Just bent a drill bit

[forgeblast]

I see so many bits with so many different coatings. It gets a bit confusing. I want a set that I can really use. My old bits are just that getting old and I am missing some sizes. I need to up grade and need to figure out which ones I want to spend money on.

 

[Bird]

We love roundabouts, some are called Islands

Paint and body shops ought to love them, too, because they generate so much business for them.:laughing: Many years ago, before they finally did away with it, I got to work some interesting wrecks at the one on Harry Hines Blvd. at Northwest Hwy. in Dallas.

 

[Short Game]

The roundabout they put in on U.S. 101 in Astoria, OR, is the best thing ever. It used to be the longest traffic light and it would back the traffic up so far that it would take several cycles to get through, and a left turn was nearly impossible during the touring season. Now, if they'd just stop raising that drawbridge 1/4 mile south of there....

 

[k0ua]

Here in Branson, we are right up town, we have both a Roundabout, and a Diverging Diamond Intersection.!

James K0UA

 

[crazyal]

We have a big push around here to switch from lights to roundabouts. Of course they have no idea how to build them or don't want to spend the money to build them the correct size. The latest one they put in is about 1/4 the minimum diameter it really needs to be. Being so small means that only a handful of cars can be in it at one time with very little room to merge in between the cars.

 

[Sutol]

We have mini roundabouts here as well, they are just a small mound of tarmac in the middle painted white, I just drive over them in the Land Rover

Roundabouts are safe as long as every one sticks to the rules. give way to traffic which is already on the rounabout...simples

 

[NormL]

We have a big push around here to switch from lights to roundabouts. Of course they have no idea how to build them or don't want to spend the money to build them the correct size. The latest one they put in is about 1/4 the minimum diameter it really needs to be. Being so small means that only a handful of cars can be in it at one time with very little room to merge in between the cars.

Now - introduce a fortyfive foot bus and you see why i despise 'em

 

[Scooby074]

Thats some peanut-buttery drill bit. Never seen a (good) bit do that.

You said its made in the UK? PLEASE tell me its not a Clarkson-Osbourne. Thats my usual brand (or Dormer). Id hate to think quality was slipping.

 

[Sutol]

Thats some peanut-buttery drill bit. Never seen a (good) bit do that.

You said its made in the UK? PLEASE tell me its not a Clarkson-Osbourne. Thats my usual brand (or Dormer). Id hate to think quality was slipping.

Thing is that the bit did drill into a hardened steel ball bearing when other bits wouldn't even scratch the surface.

I'm thinking that only the tip of the bit was hardened or coated with whatever.

My fault it broke though, if I had followed the rules and clamped the ball before drilling then maybe the tip wouldn't have snapped off the bit and jammed the drill in the ball which then began to spin out of true till it bent the bit. The ball was very heavy.
did the job though:thumbsup:

 

[Craig Clayton]

To Sutol
I spotted that first off when you mentioned the carbide insert. I use drills similiar to yours to drill into concrete. A slang in the trade is it is called a Carboly. That describes a drill with a soft steel shank with a rough turned spiral flute and on the end is silver soldered a solid carbide insert. The carbide insert is ground for a percussion point that is why the drill is placed in hammer and drill at the same time. These drills come in 1/4", 3/8"
, 1/2" shank, the larger ones are SDS ( splined drill shank ) and SDS MAX.
Now there is a trick and that is to resharpen the percussion point to a twist drill profile. This can only be done on a GREEN STONE wheel , these are the only wheels that can touch carbide.
It is possible to have a twist drill point with a carbide insert but I have not seen them .
A fellow at the plant did order a solid carbide drill to remove a very tough bolt and it was costly and it looked like a regular twist drill except it was black and looked expensive.

Look at all the fun we are have drilling a hole in a ball bearing.

Craig Clayton

 

[Sutol]

To Sutol
I spotted that first off when you mentioned the carbide insert. I use drills similiar to yours to drill into concrete. A slang in the trade is it is called a Carboly. That describes a drill with a soft steel shank with a rough turned spiral flute and on the end is silver soldered a solid carbide insert. The carbide insert is ground for a percussion point that is why the drill is placed in hammer and drill at the same time. These drills come in 1/4", 3/8"
, 1/2" shank, the larger ones are SDS ( splined drill shank ) and SDS MAX.
Now there is a trick and that is to resharpen the percussion point to a twist drill profile. This can only be done on a GREEN STONE wheel , these are the only wheels that can touch carbide.
It is possible to have a twist drill point with a carbide insert but I have not seen them .
A fellow at the plant did order a solid carbide drill to remove a very tough bolt and it was costly and it looked like a regular twist drill except it was black and looked expensive.

Look at all the fun we are have drilling a hole in a ball bearing.

Craig Clayton

Well you're right of course and I haven't had to sharpen any of mine yet and that is the first one I have had any trouble with.

Here is the finished trophy for my friend who wrote his car off on a wet roundabout.
You can see the size of the ballbearing in this pic, I drilled into it just over an inch and it isn't just case hardened steel it is stainless steel (not magnetic and very hard)
The bit on top is a piece of his wheel that was picked up off the road, we are to present it to him tomorrow together with a photo of him alongside his wrecked pride and joy with his head in his hands:laughing:

All in good fun and he will treasure the trophy I'm sure.


Serves him write for not buying a Lotus, he went for the cheaper Vauxhall alternative

(you may have noticed that Sutol is Lotus backwards)

 

[SPYDERLK]

I can only think that the bit was so hot that its shaft was softened allowing it to deform after the hardened cutting edge had snapped off.

Unless anyone has a better explanation:anyone:

Bound to have been a carbide tipped bit.
larry

To Sutol
I spotted that first off when you mentioned the carbide insert. I use drills similiar to yours to drill into concrete. A slang in the trade is it is called a Carboly. That describes a drill with a soft steel shank with a rough turned spiral flute and on the end is silver soldered a solid carbide insert. The carbide insert is ground for a percussion point that is why the drill is placed in hammer and drill at the same time. These drills come in 1/4", 3/8"
, 1/2" shank, the larger ones are SDS ( splined drill shank ) and SDS MAX.
Now there is a trick and that is to resharpen the percussion point to a twist drill profile. This can only be done on a GREEN STONE wheel , these are the only wheels that can touch carbide.
It is possible to have a twist drill point with a carbide insert but I have not seen them .
A fellow at the plant did order a solid carbide drill to remove a very tough bolt and it was costly and it looked like a regular twist drill except it was black and looked expensive.

Look at all the fun we are have drilling a hole in a ball bearing.

Craig Clayton

Diamond sharpens carbide just fine. Green wheels [silicon carbide] would be 2nd choice.
larry