Manual grinding of high speed steel drill bits

  1. The edge is placed flat against the grinding wheel surface

This is the first step in the bit’s position relative to the grinding wheel. Some inexperienced operators lean on the grinding wheel and start sharpening the edge before they even straighten it out. This must not wear well. The “edge” here is the main cutting edge. “Leveling” means that the main cutting edge of the sharpened part is in a horizontal position. “Wheel surface” refers to the surface of the grinding wheel, “against” is slowly close to the meaning. At this point, the drill bit cannot touch the grinding wheel;


  1. Oblique drill shaft repair sharp Angle

Here refers to the axis of the bit line and the location of the relationship between grinding wheel surface, “Sharp Angle” is the half of the point Angle 118 ° ± 2 ° , it’s about 60 °. This position is very important, which directly affects the size of the point Angle of the drill bit, the shape of the major cutting lip and the chisel edge Angle. Do not neglect to lay down the bevel Angle in order to lay down the cutting edge, or to lay down the axis in order to lay down the cutting lip. These errors are common in practice. At this point, the drill bit is ready to contact the grinding wheel in the correct position;


  1. From the edge to the back of the grinding

This refers to the grinding of the bit’s edge slowly along the entire back surface, starting from the edge of the bit. This facilitates heat dissipation and sharpening. At this point, the bit can gently contact the grinding wheel for a small amount of edge grinding. When grinding the edge, observe the uniformity of spark, adjust the hand pressure in time, and pay attention to the cooling of the drill bit. When the edge grinding starts again after cooling, continue to set the position. The Universal Tool Grinder is offered by Purros Machinery Co., Ltd., a professional OEM/ODM tool grinder manufacturer and supplier, End Mill Grinder, Twist Drill Grinder, Lathe Cutter Grinder, Carving Tool Grinder, Drill Sharpener, Universal Grinder, etc.

The Universal Tool Grinder is offered by Purros Machinery Co., Ltd., a professional OEM/ODM tool grinder manufacturer and supplier, End Mill Grinder, Twist Drill Grinder, Lathe Cutter Grinder, Carving Tool Grinder, Drill Sharpener, Universal Grinder, etc.

Manual grinding of high speed steel bit is subject to human factors. Manual grinding will result in a large error of the drill bit due to the difference between human experience and personal intuition. But machine repair and grinding completely avoid this problem. Drill bit grinding machine is more accurate, and the error is small, the human factors are relatively small. Operators do not need to go through professional drill grinding training can be on duty. The operation of the drill bit grinding machine is very simple and the efficiency of the drill bit grinder is very high. Therefore, now many companies that use drill bits choose to buy a drill bit grinding machine to repair the damaged drill bits, which saves a lot of cost. Our tool grinding machines are of very good quality and have been well received by our customers in the market. Welcome to inquire purchase.

What are the differences between machining center and drilling & tapping center?

Now with the vigorous development of industrial manufacturing industry, various industries are using machining center equipment in abrasive tool processing. Many customers still know machining center better. When someone says drilling and tapping center, many people are not clear. Today, let’s talk about the similarities and differences between machining center and drilling & tapping center.


Same points


Machining center and drilling and tapping center, literally, have the word “center”. It can be seen that they are both metal cutting machine tools and CNC processing equipment. In terms of style and function, machining center and drilling and tapping center are very similar.




  1. Application: Machining center is widely used, mainly for processing plane, surface and other shapes of equipment. Drilling and tapping centers are mainly used for drilling and tapping. Machining center can be used for milling, but machining center can only do slight milling, because the power of drilling and tapping center spindle is not very large, it can not carry out heavy milling.
  2. Shape: drilling and tapping center is smaller than machining center in shape.
  3. Tool library selection: machining center is mainly a hat-type tool library and a disc-type tool library, while drilling and tapping center is mainly a turret-type tool library and a turret-type tool library.
  4. Fast moving speed: drilling and tapping center adopts linear guide rail, which is faster than machining center. The machine tool processing efficiency is obvious.
  5. Price: As far as machinery is concerned, the price of machining center is higher than that of drilling and tapping center.
PURROS Multiaspect Special Purpose Machine

PURROS Multiaspect Special Purpose Machine

Many machinery plants choose to use drilling and tapping centers. Both drilling and tapping centers and machining centers can cause tool damage and wear. In some cases the tool has not been completely damaged, many can be used after repaired with the drill bit grinding machine. For example, worn bits can be repaired with a drill bit sharpener for more than 90% of worn bits. The repaired bit can be reused. We produce a variety of tool grinding machines, you can choose the right tool grinding machine according to your needs to complete the repair work.

What are the difficulties in drilling stainless steel?

The difficulties of stainless steel material processing mainly include the following aspects:

  1. High cutting force and high cutting temperature

This type of material has large strength and large plastic deformation during cutting, so the cutting force is large. In addition, due to the poor thermal conductivity of the material, the cutting temperature is increased, and the high temperature is often concentrated in the narrow area near the cutting edge, which accelerates the tool wear.


  1. Severe work hardening

Austenite stainless steel and some high temperature alloy stainless steel are Austenite structure. These materials tend to be hardened when machined, often several times as much as plain carbon steel. The cutter is cut in the hardened area to shorten the tool life.


  1. Easy to stick the tool

Both Austenite stainless steel and Martensite stainless steel have the characteristics of strong and tough chip and high cutting temperature. When the strong and tough chip flow through the front surface of the cutter, the phenomenon of bonding, welding and other adhesion will occur, affecting the surface roughness of the processed parts.


  1. Tool wear is accelerated

The above materials generally contain high melting point elements, large plasticity and high cutting temperature, which make the tool wear faster and the tool wear and change frequently, thus affecting the production efficiency and increasing the tool use cost.

Continue reading

Problems encountered during the operation of the alloy bit and its solution

What kind of material is suitable for what kind of tool?

What kind of material is suitable for what kind of tool?


Problem Solution
The front end of the alloy bit is broken Aimed at the bit again
Repair with a drill bit grinder
Improve stability, re-clamp parts, shorten overhang of alloy bit
Check speed/feed
The outer diameter of the alloy bit is worn Aimed at the bit again
Improve stability, re-clamp parts, shorten overhang of alloy bit
Check speed/feed
Repair with a drill bit grinding machine
Oversize/undersize holes To aim at tungsten steel drill bit
To reduce feed
Check speed/feed
The alloy bit is clogged with chips in chip removal tank Increase coolant flow, clean filter, clean bit coolant hole
To reduce feed
Improve stability, re-clamping the parts, shortening the overhang of alloy bit
Check speed/feed
Increase speed
vibration To reduce feed
Improve stability, re-clamping the parts, shortening the overhang of alloy bit
Check speed/feed
A small crack in the cutting edge Repair with a drill bit grinder
Aimed at the bit again
Check the carbide number
Increase speed
Hole asymmetry To reduce feed
Improve stability, re-clamp parts, shorten bit overhang
Check speed/feed
Alloy tool has short life Increase coolant flow, clean filter, clean bit coolant hole
Improve stability, re-clamping the parts, shortening the overhang of alloy bit
Check the carbide number
Check speed/feed

Q&A when buying PG-13A and PG-13A

Drill Bit Grinder, Drill Bit Sharpener, Drill Bit Sharpening Machine, PG-13A Drill Bit Sharpening Machine, Drill Bit Grinder for Sale, Best Twist Drill Bit Grinder Manufacturer, Cheap Twist Drill Grinder

PURROS PG-13A drill bit grinder

Drill Bit Grinder, Drill Bit Grinder for Sale, Twist Drill Nose Sharpening Machine, PG-13D Patent Drill Bit Grinder, Drill Bit Sharpening Machine, Rapidly Grind Drill Bit, Drill Bit Grinder Manufacturer


PURROS PG-13D patent drill bit re-sharpener grinder


Q: what’s this little machine for?

A: this little machine is specially designed for grinding ordinary twist drill.


Q: how many ranges of diameters can it grind?

A: the grinding range of this model pg-13d is 3-13mm.


Q: do you have a drill bit grinder with a larger grinding range? For example, the grinding diameter reaches 20mm.

A: yes, different types of drill bit grinders have different diameters for grinding. For example, the grinding range of pg-13 is 3-13mm, the range of pg-26 is 13-26mm, and the grinding range of pg-g3 is 3-26mm, and the maximum grinding range can be 3-32mm by selecting machine parts.


Q: what’s the difference between model A and model D?

A: the type A grinder can only grind the land angle and lip relief Angle of the drill bit, but cannot repair the chisel edge of the drill bit. Such A drill can only drill holes, and the accuracy error is relatively large. The type D drill bit grinding machine can grind the land Angle and lip relief Angle of the drill bit, and also repair the chisel edge of the drill bit, so that the drill bit has accurate drilling and easy chip removal.


Q: is this grinding wheel on the market?

A: yes, our grinding wheel is a national standard. It is sold in the market.


Q: how long is the warranty on your machine?

A: because we have small equipment, the vulnerable parts are motors and grinding wheels. The grinding wheels are international standard and can be bought in the market, so our machine has a one-year warranty.

How to reduce the abrasion of drill bit?

The drill bit is arguably the most commonly used key component, and it is easy to wear out. How to reduce the abrasion of drill bit is very important?


What is abrasion?

The wear caused by the two components squeezing each other and causing relative motion.

For example, between the tool tip and milling and planning materials. In the process, tiny particles on the surfaces of the two components are detached from the elements.

Common causes of tool wear:

All components of the tool are more or less worn by milling and planing materials.

If a single component is damaged, such as blade tip, steel tool body, gasket or spring, the entire tool should be replaced. This prevents damage to the relatively expensive tool holder system, and the replacement of the tool holder system is more complex.


Common tool wear includes the following reasons:

  1. Incorrect installation;
  2. Use components from different manufacturers;
  3. Incomplete cleaning: milling and planing materials on the tool plate and continuous accumulation;
  4. Choose the wrong tool (different type of machine should choose different type of tool);
  5. The sprinkler system in the housing of the milling and planing drum is short of water supply.

How to reduce tool wear and tear?

Tool wear is not entirely avoidable, but it can be minimized.

  1. Sufficient water supply is the basic premise to ensure the normal rotation of the tool.
  2. Select the right tool according to milling and planing materials, which can also optimize the use and reduce wear.
  3. Pay attention to daily thorough cleaning;
  4. Regularly check the tool, and timely detect and deal with the wear and tear or damage of components;
  5. Regularly maintain and inspect the sprinkler system;
  6. Select milling tools suitable for working conditions.

Correct installation to reduce wear and tear:

  • Before installation, check whether there is any foreign matter in the inner diameter of the tool holder and confirm whether cleaning is necessary.
  • Use proper tools (copper hammer or pneumatic insert tool) to prevent damage to the tip.
  • Manually check the tool rotation (turn the tool by hand).
  • Only proper maintenance tools can minimize the wear and tear of key components.

This greatly saves the cost and ensures the efficient operation of the machine. In the daily maintenance, we recommend our drill bit grinding machine. This tool can be used to repair your drill bit in case of wear and tear. Allow your drill to be reused and the life of the drill is increased, and your money is saved.

What are the rewards for drill bit sharpening machines?

the drill bit grinding machines produced by purros are sold all over the world

  1. Save more than 70% of the cost of drill bits


  • 1). Old tools become new tools. A drill can be sharpened at a small cost. It saves you a lot of money.
  • 2). Old tools such as drill bit/milling cutter tool can be grinded and reused.
  • 3). The grinding capacity of each tool is only 0.4mm, and each tool can be grounded more than 10 times.
  • 4). It solves the problem of traditional manual grinding tool (non-standard, short life and long time).
  • 5). High grinding precision, extend tool’s life.
  • 6). It can not only grind high-efficiency drill bit, but also can grind common drill bit into high-efficiency drill bit.


  1. Improve machining efficiency by 3-6 times

  • 1). It takes an average of one minute to repair and grind a drill bit, with high grinding efficiency.
  • 2). Our bit grinding machine has high precision and good processing quality .
  • 3). The life of the drill grinding machine is long and the auxiliary time is small.
  • 4). This machines have fast to feed speed and high processing efficiency.
  • 5). The machines have been reduced processing procedures and improved work efficiency.


  1. Solve more than 80% of processing problems

  • 1). With one machine can repair and grind drill bits (milling cutter) of various diameters.
  • 2). The quality of the grinding machine is good, and the precision of the drill bit is guaranteed.
  • 3). Drill bit grinder can improve the cutting performance of the tool and improve the machining efficiency.
  • 4). The machines have small cutting load and long tool’s life.
  • 5). The drill bit grinder can reduce the breaking edge of milling cutter and improve the service life of milling cutter.
  • 6). Our grinder machine can solve the problems of hole deviation, hole expansion, hole shrinkage and burr in general hole processing.
  • 7). Using our machines will solve the problems of short drill life, low drilling efficiency and difficult chip discharge caused by deep hole machining.


  1. Provide perfect after – sales service

  • 1). Provide customers with the most professional and economical purchasing plan fro free of charge.
  • 2). Help customers to check the machine platform for free, and develop special grinding tool’s SOP.
  • 3). Help customers improve the processing technology and improve the processing efficiency for free of charge.
  • 4). Provide customers with professional tool’s knowledge and advanced processing technology for free of charge.


Tips for using drill bits

Although the drill is worn out, it can be repaired by a drill bit grinder. However, in ordinary use, different drill bits also have many tips. If you do not know how to use the drill bits, it will cause serious damage to the drill bit. It is impossible to use the drill bit grinding machine for repair, and the cost will also increase.

Operation Tips

There are some pointers that, when followed, will retain the life of the above drill types.

  • Hard materials need slow drilling speeds, and soft materials need faster drilling speeds. And as the hole deepens, the speed decreases. For the precise recommended drilling speed, the HSS drill can see the following formula.
  • You can drill holes first to allow for more accurate drilling.
  • Always make sure the drill is sharp to ensure less load on the power tool and better cutting effect.
  • If you plan to drill down to a piece of wood, use a wooden pad at the back of the job to prevent the material from breaking.
  • To achieve better drilling results, the cutting fluid is applied to the bit when drilling metal (except brass and iron).
  • Large bit will transfer a lot of reaction force to the drill bit, so be ready to stick with it.
  • All drill bits should be regularly removed from their flutes and airflow should be added around the drill to cool it.
  • Always apply pressure on a straight line with a drill. You should have enough to keep the bit together, but not too much, the tool’s motor gear or the bit deflected.
  • To prevent material breakouts, reduce the pressure you apply and get the drill through the last part of the hole.
  • Be sure to let the drill cool naturally. Don’t force them to cool in water (or any other liquid).
Drill bit geometry has several characteristics buy drill bit grinder

Why are twist drill bit especially easy to wear?

There are several disadvantages to the twist drill:

(1) the internal and external difference of the front Angle values of the points on the main Cutting Edge of standard twist drill is too large. The front Angle of the main cutting edge at the outer edge of the bit is about +30; The front Angle near the core is about -30.

Close to the front Angle of the drill center is too small, causing the chip to deform large, the cutting resistance is large; Near the outer edge of the anterior horn is too large, in processing hard materials, the strength of the cutting edge is often insufficient.

(2) the transverse edge is long, and the front Angle of the transverse edge is a large negative value, which is -5 4°~-6 0°, which will produce a large axial force.

(3) compared with other types of cutting tools, the main cutting edge of standard twist drill is very long, which is not good for cutting and cutting.

(4) take place after the deputy vice cutting edge of blade Angle is zero value, cause vice knife after the friction between the surface and hole wall, cutting temperature rise, the outer edge of the corner of bit wear is bigger, has processing surface roughness.Continue reading

What are the basic steps of using the drill bit grinding machine?

Follow these steps to use the drill bit grinder:


  1. Select the correct and reasonable grinding wheel (type and model).
  2. For the new tool, first check the main geometric parameters and record, especially to record the cutting edge, chamfering and horizontal blade of the drill bit or tool.
  3. First enter the data of the grinding wheel, and then enter the data of the drill bit sharpening machine.
  4. After the grinding, the main parameters of the cutter are tested and compared with the standard data of the tool grinding, and it is modified after comparison with the tool grinding standard until the whole grinding is finished.

PG drill bit grinder operational processes, Drill Re-sharpener, Drill Bit Grinding Machine Manufacturers, drill bit grinder, twist drill bits, drill bit

If you do not know how to choose the model of the drill bit grinding machine for your tool, you can contact us. We have professional customer service staff to help you find the most suitable product.