Do some work, finally:

You mention low quality and high quality cobalt drills. I buy nothing but cobalt but I didn't know there were grades.
What is/are the highest quality (hardest) cobalts out there and where do you get them? Quite frankly, I thought cobalt was cobalt.

BTW, I bought a Drillmaster a long time ago. What a POS.
 
You mention low quality and high quality cobalt drills. I buy nothing but cobalt but I didn't know there were grades.
What is/are the highest quality (hardest) cobalts out there and where do you get them? Quite frankly, I thought cobalt was cobalt.

BTW, I bought a Drillmaster a long time ago. What a POS.



The difference would be the amount of cobalt.
This will explain it better than I ever would be able too. Although this is a comparison between cobalt and Titanium, you can get the idea. I'll see if I can find a better explanation.
http://www.ehow.com/about_5549247_cobalt-vs-titanium-drill-bits.html

http://www.ebay.com/sch/i.html?_trk...&_nkw=cobalt+drill+bit+set&_sacat=0&_from=R40
 
Drill burning up is typically one of two things. Either your RPM is to fast, or the drill is just very cheap low cobalt. Automotive sheet metal is very soft, although the weld may be a bit harder, but there is no reason to go through a lot of drills. Get yourself a good quality cobalt drill, and keep the RPM down. The chips should not be turning colors. A small amount of cutting oil may help also. Here is a pic of the one I made. It's a little rough because my bench grinder is not mounted solid. It's on a pedestal and it vibrates and moves while I grind. The important area is that the pilot is slightly longer than the cutting flutes so that it centers itself and have proper relief so that it cuts rather than rubs.
View attachment 27068

I used to make those back in my tool & diemaker days. I never got around to making myself a set of them..
 
BTW, I bought a Drillmaster a long time ago. What a POS.

All those drill "sharpening" machines really don't do the job. Give me 15 minutes with anybody with decent coordination that's used a bench grinder before and I can have them sharpening drills by hand.
 
Thanks all. I drill sheet metal in airplane parts for 16 years and haven't used one of the pointed bits. I can borrow any type of drills at work, HSS, cobalt and of course carbide drills. I liked the video.
 
You can dissemble half a body with one good drill if you keep rpm low, don't bore further than necessary. I center punch as well and even use a drop of oil for cooling. I think I used up about five in 25 years all still saved during apprenticeship in a body shop around 1989-91
 
Yeehaw, I got the quarter off. Now what to do. I was going to use the inner wheel housing as well, but it is rusted. I will just cut pieces to fix my car. I'm tired. parts car 045.jpgparts car 046.jpg

parts car 045.jpg


parts car 046.jpg
 
I wire wheeled the rust on the back of the quarter. I sprayed on some rust encapsolator, I will be replacing with good metal, I just wanted to make it stiffer.parts car 049.jpgparts car 050.jpgparts car 051.jpg

parts car 049.jpg


parts car 050.jpg


parts car 051.jpg
 
"Sweet dreams, and flying machines, and pieces on the ground."

:eek:ccasion14:
 
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Wow,you make it look so easy!Just a few drill holes and wah-la,instant quarter panel.Save as much good sheetmetal as you can,even if it's just to cut up for patching sections.There's a large expanse of good sheetmetal on that roof alone,all in the right gauge to match the rest of the body.Nice job!
 
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