I really want a beginner scraping project!!!

[GA Gyro]

When I was researching scraping and oil retention the the only peer-reviewed paper I found on the subject concluded that the optimum surface had .1" dia by .001" deep round-bottomed dimples burnished into it so as to cover 25% of the area. This resulted in a 25% reduction in wear compared to a ground surface. Thus the best thing to do is to go over your ways with a ball-peen hammer and then stone out the ridges.

I'm not about to try it.

That does make sense... however... I agree... not on my machine... unless someone else shows me it works.

Funny how that goes...

 

[GA Gyro]

Just wanted to say THX to all the folks who posted comments on grinding and scraping ways...

This is something new to me... I truly appreciate the sharing of understanding... :thumbsup2:

Love to learn!

John

 

[Ulma Doctor]

Could you explain oil flaking?

flaking is a different method of scraping, you will see rows of a half moon looking pattern.
it can be produced by hand or by dedicated biax scraper.
the motion of the tool is slightly different, for lack of better descriptive powers, it has a dishing/gouging motion that produces heavier grooves in the intended material that trap an even greater volume of oil.

 

[John Hasler]

flaking is a different method of scraping, you will see rows of a half moon looking pattern.
it can be produced by hand or by dedicated biax scraper.
the motion of the tool is slightly different, for lack of better descriptive powers, it has a dishing/gouging motion that produces heavier grooves in the intended material that trap an even greater volume of oil.

Ok. I thought that "oil flaking" referred to a different method of flaking that somehow involved the use of oil.

 

[astjp2]

Considering I am less than a year away from my doctorate, I can honestly say that true craftsman like Richard King probably will not publish a peer reviewed article, they will write a book. His course and the Connelly book are two of the most relevant sources on this subject that comes from generations of trial and error. Most PHD candidates don't give a .... about the amount of oil is scraped vs ground ways because researching it is not adding to the body of knowledge. A masters student may look at reducing friction in a body for a project that is evaluating a machining process or machine manufacturing technique but PHD candidates are looking to continue someone else's work that is considered ground breaking and way scraping probably is not the hot topic of the 21st century. Tim

When I was researching scraping and oil retention the the only peer-reviewed paper I found on the subject concluded that the optimum surface had .1" dia by .001" deep round-bottomed dimples burnished into it so as to cover 25% of the area. This resulted in a 25% reduction in wear compared to a ground surface. Thus the best thing to do is to go over your ways with a ball-peen hammer and then stone out the ridges.

I'm not about to try it.

 

[John Hasler]

Considering I am less than a year away from my doctorate, I can honestly say that true craftsman like Richard King probably will not publish a peer reviewed article, they will write a book. His course and the Connelly book are two of the most relevant sources on this subject that comes from generations of trial and error. Most PHD candidates don't give a .... about the amount of oil is scraped vs ground ways because researching it is not adding to the body of knowledge. A masters student may look at reducing friction in a body for a project that is evaluating a machining process or machine manufacturing technique but PHD candidates are looking to continue someone else's work that is considered ground breaking and way scraping probably is not the hot topic of the 21st century. Tim

Tribology and lubrication are active areas of engineering research. Surface treatment is an important part of that. The question of what degree and type of roughness minimizes wear is quite interesting to machine tool manufacturers.

 

[astjp2]

That maybe true but scholars are not publishing journal articles on this topic, if they were, there would be more. Engineers are more likely to publish in a trade magazine to get this information out as a sales pitch on a product they developed or a new fandangled whoopdeedoo that they are selling. Not many machinists are going to look at the American Psychological Association, but they do paruse Modern Machine Shop. We get that magazine at work and it does provide excellent information on new products and techniques or new ways to look at old ideas. Tim

Tribology and lubrication are active areas of engineering research. Surface treatment is an important part of that. The question of what degree and type of roughness minimizes wear is quite interesting to machine tool manufacturers.

 

[John Hasler]

That maybe true but scholars are not publishing journal articles on this topic, if they were, there would be more. Engineers are more likely to publish in a trade magazine to get this information out as a sales pitch on a product they developed or a new fandangled whoopdeedoo that they are selling. Not many machinists are going to look at the American Psychological Association, but they do paruse Modern Machine Shop. We get that magazine at work and it does provide excellent information on new products and techniques or new ways to look at old ideas. Tim

Faculty at engineering schools publish in peer-reviewed engineering journals. And I noted that I found only one paper.

 

[DMS]

This may seem like a waste time....
But, consider just getting some cold rolled steel and making 123 blocks.
They'll have plenty of uses for blocking on the bandsaw or drill press later.
Regardless, if your first scraping looks anything like mine, then you will want little investment as you walk it to the scrap bin.

Daryl
MN

I made a dovetail slide from mild steel stock. I have to say I wish I had used a different material. The steel was soft and gummy, and difficult to scrape. It also isn't a very good bearing surface. If you are making tools you want to use, I recommend spending the few extra bucks for some cast iron. I did this for a 55 degree prism I scraped, and the results were much better, and the work was much more pleasant.

That being said, I did use a piece of mild steel for the base of a small surface gauge I made, and while CI would have been better, I am sill using the existing base, so it is doable.

 

[benmychree]

flaking is a different method of scraping, you will see rows of a half moon looking pattern.
it can be produced by hand or by dedicated biax scraper.
the motion of the tool is slightly different, for lack of better descriptive powers, it has a dishing/gouging motion that produces heavier grooves in the intended material that trap an even greater volume of oil.

I can elaborate on the Biax scrapers; The scraper itself has a recriprocating motion in line with it's axis and uses a thin flat cutting blade that has a included angle on it's cutting face a little less than 90 degrees and has a small radius transversely. The flaker has a rocking motion to the tool, which is curved in both of it's cutting faces, with different radii in three different sizes for small, medium and large patterns; as the cutter rocks, the tool is pushed along at a constant rate, that makes the half moon pattern.