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+--- Thread: mini mill (/thread-601.html)
RE: mini mill - NevadaBlue - 07-24-2012
I use Adobe Acrobat (an older version) and I've noticed that it wants to put the computer user's name in the Author space. I didn't know this originally but now I try very hard to edit those fields to include the REAL author, title and the website where the document originates.
RE: mini mill - Mayhem - 07-24-2012
(07-24-2012, 07:00 PM)NevadaBlue Wrote: I use Adobe Acrobat (an older version) and I've noticed that it wants to put the computer user's name in the Author space. I didn't know this originally but now I try very hard to edit those fields to include the REAL author, title and the website where the document originates.
Depending on the version, Acrobat should allow you to add a header and footer to the document. I would advocate putting the author's name, the website name and also the url of the original post in the footer. Not only does it correctly reference the author, it points people back here. After all, the PDF will end up all over the web and this just points them back here.
RE: mini mill - Highpower - 07-25-2012
(07-24-2012, 07:17 PM)Mayhem Wrote:(07-24-2012, 07:00 PM)NevadaBlue Wrote: I use Adobe Acrobat (an older version) and I've noticed that it wants to put the computer user's name in the Author space. I didn't know this originally but now I try very hard to edit those fields to include the REAL author, title and the website where the document originates.
Depending on the version, Acrobat should allow you to add a header and footer to the document. I would advocate putting the author's name, the website name and also the url of the original post in the footer. Not only does it correctly reference the author, it points people back here. After all, the PDF will end up all over the web and this just points them back here.
Did I just hear someone volunteer to do a "how to" on performing this procedure with Acrobat?
RE: mini mill - dallen - 07-25-2012
I pretty much finished the scrapping last night on the last part which was the joint between the part that the column mounts onto that is bolted to the base. I got tired of using the narrow scrappers I had been using and grabbed one of the old files that I have laying around and started grinding on it (not exactly like the sketch that Rick posted) and actually got it to cut. this helped out by removing a lot of material from some spots that needed it.
Anyway this morning I put the mill back together at least far enough that I could turn it on, and believe me its like having a whole new machine, the table does not try to jump and jerk and I don't have to ride the locks. the table action is smooth (had already put in Precision Acme Lead Screws) with out all the slop that it did have.
The next item on the list if to align the head so it will cut flat then see what kind of a finish I can get. I know that I still have some more work to do to it. #1 is the column as I didn't scrap it after recutting the dove tail way and the finish that is one the column isn't the greatest.
I still have a long way to go before I can say that I know how to scrap but at least I can say I have started learning, now if I could only find someone in my area that knows how and would be willing to show me the right way cause I have a really bad feeling that what I am doing is the wrong way.
Also received yesterday some water base spotting dye, stuff seems to work ok with out drying out and is somewhat easier to clean up.
RE: mini mill - Highpower - 07-25-2012
DA, what are you using to spread your dye with? Roller or dauber?
I'd like to hear what you think about the water based stuff after you've used it awhile. I've been sitting on the fence about trying it.
I would love to be able to find a local scraping class here as well, but I don't believe anyone exists around here to put one on.
It sounds like you are making excellent progress on your mill. Don't get it too perfect, or you won't want to ruin it by using it.
RE: mini mill - dallen - 07-25-2012
I got the water base stuff from an outfit called nemic http://www.nemic.net/ their out of Grand Rapids, fast service and the 8 oz bottle was only like 10 bucks.
I'm using a roller but have used a lint free rag with some of the oil based Prussian Blue pigment that I started with. will give an update on the stuff a little later so far I like it. Spreads good gives good spots and is easy to clean up with surface plate cleaner.
I don't think that I will get it so prefect that I'll be afraid to use it. heck I'm fixing to start trying to hang some stepper motors on it cause I hate cranking on handles to move the table from one extreme to the other, or those more boring repetitious facing cuts one a wide piece of flat bar.
But I do like it a hell of a lot better now then I did 6 months ago, it had so much slop in it, it was useless almost only thing it was good for was drilling holes.
RE: mini mill - Rickabilly - 07-25-2012
Hll Al,
DA the truth is that the only real way to learn to scrape is to spend time scraping, for the highest precision use a very thin film of dye, I have always used oil based prussian blue and I often set up a lamp on the far side of the job just an inch or two above the face to be scraped with the bulb well sheilded so that I can't see the bulb, this way you don't need to see the difference in colour on the high points, rather you see the difference between the shine off of clean metal and the "oily blue film" from the prussian blue, this lets you get the film thickness really thin and thin = accurate.
Then simply take off the high points and retest on the surface plate,
And one minute of scraping after four minutes spent sharpening the scraper will yeild much better results than five minutes pushing a blunt scraper.
The real skill comes in when creating a master plate, that is using three machined plates and scraping them against each other as references in order to create three properly flat scraped surfaces. I did this once during training and that was enough.
From memory I think it goes a bit like this;
1. scrape plate 1 against machined surface, to 80% or better contact,
2, scrape plate 2 against machined surface, to 80% or better contact,
3, scrape plate 1 against plate 2 to 80% or better contact,
4, scrape the original machined surface against plate 1, to 80% or better contact creating plate 3 which should be the flatest most "True" master surface out of the three plates.
Then keep plate 3 as your master whenever you need to scrape a joint or flat surface of any kind, keep in mind when we did this exercise we started with three sand cast blocks and we were not allowed any machine tools so we had to cross cut with narrow chisels finish with cold chisels then file flat to within 0.002" and scrape from there, our "Machined surface" was the best of the filed blocks as judged by the instructor. Pure torture especially considering we did it in a tin shed in January/February in Australia, most days were well over 30 degrees C up to about 42 degrees C so about 90 - 105 degrees F.
There is little need for this sort of work nowadays, given the accuracy of modern grinding machines.
Best Regards
Rick
RE: mini mill - Highpower - 07-25-2012
(07-25-2012, 02:35 PM)Rickabilly Wrote: There is little need for this sort of work nowadays, given the accuracy of modern grinding machines.
Best Regards
Rick
Rick, given that I don't own a grinding machine (modern or otherwise).....
Oh.... there is a need all right.
RE: mini mill - EdK - 07-25-2012
This must be the stuff.
http://www.nemic.net/default.aspx?page=item+detail&itemcode=080-060
Ed
RE: mini mill - dallen - 07-25-2012
I know all that, my problem is I don't have a grinder and since I have been out of work since january I have lots of time to do something like this. I also found out that about the one minute of scrapping and 4 of sharpening. the file that I ground last night cut a lot better today after a few minutes on an oil stone even thou I worked on it last night with a diamond file.
I pretty much stopped on the mill as I don't have anything to actually check the dovetails with, there is an outfit that sells castings of different items and one of them is a Straight Edge I am going to look them up and maybe get one or two just to see if I can do the thing. Be a great casting project for sure.
Anyway the mini mill is in a lot better shape then it was now, and I hope to be able to learn more about scrapping and how to do it, if nothing else just to do the decorative. plus I have three lathes that can use a little scrapping in the cross slides and such, CAC Tool's, well they ain't so cheap just sloppy
Thanks Rick for all the information I downloaded the sketches so that I can save them.
David