[NewHobby]

Man leveling is hard. Take one side down then the other is higher, Take that side down then the other side is higher. If anyone has any insights to help me it would be appreciated...

:banana:

[dertsap]

Where theres a spark theres about to be a flame(flame2) . Just kidding , but expect the worst because guys can get a bit weird about these things .
I'm just curious , was your x2 that far out of whack . Also are you trying to grind things into a proper fit / flatness /parallelism ?
They aren't the most rigid machines , or designed to be all that precise . But without modifications they can hold their own if properly adjusted , I can run 3d stuff and create locating pin holes all day long with both of mine and they are pretty much dead nuts to where they should be every time .

[NewHobby]

Ha ha yep, I look forward to all kinds of remarks. Leveling with a grinder ha!

Actually that is my spare practice table. I have 2 and 2 bases to boot. Used one set to practice on.
On this table I got one side dead 0 across x with .0005 indicator but the other side had one corner that stayed .003 high the last 2 inches of x. All 0 or close to it then sudden rise up last 2 inches. Frustrating as hell. I took down so much chasing it the 2 sides got out of level and I would have to take it all down even more so I decided to just use that table to do cause and effect analysis with different levels of metal removed. The end that was sticking up the. Last 2 inches is not what was making it high. Funny because sometimes where you think it is high is actually somewhere else when scraping a table flat. A grinder made learning and seeing effects much faster, besides my scrapers got dull. Waiting for new German ones now actually. It can be flat but still have a high corner etc... Angle grinding just to validate a few things was interesting and worthwhile. I thought it would make a funny post since some guys are rigid in views. Just mention lapping gibs and fists break out ha ha.

The sx2 mill was pretty good out of the box for general work but I am looking for .0005 or better across the table and seek to eliminate any column flex or twist while raising it up 2". The mill if fine for aluminum and shallow steel cuts, column is more stout than the regular x2 for sure.I figured I'd brace it just to do it as well. There is no such thing as too heavy or too much bracing/reinforcement with a mill.

The more you take it down the more pronounced the gib effects are too. No one told me that. I will need new gibs made before I go further, waiting for material. Oil infused brass is more expensive than one thinks, oh well it is the right stuff regardless of mill brand type or model in my mind.

[bjones]

Actually that is my spare practice table. ...besides my scrapers got dull. Waiting for new German ones now actually.

I decided to order another table and use the current one to practice some random techniques to see thier cause and effect.

so in truth this is the one you ruined first and now it's a spare to make a silly picture. did you think to try and resharpen the scrapers? could use your angle grinder just asking.

[DareBee]

Feel free to do whatever you like.

The purpose of scraping is to add imperfections to the surface. These allow oil to have places to pool so that the ways have an even film of oil for proper operation.
Both sets of ways are typically precision ground or milled perfectly true first.
Of course, before all that, the parts need to be stress relieved. The fixture that hold them in the machine must also not induce stresses.

This is why machine tools cost as much as they do

[NewHobby]

so in truth this is the one you ruined first and now it's a spare to make a silly picture. did you think to try and resharpen the scrapers? could use your angle grinder just asking.

Ha ha go stress relieve your imaginary mill so you don't have to throw money you don't have at it lol!

[NewHobby]

Yes dare eye, i actually I got it overly smooth as well, good point, the first table was to practice with, actually it was better than it was when new but not good enough for me, scraping it level without making it smooth is not as easy as it sounds. I figured it may be that way so I bought 2 of each up front as it is inexpensive to do so with this particular mill, practicing on the actual parts is better than scraping random metal I figured. I have to say it is not as easy as it seems.

[COMachineist]

Hi NewHobby
The first thing you should do is before you touch the casting with a scraper is to have it stress relieved, then machined to close spec. Next you should not scrape dovetails with out a dovetail straight edge for marking. You will also need a flat straight edge for the ways, and a surface plate to get things flat and rubbing the marking dye on. Never grind on a machine casting, the grinding wheel heats the ground spot and cause all kinds strange things to happen and move. Scraping is not for oil retention, it is to get everything flat, parallel and straight. Flaking is to add little half moon scratches to retain lube which does nothing to get things flat, parallel and straight, it does looks cool. Other wise you are wasting your time and machine parts. You will need a diamond slow wet grinder like a Glendo Accu-Finsh to sharpen scraper carbide, other wise the scraper edge will be chipped and cause sever scratching which is a no no, smooth, sharp scraper edges are a must to do the job right. You can use files but they dull really fast and you'll spend a lot of time sharpening.
Good luck
CH

[dertsap]

is there any chance that the one end of the table is lifting as the table extends further out from the base ? If the gibs allow for any play then it's possible for it to teeter . Have you tried dialing and jiggling the table at certain points to be sure that there is no slop .

[Khalid]

It is grinding not scraping.. Scraping is a skill and especially hand scrapping is a tedious and patience job...

[neilw20]

Once I actually purchased a small surface grinder, the gibs were then acceptable.
Without that precision, it is like chasing rainbows. Just keep it well oiled. If it gets a bit dry, then I lose steps. Means it needs oiling again!!!
My SX3 gets the gibs reground every 150 hours or so, and skim maybe 1 or 2 thou off them. It took about 1000 hours to bed in nicely.
My Z machining is to microns, believe it or not, so ANY rock or wobble or teeter just destroys things.
Without the surface grinder, I could never get the gibs tight enough without sticking spots.
I run reduced max feed rates and live happily with a very stiff machine.

My Z column is attached to a brick wall. Without that, my microns would be multiples of thous.
I allow spindle to warm up for 45 minutes, else, it is back to thous.
If you can extend the table, and grab it firmly, back and forwards, and get more than a thou at the end, then things are still not parallel (enough)
When mine is setup nicely, I can't feel ANY movement, doing the push pull thing.

I spent all of one day scraping and getting the Y slide on the base of machine parallel. Damn base had a tiny warp.
Yes, they machined green castings, no doubt, and probably still warm!!

Yes, I have head nod, as is inherent in the design, and have about 35 microns of head nod I compensate for in program.
Down to position, and another 35 microns down past the program point (the nose is still lagging and is still high), then move up 35 microns, and the nose, just changes directions to position.
Head nod is another story, all on it's own. If head nod is not compensated for, on the finish cut, then when tool retracts, it digs a slight hole.

[Gregj888]

NewHobby, taking a grinder to the ways looks just wrong... I agree with COMachineist... and am also new to scraping. I've scraped most of my HF MiniMill using classical methods. I marked the saddle using a granite surface plate, then used the saddle to mark the X table ensuring the two ways came to the same plane. I also marked the X table ways directly against the plate on occasion to make sure the long axis stayed true.

Not quite done, but a test indicator on the the X axis set to 0.000 in the center is +0.0015" at each end. That's in Z, the front edge is about the same (wiggle in X). Neither surface is flat, so hoping once that's taken care of, I'll be well withing the 0.001" I'm looking for. Still need to do the dove tails, but need a gauge, per CH.

I made the first cuts a few days ago, project couldn't wait. Cuts have a nice finish, so all is OK so far. Have the ballscrews, controllers etc to CNC once I get the base mill cleaned up.