In the book you'll find numerous tips and info on all aspects of the Gundrilling process. A quick look at the links shows how completely we've covered the subject in the book. We also realize you can spend only a finite amount of time on any one website, and retain only a limited amount of the information you've reviewed.
Accordingly, we created the Gundrilling Handbook, a hard copy reference book which allows us to delve more deeply into all the intricate details of the process, at the same time allowing you to access the information you need on an as-required basis which would be much too time-consuming and thus difficult to achieve over the Internet.
Novice or Gundrilling \"Old-Timer\", the Handbook puts the answers in the palm of your hand, with more than ten times the content of the site. For more info, please view; the table of contents, and the book's forward. If you like what you see, go directly to the Order Page to obtain your copy.
A comprehensive guide on gun drills and gundrilling in traditional and non-traditional applications compiled in a handy 5.5\" x 8.5\" ring bound format to lay flat at the work center or on your desk
A lot has happened in those forty years. Current day CNC capabilities, vastly improved oils & coolants, as well as significant strides in tooling technology make the Gundrilling job easier, allowing capabilities not dreamed of a few decades ago.
But the basics remain the same. The Handbook takes you down both paths, showing what's possible, while tempering your thinking with the basic and fundamental rules of the process. The result is a reference guide which provides all the tools you need to be successful in Gundrilling. It would take several hundred hours to compile all the information presented in the Handbook (we know this from our experience.) Whether you're a 'pro', or just starting to explore the process, the Handbook has all the real world answers you're looking for!
We offer our DM2000 / DM3000 Spraymist Kits as alternative to high pressure coolant.Operate with 100-125 psi of shop air pressure. Spindle speed will be same as Min psi above. Refer to our Speed & Feeds chart or our helpful Gundrilling Guidelines.
The gundrilling process is able to drill deep holes beyond what is possible with conventional machinery and tooling such as twist drills, by using high pressure coolant for clean chip exhaust, even at extreme depths.
Gun drilling was initially developed for the manufacture of gun barrels, where both straightness and barrel durability were essential to properly functioning barrels. The gundrilling process and tooling have been refined for maximum performance and use on modern, dedicated machinery. Firearms continue to be a common application for gundrilling. Other industries include diesel fuel components, medical tooling, plastic injection molds, and more.
Gun drilling can be done, with limited performance, on common CNC machines. Holes with a depth-to-diameter ratio of 20:1 or greater generally require dedicated equipment to achieve the highest productivity and process reliability, and can reach extreme ratios of 400:1 or greater.
The gun drilling process is ideal for smaller hole diameters, up to 50 mm [2.00 in]. The gun drilling process differs from BTA drilling due to coolant entry and chip removal; gundrills introduce coolant internally through a small hole within the tool, and chips are removed by coolant through a groove outside the length of the tool. BTA drilling machines introduce coolant externally, through an assembly around the tool, while chips are evacuated through the drill itself.
Gun drilling is the ideal process for a range of deep hole drilled depths and diameters. Extremely deep holes and small diameter holes utilize gundrilling with specific equipment to maintain straightness and precision.
The drilling head usually has only one cutting edge  and the cutting fluid is supplied to the cutting zone of a channel  within the drill head. To permit long, straight holes the drill is often supported by a control unit  placed near the entrance.
We stock over 600 gun drill sizes and offer quick delivery specials for all your applications on gundrilling equipment and manual or CNC machines. We also sharpen and recondition gun drills of any manufacture.
Gun drill on manual and CNC lathes and mills! Gun drill all types of metals, woods, composites! Optimize performance on gundrilling equipment! Contact Doug Holley with any question regarding your application.
Typically, Gun and BTA Drilling are done on special deep hole drilling machines that are designed for the purpose. Such machines are capable of contra-rotating both the cutting tool (Gun or BTA Drill) and the workpiece, which gives the best results on large depth to diameter ratio holes.
Sometimes even relatively shallow holes (by gun drilling standards) benefit from gun drilling when straightness, diameter, and surface finish requirements are high. The hole size, finish, and straightness of a gun drilled hole are all higher than with twist drilling and other deep hole drilling solutions, so eliminating a second reaming or honing op via gun drilling may save time.
Contra-rotating tool and workpiece contributes to straighter drilled holes. Dedicated deep hole drilling machines also have more sophisticating monitoring of loads and coolant pressures that correctly identify when the tool is dulling and needs to be changed.
We given you some quick information about how to succeed with these deep hole drilling solutions and an idea of what tooling is available. You should understand the basic information needed after going through this content.
Deep hole drilling also differs from normal drilling in that, depending on the drilling process and the drilling diameter, cooling lubricant must be pumped to the cutting edges in large quantities and under high pressure. This ensures good cooling and at the same time good lubrication of the contact areas between the workpiece and the cutting edge of the tool on the one hand and the workpiece and guide pads of the tool on the other. In addition, the cooling lubricant leads to the constant removal of chips from the cutting zone, which makes surface-damaging and time-consuming chip removal strokes unnecessary and therefore improves the quality of the borehole and the productivity of the processes. For the production of deep holes, two different tool types are distinguished. On the one hand, there are tools with an asymmetrical single cutting-edge design. These deep hole drilling tools include single-lip deep hole drills, the single-tube system (BTA deep-hole drilling) and the double-tube system (ejector deep-hole drilling), which are referred to as the \"classic\" deep hole drilling processes. On the other hand, there are tools with symmetrically arranged cutting edges. These include spiral deep hole drilling tools and double-lip deep hole drilling tools, which can also be assigned to the deep drilling processes due to the drilling depths to be achieved with them. Deep Hole drilling was made originally in china.
The mentioned tool types differ with regard to the realizable diameter range, the achievable l/D ratios, the surface quality and they're productivity. Symmetrical tools can only be used in the small diameter range of D = 0.2 ... 32 mm to produce holes with an l/D ratio up to a maximum of l/D = 85, the standard is an l/D ratio of l/D = 30. With asymmetrical tools, holes in the diameter range of D = 0.5...2000 mm can be produced and the upper limit of the l/D ratio is usually limited by the machine dimensions. The figure shows selected deep hole drilling methods with their usual application diameters, whereby it becomes clear that deep hole drilling methods do not compete with each other in all diameter ranges. The advantage of the symmetrically designed tools compared to the \"classical\" deep hole drilling tools in the small diameter range is the feasibility of significantly higher feeds f, which can be 6 times higher compared to the usual values for single-lip deep hole drilling.
In addition to the high l/D ratio, the \"classic\" deep hole drilling methods are characterized by high productivity and high surface quality compared to the conventional drilling methods with twist drills. The high drilling quality is characterized by low surface roughness, small diameter deviations and a high geometrical accuracy. Important for the good surface quality is the asymmetrical design of the deep hole drilling tools. The \"classical\" tools for single-lip deep hole drilling, BTA deep hole drilling and ejector deep hole drilling are, with a few exceptions, designed asymmetrically and have a secondary cutting edge (circular grinding chamfer) and guide pads. Due to this design features, a certain amount of the cutting forces during the process is transferred via the guide pads to the bore hole wall. These force components at the tool head are supported at the produced borehole wall and thus guide the tool in the bore hole itself. The distribution of the process forces during deep hole drilling is therefore different from conventional drilling, where the forces are largely absorbed by the tool shank and thus by the machine spindle. Due to the process force distribution to bore hole wall in deep hole drilling, the drill guides itself and thus the process benefits from a comparatively low straightness deviation. The \"support\" of the guide pads on the borehole wall also results in a forming process that (ideally) smooths the bore hole wall. Due to this forming process the surface roughness caused by the engagement of the cutting edges during drilling can be decreases by about 70%. Thus very high surface qualities with bore hole tolerances of IT 9 to IT 7 can be achieved by deep hole drilling processes. Subsequent steps to improve the surface quality of the bore hole can often be reduced or eliminated completely. A further advantage is the low burr formatio