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First scraping project

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Liljoebrshooter

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I wanted to start a thread about my first scraping project.
I got the idea a couple months ago after reading about hand scraping and thinking about the cross slide on my lathe. It definitely has a little wear and gets tight near the endof its travel. Well there is only one way to fix it correctly, scrape it back into proper alignment.
After doing a lot of reading and checking out tools, i started ordering supplies.
I bought the die spotting ink that is recommended by people on the other board. The big decision was finding a granite surface plate at a reasonable price. I ended up getting a 12"×18". It was pretty cheap and the next size up was quite a bit more. It didn't take long to figure out it needs to be bigger. Oh well ya gotta start somewhere.
I bought a Sandvik scraper and found another carbide insert so I could grind the common radius needed.
The grinder and lap was something I thought about for awhile. I had a variable speed motor off a wood lathe sitting on the shelf that will work ok. I turned an arbor to hold a diamond lapping disk from e bay. It works ok but has a lot of runout.
I bought a rough casting for a straight edge from Gary Martin. They are priced good for a first time peoject.
I milled it flat and started scraping.
It didn't take long to realize it is more difficult than it looks. I started before I had a very fine wheel to lap the insert with. You can see it in the finish of the scrape marks.
Here are some pics of the straight edge as I was working on it.
Joe Hynes 290164290165290166
 

Liljoebrshooter

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More progress.
The last pic is where I finished at today. I will probably have to touch up the dovetail again. I think it moved a little bit after working on the bottom so.e more.
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Liljoebrshooter

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One thing I'm having trouble with is getting the right amount of ink on the plate. It is only about 58 degrees in my shop and it doesn't want to transfer with a really light amount.
Maybe someday it's gonna start warming up.
 

Bob Korves

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The bottom surface in the last photo looks good from what I can see of it. Do you know how to do the hinge test and do it for each blueing? The dovetail angle surface does not have enough points yet for precision scraping work, from what I can see in the photo. And yes, every time you adjust one surface, it affects the other surface. The ink on the parts looks OK to me, correct thickness and transparency. The first photo looks pretty crummy, like mine did for quite a while before I got the concepts down. Your results in the successive photos show you are now getting the idea. Congratulations, it is not easy to scrape in a dovetail straightedge!
 

benmychree

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So far as scraping one surface effecting the others; study up on "ringing" the straightedge, you hang it up and take a soft hammer and lightly strike it repeatedly, it acts to stress relive the stresses induced by scraping, I have seen it in action on my own projects, it really does work.
 

popeye

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your stroke length can be a bite longer when stating out on something, but you will want to shorten up on the stroke as progress dictates. I always applied my dykem ( HI Spot ) with a small paint brush say 1''1\2 wide and not a cheap brush I might add it will need to be of higher quality . Thicker dykem can also be used at the beginning , but must be thinned down as progress is made. you will need to make a jig up to test all four surfaces at one time. I am someone whom has many years of service in scraping and aligning. I was taught by a friend from England and worked with him for several years. If I can help you in anyway I would be glad to help.
 

Liljoebrshooter

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Well I haven't touched the straight edge this week, I decided to start another project. I just bought this angle plate and was curious how flat it was. No surprise it wasn't very flat, well it could be better anyway.
Here are some pictures of the progress. I started on the bottom first. It was high on opposite corners.
This was different to scrape since it is so narrow. Makes you pay closer attention to the edges.
After getting the bottom in better shape I started on the top today.
I knew this was going to be a lot more work than the bottom. After bluing the top and flipping it over I then saw how much it was going to take.
Here are some pictures of the progress.
I will give people who scrape for a living a lot of credit. It is a LOT of work. And these are small jobs I'm doing.290487290488290489
 

Richard King 2

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Looks pretty good and as I always say "practice makes perfect" As you scrape more you will discover you need to put a pad on the end of the handle and body scrape and just not arm scrape, witch will wear you out. As Ben suggests you need to hinge or pivot the parts and a last table is high in the middle or the 2 middle sections are higher then the outside ones. set your straight-edge on it and I bet it sill spin or pivot in the middle. Also you will get a huge education by watching you tube: Stefan G in Germany, Tom Lipton of CA, Keith Rucker in Georgia, John Sanders in Ohio....all students of mine. If any of you want to ask questions to a Professional machine rebuilder and scraper who has been teaching people to scrape all around the world for 40 + years please check put my forum at the head of the lists.

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Liljoebrshooter

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Thanks for your reply Richard. I have been reading a lot of threads on here and PM and watching vidson u tube.
This is something I have been reading about for quite a while and finally decided to get the stuff needed and give it a try.
Eventually I want to scrape my compound and cross slide on my lathe. I just wanted to practice on these small, simple flat parts to start with.
I have been hinging the parts on every blue up. The angle plate table is just inside the ends right in the middle, just where the blue is showing. This top gets heavy flipping it around. I think it weighs about 50 lbs.
I would love to take one of your classes but it will probably never happen.
Thanks again for the help guys.
Joe Hynes
 

Liljoebrshooter

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Oh, I forgot to say I'm not done with the table. That's where I left off the other night.
I had visions of scraping my mill when I got this idea to begin with, but I can see how big of a project that would be.
Joe Hynes 290606
 

Richard King 2

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Wipe off the blue the plate and SE and set it in several spots on your plate and hinge it. That will show you how good your plate is. Once you find a few spots that hinge the same way, then you have found a pretty flat spot. (s) Then next time you blue up on you ink, pick it straight up and set it down on an area you did not blue up. and rub it say to a count of 15 and that way the smeared thick blue gets shinny of the highest blue. If your shop is 56 degree's you need to do it this way as inks are designed to be used at 68 degree's. I apprenticed under a employee of my Dad's who only shinned parts and not bluing. He would rub red-lead on the part to dull the finish. Biax / Dapra tells the readers of their booklets to use rubbing alcohol to leave a dull film on the part and then rub it on a clean plate and you scrape the highest spots that get shinny . As someone else said, you are scraping to long with a to small of radius blade. Next time you sharpen your Sanvik insert grind all 4 sides. one a 5" radius, one side a 4" circle, one side a 3" circle, then a 2" circle.
 

popeye

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I looked at a picture of someone choking up on a hand scraper and scraping in his straight edge in a vise. Please just place your straight edge in a simple jig to hold it while you utilize your entire length of your scraper. IF you choose to lengthen your handle that is acceptable .Cut a baseball bate in about a 3rd length and place the body of your scraper in the end.(handle end) scraping can be done much simpler by using your hole body swinging in a rhythm. I am not trying to scrutinize any others opinions please. Improper technique will result in bodily injury. I have had two shoulder surgery's and carpal tunnel surgery in both wrist. As I stated before I have many years in this trade. I am not hear to compare with others, I am 58 and retired, although it is a strenuous job it has been very good to me and my family.
 

Richard King 2

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I have taught over 30 thousand people my method of body pushing the hand scraper plus I teach people to use the BIAX power scraper and have never had any surgeries due to my job. I started scraping in the basement of my parents house around 1962. I was 12. I have been a journeyman Machine Rebuilder& Millwright for 46 years. I am 68. I am not retired yet, but have been talking about it for 4 years.

I have had aches and pains from scraping, but many do. I recommend people buy or make a Swiss design scraper that Biax Germany sells in the states though DAPRA. I call it the professional model. My first scraper was a file with a ground tip, then an Anderson HSS and then a Carbide tipped Anderson, then a carbide insert tip Sanvik then around 1984 I started to use the Biax type loaded with a 1" wide x 6" long carbide tipped blade sold by Biax Swiss type , If anyone wants a copy of the blue print Message me with your email and I will send it to you. The BIAX style also allows youto use a carbide insert too. https://www.dapra.com/biax/scrapers/accessories.htm I also sell the Connelly book shown in the link and if you look at the scraper page you can see where DAPRA advertises my classes too.
 
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