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Former Newbie Question 'Flaking / Frosting'

Lurk

Cast Iron
Joined
Feb 10, 2014
Location
Peak District UK
Are there any 'rules of thumb' / advice in respect to the density of flaking half moons over a bearing surface ?

I have so far scanned over what must be close to a hundred google images of flaked bearing surfaces / slides and seen lines of half moons anything from several inches apart to touching & over lapping from each direction.

So whats recommended for hand flaking ?

In respect to the depth of these half moons - when I inspect my trials - the thin starting sections are deepest and the wider crescent shallower. I have numerous threads stating the flaking should be around 0.001" to 0.003" deep - is that an average or the range ?

My scraped surfaces have come on, the scrapes measure between 0.0002 & 0.0007" deep depending on how much I leaned on the scraper and how many times Ive gone over the surface from the rough scraping. I have struggled to push flake with any degree of consistency so will be pull flaking bumping the flaker with a deadblow mallet to save my hand.

Be nice to get some advise & I appreciate there are unlikely to be hard and fast rules on the matter.

All comments gratefully received.
 
If your depth is .0002" -.0007" I would say this is a pretty respecable range, maybe a bit light at .0002". But we are all going to have variations.

As far as flaking, you are going to get several different answers here.

When I flake, I keep the pattern about 1/4 apart when I am running parallel.

Then for most projects I go back and double flake it, so I go the opposite direction. Just like when you double cut your grass.

Yes, flaking will be on average .002"

Remember to flake only the moving surface, otherwise debris can get caught in between the ways. This was a a new thing I learned at one of Richard's classes. It made total sense to me.
 
I flaked so the lines were not quite touching.

I have seen many machines over here with the exposed ways flaked, " Bridgeport " milling machines for instance. On the more modern " K-R " Hor bores all the exposed ways were slide ways ground and then flaked. The running elements ( saddle, spindle frame, lower table ) were Ferrobestos lined. They were only scraped for alignment.

I'm not saying that way is right or wrong. I can see that grit can lodge in the pockets of flaking.

Regards Tyrone.
 
I worked with some factory Mattison scrapers. They flaked everything. IMO, they did it because it's easy. They would rough scrape to 1-5 points per inch and then flake. No finish scraping.
 
I heard/read somewhere that your flaking should take away half your bearing so if your at 20PPI, after flaking you should be around 10PPI. Not sure, just a piece of Info that may be useful.

Remember to flake only the moving surface, otherwise debris can get caught in between the ways. This was a a new thing I learned at one of Richard's classes. It made total sense to me.

I find it so ironic that as far as functionality goes, the beauty of flaking should never even be seen by the light of day.

Corey
 
I worked with some factory Mattison scrapers. They flaked everything. IMO, they did it because it's easy. They would rough scrape to 1-5 points per inch and then flake. No finish scraping.

Mattison Flaked the Bases because after Milling them they were not allowed to Scrap them to save time and money. So they just flaked them to cover up mill marks and create the oil pockets. As long as your milling job is good this is really not "bad". But then again, besides my grinders and maybe a few other shops have you ever seen a clean grinder?

It was a really good thing I picked up from the class.
 
But then again, besides my grinders and maybe a few other shops have you ever seen a clean grinder?

Once. It was used to sharpen blades that cut lunch meat. That whole place was spotless.

The Mattison and other grinders don't seem as outrageous as a Bridgeport. At least the grinders have real way covers and filter for the recirculating lube. The flaked ways on a Bridgeport just sit there collecting grime. Pure marketing wank.
 
I dunno if there is anything harder to photograph than scraping. A beautiful job can look like garbage in a picture or on video.

Hand flaking is tricky. You don't get the hang of it until you're almost done.
 
Scraping to large smear areas, or 1-5 points per inch works
If the areas are the same colour indicating they are in the same plane, If we ground a part to a tenth and it proved flat then heavy flaking would make it usable, spotting would show the distribution created by flaking
 
IMG_2681.jpg

Had another chance to get on with hand flaking - pretty much done the Ram and I think thats where Im going to leave it. I have spent hours trying to flake a mock up of the female dovetail where the Ram locates - it being covered and less prone to see debris - failed miserably so left the machine castings alone and opted for the Ram - the results are far from attractive but they are between 0.001" : 0.002" - so functional I guess.

Push flaking remains an enigma - Ive tried to copy videos, even free styled - failed to get anything near controlled. So thats a skill to learn longer term.
Thanks for all the advice.

I would add, after a quite short period of time flaking the Ram - my right shoulder ached a hell of a lot - so I did a quick sum of the mallet strikes - 1200 ! or if you prefer ; 120 rows of 5 crescents x 2 faces. and that's a conservative guesstimate. I imagine a 36" shaper would take some work !
 
Mattison Flaked the Bases because after Milling them they were not allowed to Scrap them to save time and money. So they just flaked them to cover up mill marks and create the oil pockets. As long as your milling job is good this is really not "bad". But then again, besides my grinders and maybe a few other shops have you ever seen a clean grinder?

It was a really good thing I picked up from the class.

I noticed on a quite new Colchester lathe at my old tafe that the crossslide ways were clearly machined with no finishing is this a new cost cutting measure or would this have been done outside of factory. Never actually noticed much of a difference was quite a nice lathe to run just seemed odd
 
Lots of manual machines have gone the same way as CNC with hardened and ground long ways and turcite on the shorter side of the ways. I worked on some Polish made Haco manual engine lathes with turcite on the cross slide.
 
View attachment 203088

Had another chance to get on with hand flaking - pretty much done the Ram and I think thats where Im going to leave it. I have spent hours trying to flake a mock up of the female dovetail where the Ram locates - it being covered and less prone to see debris - failed miserably so left the machine castings alone and opted for the Ram - the results are far from attractive but they are between 0.001" : 0.002" - so functional I guess.

Push flaking remains an enigma - Ive tried to copy videos, even free styled - failed to get anything near controlled. So thats a skill to learn longer term.
Thanks for all the advice.

I would add, after a quite short period of time flaking the Ram - my right shoulder ached a hell of a lot - so I did a quick sum of the mallet strikes - 1200 ! or if you prefer ; 120 rows of 5 crescents x 2 faces. and that's a conservative guesstimate. I imagine a 36" shaper would take some work !

I've never seen anybody use a mallet on a scraper in the UK. Everybody I know and worked with used the " push and twist " method. Some scrape in a straight line at 45 degrees to the ways and some scrape at an angle to the ways but still get the rows at 45 degrees.

It just takes practice. You'll still end up with an aching shoulder though. I have lots of shoulder and lower neck problems these days. I could probably do about five minutes scraping now before the ache starts.

Regards Tyrone.

Treat yourself to a " BIAX " flaker.
 
I've never seen anybody use a mallet on a scraper in the UK. Everybody I know and worked with used the " push and twist " method. Some scrape in a straight line at 45 degrees to the ways and some scrape at an angle to the ways but still get the rows at 45 degrees.

It just takes practice. You'll still end up with an aching shoulder though. I have lots of shoulder and lower neck problems these days. I could probably do about five minutes scraping now before the ache starts.

Regards Tyrone.

Treat yourself to a " BIAX " flaker.
The 'Push & Twist' - I know it should work, I managed maybe a few lines of what looked 'ok' but the majority look garbage and there was more long deep scrapes than curls..... as you say practice would resolve much of it. Its a skill to develop when time permits and I have a decent chunk of CI scraped ready to play with.
I got offered an aged Biax flaker for £450 - £500 including a new unused blade. I had to walk away as I just dont have the funds to invest in it - pretty sure I will kick myself in the near future about that but thats how things go. Right now Im keen to get the machine back together and see it cycle and then start making some chips. ... I might even allow myself a little time to think about the next project !
 
The 'Push & Twist' - I know it should work, I managed maybe a few lines of what looked 'ok' but the majority look garbage and there was more long deep scrapes than curls..... as you say practice would resolve much of it. Its a skill to develop when time permits and I have a decent chunk of CI scraped ready to play with.
I got offered an aged Biax flaker for £450 - £500 including a new unused blade. I had to walk away as I just dont have the funds to invest in it - pretty sure I will kick myself in the near future about that but thats how things go. Right now Im keen to get the machine back together and see it cycle and then start making some chips. ... I might even allow myself a little time to think about the next project !

For the " push and twist " technique to work effectively your scraper must be kept really sharp. I used a " Sandvik " carbide scraper for most jobs. Some people don't rate them but I'd no complaints. Just as long as you have a diamond lap to keep the edge nice and keen.

Regards Tyrone.
 
Here in the US, you'll see 5 power flakers for sale for every scraper on eBay. The flakers usually go for less than a scraper too.
 








 
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