That hurt !

tertiaryjim

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Finally finished, sorta, scraping in my cheapo mill/drill.
Worked on it most days for six weeks which is a ridiculos amount of time but with perhaps the exception of the table top which was out only a little
over two thou. out every other surface was at least four thou. out and most much worse. No two surfaces were parallel, square,IMG_0409.JPGIMG_0404 - Copy.JPG flat or even close to reasonable.
Had to do all of it by hand scraping.
The top pics are of a test bar to check how acuratly it would machine its length. As you can see it required a lot of over-extension of the table to machine this
almost 18" bar. I scaped one side to have a flat surface to rest on and measure from and moved the clamps to keep then within a few inches of the cutting tool.
The last two inches of the bar ( both ends ) showed respectively -.0001" and -0.0002 " sag. I had to stop and sit down in the middle of the bar which allowed the spindle bearings to cool and there was a short area there which was +0.0002".
I attribute the sag to not having the gibs properly scraped. They give me a hard time.
The spindle bearings could be damaged due to all the extra pounding they've taken with the saddle and table dancing around.
IMG_0409.JPGIMG_0404 - Copy.JPGIMG_0402.JPG
This 6" X 12.75" plate was machined on all four edges to check for square and how straight the edges would be.
One corner checked true without any error or it was smaller than I could detect. The opposing corner was out 0.0001" and all edges were flat within 0.0001".
Again, The gibs are hard to do. This picture is of the second time I preformed this test, which it failed. On the third test I set the plate on steel bars to help reduce any clamping errors. The only adjustment I made before the last test was to adjust "scrape" the gibs.
This 6.3" X 12.5" machine now has 6.7" and 19.3" travel. One must be careful when the table is over-extended but that area is usable.
The factory nuts were trashed and new ones constructed which have less than 0.003" backlash. I'm sure they can be better adjusted.
Besides the extra "reach", better finish, and incredibly improved acuracy, tooling should last longer without the saddle and table pretending to be at a rodeo.
Am fitting covers for the ways and considering a DRO.
 
Congrats on getting that cool project done. It's amazing at what can be accomplished by hand.
 
Excellent work! Go for the DRO, you'll never regret it.
 
Thank you all for the likes and kind words. It's a good feeling to finish a project.
Those pesky gibs and the flaking were hard. Got the gibs in close but don't think I'll ever learn to do good flaking except on a nice easy to reach
surface. Hands and wrists just don't like it.
Created some digs and scratches but just couldn't see re-scraping the whole surface/surfaces. Just stoned them and continued.
Thats a nasty thing to say but I'm about outta ump.
Also flaked the lathe cross-slide and compound. I had put oil grooves in all dovetails of both machines .
Got a few nice flake patterns but wherever it was out of position, well, I don't really think you could call it flaking but it will hold oil.

Noticed that I said the edges were within one tent but I have realized that I didn't run a indicator over them and only checked/compared the top and bottom of the four edges. They could belly out and have caused measuring errors. Will check on that.
Been reading other posts about dro's. Might spring to do the lathe and mill with glass scales.
Its really great to have rigid machine components. Parting on the lathe is now fast and easy.

Now I gotta make a few tools so I can make tools to complete the tool grinder, shaper, and some other tools so I can just maybe
get to the projects I would like to do but can't even remember cause I'm working on so many machines and tools needed to do all those other
projects.
If any of that makes sense to you, I offer my condolence.
Also, I will be relying on you for ideas and information to build some tools............................................
 
Makes perfect sense to me, and I'm sure to many others here. Nice work. Mike
 
You scraped 4 thou out of true?!? Wow! You've been busy! Hats off to your perseverance. Was this your first experience? Do you see a difference in the cytting performance i.e. les chatter? Also, if you had to do it again, would it take just as long because of all the material you had to remove or would the learning curve make it quicker? Thanks for posting.
 
Most of the surfaces were out more than 0.004". Cheap china machine.
I had scraped in a 13-36 lathe and done work on my grinder as well as some work on a 7" shaper before I started on the mill.
It had no rigidity and even with the gibbs really tight it vibrated and shook at both top and bottom dovetails.
The table travel described an arc and didn't follow a straight line.
There is now a "great" increase in rigidity and it will machine square corners as well as flat surfaces.
Finnish has improved and I'm sure cutting tools will last longer.
With the experience I already had there was still a learning curve. I could do it faster now but with arthritis my hands and wrists don't like scraping.
I have a problem keeping the tool angle and getting good depth. Much of my scraping is shallow or flatter than ideal.
Still, it is flat and square and so much better than the machine was produced with and the travel is nice throughout it's range.
With the lathe and mill both preforming so much better , I can use them to machine surfaces of the shaper and power hacksaw and build indicator jigs to better measure my work as well as tools to help finish my grinder.
 
The Chinese mfgs don't season their castings by heat treating or just letting them age. They cast them and machine them and that's it. Then a year later you get your machine and it is made up of banana shaped parts. I hope they have stabilized and it stays true. That was a herculean effort to be sure.
 
Impressive. I'd like to hear a little bit about the tools you used for this project.
 
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