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I got two more Swatys today. Instead of using BKF and a toothbrush, I decided to try to kill two birds with one stone. I rubbed the stones with BKF between for a while. It appeared to work up a chocolate colored slurry. If that was what it was did I clean and flatten? Is there a use for this slurry (if that is what was)?
What is a BKF, please,,,,
I thought you knew! i certainly didn't except in a different life it wasQuote:
Originally Posted by Hirlau
Butt Kicking Female
Barkeep's FriendQuote:
Originally Posted by Hirlau
O.K. thank you,,,,, I actually have a can of it under the sink.
Why would you or how did you decide on using this to clean your Swaty?
Mainly because that is the product I use to clean diamond, sapphire hones and high number grit stones. I think it has a bit of oxcalic acid but washes off well in water.Quote:
Originally Posted by Hirlau
I could possibly see the use on DMT plates, naturals like a hard Arkansas that is caked in grease or crud, or maybe a PHIG,,, even that I'm not sure about,,, but a manmade barber hone, I can't see usung that product,,,, but they are your hones & your right to use them as you want.
There two types of BKF, the powder which is used like Ajax or Comet and the liquid which I use on higher grit stones and Barber's hones. It feels like it is only about half as gritty as the powder. Have not noticed any adverse effects.
O.K.,,,,,,,,,,,,,back to your OP,,, I'm not sure you can truly lap the stones by rubbing them together. I would say that you need a standard involved that is truly flat like a DMT or similar.
i was told by an old machinist that granite inspection plates were made completely flat by rubbing two together. i guess they cancel out each others imperfections. not sure if it was true or not.
Could be,,,, but instead of searching out granite inspection plates, I think I'll stick with a proven DMT,,,,,, that's if I lap a barber hone to begin with,,,,:shrug:
Mk 1 eyeball (before cleanup) said they were both straight level and flat. Proof will be in the pudding when I put steel to them. I usually get one shave after the barber's hone then the linen and latigo before the next shave.
Old masochist here. The plates were made by using three of them and a certain order of lapping the surfaces was required to prevent dishing of doming.Quote:
Originally Posted by tintin
Process developed by Whitworth (England) in the early 19th Century and still a final arbiter of flatness to this day.
Good read...for a machinist:
Surface plates.doc
Any side thrust will put pressure on the opposing side. And a figure 8 or similar motion is used while rotating the plate.
So not all old masochists have all the information. I was taught by a real old timer and can't do 1% of what he could.
~Richard
Quote:
Originally Posted by Geezer
Only the Lapping plates by DMT are proven flat..Been fooled too.Quote:
Could be,,,, but instead of searching out granite inspection plates, I think I'll stick with a proven DMT,,,,,, that's if I lap a barber hone to begin with,,,,
This is true.Quote:
Originally Posted by tintin
"Optical Flats" used in laser work are made by rubbing two like stones. The result is a perfectly flat surface.
Assuming similar size, shape, hardness/abrasion resistance you can use three hones to lap each other.. Two stones will not necessarily work, especially if they are didissimilar hones.. As I understand it the three hone lapping method was used by Japanese woodworkers prior to diamond plates.. A laps B, B laps C, then C laps A. Continue this until all three stones are flat..
Two optical plates have been used since Egyptian Times for making lenses by off center pressure and rotation of the top plate..Quote:
Originally Posted by rolodave
History_of_optics
The lapping machines I am familiar with for flats are horizontal rotary plates of large diameter and oscillating and rotating flat plate holders.
Attachment 184422
~Richard
Yeah Richard has it straight. You need to use 3 plates if you want them to end up perfectly flat (or shall we say as near as possible, nothing will ever be perfectly flat). You lap A to B, B to C, then A to C, and keep going until they're flat. Using two plates will get you two plates that are mirror images of each other but not necessarily flat - and in almost every case they will be dished low in the middle on one and high in the middle on the other if you don't do your due diligence on spreading the wear properly and evenly.
I have 3 Swatys, so next cleanup I will use the 3 stone method.Quote:
Originally Posted by eKretz
Wonderful! The air is clear
With a Swaty, there really is only about 6 laps to resharpen the edge of a well honed razor and so they really do not need to be dead flat. A rolling x should be sufficient.
A perfectly straight cutting edge may need special care, though.
Wet Dry abrasive papers on a flat??!! surface is usually plenty for what we need to accomplish.
A second stone may be used to modify another. That is what we do when flattening our hones. If the hone to be flattened is smaller that the flattening stone and a figure eight motion is used the results are usually very good...for our purposes.
And, from my experiences with hones in from the wild, there were a lot of razors honed on badly dished stones and the former owners modified their strokes to have a sharp razor from what we would say is trash.
It is idiots like me that try for perfection and don't have wings who cause all the hype for this or that.
Above all have fun!
~Richard
Rubbing two stones together will make them complementary: the greater the difference in hardness, the greater the curvature. For really flat, you need three stones and that will create a totally flat face. For what we do, two stones will eradicate 'saddle' and 'twist' and thus get 'pretty flat". Also, by happy accident, the complementary curves will typically be a convex soft stone and a concave hard stone. But, in sharpening the soft stones wear in the middle much faster than the hard ones. So the route TO complimentary stones passes THROUGH "flat". Thus, when they 'stick', you're done.Quote:
Originally Posted by tintin
