PCB drilling cost analysis
The materials used in a circuit board will affect its cost. Standard PCBs laminated with FR4 material. but this will not suffice for boards manufactured for high-intensity uses. such as those common in the aerospace and fuel industries.
Thermal Reliability: Will the board be capable of performing. under the range of temperatures expected for the tasks in question? Certain boards need materials of a higher thermal rating than standard boards.
Temperature Reliability: Can the material withstand an expected range of atmospheric conditions. within a controlled setting without overheating? PCBs intended for high-temperature working operations need materials that pass these tests.
Heat Transfer: Will the board withstand high-intensity loads . without transferring undue levels of heat to attached and adjacent components? The right material will need to pass this test for the uses in question.
Signal Performance. Will the material help uninterrupted electrical signals. throughout each operating cycle of a given machine? Will the signal withstand a necessary range of temperatures and other environmental factors? These concerns are integral to the performance of a PCB.
Mechanical Properties: Does the material have enough physical composition to. withstand a plausible range of physical stresses? Can the board pressed into a tight slot without cracking? Can it dropped several feet without breaking? Any PCB ideal for sale will need to pass drop tests and other performance criteria.
As a rule of thumb, operations that involve higher frequencies need materials. of a higher grade than standard FR4. As such, the materials used in a microwave PCB could be 10 times more costly than the materials. used for the board in a calculator or other handheld device.
The size of a PCB and its panel use are two of the most crucial factors that affect the price. The size of a board will generally determined. by the number of circuits required for the corresponding device.
A PCB in something as small as a digital watch will need fewer components. and be less costly to produce than a computer or laptop PCB. Likewise, the PCB in a large piece of industrial machinery will be larger. than the boards contained in most home electronics.
In PCB manufacturing, the following dimensions are among the most common:
18 X 24″ (457 x 610mm)
18 X 21″ (457 x 533mm)
21 X 24″ (533 x 610mm)
The amount of space consumed by components on a board will also affect the price. Granted, some boards designed with less consideration of efficiency and production costs.
For example, an 18 x 24 PCB that contains three columns. and two long rows of panel use would be an efficient use of board space . because active components will consume the majority of the panel. But, an 18 x 24 PCB that contains one column and three rows would be less efficient because the margins will be wider. yet still costly due to the material.
the dimensions of your PCB design will be one of the main determining factors of the price. Even if you manufacture a small PCB at high volume, the total cost might be less than that of a low-volume, large PCB.
Another determining factor of board price is the number of layers involved. For obvious reasons, PCBs with three or more layers cost more to produce. than boards that consist of two layers. The pricing issue affected by the types of material used and the size of the board itself. , thick boards with many layers need more work to manufacture.
price increases on a layer-by-layer basis can broken down as follows:
1L to 2L: 35 – 40%
2L to 4L: 35 – 40%
4L to 6L: 30 – 40%
6L to 8L: 30 – 35%
8L to 10L: 20 – 30%
10L to 12L: 20 – 30%
Some of the most significant increases. in manufacturing cost occur once a second layer added to a board. From there, an more two boards will raise the cost by at least one-third of the previous price. The price increases are generally less steep once a design. crosses the eight-layer threshold.
With each layer added to a PCB, more production steps involved in the lamination process. This requires more time to achieve and necessitates a larger supply of material. The steps involved in multi-layer board construction. also increase the possibility of production defects. To offset the possible cost of errors. PCB makers will often factor this into quotes on multi-layer board production.
Depending on the material used in a board design. you might need more layers to ensure a solid composition. If a PCB expected to endure a high amount of stress. and still have a certain degree of flexibility. these factors will determine the layer count. as well as the material.
A minor factor to consider of PCB production. involves the costs associated with a given finish. Some finishes boast higher grades and offer longer shelf life. thus adding to the cost of production. One of the more common. and low-cost surface treatments is HASL, which offers good solderability. but rated on other counts. ENIG. by comparison, scores in most categories yet only commands a slight price difference.
Each of the surface treatment options offers unique features:
IMM Ag: Solderability, Al wire bondable
IMM Sn: Solderability
ENIG: Solderability, Al wire bondable, contact surface
ENEPIG: Solderability, Al wire bondable, contact surface
Elec Au: Solderability, Al/Au wire bondable, contact surface
The number of layers may also determine. whether the finish impacts the price of PCB production to a significant degree.
standard pcb drill sizes
One of the important, if not crucial, factors. that can influence the cost of a PCB production is the size of the holes in a board. The costs associated with holes. can also determined by the number of holes required for the board. as well as the type of material and thickness of layers drilled. more holes need more work. especially if the holes in question are challenging to drill due to tininess. and board thickness.
The sizes of the holes in a board design are the most crucial price determinants in this area. If the holes are super-thin, they will need special tools to produce. For example, a hole that has the diameter of a hair strand will be more challenging to create. than a hole that equals the diameter of a typical screw hole. Such holes need more work and a specialized skill set to dp.
Whether the holes sized or microscopic. the price of the board production can also impacted by the number of holes contained in a given design. If a board contains dozens of holes, this feature will added on to the price due to the extra work involved.
more hole-related factors that can impact the price of a PCB production. are the thickness of the material and the number of layers contained in the board design. If a board consists of 10 or more layers, hole-drilling will be a more time consuming task due to the thickness. If the material is super-strong and hard to drill, this will also impact the price.
standard drill sizes for pcb manufacture
when the component is Xmm, you should drill a hole that is X+ 0.3mm. If the component is 0.4mm, then drilling a hole that is about 0.7- 0.8 mm may be necessary. If you make the whole bigger, you are likely to end up with more waste when you start soldering.
PCB drill tools manufactured in increments of 0.05 mm. We convert the drill size given in the drill files or tool lists into milimeters and rount ot hte nearest 0.05 mm.
Drill size of 31 mil – converted to 0.7874 mm is then rounded to 0.80 mm
Drill size of 32 mil – converted to 0.8128 mm is then rounded to 0.80 mm
Drill size of 33 mil – converted to 0.8382 mm is then rounded to 0.85 mm
pcb hole size calculator Trace and Space
For a current to transfer on a PCB without the threat of overheating and damage to the board. there must be enough trace width in the board design. On boards of all sizes, a simple correlation exists between the trace width. and carrying capacity. A section of the former will determine the latter. Moreover, trace cross-sections correlate to the thickness of copper.
It must noted that trace carrying capacity. does not correspond to the cross-section space. In fact, the amount of current that a trace can hold, at maximum, cannot calculated. regardless of the trace width or temperature rise. The carrying capacity of a current can also impacted by pads, vias and other board elements.
On a board with many pads, you might encounter a trace of exceptional capacity. If this is not accounted for in the soldering process. an excessive cross-sectional area might created. and transient surges are liable to occur.
To avoid these situations, board makers will enlarge the trace width, if possible. they can add extra solder mask to the traces that might otherwise be prone to burn. These steps can add to the price of a PCB production.
pcb drill bit size
Until recently, the thickness of a PCB. had played only a minor role in the cost, though all that is liable to change in the coming years. Thicker material can be costlier to buy. laminate and form into a printed circuit board. especially if the design itself is intricate.
Thinner material will generally put a line of PCBs into a lower cost bracket. because less material required for the production at hand. The costs of a board in regards to thickness can also impacted by the type of material used in a given production.
The standard thickness for a PCB is 1.6mm (0.063″). In recent times, thicker boards have become more expensive. though an industry-wide going rate has never established. it depends on the manufacturer whether a thinner board of 0.8 mm will cost less. or equal to a board of standard thickness.
The price of a thicker board could be higher if it also has a larger aspect ratio. If the board consists of many layers for its thickness and features wide dimensions. the board will need more material and involve more work in its construction. so, it might not be the thickness of the board that impacts the cost. as much as the measurements or the number of layers that add to the thickness.
drilling cost per foot
In the manufacturing industry, hole-drilling operation is almost always unavoidable. In particular in electronic manufacturing, drilling holes on the printed circuit board (PCB). is one of the most crucial processes. With the escalating growth in demand for computers. and electronic gadgets, PCB assembly has become a competitive market. The increasing variety of products in need of PCB has made it. inevitable for circuit board manufacturing industry. to automate the hole-drilling operations.
Many industries have adopted. the computer numerical control system in automating the hole-drilling operations. because of its control flexibility. In all machining processes. time spent on both positioning the cutting tool. and carrying out the machining operation. and the hole-drilling operation is of no exception.
Due to the point-to-point tool movement in hole making. and need of different tools for making each hole. a considerable amount of the processing time spent on switching tools. and moving the table from one location to another. The survey reported that tool movement. and switching time take 70% of the total time in a manufacturing process, on average. Thus, optimization of hole making operations. can lead to significant reduction in machining time. which carbide micro improves productivity of manufacturing systems.
A crucial issue in manufacturing is cost effectiveness. Production costs must minimized if the product is to compete in the marketplace. Maximizing the production of products that meet customer requirements. is the prime aim of a manufacturing enterprise. Thus, any strategy that can adopted to cut the production timewill. have much impact on achieving the firm’s objectives .
Optimization of drill path can lead to significant reduction in machining time. which improves productivity of manufacturing systems. In a batch production of a large number of items to drilled such as carbide micro printed circuit boards (PCB). the travel time of the drilling device. is a significant part of the manufacturing process. To increase carbide pcb manufacturing productivity and to reduce production costs. a good option is to minimize the drill path route using an optimization algorithm.
printed circuit drill holes Material and pcb fabrication processing costs. as well as drilling cost per foot, determined by several factors following.
pcb drill calculations spreadsheets here we using it as an analysis matrix. a cost model specifically designed for drilling cost analysis. and generated with the use of a computer spreadsheet program.
The advantage of using a spreadsheet is that. it allows changes to made in, for instance, specific material prices. and processing times or parameters. and allows instantaneous viewing of the resulting effects on the carbide micro total drill cost. the cost per panel. and the average cost per hole.
Knowing the cost per hole is important because. it allows comparing different jobs or processing situations. Following is a step-by-step description of. how to construct a circuit board drilling cost analysis
drill for pcb
PCB manufacturing costs. can also impacted by the unique design elements in a given production. If you come to a PCB maker with custom specifications, this could raise the cost of its production. even if the board itself is small and consists of only one or two layers. The real determining factor in this regard will be. whether the features in question need special tools or skills to achieve. Examples of custom specifications could include:
Contoured Edges: PCBs with rounded edges could cost more to produce. especially those that need z-axes routing.
Side-Plating: Some PCB designs specify metal edges for boosted EMC strength.
Solder Mask Clearance: If extra clearance. and thickness needed of the solder mask, this will increase costs.
Special features need specialized skill sets. If your design involves details that are hard to produce. and are not the types of details that PCB makers assemble on a regular basis. this could limit the number of people who could work on the production. This, in turn, could lead to a more time-consuming production. If the production takes more hours to finish, your boards will cost more in the end.
Special tools are often required for unique board designs. If the board requires many holes in some unusual size that does not match one of the standard diameters. the company that handles your order might need to buy the necessary instrument. and charge you for the costs involved. you might asked to supply the tools required for a special design request. These are agreements that should stipulated in advance of any contract with a PCB maker.
To avoid high costs that might stem from unique PCB design requests. calculate the potential price of your design in before production. Determine the custom specifications of the design. and the steps required to bring it to fruition. Make sure these details understood by the PCB maker to avoid costly trial and error.
PCB drilling machine Time
Table A in the drilling cost analysis matrix. used to calculate the total time that required to complete the job.
First, the different PCB drill sizes. and their respective total drilled holes per panel. as well as the total number of panels to drilled determined and entered in the spreadsheet. this allows the spreadsheet to calculate the total number of holes for each size to complete the job
Second, using the appropriate drilled stack height the total number of drilled stacks. and the total number of drilled hits per drill size can calculated. The total number of drilled hits (drill strokes) is the total number of drilled holes per panel (b). divided by thenumber of panels per drilled stack
Third, the number of total drilled stacks divided by the number of stations per machine. (stacks per load [h]) to calculate the number of machine loads(i).
Fourth, the total pcb drill time per load required per drill size
is entered to calculate the total machine time for each drill size (k).
Fifth, the total times of each of the drill sizes are simply added up to. arrive at the total time required to finish the job. An option is to enter the total drill time per load instead of entering the time for each of the drill sizes. and multiplying the total drill time per load by the number of machine loads to. determine total machine time.
pcb standard drill sizes mm chart
PCB Drill Bits
The drill bit cost needed to complete the job may. determined after the average cost per drill bit use has calculated. To find the average cost per drill bit use. the typical number of repoints for the particular size (o) multiplied. by the cost of each repointing (n).The resulting cost. added to the new drill bit price (m), is the cost per drill bit life (p). By dividing the cost per life by the number of uses (q) per life (the number of times the bit repointed +1).
you arrive at the average cost per drill bit use (r). Next, by dividing the total number of hits per drill size (s) by the number of greatest hits per drill bit use (t). the number of required drill bit uses (u) for each size may determined. Then calculate the total cost per drill bit size (v) by multiplying the number of uses (u) by the average cost per use (r). The sum of the total costs of each of the drill bit sizes (v) brings you to the total cost of drill bits needed for the job. This cost, of course, is true only with the assumption of no drill bit breakage.
This is standard PCB Drill Set from Carbide 3D that. supplies you with more options for drilling into copper clad. on your Shapeoko or Nomad CNC machines. carbide micro Each set includes three 0.5mm, five 0.7mm, and two 0.9mm PCB drills each with a 0.125" shank. Additionally, each drill made of solid carbide to ensure long lasting use.
If you are wondering how best to use this kit, make sure to check out the free to use web app, carbide pcb Copper. Carbide Copper is CAM software to let you mill print circuit board with your CNC machine.
Entry and Backup board
Entry and backup material cost per stack (y). determined by multiplying the stack size(square foot per panel [x]) by the cost per square foot. Remember to divide the backup cost by 2 since each backup panel may used twice. Total material cost (aa) calculated by multiplying cost per stack (y). by total number of drilled stacks (z).
Burden and Labor
pcb drill Using typical burden and labor rates per hour (ab). these values multiplied. by the number of hours to complete the job (determined in Table A) to calculate the total burden. and labor costs (ac).
Total Drilling Cost and Cost per Hole
After entering the required data in Tables A through D of Fig. 24.11, the total drilling cost. and the cost distribution (see Table E) as well as the drilling cost per panel. and the cost per hole (see Table F) can calculated. Because the drill set cost per hole ranges around 1⁄10 of a cent. a more accurate and easier way to comprehend this value is by showing the average cost per 1000 holes. as done in the cost model.
Drill holes in fabricated circuit board processing
1.Tool lists for drill files are ALWAYS read ( and interpreted) by our CAM systems. as finished hole sizes ( so final diameter of the whole after plating and surface finish )
2. PCB drill tools manufactured in increments of 0.05 mm. We convert the drill size given in the drill files or tool lists into milimeters and rount ot hte nearest 0.05 mm.
Example : Drill size of 31 mil – converted to 0.7874 mm is then rounded to 0.80 mm
Example : Drill size of 32 mil – converted to 0.8128 mm is then rounded to 0.80 mm
Example : Drill size of 33 mil – converted to 0.8382 mm is then rounded to 0.85 mm
3. If possible, provide separate product details drill set for plated (PTH) and non-plated (NPTH) holes. If this is not possible, always specify different tools for PTH and NPTH holes and mark. which tools are PTH and which tools are NPTH.
4. When no PTH/NPTH info given we use the following rules to determine PTH/NPTH:
For 0-layer and 1-layer boards: ALL holes considered as NPTH by default.
For 2-layer and multilayer board carbide: ALL holes considered PTH except the following cases. which considered NPTH:
Non-connected holes without copper pads.
Non-connected holes where the copper pad size is equal to. or smaller than the drill TOOLSIZE (the copper pad. will removed in single image preparation)
Connected holes with a copper pad on 1 side (outer), no connection on any other layer (outer or inner). and no pcb milling copper pad on the other side (outer).
5. Finished hole sizes (ENDSIZES) smaller than or equal to 0.45mm (18mil). are by default considered as VIA holes You can adjust this limit by selecting. another tungsten steel value for” Holes <= may reduced” in Board technology
Holes with this size or smaller are via holes
IMPORTANT: This default via-rule affects the standard tolerance on. via hole ENDSIZE diameter – point 7 below
6. To allow for the plating in the hole we drill holes before plating at a larger size (drill over-sizing)
The conversion rules from finished hole ENDSIZE to production TOOLSIZE are:
TOOLSIZE = ENDSIZE 10pcs pcb
+ 0.10mm (4mil) for drill bit Plated Through Holes (PTH)
+ 0.00mm for Non drill bit Plated Through Holes (NPTH), so toolsize = endsize
pcb drilling technology
Drilling is the most expensive and time-consuming process in PCB manufacturing end mills. The PCB drilling process must implemented since even a small error can lead to a great loss. The drilling process considered the most critical. and bottleneck of printed circuit board manufacturing. A PCB design engineer must always look into the board manufacturers’ capabilities. before placing an order.
The print circuit board drilling process is the foundation for vias. and the connectivity between different layers. The downsizing of electronic devices such as TVs. and phones has led to the transformation from stationary to portable. High-quality micromachining required to bring down the size. The drilling process plays a vital role in making this possible. Hence, the implemented drill technology, matters.
Basically, there are two kinds of drilling technologies, mechanical and laser drilling.
The print circuit board mechanical drills have less precision but are easy to execute. This drilling technology implements drill bits. The smallest hole diameter that can drilled by these drills is about 6 mils (0.006”).
The laser drills, but, can drill way smaller holes. Laser drilling is a non-contact process. where the workpiece and the tool do not come in contact with each other. Here, the drill depth can controlled.
The laser technology used to drill blind and buried vias with ease. Here, a minimum hole diameter of 2 mil (0.002”) can drilled with precision.
After the print circuit board lamination process, the laminated board loaded on a panel of exit material on the drill bed. The exit material lessens the burr formation. Burr is the protruding part of copper formed. when the drill spindle penetrates through the board. On top of this panel, more stack-ups loaded and aligned. In the end, a sheet of aluminum foil placed over this entire stack-up. The Aluminium foil avoids entry burr. and also dissipates the heat generated by the spinning drill bit. Once the required number of holes drilled. the boards sent for deburring and desmearing process.
Since the quality of the drilled hole is a crucial aspect. tool geometrics must considered. High-Speed Steel (HSS). and tungsten carbide (WC) are commonly used tool materials for drilling of composites. Carbide tools offer better tool wear and tool life during the machining of GFRP. The cemented carbide drills are generally used in cnc engraving PCB drilling. The PCB drills have a point angle of 130° with a helix angle from 30° to 35°.
drill bit size for pcb holes problem
Laser Drill Limitations
A PCB made UP of copper, glass fiber, and resin. These materials have different optical properties. This makes carbide pcb hard for the laser beam to burn through a board .
The Life Span of Mechanical Drills
The mechanical drills can used for 800 hits when used on softer materials like FR4. For denser materials like Rogers, the lifespan reduced to 200 counts. If a PCB maker ignores this then it will result in faulty holes which will turn the board to a scrap.
If the designer understands the things that happen on the shop floor. he will have a better perception of how his design brought to life. With this insight, the PCB designer ensures the designs are manufacturable. This, in turn, reduces the cost and the product can delivered in a minimum turnkey time
The drilling machine is a preprogrammed Computer Controlled (CNC) machine. The drill pcb print takes place based on the XY coordinates fed into the CNC system. The spindles rotate at a high RPM and ensure an accurate drill hole in the PCB. When the spindle rotates with a rapid speed, heat generated. due to the friction between the hole wall and the spindle. This melts the resin content on the hole walls and results in a smear of resin. Once the required holes drilled the exit and entry panels discarded. This is a small gist of what goes happens on the shop floor.
Unlike the print circuit board etching. and plating process, the drilling process doesn’t have a fixed super sharp duration. The drilling time varies in the shop floor depending on the number of holes to drilled. This is what happens behind the curtains in PCB manufacturing unit.
Two significant aspects to considered in the drilling process:
The aspect ratio
Drill to copper clearance (Drill to the nearest copper feature)
Aspect ratio is the ability to plate copper inside the drill press holes(vias). The copper plating of the interior part of holes is a tedious task. when the diameter decreased and the depth of the hole increased. This requires a plating bath with a higher throwing power so that the liquid could gush into the tiny holes.
part number Aspect ratio (AR) = (Depth of the hole/ Diameter of the drilled hole)
The aspect ratio is 10:1 for through holes and 0.75: 1 for microvias.
Drill to Copper
The drill to copper is the land clearance between the edge of a drilled hole to the nearest copper feature. The nearest copper feature can be a copper trace or any other active copper region. This is the deciding factor since even a small deviation will lead to cirucit disruption.
Minimum clearance = annular ring width + solder mask dam clearance
Classification of Holes
The drilled holes classified into Plated Holes (PTHs) and Non-Plated Holes (NPTHs).
The plated holes (PTHs) are the signal carrying conductive vias that establish interconnection. between the different layers in the PCB.
The non-plated holes (NPTHs) are non-conductive. These used to hold the components in position during the PCB assembly process. The component mounting holes are NPTHs. There is no tolerance level for these holes since the components won’t fit in if the hole size is too small or large.
A rule is a rule even for a hole
Non-Plated Through Hole (NPTH)
Finished hole size (mimimum)= 0.006″
Edge to edge clearance (from any other surface element) (minimum)= 0.005″
Plated Through Hole (PTH)
Finished hole size (Minimum) = 0.006″
Annular ring size (Minimum)= 0.004”
Edge to edge clearance (from any other surface element)(minimum) = 0.009″
After repeated usage, the drilling tools tend to wear and break. This leads to the following problems:
The accuracy of the hole location compromised:
When the drill bit fails to hit the preferred spot and shifts away in the same axis. The shifts in the drilled hole will give rise to tangency or breakout in annular rings.
Roughness inside the drilled hole:
Roughness leads to non-uniform plating of copper. This results in blow holes and barrel cracks. It can also result in lower insulation resistance. by penetration copper plating solution to the hole wall.
The resin in the board melts due to the heat generated during the drilling. This resin sticks to the hole walls and called as resin smear. This again results in poor copper plating. and leads to conductivity failure between the via and the interior layers of the circuit. The resin smear removed by a chemical solution.
Presence of entry and exit burrs:
Burr is the unwanted part of copper sticking out of the hole after the drilling process. They seen both on the top surface of highest stacked of printed circuit board. and on the bottom surface of lowest-stacked of the printed circuit board.
Exposed copper of inner layers on through holes. formed the shape of nail heading during drilling. Such a huge burden to hole brings non-uniform surface of through holes. and may cause conductivity failure of plating.
The partial separation of the PCB layers.
All these irregularities ruin the integrity of a PCB. These problems have been a nightmare for the PCB manufacturers. For these reasons our in-house PCB engineers whimsically define PCB as. “Problems Come Back!”
drill for pcb problem solution
To end these flaws. scholars have researched on drilling process and PCB design structure. and have come up with the following solutions:
It is a chemical process where the melted resin that deposited on the hole walls removed. This process eliminates unwanted resin and enhances electrical conductivity through the vias.
It is a motorized process that. eradicates the elevated ends (crowns) of the metal (copper) called burrs. Any debris that’s left out within the holes exterminated through deburring process. The desmearing process repeated after deburring.
Delamination can avoided by using laser drills. As mentioned earlier, in laser drilling, the workpiece. and the tool do not come under contact thus eliminating delamination.
In recent years, the drilling process has optimized compared to earlier technologies. With the exponential growth in the PCB industry. the drill precision is reaching close to perfection. now you have a better picture of how the PCB drilling process done. It looks quite complicated, isn’t it? Don’t worry! submit your design files (Gerber) to Sierra Circuits. Allow us to drill, while you sit back and watch Netflix and chill.
Take a look at the quick guidelines below which can help you save a few bucks.
Quick DFM Drill Validation Tips for PCB Designers:
The aspect ratio must kept minimum to avoid drill wear
The more number of different drill sizes that added. the more drill bits the manufacturer will need to use. Instead, if you reduce different drill sizes, the drill time will cut down.
For drill count / Size between Drill file and Fab print
If drill type defined (PTH / NPTH)
For close holes less than 0.006″ if yes it must addressed
If the drills and other features on copper layers are falling outside the board profile
If vias size should dropped to meet minimum Aspect ratio (A/R) need looking at drill tolerance
For Plated drill tolerance for less than +/- 0.002″ and NPT drill tolerance of +/- 0.001
Fab drawing for arcs showing NPT drill/slot or cutout locations but missing in the drill file