KiCad Overview and Schematic Tutorial

NOTE: This tutorial was written in 1847, and kicad has changed a lot since then!

The main KiCad project window:

The part of KiCad that may not be familiar to users of other CAD software is cvpcb. This assigns pcb footprints to components in the schematic. Unlike Eagle, where component libraries contain both schematic and footprint information, in KiCad the schematic version (symbols) of a component and its physical layout (“module”) are stored in completely different libraries, and must be mapped together with cvpcb. It’d be confusing, but you could map a resistor in the schematic to a capacitor’s footprint.

main kicad screen

The project file (.pro) contains preferences. For instance: component libraries that should be loaded with a project, trace width setting and drawing colors.

The main project window shows documentation files (like pdfs) as well as board and schematic files.

Making a Blinking LED with a 555 Timer:

Drawing the Schematic:

Open eeschema (the schematic editor) and click the tool that adds new parts.

add component in kicad eeschema

Click somewhere in the schematic to open the component selector.

kicad component selector

Now click “By Lib Browser” to see a list of all the libraries, their components and diagram previews. You can also type “*555*” (no quotes) and click “OK”, or type some keywords, like “audio” and click “Search KeyWords”. Not all components will have keywords, however.

kicad library browser

KiCad actually comes with a large set of pdf spec sheets that you can quickly access by clicking the documentation button.

 Click “Export to Schematic” to place the component.

Repeat the procedure to add a resistor, which is located in the “device” library and called “R”. You can also just type “R” in the “component selector” box.

kicad shift select copy

Make 2 copies of the resistor by holding down Shift and dragging a selection box over the resistor.

kicad rotate by pressing R

Now add a LED (also located in the device library), but before clicking to place it, hit “R” to rotate 90 degrees.

555 timer parts

Add a capacitor (C), polarized capacitor (CP) and Pot.

Finally, add power and ground connections by clicking the Add Power (“place the power”) button. add power connections You can also add power or ground connections using the Library Browser and normal Add Parts button–the Add Power button is a shortcut to the Power library.

add power in kicad add power in kicad add power in kicad

Add 9V and GND connectors.

Drawing Wires:

555 timer circuit in kicad

First, arrange the parts by hovering the mouse over them, and typing “M” or “R” to move or rotate.

Then select the Wire Drawing Tool. 

kicad connecting components

Note: you must start and end wires on the pins of components, it’s not enough that a wire visually connects with a component. For instance, if a wire is drawn between R1 and R3, R2 will not be connected.

erasing wires in kicad

Tip: To erase part of a wire, draw back over it.

connecting nets with labels

You can also connect nets and components by applying labels to wires. Just right click on a wire. Labels can be helpful for identifying traces when designing the pcb later on.

Where are the power and ground pins for the 555 chip?

show pins kicad

Clock “Show Pins” to see the hidden power pins.

hidden power pins kicad

Now you can see pin 1 and 8. Because they are marked as being power pins in the component library, KiCad automatically connects these pins to wires that have power pins labeled VCC and GND. Note: If your select a different power pin, say 9V+, the implied connection won’t work. You would have to unhide the hidden power pins and manually connect them.

Annotating Components (numbering… R? –> R1, R2, C1, U1, etc.):

annotating schematics in kicad

You need to number the components before moving on to the pcb layout. Click the Annotate Tool,  set the params, and kicad automatically numbers all the components.

annotating schematics in kicadannotating schematics in kicad

Adding values to components (10k, .01uF, etc.):

Just double click on the component to change its value.

 

 

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Tutorials for KiCad – A Free Open Source Schematic and PCB Layout Editor

NOTE: This tutorial was written in 1847, and kicad has changed a lot since then!

Intro:

kicad tutorial

This set of tutorials will cover some essentials to designing circuits and pcb layouts using kicad (link goes to author’s site + download), an open-source tool for circuit (board) design that’s free and has no restrictions on number of layers or size (like Eagle). We’ll focus more on the unintuitive things as well as tips & tricks rather than re-write the manual.

Contents:

Metal Working

Metal Working

Some basics of working with metal along with demonstrations of useful tools. Corrections and feedback appreciated…

Comments:

Dec 10 2007admin said:

Feedback and corrections are appreciated.

Jan 02 2008anonymous said:

A very infomative video for people getting started. I am a machinist myself and can agree with everything you said for hand drilling and tapping.

Jan 02 2008scott (admin) said:

Thanks. We talked with several machinists to make this, and there was some debate on how often reversing a tap was necessary. Any thoughts? Surely it depends on everything (metal, tap sharpness, cutting fluid, etc), but what do you do in general?

Jan 08 2008anonymous said:

Good videos! I just watched the soldering video before this one, and I have to say I’m very impressed with the accuracy of the information and the quality with which it’s presented.

Jan 11 2008anonymous said:
Hi Great videos mate, a good idea for filing aluminium is to first rub chalk into the teeth of the file, it embeds into the teeth and makes cleaning the file a whole lot easier,( and maybe stops you getting abused if you are using someone elses tools) This is probably the best site I’ve found for soldering advice , well sourced and professionally presented.Thankyou and regards
Gary
Jan 27 2008anonymous said:

Great video! Very useful. Thanks.

May 22 2008anonymous said:

I’m very impressed by your Metal Working video. Looking forward for your next online video’s on this subject!
Question: Do you ship to the Netherlands?

Keep up the good work!

Regards, Bjørn
bkeizer@gmail.com

flag
May 22 2008scott (admin) said:

yep, just follow the instructions on the check page. we can’t ship flux or batteries, though.

Sep 18 2008Daletone (unregistered) said:

You did a great job with this video. I am a machinist and have found everything you described to be very accurate and useful for the basics of drilling a hole.

The video has a lot of information for the beginner, but the beauty of online videos is that you can slow them down and watch them over and over. Keep up the excellent work!

Sep 18 2008scott (admin) said:

Wow, thanks!

Oct 05 2008Paul (unregistered) said:

To echo Daletone’s comments, I have been a machinist for 22 years and I am impressed with your metalworking video. Excellent job. I came here for your soldering information, so I imagine it is of the same quality.

Regarding reversing the tap: This is on the conservative side, especially for Al. But in the home shop environment it definitely pays to be conservative.

Thanks for a great site!

Jul 13 2009kayman (unregistered) said:

good stuff. highly recommended!

Tap Drill Sizes

Some explanation:

What kind of tap do I need? As explained in the screw guide, coarse threads are much more common, stronger, less likely to jam during installation (cross thread), and faster to install. So, if you’re deciding between coarse and fine threads for a custom hole, use a coarse thread unless you’re going into sheet metal. If you’re trying to make a hole for an unidentified screw, chances are it’s a coarse thread. Metric coarse threads are in between English coarse and fine threads. Metric fine threads are finer than English fine threads and are rarely used.

50% vs 75% tap drill sizes: 100% engagement of a male and female thread means that both threads are fully formed and fully engaged. 50% means that only half of the thread height is engaged, and is what you’d have if you ground off the top half of a fully formed thread. According to the machinery’s handbook, tests have shown that more than 60% thread engagement provides no significant increase in strength. For thread engagements more than 1.5 diameters deep, 50% is usually sufficient. Most taps drill are sized to drill a slightly larger hole than what a 100% thread could be cut into, typically 75% or 50%. More commonly, holes that will create a 75% thread when tapped are used as a margin of safety, and this is what we sell. The downside with drilling a hole that a 100% thread could be tapped into is that it is much more difficult to tap (deeper cuts into the metal), and therefore much more likely to break a tap. We recommend 75% tapping drills unless deep holes in steel are being made.

Clearance holes: A clearance hole is large enough for the screw to slide through without being turned. Many tapping charts will have two types of clearance drills: tight and loose. We list the tight clearance drills and recommend choosing whatever bit is handy and larger than the major diameter for larger clearances–just make sure the screw head or washer is larger. Note that if several holes are being made, the tight clearances don’t leave much room for misaligned holes.

Coarse Threads – English


tap size
(major dia. – threads / inch)
screw
major dia.
tap drill size
for 75% .dia
tap drill size
for 50% .dia
clearance drill
#0-80 0.060 3/64 (.0469) 55 (.0520) 50 (.0700)
#1-64 0.073 53 (.0595) 1/16 (.0625) 46 (.0810)
#2-56 0.086 50 (.0700) 49 (.0730) 41 (.0960)
#3-48 0.099 47 (.0785) 44 (.0860) 35 (.1100)
#4-40 0.112 43 (.0890) 41 (.0960) 30 (.1285)
#5-40 0.125 38 (.1015) 7/64 (.1094) 29 (.1360)
#6-32 0.138 36 (.1065) 32 (.1160) 25 (.1495)
#8-32 0.164 29 (.1360) 27 (.1440) 16 (.1770)
#10-24 0.190 25 (.1495) 20 (.1610) 7 (.2010)
#12-24 0.216 16 (.1770) 12 (.1890) 1 (.2280)
1/4-20 .2500 7 (.2010) 7/32 (.2188) H (.2660)
5/16-18 .3125 F (.2570) J (.2770) Q (.3320)
3/8-16 .3750 5/16 (.3125) Q (.3320) X (.3970)
7/16-14 .4375 U (.3680) 25/64 (.3906) 15/32 (.4687)
1/2-13 .5000 27/64 (.4219) 29/64 (.4531) 17/32 (.5312)
9/16-12 .5625 31/64 (.4844) 33/64 (.5156) 19/32 (.5938)
5/8-11 .6250 17/32 (.5312) 9/16 (.5625) 21/32 (.6562)
3/4-10 .7500 21/32 (.6562) 11/16 (.6875) 25/32 (.7812)
7/8-9 .8750 49/64 (.7656) 51/64 (.7969) 29/32 (.9062)
1″-8 1.000 7/8 (.8750) 59/64 (.9219) 1-1/32 (1.0313)
1 1/8-7 1.1250 63/64 (.9844) 1-1/32 (1.0313) 1-5/32 (1.1562)



Fine Threads – Metric

tap size major dia.
mm (inch)
tap drill (mm) tap drill
(inch)
clearance (mm) clearance inch (dec.)
M1.6×0.35 1.6 (.0630) 1.25 #55 1.8 #49
M2x0.4 2.0 (.0787) 1.60 #52 2.4 #41
M2.5×0.45 2.5 (.0984) 2.05 #46 2.9 #32
M3x.05 3.0 (.1181) 2.50 #39 3.4 #29
M3.5×0.6 3.5 (.1378) 2.90 #32 3.9 #23
M4x0.7 4.0 (.1575) 3.30 #30 4.5 #16
M5x0.8 5.0 (.1969) 4.20 #19 5.5 7/32
M6x1 6.0 (.2362) 5.0 #8 6.6 G
M8x1 8.0 (.3150) 7.0 J 9.0 T
M10x1.25 10.0 (.3937) 8.8 11/32 12.0 31/64
M12x1.25 12.0 (.4724) 10.8 27/64 14.0 35/64
M14x1.5 14.0 (.5512) 12.5 1/2 16.0 5/8
M16x1.5 16.0 (.6299) 14.5 37/64 18.0 45/64
M18x1.5 18.0 (.7087) 16.5 21/32 20.0 51/64
M20x1.5 20.0 (.7874) 18.5 47/64 22.0 7/8
M22x1.5 22.0 (.8661) 20.5 13/16 25.0 1
M24x2 24.0 (.9449) 22.0 7/8 27.0 1-5/64
M27x2 27.0 (1.0630) 25.0 1 30.0 1-3/16


Fine Threads – English

tap size
(major dia. – threads / inch)
screw
major dia.
tap drill size
for 75% .dia
tap drill size
for 50% .dia
clearance drill
#1-72 0.073 53 (.0595) 52 (.0635) 46 (.0810)
#2-64 0.086 50 (.0700) 48 (.0760) 41 (.0960)
#3-56 0.099 45 (.0820) 43 (.0890) 35 (.1100)
#4-48 0.112 42 (.0935) 40 (.0980) 30 (.1285)
#5-44 0.125 37 (.1040) 35 (.1100) 29 (.1360)
#6-40 0.138 33 (.1130) 31 (.1200) 25 (.1495)
#8-36 0.164 29 (.1360) 26 (.1470) 16 (.1770)
#10-32 0.190 21 (.1590) 18 (.1695) 7 (.2010)
#12-28 0.216 14 (.1820) 10 (.1935) 1 (.2280)
1/4-28 .2500 3 (.2130) 1 (.2280) H (.2660)
5/16-24 .3125 I (.2720) 9/32 (.2812) Q (.3320)
3/8-24 .3750 Q (.3320) S (.3480) X (.3970)
7/16-20 .4375 25/64 (.3906) 13/32 (.4062) 15/32 (.4687)
1/2-20 .5000 29/64 (.4531) 15/32 (.4688) 17/32 (.5312)
9/16-18 .5625 33/64 (.5156) 17/32 (.5312) 19/32 (.5938)
5/8-18 .6250 37/64 (.5781) 19/32 (.5938) 21/32 (.6562)
3/4-16 .7500 11/16 (.6875) 45/64 (.7031) 25/32 (.7812)
7/8-14 .8750 13/16 (.8125) 53/64 (.8281) 29/32 (.9062)
1″-12 1.000 15/16 (.9375) 61/64 (.9531) 1-1/32 (1.0313)
1 1/8-12 1.1250 1-3/64 (1.0469) 1-5/64 (1.0781) 1-5/32 (1.1562)



Coarse Threads – Metric


tap size major dia.
mm (inch)
tap drill (mm) tap drill
(inch)
clearance (mm) clearance inch (dec.)
M8x1.25 8.0 (.3150) 6.8 H 9.0 T
M10x1.5 10.0 (.3937) 8.5 R 12.0 31/64
M12x1.75 12.0 (.4724) 10.2 13/32 14.0 35/64
M14x2 14.0 (.5512) 12.0 15/32 16.0 5/8
M16x2 16.0 (.6299) 14.0 35/64 18.0 45/64
M18x2.5 18.0 (.7087) 15.5 39/64 20.0 51/64
M20x2.5 20.0 (.7874) 17.5 11/16 22.0 7/8
M22x2.5 22.0 (.8661) 19.5 49/64 25.0 1
M24x3 24.0 (.9449) 21.0 53/64 27.0 1-5/64
M27x3 27.0 (1.0630) 24.0 1 15/16 1-3/16

How to Solder Correctly – and Why

Video Overview:

The goal of this guide is to explain how to solder electronic components, and also provide some guidance on choosing tools and materials

Contents:

  1. Select a Soldering Iron
  2. What kind of solder (rosin cored, etc. lead-free)? What is flux and when is it necessary?
  3. Prepare the work – How and why to clean components, wire stripping and tinning guide
  4. Tin the tip – Tips for prolonging tip life, making soldering easier
  5. Heat and Solder the Joint – including closeup pics of the proper way to hold the iron against the work. Also, numerous good and bad joint pics.
  6. Cleanup – Do you really need to clean off flux residues?
  7. Protection – What is a conformal coating? Some applications encase electronics in solid epoxy…
  8. Desoldering – Illustrations showing how to use solder wick, a solder sucker, and an iron with a vacuum bulb. Plus a special surface mount removal tool and other tips for removing smt chips.
  9. References – There are hundreds of other great how-to guides and resources out there, here is a review and listing of some of those.

 

Other references and guides:

 

Related Products:

Comments:

Dec 10 2007admin said:

Feedback and corrections are greatly appreciated.

Dec 15 2007anonymous said:

I can only get the first half of the video to play

Dec 15 2007admin said:

sometimes the video can take a while to load—try reloading the page. A slightly lower resolution version of the how to solder video can be seen at YouTube.

Jan 09 2008anonymous said:

great vid, very helpful!

Jan 18 2008anonymous said:

Thank you for this video !!! Helped me out a lot !!! Really appreciate it !!

Jan 19 2008anonymous said:

I have always had trouble getting good solder joints and to get solder to adhere on wire. Thank You for a very informative easy to understand Video and Narration.

Jan 27 2008anonymous said:

cool!

Jan 28 2008anonymous said:

sigh Remember people that lead is still by far the worse problem here. It takes about 8-15 micrograms (micro, not a mistake and I’ve thoroughly checked that) ingested per day to cause “lead poisoning” in a 6-year old. That means at least “special education” for Timmy, and it’s comparably bad for adults on a /kg basis. Just be smart and use lead-free. It’s a no-brainer for those who know the facts involved.

Jan 28 2008anonymous said:

egads, I just watched the video. The way he is cleaning the solder tip, etc… When it’s sitting on a joint or used with prudence it’s one thing…. even intact solder will release lead oxide (a readily distributable powder) for a variety of reasons, and if you’re going to step on it, allow to oxidize under heat …. sand! Parts usually are pre-tinned with lead alloys. BAD IDEA…. look, using lead solder is a bad idea, okay. Don’t.

it’s illegal to use lead solder in plumbing, but the amount you’d get on your hands from doing these things here could be thousands of times what would leach out of solder joints into water you drink. True, I don’t know how much gets ingested from what’s on your hands, table feet floor, but we clearly have a problem here. It would be most interesting to try an experiment with an appropriate amount of bitrex on the surface of all the solder, and see if you notice how you end up ingesting it eventually – that would demonstrate how you cannot keep the lead in one place if you use it like this.
The hobbyist should be the last to use lead solder, and yet many in industry have already stopped. I’m not talking about “the environment”, I’m talking about not harming yourself and your household. Just think for a second the sort of concentrations we’re talking about in a landfill vs. your house. If having lead around matters in a landfill, it should matter in your house. Why am I writing this, apparently with some ulterior motive? Because I’ve seen how bad lead is, and I don’t want to have to put up with somebody else’s mess. Lead is so hard to clean up and easy to not put down, it’s time to grow up and start being a bit more responsible about it.
I hardly object to it’s use in SLA batteries for instance, but this is not it’s place.

Jan 28 2008scott (admin) said:

While it’s certainly a good idea to wash your hands after soldering with lead-based solder, I’m not convinced that there’s significant risk to using lead-based solder. Sure, ingesting small amounts can be harmful, but how likely is it that small amounts wil actually be ingested?

Lead-free solder has its risks, too….

This claims there is evidence that the fumes from lead-free solder are more harmful (just how much more harmful? not sure…)

The lead-free alternatives have environmental costs as well.

It would be interesting to find out just how much lead from hand-soldering becomes ingested on average. I suspect it’s not a harmful amount. Assembly line workers have been assembling equipment with lead-based solder for a couple decades now, and I haven’t been able to find any studies showing a harmful amount of ingestion, although there are many that discuss the asthma risks from the flux fumes. (see this OKi ad)

Some more food for thought: this
article claims that there have actually been no documented studies showing ground water contamination from lead in land-fills (the main impetus for RoHS and WEEE regulations). Apparently lead from electronics comprises less than 1% of lead used, the rest coming mainly from batteries and CRT monitors (although the disposal of these is much more controlled). Note, lead can in fact be leached from PCBs, so I’m definitely not arguing against the prudence of those regulations.

I’d be very grateful for links to studies showing documented cases of lead-poisoning from hand-soldering.

Feb 13 2008anonymous said:

excellent video – clear and to the point – great work.

Mar 05 2008anonymous said:

Thanks a million. That video is a huge help. Very well done.

Mar 05 2008anonymous said:

@scott: I’d highly suggest you watch Manufactured Landscape which has nothing to do with this except for one part where he goes to villages in China known for recycling electronics and noticed that you can smell the heavy metals from miles away and that the government now has to deliver water by truck as the natural sources are all contaminated.

Mar 05 2008scott (admin) said:

point taken 🙂 If you have a link to youtube that’d be great…

I wonder what all is being thrown into that particular village… a lot of lead is used in car batteries here in the States, but their recycling is very much controlled, so little battery lead ends up in land fills.

Sounds like that village missed out on China’s version of RoHS.

Mar 12 2008anonymous said:

why pronounce it “sawder”? Took me ages to work out what he was on about.

May 04 2008anonymous said:

same reason it’s spelled “could” and sounds like “kude”

May 19 2008anonymous said:

Outstanding video! I will be building a kit soon, and I found the information in the film will be of great help. Thanks so very much.

Dick Williams KB3OMJ

May 22 2008anonymous said:

A good tutorial. I’ve been soldering for over 20 years (professionally and hobbyist), but it’s always good to brush up on techniques.

May 22 2008scott (admin) said:

thanks… we’d love to hear any critiques you have or better ways of doing things that you’ve picked up over the years.

May 22 2008anonymous said:

In further answer to the March 12, 2008 question “why pronounce it “sawder”? Took me ages to work out what he was on about,” please note that the questioner is not a native American english speaker, but rather a United Kingdom native speaker, wherever he/she actually resides. The North American pronunciation of “solder” is indeed “sawder.” But I would also point out that the phrase “he was on about” is equally obscure on this continent. It is not used here, except by those trying to emulate usage in Great Britain and its commonwealth. I would suggest that the original poster not be so critical, particularly while revealing his own linguistic shortcomings and lack of exposure to the usages of English around the world. The other commentator was a bit more cryptic, if more humorous than I, when he said “same reason it’s spelled “could” and sounds like “kude”. And finally, no less a personage than Sir Winston Churchill said something to the effect that “the UK & USA were two countries divided by the same language.” It was a good joke when he said it, and all the more so because it was so true, both then and now.

Now on to more important things. After all that, I will add that I thought the video was very well done, and will recommend it to a number of people with whom I work who will profit a great deal by it. I have been occasionally soldering electronic components for over 55 years now, and while I can recognize both bad and good solder joints, I have not been able to convey that knowledge to those 1/3 my age in nearly so clear a form as this video. Good work, and many thanks.

May 22 2008scott (admin) said:

thanks!

May 23 2008anonymous said:

And now for something completely different.

The online etymological dictionary says:

https://www.etymonline.com/index.php?term=solder

As for the snippish comment about “could”:

https://www.etymonline.com/index.php?term=could

Jun 14 2008anon (unregistered) said:

Great Video! I’m just starting to get into some of this for repairing/modding old video game systems, to make them into musical devices and this gives me hope that with time I can start to understand the process enough not to mess it up.

Jun 14 2008anon (unregistered) said:

I just broke the piece of metal on my glasses that connects the two lenses together and I was wondering if that was something that would be able to be soldered? I also have a 1 year old that loves grabbing at them so I would assume lead based solder wire would not be a good idea, any advice?

Sep 03 2008Kusanagi (unregistered) said:

Hey, does anyone know what solder and devices would be needed for a newbie to desolder and resolder the audio wires for a nintendo ds lite??

I need it for no other purpose than that

Sep 03 2008scott (admin) said:

please post questions in our soldering forum

thanks!

Oct 11 2008Trevor (unregistered) said:

wow everything you said not to do I’ve done so this video is GREATLY apprieciated thank you!!!

Jan 06 2009Jb (unregistered) said:

This must be the best Tut Vid i have seen online !!

Jan 06 2009Mikk (unregistered) said:

Tip requires sanding as the solder alloys with the copper of the tip forming brass. Brass has different solderability (wettability + thermal conductivity) than original high copper tip. Section a tip and metallographically prepare and etch it and it is readily apparant we are dealing with two metallurgically distinct regions. Sanding (grinding) is the solution .. excessive tinning might be the problem (along with excessive heat) under no-load conditions.

Spock out!

Jan 08 2009Gary, KE7FIZ, PE, CID+ (unregistered) said:

Very good vid. I especially like how you show bad examples, as well as good – that’s missing from other training videos I’ve seen.

And thanks too for tempering the OMG-Lead-We’re-Gonna-Die hysteria. Good links and rational info provided on the subject. I searched once trying to find the vapor pressure of lead at soldering temperatures. No luck except for one paper that had measured it at higher temps and extrapolated the result to soldering temps, describing it as: ‘a really hard vacuum’. The only other thing I’ve found are reports of no elevated blood levels of lead in electronics workers after years of ‘exposure’.

I’ve also read of the poor children in the contaminated ‘recycling villages’ in China (and elsewhere). If they weren’t being exposed to the tiny bit of lead in electronics, they will certainly be exposed to the much greater amount of lead in CRT’s and batteries. It’s all done illegally anyway, and if it’s not lead it’ll be something else that’s toxic, illegal, and profitable, that someone will use to expolit people at that level in that type of society. Removing lead in electronics is “not” a solution to that problem.

Feb 26 2009Mike (unregistered) said:

Thanks for the video. I’ve done a little electronics soldering here and there over the last 20 years or so, and I’ve honestly never really had a clue what I was doing. This video was much more helpful than reading about it in a book.

Apr 13 2009Jordan (unregistered) said:

Thanks a lot, this was a great help, I had done larger scale stuff, like pipes, but that’s a total different ball game.

Sep 12 2009gail (unregistered) said:

Very good, just one suggestion: speak a little slower. Thank you!

Sep 12 2009Van Bever Koen (unregistered) said:

great tutorial for someone who knows nothing from soldering

Sep 23 2009bacteria (unregistered) said:

Excellent guide! Very useful.

Dec 27 2009daniel [mex] (unregistered) said:

i hoped to see this video moths ago, i reallly did a mess in my pcb projects, so now that i know how soldering, i will try hard to make a better work, thanks a lot ^^

Jan 04 2010Tom Luque (unregistered) said:

I have done NASA certified soldering, and you have shown excellent views of good and bad joints. We used soft erasers to clean board pads and componant leads. Gold pads were more difficult to achieve a good shiny flow.

Apr 04 2010Marcus (unregistered) said:

Great video, it’s all more clear now 🙂 Thank you.

Apr 05 2010Tom (unregistered) said:

This is the best how to solder video I’ve seen yet, and I’ve been looking at many. You explained the technique as well as the chemistry behind the process, and had good repetitive video samples. I had never heard of the heat bridge and soldering from the opposite side of the wire. Thanks a billion!

Drill Speeds

How to choose the right drill speed

Quick Summary: Some approximate starting advice is to set the spindle speed between 700-1000 rpms for steel, above 2000 for aluminum, and slow down from there if you get discolored chips or heavy drill bit wear. In most cases the drill press will not be able to supply enough power or speed to follow the below recommendations. A 3/8″ drill bit drilling mild steel at the recommended speed and feed could require around 1 hp. Going slower usually doesn’t hurt, and will prolong tool life.

Drill press spindle speeds depend on lots of things: the type of material being drilled and its hardness, the hole size, the type / hardness of the drill bit and its sharpness, whether or not a cutting / cooling fluid is used, and the rigidity of the drill and clamp, among others. Also, most speed recommendations are geared towards manufacturing environments where machining time is very expensive. As drilling speed increases productivity goes up, but tooling also wears out faster. The recommendations seek a balance between these two concerns, but this balance is not determined with the pocketbook of someone running a hobbyist or prototype shop in mind.

So, for the hobbyists shop, where longer tool life is probably more important than machining time, and where pushing the speed limit may ruin a valuable prototype, reasonable advice might be to start off at about 75% of the recommended drilling speeds. The “First Guesses” below are already a little slower.

You’ll typically see large ranges of recommended speeds for various materials, and some discrepancy between different sources. This is partly due to the large influence the material hardness has on how fast it can be drilled (harder –> slower). Even if the material and its hardness were precisely known, the large number of other factors would require some experimentation. If the chips are smoking, turning brown, or the outer edge of the drill bit is chipping, go slower or add some cutting oil / coolant. (a decent guide to cutting fluid)

In general, a slower-than-recommended spindle speed won’t hurt anything except in the case of extremely small drill bits, say smaller than 1/16″. With small bits, it’s hard to feel resistance from the metal, and therefore, very easy to push down faster than they can remove metal. Using recommended RPMs (spindle rotation speed) mitigates this risk. A tip for drilling extremely small holes is to drill down to the depth stop, and then move it down a 16th of an inch, and repeat. This ensures that too much metal isn’t chewed off too quickly.

 

Feed Rate: This is how fast the drill bit is pushed down. For reference, the recommended rates go from .001″ per revolution for bits under 1/8th” to .007″ per revolution for 1/2 bits. This, of course, isn’t very useful if you’re lowering the drill bit by hand. In general, push hard enough to create a continuous chip (note some materials just won’t form one–like cast iron), but not so hard that the chips are turning brown or the bit itself is chipping. Slight discoloration of the chips is OK. Don’t push as hard right when the bit is about to break through, this will reduce the likelihood of it grabbing and tearing the metal.

Surface Feet per Minute (SFM): Speed recommendations are usually given in SFM, which is the speed a cutter can be pushed in a straight line. On drill bits, the fastest cutting rate is at the circumference, and its rate of travel is equal to the RPM (Revolutions Per Minute) of the bit times the circumference (pi*Diameter). So, the translation between SFM and the RPM speed of a drill bit is:

Rotation Speed (RPMs) = (3.82) * SFM / Dia.          SFM = (.26) * RPM * dia.



Material Speed
Range (SFM)
First
Guess (SFM)
RPM recommendations based on First Guess Speeds
for various drill bit diameters
1/8 (.125″); 1/4 (.25″) 5/16 (.3125″) 3/8 (.375″) 7/16 (.4375″) 1/2 (.5″)
low carbon steel, up
to 275 Brinnel hardness
60-100 100 3056 1528 1222 1019 873 764
high carbon / alloy
steel, up to 275
Brinnel hardness
55-85 50 1528 764 611 509 437 382
tool steel 45-60 50 1528 764 611 509 437 382
cast Iron 50-125 70 2139 1070 856 713 611 535
aluminum and alloys 200-300 250 7639 3820 3056 2546 2183 1910
brass / bronze
high strength bronze may
require 70 or less
150-300 200 6112 3056 2445 2037 1746 1528
wood 300-400 300 9167 4584 3667 3056 2619 2292

Some considerations for using the above table:

    • First, note that the speed recommendations for small bits in aluminum are ridiculously high compared to the max speed of around 3000 RPMs on bench-top drill presses. These numbers are more just for reference, it’s fine to go slower, just don’t push too hard on the small bits.
    • “First Guesses” are based on more typical materials and hardnesses.
    • If the material has been hardened, the recommended speed will be substantially lower. If the hardness is above 300 Brinnel, starting at 20-30 SFM isn’t a bad idea.
    • Note that these values are recommended for HSS (High Speed Steel) drill bits, not carbon steel ones. HSS gets its name because it is able to maintain a reasonably hard cutting edge even while it is red hot. If you’re using carbon steel drill bits (unlikely), cut the recommendations in half. If you’re using carbide tool bits, up the speeds by 2 to 3 times.
    • Adding cooling / cutting fluid may allow speed increases, too, and should be used in any case on steels. Cutting fluid will almost always increase the quality of the cut.
    • If the hole is more than 3 diameters deep, consider drill as much as twice as slow since it will be much harder for heat to escape.
    • Other site’s speed recommendation tables (note the differing opinions!): here | most comprehensive | Wilton drill press instruction guide (very good)




Comments:

Jan 03 2009onerustycar said:

Yeah, I would say that would be the best “chart” as it were. Once anyone has broken or smoked a half dozen drill bits you start to get the feel for it. At two dozen you’re a pro!

Jan 03 2009scott (admin) said:

🙂

Mar 30 2010Geoff (unregistered) said:

I thought the information was great…. I tied a few of the settings, including tool steel and mild, and they all worked great…. many thanks !!

about 13 hours agoAlex (unregistered) said:

Hi, i have a wickes 250w pillar drill i need to know how to increase the speed of the drill so i can use it for cutting mortices unfortunately i have mislaid the instruction book if any one knows then that would be great thank you in advance for your reply.

https://www.drill-press.org/drillspressstands.html

Finally, make sure the machine is spinning the right direction. Mills are often left in reverse…

Decimal Sizes for Numbered and Lettered Drills

Drill Number / Decimal Cross Reference

drill number decimal (inch) decimal (mm)
97 .0059 .150
96 .0063 .160
95 .0067 .170
94 .0071 .180
93 .0075 .190
92 .0079 .200
91 .0083 .211
90 .0087 .221
89 .0091 .231
88 .0095 .241
87 .0100 .254
86 .0105 .267
85 .0110 .280
84 .0115 .292
83 .0120 .305
82 .0125 .318
81 .0130 .330
80 .0135 .343
79 .0145 .368
78 .0160 .406
77 .0180 .457
76 .0200 .508
75 .0210 .533
74 .0225 .572
73 .0240 .610
72 .0250 .635
71 .0260 .660
70 .0280 .711
69 .0292 .742
68 .0310 .787
67 .0320 .813
66 .0330 .838
65 .0350 .889
64 .0360 .914
63 .0370 .940
62 .0380 .965
61 .0390 .991
60 .0400 1.016
59 .0410 1.041
58 .0420 1.067
57 .0430 1.092
56 .0465 1.181
55 .0520 1.321
54 .0550 1.397
53 .0595 1.511
52 .0635 1.613
51 .0670 1.702
50 .0700 1.778
49 .0730 1.854
48 .0760 1.930
47 .0785 1.994
46 .0810 2.057
45 .0820 2.083
44 .0860 2.184
43 .0890 2.261
42 .0935 2.375
41 .0960 2.438
40 .0980 2.489
39 .0995 2.527
38 .1015 2.578
37 .1040 2.642
36 .1065 2.705
35 .1100 2.794
34 .1110 2.819
33 .1130 2.870
32 .1160 2.946
31 .1200 3.048
30 .1285 3.264
29 .1360 3.454
28 .1405 3.569
27 .1440 3.658
26 .1470 3.734
25 .1495 3.797
24 .1520 3.861
23 .1540 3.912
22 .1570 3.988
21 .1590 4.039
20 .1610 4.089
19 .1660 4.216
18 .1695 4.305
17 .1730 4.394
16 .1770 4.496
15 .1800 4.572
14 .1820 4.623
13 .1850 4.700
12 .1890 4.800
11 .1910 4.851
10 .1935 4.915
9 .1960 4.978
8 .1990 5.054
7 .2010 5.105
6 .2040 5.182
5 .2055 5.220
4 .2090 5.309
3 .2130 5.410
2 .2210 5.613
1 .2280 5.791

Drill Letter / Decimal Cross Reference

drill letter decimal (inch) decimal (mm)
A .2340 5.944
B .2380 6.045
C .242 6.147
D .2460 6.248
E .2500 6.350
F .2570 6.528
G .2610 6.629
H .2660 6.756
I .2720 6.909
J .2770 7.036
K .2810 7.137
L .2900 7.366
M .2950 7.493
N .3020 7.671
O .3160 8.026
P .3230 8.204
Q .3320 8.433
R .3390 8.611
S .3480 8.839
T .3580 9.093
U .3680 9.347
V .3770 9.576
W .3860 9.804
X .3970 10.084
Y .4040 10.262
Z .4130 10.490
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