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[Newbie] My First Attempt At Scraping
- Thread starter Standingbear
- Start date
- Joined
- Jun 15, 2013
- Messages
- 1,199
Ken, thanks for the comments, but no I didn't rub so much that it rub the ink off the high spots, first I rub on the inkd area of the plate, then I place the part over an area of the plate that has no ink and rub it, which does like you say remove the ink from the highest points. the recommended time of rubbing of 20-30 seconds is really more for beginners, however now that I have progressed, I find that like you mentioned around 6 nice steady slow strokes is really all that it takes as long as you have the right amount of ink on the plate, and there is only one way to find out, it takes practice to get it all right. im still very much a novice, but I have had some very good instruction, I don't wanna take away from hobby machinist, I feel as tho its my home, but when it came to asking and learning about scraping, I went to PM to talk to Rich K, and to guys that scrape for a living.
I have spent countless hours scraping at the hobby level, like many of us here, we were lured to the finish, and then like a disease it takes over, and your scraping everything, making scrapers, making pull scrapers, and wow what a finish that pull scraper leaves. The most important thing I have learned so far about scraping has to do with reading the ink, that has got to be second to none, it determines if you are correcting geometry or if you are ruining it.
I have spent countless hours scraping at the hobby level, like many of us here, we were lured to the finish, and then like a disease it takes over, and your scraping everything, making scrapers, making pull scrapers, and wow what a finish that pull scraper leaves. The most important thing I have learned so far about scraping has to do with reading the ink, that has got to be second to none, it determines if you are correcting geometry or if you are ruining it.
- Joined
- Mar 3, 2014
- Messages
- 634
Really enjoy the discussion and photos here. Am learning from the guiding comments and finding that my experiences and amateur conclusions are much the same as others.
Am currently remodeling the interior of my house so scraping, and many other projects, will have to wait awhile, but threads like this help a lot to keep
my head in the game.
Yea, I wanna scrape everything now.
Am currently remodeling the interior of my house so scraping, and many other projects, will have to wait awhile, but threads like this help a lot to keep
my head in the game.
Yea, I wanna scrape everything now.
- Joined
- Mar 24, 2016
- Messages
- 41
You are right about it being an addiction. I find myself thinking about scraping dots. It also seems to be a good relaxing before bed time. Only problem is sometimes I lose track of time and get to bed way to late. You talked about the pull scrapers, I have seen u tube videos and it seem much more controled. It is probably just the person but does look good.
Bench is almost done so I can get back to scraping. Also I picked up some artist oils I am going to try this weekend. Thanks for the tips!
Also glad to hear others are getting useful tips out of this too.
- Joined
- Jun 15, 2013
- Messages
- 1,199
Mix the oil paint with equal part vaseline to keep it from drying.
The pull scraper you can't get the same ppi, you can flatten a surface but your ppi is low with a high pop (percentage of points) so you flatten with the pull then point it out with a push scraper, pull scrapers are flat with no radius
The pull scraper you can't get the same ppi, you can flatten a surface but your ppi is low with a high pop (percentage of points) so you flatten with the pull then point it out with a push scraper, pull scrapers are flat with no radius
- Joined
- Mar 3, 2014
- Messages
- 634
I found that if the pull scraper is really sharp and true it will scrape a lot of metal with each stroke but not as good as a push scraper and it must be sharpened more often.
The spots I get with a pull scraper are much larger and the blue has to be very very thin to get a true reading.
The final surface is more like a mirror than I can get with a push scraper.
This is of a china cast angle plate which is very porous and has some inclusions. With good cast iron its hard to see the scrape marks.
The spots I get with a pull scraper are much larger and the blue has to be very very thin to get a true reading.
The final surface is more like a mirror than I can get with a push scraper.
This is of a china cast angle plate which is very porous and has some inclusions. With good cast iron its hard to see the scrape marks.
- Joined
- Jan 16, 2020
- Messages
- 8
Van Son Holland Ink Corporation, Islandia, NY. http://www.vansonink.com/products/Rubber-Base-Plus.html
Rubber based inks do not dry on the surface plate, thus the advantage to using them over other inks. The bad part is that the smallest quantity you can purchase is one pound, which runs right around $30 depending on specific color. But that one pound will last you a lifetime!
- Joined
- Mar 3, 2014
- Messages
- 634
These pics are of the straight edge I scraped and used the pull scraper for the final finish. Lots of errors but the indicator , 0.0001" grads, showed such a small flutter running over the surface that I know the errors are only a small fraction of a tenth.
One to show pattern and the other to show reflection. Its seen a bit of use and shows some scratches n wear.
Both pics are of the same surface. I just tilted it to get the best shots.
Is it better to use a push scraper for a flat reference surface to help it carry the blue?
