Rack for backpacks

A couple weeks ago Lady of the House asked me to do something to all those backpacks hanging on the floor and corners. Naturally I took the challenge and started to make plans and specs with her. The goal was set:

1. Be able to carry 3 medium sized backpacks, fully loaded with books.

2. Looks nice.

3. Stays on the wall.

The starting point was a pine board. I cut it to lenght and drilled some through-holes to it. I also did three round pockets on rear side of the board. It also got some paint to match the wall it was going to.

When woodworking was settled, it was time to fire the lathe up.

Since I do not have pictures from the first rack, here are some from the second one.

 I ordered some hooks from that Swedish four-letter international furniture brand, only to find out that support mechanism inside that hook was plastic. 

That black thing in the middle of those shiny metal parts.

Before they arrived I planned to turn some aluminum plates to support those hooks. When the plastic was found it was only the matter of some more turning. I ended up using only the cap from the original hooks. 

I turned plates under the hooks and to backside of board. 

I drilled a hole on that plate going to backside to keep it from turning if tightning bolt get loose. I made a midsection part which actually holds the load. It was turned to lenght, threaded, and drilled from steel. Because of the set parameters I could not find standard bolt to fit inside midsection. Lathe solved that problem. That bolt holds everything together. It goes through midsection, support plate and pine board straight to the backplate which threads holds it in position. Bolt can be tightened up with an allen key. Midsection has an shoulder which keep the bolt from slipping through. The cap can be rotated in place when other parts of the hook are assembled.

When all parts was done, it was time to assemble the rack and attach it to the wall. 

The end product was actually so good that I received another order, this time a little shorter one and a different colour. 

As of writing this it is not on the wall yet, but it is ready to go.
(This blog text was created with a mobile phone application and boy, I feel that it killed all that small amount of smoothness of writing I may have had..)

Putting Some Smartness Into A Smart Fortwo

I have been a happy owner of a 2006 700cc Smart Fortwo since last Summer. But I have been want to put some automation to it for a while. I started my endeavor to making windows open even when ignition is off. There is easy to  follow instruction on the net.

I plan to have a spesific feature which for example a coupe BMW has. When door is opened, door window automatically lowers a bit and when closing the door, window goes automatically up. I want it because every time I close the door I feel overpressure in the cabin. It seems there is no pressure relieve valve like in more ordinary cars. Windshield is the biggest window in the car and because overpressure the sealing of it get much stress when closing doors. A very common problem with Smart Fortwo is a leaking winshield. My car had it also. I think that leaking is caused by overpressure. Luckily I managed to find leakage before my control unit got wet. By the way, that control unit controls pretty much everything in this car so it really should stay dry. It is located below dashboard so it easily get wet if windshield leaks.

That window feature is not implemented yet but I have made some testing. Maybe I’ll write something about it when it is done.

At the moment I just finished a very early alpha version of the control of seat heating. A small microcontroller(Arduino) controls with relays contact pads of seat heater switches. It puts them on automatically when head lights are switched on. After 30 seconds it puts them off and they stays off until lights are cycled off and on again. Convenient! Heating time is short because heating element is so powerful.

As I want more, I equipped control system with a rotary encoder, a temperature sensor and an LCD. My plan is that user can control various variables in the system, for example heating time. And of course temperature depended heating. When environment is warm enough one do not want his/hers seat to be heatened! LCD can display temperature readings and/or how much heating time is left.

Here are some pics taken during the process:

The initial plan was to install everything here.


Started to work by removing the Safety Triangle and dissassembling it.


The journey continues by re-engineering.


The very first version of connection board.


Here one can see it from another side. I planned to use PC817 optocouplers for isolation but along the way I switched to relays. More on that later. I took the liberty to use USB-connector for connection with car’s electric system. D9 is for rotary encoder.


This is a starting point for house making to rotary encoder. Black case is from an old wall charger for Nokia mobile phone. Knob is from an old car stereo or something like that.


Here is a rotary encoder soldered in place. When I was continuing this build I realized that I should have put rotary the other way around, three legs pointing to left instead what it is now. Well, it happens to all of us..


I also had to install capacitors to reduce interference. It still needs something, readings are not reliable enough.


There is something in the mess, I rarely see a workbench which is tidy and clean. Hmm, except Quin Dunki’s bench. Her work is amazing.

Anyway, some progress has achieved.


This is my power supply. In it’s early life it served as 12V mobile phone charger. Through this I can safely use my small embedded systems in electrycally noisy car environment.


This is my new connection board equipped with relays. As mentioned, previous plan was to use optocouplers. I did not managet to get them work, maybe because of some my stupid coding error. Anyway, I switched to relays.

Those relays “push” the triangle’s buttons when commanded by Arduino. Smart has conveniently system I like very much: Pushbutton is ON-OFF state information for car’s computer instead of some resistance change. This way relays can be used to “push” buttons.

From left to right connectors are: Black: Temperature probe connection, USB: Power to my system and controlling buttons and D9 is for rotary as earlier mentioned. Temperature connector in salvaged from an old PC’s motherboard. It is an audio connector. In the future there might be coming a minor problem with D9. In the end of cable is a quite heavy connector and stiff car’s suspension combined with that weight might do some issues by removing solder joints during time. That is to be seen.


This is a starting point for facade. The white plate is salvaged from an old laptop LCD monitor.


And here we are: Casing for encoder is ready, temperature sensor(red thing) is ready, main unit is ready. Now it only needs to be installed. And it maybe need some clever programming also. Now it is only a timer ) :


This is only temporarily mock-up.


From another angle. When thinking how to install main unit on top of dashboard wisely(read: do not drill holes in that dashboard) I got an idea: Why not make a console in front of gear stick and stuff the whole system inside it? That way there is room for that earlier mentioned window-control also.

Yes, that is a good idea. But then again that means a lot of work and no automated seat heaters yet. And Summer is coming. Also, I finally want to enjoy the work of my hands. It has been a long building process. What to do? Naturally install the system. Temporarily, of course. ūüėČ

Encoder is located beside the gear stick. Temperature sensor is on the floor, for now. Wires needs to be sorted. But it works. Hooray!


Here is a link for video

That’s all for now!





Servicing an Child’s Electric Piano

Recently we were given a small toy piano. Grandmother has bought it from the flea market. It is a very common cheap toy. Somewhere during the road it has had some bumps because half of the keys did not produce any sound at all.

Open it I did.. And it revealed it’s secrets to me. A piece of circuit board was missing, actually the whole board was cut in half. Luckily I managed to find that missing piece.



After some thoughts it was clear what to next. I inserted some cyanoacrylate and then I could go repairing those broken lines. I had to remove some coating that solder could stay in place.


Then some soldering and it looked like this:


When reassembly was done I recognised that it works!


Honda Quad Starter Motor Repair


A friend of mine has a Honda quad. He told me that it’s starter motor has gave up a ghost. Naturally I had to crack it open. During dissassembly process turned out that my buddy had rolled the quad upside down a couple of times which explains the motor oil inside of starter motor. After some cleaning it was okay, except brushes which were totaled.


Especially the another one. It looks like there has been some sparkling if I interpreter those craters right. 20160302_005-craters

My friend ordered the spare parts and a couple of days later them arrived.


During the assembly process we cleaned the anchor’s contact pads with sandpaper and a cordless drill. Not worthwhile compare to the lathe, but with limited resourses one must do what is doable..


Of course test drive went south. At first it started and ran fine, but during the second flight it stopped and did not started at all. No power, no nothing.  A closer inspection told me that somebody forgot to connect the ground wire to the motor. After reconnecting the quad ran fine and we back in business. Hooray!

Golf IV Brake Pedal Switch

I have a -06 Golf IV Variant and in one day it lit some warning lights to my instrument cluster.


EPC and¬†Engine warning light¬†lit and cruise control¬†not working. Naturally I fired Google up and found that broken¬†brake pedal switch can cause all of those problems. Running Ross Tech’s VCDS’s¬†Measuring Values for cruise control¬†confirmed the case. As one may know, cruise control needs to know when brake pedal is pressed that you don’t fight the engine. In the link provided is info how to check (with appropriate¬†cable and downloaded VCDS-software) if the brake pedal switch is faulty or not. When I checked mine, it turned out that one of the two switches inside that brake pedal switch did not work. So I¬†went to¬†a local dealer and bought a new one for 20‚ā¨. After fitting that in place I cleared all the DTC’s with VCDS and measured values again. All passed!

Some pictures of the process.

Here is the old one in position.


To remove it, it has to be twisted counter clockwise a bit.


Then it can be removed.


Empty space.


In hands.





A new one.




VCDS: No braking.


Braking. When braking, last two digits in Bin Bits-section must be 1, as they are now.


Happy driving!


I made a little cutters for cutting in half all kind of tablets. These are made of 3mm stainless steel sheet. Design is quite rough but I like them that way. They are meant to be in everyday use, so scratches are inevitable.

This is where I started, a sheet of metal and a freehand drawing.


I welded two plates together with mig.


The drilling has started. I was going to make this with freehand.


After some cutting.




Things are getting in shape.


After that I milled slots to avoid misalignment. I milled only 1mm deep and bent the rest of halves. Since fitting halves to the milling machine was a bit difficult, I had to use a file also.


Here we are getting some rough shape.


I cut the blades to correct length and sharpened the other blade. From a drawing you can tell that I forgot to make that little curve that keep spring in position. But no worries, I got it in the other route.


Since then I changed to a softer spring, made some guardian rails for it and put a new bolt for keeping halves together.

And polished them too.



And that’s it!




A New Toy

I have got my hands on a new toy. A dividing head.


But it lacks a tool for tightening objects in to the chuck. So we need to make one.

I took a 22mm diameter shaft and measured that square hole has a 10mm side. So I need to take 6mm off from each four side of  the shaft. Chuck has a wheel of 36 teeth and one can lock those teeth in position, one at the time. A quick calculation gives that when the first side is milled down 6mm, 18th teeth must be locked in and then milling can continue. After that 9th teeth locked and milled. And the last 18th teeth and milled. (Of course this can be done by 9 teeth at a time.)

Her we are in the middle of the process.


When all sides was milled, I bored a 13mm hole to the shaft. At first I used a center drill bit and a lubricant and then I gradually moved from 6mm to the big one.


All I have to do is to cut those¬†22mm and 13mm shafts in convenient length and make some adjustments that 13mm shaft don’t¬†slide through the hole in 22mm shaft. And of course to do some grinding.¬†Shafts¬†are just some ordinary steel (st52 or something like that) so I am not expecting them to last¬†too long, but time will tell that.¬†On the other hand, I don’t believe that this dividing head (and its new tool) is going to get too much attention in its current location. Conveniently other chucks around the shop uses a different size of a square tool.


Here is the Machine behind all of this..


And no, I don’t own it, I just can borrow it and facilities around it.

Remember to use at least safety goggles (and¬†Colin’s safety tie ūüėČ ) when using metal working machines!