive oil. The lap is then charged and from personal experience, it works really well to put a razor edge on your tools.

 

[Brian Marshall]

Dave, I found a 1/2 off deal on a small Orion...


B.

 

[monk]

uh, this all turns on my lightbulb. many years ago i got 4 or5 different grades of diamond paste. the stuff has dried out. would you think common mineral oil wouldserve to reinvigorate the stuff ?

 

[Brian Marshall]

Monk,

I have "revived" a few over the years. First you have to determine what the base was. There actually were few water based pastes long ago.

If it's water based, I used a test tube filled with hot water to immerse it in. After 10 minutes or so I got the plunger out. (or was it 10 minutes, 10 times?)

From there it was pretty simple to rehydrate what was left.


For the oil based pastes, I did essentially the same thing, only with warm mineral oil - put the tube in a vacuum chamber for couple minutes.

Then put the tube in a hot ultrasonic to loosen the plunger.


After you get the plunger out, the rest is "easy".

But, I am NOT saying that determining what you have - after 15 or 20 years, and the label is gone as well as your memory - is gonna be an easy thing to do!


Brian

 

[Dave London]

Sweet score, thanks for the info

 

[monk]

mine is in vials. and as you say-- the labels are all but unreadable. i'll end up with perhaps 4 different grits and wont know which is which. i think i could probably put a dab of each on a slide to compare grit size that way.

 

[Brian Marshall]

Whoops, I thought you had the lapidary/facetors syringes...

I'd probly put whichever ever base you think they had - or shucks, just use mineral oil, won't matter for sharpening purposes - in the vials and get them in a heated ultrasonic for a while? Maybe just a coupla drops to start with, see how it goes...

We also have the same problems with the powdered paste solders in syringes drying out. 'ceptin they don't ever use oil as a base!


B.

 

[Arnaud Van Tilburgh]

After loading the Iron lap now, it work just great. But I was wondering how ling it would take before I have to reload it again. It takes a bit of time to have it loaded properly, so it isn't that fast as spraying diamond spray on the ceramic lap.

arnaud

 

[Brian Marshall]

Hey Arnaud,


Pretty much whenever your polishing begins to visibly fail... it'll be different for eveyone.

How many gravers, how much pressure, etc.

Do be aware that iron is very soft compared to ceramic and you MUST keep moving over the entire surface of the lap.

If you stay in one spot, you will put a groove in it fairly quickly... (not a big problem if you have a lathe, I suppose - but best to prevent in the first place)


Brian

 

[Arnaud Van Tilburgh]

Thanks Brian for the tip, I was already aware of the softness of the Iron.

arnaud

 

[silverchip]

Years ago I was wrestling with making some of my own laps. One of these experiments was a steel disk,diamond dust, bees wax and a thinner for the wax. I put a drop or two of dissolved bees wax on the disk and sprinkled the diamond dust on it and spread it on by running the motor and wiping my finger across the disk. When the solvent evaporated it left a super thin film of diamond and wax on the surface. As long as I didn't come in hard contact with the disk with the tool(drop it on and scrape it accidentally) It work very well and lasted for some time before needing to be recharged.

 

[Arnaud Van Tilburgh]

Thanks David, yes seems piece of cake. Funny the way you call it dust.

arnaud

 

[silverchip]

The disk was 3/8" thick, and faced off on both sides with a lathe.

 

[monk]

i too have a solidified silver solder syringe. i;d suppose acetone or some methanol; would work. i'll try it and let you know how it works.