YASV (Yet Another Scraping Video): Flaking ...

Why aren't ball races, taper roller bearing and linear rails scraped if it's the best surface
Has anyone else ever noticed the identical spelling between Scrape -
ed and Scrap - ed ?
John S.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
John S wrote:

It's the best *gliding*-surface, not rolling surface.
And an ideal fitting surface too. I've read in a book, that the overall damping is by magnitudes better with scraped and oiled surfaces compared to milled ones. That damping has an higher effect than the damping of single parts (cast iron vs. steel).
Nick
--
The lowcost-DRO:
<http://www.yadro.de>
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Tut tut! There's more P in scrapped. Now have fun with that!
Henry
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Yes, frosting does look lovely, can anyone tell me how =it is done ? Any chance of a frosting video Nick ? </boundless optimism>
--
Boo

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Boo wrote:

The "real" frosting is achieved by simply scraping to a plate. With enough passes and short strokes (2 .. 3 mm) it is frosted. Decorative frosting is useless. :-) I do have a cast iron plate that I scraped that looks frosted: <
http://www.cncecke.de/bilder/uploadFiles2008/16348_108072142755_tp2.jpg
For size reference, that a cap of a beer bottle. :-) But I only scraped it to 20 dots per square inches. ;-)
Ha! It floats on the granite plate! Just a slight push and it slides along. Takes a minute or so until it sucks itself to the plate. Took me about 6 hours to scrap (200 * 300 mm).
The other decorative scraping I know of is flowering (we call it "butterflying"). I tried that, but don't have the *slightest* clue how it works. Despite the description in "Machine Tool Reconditioning". One day, I'll find it out too.
Oh, and here's a surface map of that Camel Back: <http://www.cncecke.de/forum/attachment.php?attachmentid 90&d36628659> In fact, it is better, because I didn't subtract the error introduced by my plate (IIRC 4,2 µm). Gonna have to write a program that does better tilting of the plane (another 3 µm) and correct with the known error of the measuring plane. The output is made with gnuplot.
Nick
--
The lowcost-DRO:
<http://www.yadro.de>
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

have you seen this guys work
http://www.lindsayengraving.com/tour/index.html
all the best.markj
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
mark wrote:

Yes, I know. What a waste of time. Decorative scraping the Deckel-clone and leaving the ways worn. :-) No, looks impressive, but honestly I think it's only for the show room.
Nick
--
The lowcost-DRO:
<http://www.yadro.de>
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Wed, 11 Mar 2009 10:51:30 -0700 (PDT), mark

Good God that looks just like my shop except for...........
The quality of the machines The complete absence of clutter The lack of swarf on the floor The missing leak in the roof The missing pile of scrap waiting to be turned or milled into "projects".
But I am happy <G>
Richard
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Richard Edwards Wrote: > On Wed, 11 Mar 2009 10:51:30 -0700 (PDT), mark

Looks like my engineerium too,
but then dawn breaks and I wake up. Ned Ludd
--
ned ludd
------------------------------------------------------------------------
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Wed, 11 Mar 2009 09:48:30 +0000, Boo

Note that what I and Nick referred to as flaking (the half-moons on the work piece) is what Connelly refers to as frosting. and What I referred to as frosting (regular, light scraping patterns like the frost on a window or in a chess-board pattern) is what Connelly refers to as flaking...
After the work is finished, one last pass is made all over the work. A grid is drawn on the work with a pencil 1/4"-1" square as appropriate to the part. Alternate squares are gently scraped over their entire surface in one direction and the other squares are scraped all over at right angles to the first direction. It is entirely a decorative effect, but if done carefully and consistently, it will damage the finish by less than a micron (0.4 tenths of a thou). This is perfectly adequate for the top of a milling machine table:-) No point in doing it on a non-visible sliding surface or a standard, since it'd wear off the sliding surface in a very short time and standards don't need to look pretty.
Using deep half-moon gouging for decoration, as Bridgeport do, just looks like crude butchery to my eyes.
Mark Rand RTFM
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Mark Rand wrote:

Funny confusion. Maybe triggered by me. :-) Or maybe the reason is, that different countries do have different names. I do have my names from the US (and I think I got them right).
Frosting is irregular (90° diagonal) short strokes. Either functional (but with the same appearance) or purely decorative (without flatness) Flaking functional or decorative. flowering, purely decorative (at least never seen on a guide)

I have no word for this. And frost doesn't make a regular square pattern on my car's window (maybe because I don't have a car <G>). I tried that once -just for curiosity- and you even can keep that pattern without a last "destructive" pass. But it's a bit of a pain. Scrap to flatness and then continue with maybe 3 passes -still touching- but keep the scraping direction within the square boxes. Looks very nice.

OK. But then, there are people that can make shallow half-moons (unlike me) that look nice. The ones I made are quite deep. Didn't measure them, but I estimate them to be almost 0,01 mm. Oil pockets should be 6 .. 8 µm for heavy load, about 4 µm for light load.
Nick
--
The lowcost-DRO:
<http://www.yadro.de>
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I think that Connelly is wrong on this one! While frost does not make exactly square patterns on windows, it can make similar patterns with different areas. Another example is the pattern of the zinc crystals on galvanized iron. Again, it isn't regular, but that is the general appearance.

I think that flowering is engine turning by hand :-)

I had been trying to explain the principal without trying to convince anyone that it could be done without damaging the accuracy. There are examples of the manufacturer's name/logo being made in the centre of the surface table using this technique :-) Note:- I haven't tried it myself, it's enough work getting things flat without decorating them as well!

Every time I look at a Bridgeport I get angry about the mindless damage :-(
regards Mark Rand RTFM
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Mark Rand wrote:

Ah, now I know what that pattern looks like: <
http://www.cncecke.de/bilder/uploadFiles/7642_108072142755_schaben1.JPG
Not mine, and not the best according to the scraper. Rectangles are about square and 2 .. 5 mm long. Scraped in 45° directions.
Yes, its a bit destructive, but not that much if you touch and modify the pressure at high spots.

I wouldn't buy a Bridegport anyhow. It's like the Robinson for helicopters. Works, but ugly. :-))
Nick
--
The lowcost-DRO:
<http://www.yadro.de>
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Nick Mueller wrote:

Added two more about the Myford:
Part two (the Vee) <
http://www.youtube.com/watch?v=O-R0c-Xa8mA&feature=channel_page

Part three (a fitting surface) <
http://www.youtube.com/watch?v=IovsVVNu6vY&feature=channel

Nick
--
The lowcost-DRO:
<http://www.yadro.de>
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Nick Mueller wrote:

... part 4: <
http://www.youtube.com/watch?v=-g0Ie1l_nfs
It's about the Myford's table and using the bed as the master.
Enjoy! Nick
--
The lowcost-DRO:
<http://www.yadro.de>
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.