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Attention Europeans: SIEG Scandinavia

I was looking for information and dealers for the SIEG CNC series and came across a very low price dealer in Europe called SIEG Scandinavia. They offer on their website the whole SIEG production machines and at a very low price compared to for example Finnish dealers.

On some machines there is free shipping in European Union, but generally the DHL cost is 120 EUR per machine, which is very reasonable.

I haven't yet bought anything from them, as I'm collecting money for the SIEG KX3-CNC machine with a Mach3 software.

Changing mains plug

The SIEG C4 lathe that I bought from Axminster Tool Centre works on 230 VAC 50 Hz mains voltage, the same we have here in Finland. The only problem was that the power plug in the end of the cord was some British type and not the kind of we use. So I went to the local hardware store and bought a plug that is made of rubber, rated for 16A and has an insulation class IP44. The cost of the plug was 1.79 EUR, so it is cheap.

I don't know of other countries laws on electrical work, but here everybody has the right to change a power cord to a device. Technically I'm not changing the cord but in reality I'm doing the very same end result with the same connections so it doesn't count.

First thing to do was to cut the original British plug and toss it. At the same time I stripped the insulation down about 40 mm and clipped the neutral and live wire about 5-10 mm shorter than the grounding wire. This is made so that if you yank the cord and the wires get ripped off, the ground connection is the last one to rip off and in some cases it can save your life. In this plug it doesn't matter that much, but I have a habit of doing this always so I don't forget it.

I stripped the insulation off of the ends of the leads for about 5 mm and twisted the stranded wire together. Using a screwdriver I opened the new plug and screwed off the strain relief.



First I opened the screw for the grounding wire (green-yellow) and put it under the screw and tightened. After that I bent the live (brown) and neutral (blue) to their attachment points and screwed them tightly. This plug type is non-polarised, so it doesn't matter which way you attach the live and neutral. Last I screwed the strain relief tightly so it clamps on the black insulation of the cord.

Pulled the cover on and screwed it snug and this modification is done.

What I do for living

Some have asked what I do for living or what is my profession. At the very moment I'm still in college, but I'm getting my degree in tool & die making in 3 months. Tool & die maker is basically like a machinist, but it is more to do with jigs, fixtures, molds, dies and tools. And generally speaking tool & die work is not a job where you make a hundred of this and a million of that, but rather one of this and two of that.

I already concluded all my obligatory training and exams, so I'm basically waiting for the graduation event and using this time to be at a moldshop to earn some living money. In this same place (Työkalutyöt Mattila Oy) where I work I did my thesis work, which was a very basic permanent casting mold for aluminum. The photo on the right shows the mold installed in the casting machine. This PDF (17 MB) descripes the work with lots of pictures, but unfortunately it is only in Finnish at the moment. I'm planning on writing it in English once I learn what the different mold parts are called in English as I don't know them all.

I have had extensive training in school about plastic injection molds, but at the company I work we mainly do die casting molds. They work essentially the same but have much more work and things to consider as the mold fills up with liquid aluminum rather than liquid plastic.

I'm more specialised in assembling the mold, which means finishing all the pieces, fitting them together, assembling everything and making the small pieces that are missing with (usually) a manual lathe and a surface grinder. I also do mold polishing and fitting the whole mold after assembling it.

And when the need arises, I use the CNC mills with MasterCAM or straight from the Heidenhain controller panel to make parts. I mainly use 3-axis mills, but I have had some limited training on 3+2 axis work on a 5-axis machine.

We don't have a wire EDM, but I do know how to operate one as I have used Fanuc 0iA and 1iC machines. Sinker EDM experience is a little bit less than my wire EDM experience, I have only used an AGIE-Charmilles and repaired an old AGIE (older than me!). The one pictured on the right is the machine we had in school.


We also do not have a CNC lathe, but I have used one small machine at school (picture on the right) extensively, as I was the only one who knew how to operate it. Nobody had a clue of how to run it, so I did as I always do: RTFM. In the course of learning to use the machine I wrote a manual for the lathe in Finnish with lots of pictures. The lathe controller was Fanuc 0-TD, meaning very old and very basic.

Stand for the blasting cabinet

I also made a stand for the blasting cabinet to get a comfortable working position. This is the reason for the elbow connector in the air line, so that it doesn't take room but goes down, as my workspace is very limited and getting pretty crowded with all the various stuff.

I welded the stand from 25 x 25 x 2 square steel tube, better known as "furniture tube" in here. I used a MIG welder because that was available and it is quick to use. I got the material from Rautasoini and it cost me about 20 EUR for the 9.6 meters of material and a cutting fee of 1.7 EUR, so quite cheap.

For welding the frame nice and square I bought a magnetic square from Biltema for 5.49 €. It provides 30 kg of magnetic pull and the 105 mm side length provides accuracy. I tested this little gadgets accuracy with a 400 mm machinist square and the magnetic square was truly a square. In retrospect I should have bought two or three of these to make the setups even more easy, but even with only one I could free my hands and got rid off of using clamps and got everything square in one go.

Once I had welded the frame I checked the diagonal lengths and found that there was 1 mm difference in 900 mm distance, so it was really good. The frame was a little bit twisted, as it rocked on the floor a little, but I fixed this by grinding about 0.5-1 mm off from one of the legs. This way the blasting cabinet sits on the stand without rocking during use. The floor side of the frame doesn't matter as the stand will have adjustable feet.

I used an air powered angle grinder to smooth the welds in all corners and then an angle sander on all surfaces to break the shiny metal so the paint sticks better. I wiped all the grinding dust with a rag and then used a clean rag and solvent to go through all surfaces to remove the last bits of dust and all the oil.

I had bought red oxide primer and black matte spray cans from Biltema for a total cost of about 10 EUR. I sprayed the primer on the frame in thin layers and with a help of a flashlight I inspected every surface that there were no metal to see and that the primer was smooth. I let the primer dry for half an hour and wiped the surfaces with a clean rag to remove the primer dust. I applied the black paint also in thin layers to get an even result, but run out of paint once I had the first layer, so I went and bought a second can of paint. This got me approximately two layers of paint and even surface, so good enough for me. I let the paint dry for two hours.

To give the stand good stability and finish I bought four plastic caps that were intended for this type of tube and had M10 nuts molded in them, so I could screw in the adjustable legs. The upper ends of the tubes I sealed off with similar end caps. All the caps I just whacked in with a rubber mallet and they fit snugly.

Once I got the stand home, I moved it to the correct place, adjusted the feet for level and stability and lifted the blasting cabinet on top of the stand. Fit as it should, with about 2 mm of free space from the tubes to the corners of the blasting cabinet.

Last bit to get this stand finished is to buy a piece of film faced plywood, cut the corners and install it on the supports I welded halfway up the stand to act as a storage space.

Blasting cabinet mods

Here is my blasting cabinet in operational condition albeit still on the floor in this picture. The small rectangular box contains about a litre of pantyhose filtered glass beads ready for use in the small blasting pen. The blasting pen is the one with the long and colorful hose in the middle and it has a small cup that holds the blasting media.

The original blasting gun was supposed to be installed with a small female connector in the right hand side panel so that there would be a G 1/4" female thread for a pipe connector. But as I'm not going to use the original gun but the blasting pen and I want a small air gun in there also for cleaning, I made a small splitter block from aluminum. The splitter block has two female quick connectors to attach the pen and the gun. The splitter has G 1/4" threads for the quick connectors and one cross drilling that I plugged from the end with an R 1/4" plug and pipe connection glue.

The air gun is from Biltema and provides very good adjustability as the trigger lever is long. It also happened to have the dangling hook in an otimal place just by coincidence, as I found out that it fits perfectly loose to the M4 screw that holds the air filter in the cabinet and is in reach of my hand while working. The hose for this air gun I liberated from the original blasting gun as it is quite thin walled and very flexible, so it is easy to maneuver inside the cabinet.

The inlet to the splitter block comes from the compressor with a hose that has a female quick connector in the end that fits a male quick connector. This is attached to an elbow joint that is going through the cabinet wall to the splitter block and keeping it also in place. The elbow connection saves me some lateral room as it comes out only about 30 mm from the side of the cabinet versus about 100 mm that it would take with the quick connector & hose coming in horizontally.

Blasting cabinet

I bought a blasting cabinet from Biltema (article #15-377) for 159 EUR. The cabinet is quite small so it fits my workshop well, as it is more than enough in size for my parts. My intention is to use this with the silent air compressor I built earlier, but I'm going to use a small blasting pen with this cabinet to keep the air consumption low. My blasting media will be fine glass beads as I want to have a nice finished surface on my parts and one lock related project needs this also.

And as with all things that I carry home, it happened once again. I get the box inside, close the door and turn around and the Quality Inspection Team is all over the place. Yup, that's my other cat, enjoying a new toy. Well, at least they get the box afterwards as they love to play and sleep in them :)

The box contained all the parts neatly packed and properly shielded with lots of bubble wrap. I pulled all the essential small parts out front to take this picture. In here you'll see the V-bottom of the cabinet, the gloves, the supplied blasting gun and four nozzles, the lamp and a power source for it, instructions manual and a bag full of nuts & bolts. Notice the grey foam around the V-bottom, this was preinstalled but I was not thrilled of it and the next pictures shows why.

Here I'm applying very liberal amounts of butyl sealant with a caulking gun. The sealant was a 300 ml tube from Biltema for 3.99 EUR and the gun also from Biltema for 2.99 EUR. The butyl sealant is good as it remains elastic and kind of rubbery when it hardens fully (around 1-3 weeks). Downside is the enourmous force needed to squeeze it out of the tube, as it is very thick.

The sealent begans to surfaceharden after about 20 minutes so there is plenty of time to install the parts and screw everything down. In the picture I'm just installing one of the sides to the V-bottom after applying the sealant. You can notice that I removed the original foam seal from the V-bottom. The reason is that I didn't like it and I had a tube full of this butyl sealant that I could install instead. I wanted a blasting cabinet that would not blow the blasting media all over my room from the small holes that would have been left in the corners and joints where the bolts are. Applying this sealant to all mating surfaces provides me an "airtight" blasting cabinet and helps to keep noise level and cleaning down.

The only difficulty I found installing all the parts was with the gloves. I couldn't keep them in place with only one hand while trying to fit the compression ring around them with the other. Finally I figured out that I could put the ring ready on the glove, fold the gloves edge around the ring and then install it in the cabinet. Worked well and got everything assembled. In the picture you see the original gun and its nozzles and the small 12 V transformer for the interior light. This is a nice safety feature as there isn't 230 VAC inside the cabinet. On the right hand side in the upper back corner there is a small yellow air filter that lets out the air but keeps the blasting media inside and also drops down the noise somewhat.

Although the cabinet has its own feet, I'm not putting it on a table but will make feet for it instead and write about them and one other mod I have in my mind.