Why did you buy this one then? Back to news »
Cast drills for metal (crowns). Here, for example, are photos from work when this crown was used Although she has done a lot of holes. Okay, let’s drop that. They just weren’t for sale. If you don’t go too deep and don’t try to seem too smart, then the crowns are bimetallic, made of high speed steel and with carbide teeth. Large diameter drill, step or conical drill, and core drill (crown). The author is a "krivoruk master" and an amateur. And because there were no others. Here she is Further, in turn, they still differ in the shape of the "bowl" and the presence of spiral grooves for chip removal. They are usually sold without a shank with a central drill. The wall of the device or a metal box (and this is usually 1.5 mm) such a crown passes in a few seconds. But from experience, I can say that crowns with thick teeth of this type cut into metal more aggressively and cut through it faster. I really don’t know what’s the problem with drilling such metal with bimetal bits. And I saw a big muzzle there, not crowns for metal. This is me now about crowns for hand tools. Well, let’s drill, of course… Something may be wrong. Generally. That’s about the crowns and will be discussed in this short review. Well, I have high-speed steel crowns with thick teeth. Not for magnetic drills and machines. Moreover, the height of the cup with teeth in the reviewed crowns is usually 6-8 mm. Without packaging and blisters, it is possible that the local "spill". As I read somewhere, such crowns are positioned for drilling thick sheet metal. I tried and had no problems. Thank you for your understanding. When I bought myself such a crown, before that I had experience of drilling only with bimetallic ones. Thinking about the fact that the country was attacked by a "crown crisis", I went to the state department store, and there I saw crowns that I had never seen before. And not only in this store. I have only one crown from that time. Let’s look at the crown that I bought about 12 years ago, and almost the same one ordered from Ali about a year ago. I initially thought that maybe I was blinded, or they are sold in some other department. Is it worth taking them to Ali?
The crown is also a core drill, and if we are to be completely correct and according to GOST, then the hole drill can be of several types. A large hole in sheet metal can be drilled (drilled, not drilled) in three ways. They will be discussed in the review. I don’t remember the price, I bought it in joy and forgot it, because I was about to fall into despair. With these naive questions, I turned to the nearest store employee. And this item is sold separately. I don’t have any tungsten carbide bits, but I could order them just for fun. But no, it wasn’t blind. The central drill, of course, has already changed more than once (there should be a short one there). I needed a couple of crowns of a certain diameter, and without a second thought I went to the nearest construction hypermarket. Life has not spared the teeth of this crown and in some https://jiji.ng/12-engines/mazda-cx_7 places they are chipped There weren’t any. I have bimetallic crowns at home, I can show them to you The crown cuts perfectly to this day. This means that the thickness of the “thick metal” is limited by this size. They are bimetallic because the material from which they are made is a combination of high speed steel and cobalt. But I must tell you not critical. This crown has a diameter of 30 mm and a tooth thickness of 2.4 mm. And instead of the stock clamping screw for the hexagon, a regular one for a PH screwdriver was screwed in. It was like I said 12 years ago.
Everything that will be written below may contain inaccuracies. Well, at least I don’t know anymore. In this connection, their total cost is quite decent. The crown is all-metal, and only the center drill is removable. They look like this And I drilled a million of such holes, and now in the review I will drill the first million.