- Joined
- Mar 3, 2014
- Messages
- 634
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, 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.
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.
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, 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.
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.