MadModder

The Shop => Metal Stuff => Topic started by: PekkaNF on January 12, 2017, 12:58:22 PM

Title: How to scrape near edge?
Post by: PekkaNF on January 12, 2017, 12:58:22 PM

My second attempt on scraping. Failed pre internet times, maybe I have better chance now.

BUT when I'm scraping the edge i can feel scraper crabbing the edge and forming a diagonal burr to it. Is it normal?

I try not to push over the edge. I stop when about 1/4 to 1/2 of blade width is over. My reasoning is that if I push the blade completely over the edge there is a danger of beveling the edge.

I do approach the edge same way than slot or hole: tangentially at 45-60 degree angle.

Much like here:

=196

Question: Is this normal to get more scraping burr near edge or am I doing something wrong?

Pekka

Title: Re: How to scrape near edge?
Post by: NormanV on January 12, 2017, 02:59:40 PM

I can't give you an answer but I have had exactly the same problem so I wait in anticipation for an expert to reply. I am sure that it is in the wrist action!

Title: Re: How to scrape near edge?
Post by: Pete. on January 12, 2017, 04:43:10 PM

It's pure and simple practice. If you're working on a wide part it's not so difficult but narrow edges still cause me a problem. How much flex do you have in your scraper? If it's too rigid you're going to find it a lot more liable to digging in and grabbing.

Title: Re: How to scrape near edge?
Post by: PekkaNF on January 13, 2017, 02:06:45 AM

So far I have two old and well used Sanvik's tyre irons, they do not flex much. Another is a bit shorter and stubby anther is classic file looking 30 mm wide scraper. Got some blades to go and few edges are even fine. Have to buy diamond disc and lap to sharpen them.

http://www.greenwood-tools.co.uk/images/product/full/g_scraper.jpg

I think I'm lacking the right motorics on that part. Also - as Pete said that scraper might be bit too stiff.

Pekka