Mäkelä Alu’s GSB-certified powder-coating lines can also handle small batches
19/09/2022
Mäkelä Alu offers a comprehensive service where all the customer’s further processing needs can be handled quickly, efficiently, and cost-effectively under one roof. Powder coating is a central part of our AluCoating® service concept, and its popularity has grown significantly over the years. Mäkelä Alu has four powder-coating lines in total, all of which are GSB certified to guarantee high quality. In addition to Mäkelä Alu, the GSB certificate can only be found at two other paint shops in Finland.
At Mäkelä Alu, we have developed our surface treatment services in such a way that even small batches and individual pieces can be coated cost-effectively.
“As many as 34 percent of the orders received at the powder-coating paint shop are single-piece orders. This staggering figure shows that we are able to meet all customer needs: even a single piece can be painted in any colour,” says production manager Vesa Saarenlaita.
We have already used more than 850 paint colours this year
Powder coating is an ideal aluminium surface treatment solution that is based on the use of electrical charges and heat. The powder paint adheres to the aluminium surface through electrostatic attraction, after which it is melted into a smooth and durable coating in a furnace. This gives the product an extremely hard surface that protects it against UV radiation, corrosion, abrasion, and impact.
“The colour options are endless, as there are thousands of shades available. This year alone, we have coated aluminium profiles in more than 850 different colours. The most popular colours are white, and various shades of grey and black. After these, the spread is rather large. In our powder-coating paint shop, you can find all the colours of the colour palette and see how boldly designers use colours today,” says Saarenlaita.
The paints are mainly supplied by Teknos, Axalta, and AkzoNobel. We also use three smaller suppliers according to the needs and wishes of the customers. This way, we can ensure that the customer gets exactly the right colour, as different manufacturers may sometimes have slight differences in shades.
Daily quality control
We have maintained the GSB certificate for 20 years. It sets strict requirements for the paints and pretreatment methods we use. They are the key to ensuring that the coating of the aluminium profiles can withstand demanding conditions – from strong sunlight to heavy rain.
In addition to regular external audits, quality tests are carried out daily at the powder-coating paint shop: coated test pieces are boiled in boiling water and subjected to raster tests, bending tests, deep drawing tests, drop-weight impact tests, and gloss measurement tests. The test pieces are stored for five years for possible later inspections.
Quality control also includes monitoring the thickness of the coating. The right thickness ensures a good surface quality for the profiles. Taking coating thickness measurements also helps us minimise our powder consumption.
Vertical powder-coating lines are perfectly suited for coating small batches
Investing in the efficient coating of small batches is a conscious and unusual choice.
“Our vertical powder-coating lines enable the effective coating of small batches. Our powder-coating paint shop in Voikkaa has been specially developed for handling small batches. At the paint shop, individual pieces can be guided along a separate line to another paint booth while the other paint booth is painting another colour. In this way, colour changes are possible without any loss in line capacity. Our vertical powder-coating line in Alajärvi also has two powder booths, so the colour change can already be started while the other powder booth is still painting the previous colour,” says Saarenlaita.
Currently, new coating lines are being planned for the Alajärvi horizontal powder-coating paint shop, which will take into account the need for quick colour changes.
Batching production by colour brings cost-savings
In order to make the coating process as cost-effective as possible, we aim to process profiles ordered in the same colour on the same day, because colour changes always generate some paint waste.
Last year, more than 40,000 colour changes were made in our powder-coating paint shops, which means an average of more than 3,300 colour changes per month.
“Reducing colour changes is important in terms of costs, especially since the rise in the price of materials is also reflected in paints and pretreatment materials. From this point of view, it would be beneficial if the customer could sequence their orders by colour. This would bring some cost savings,” says Saarenlaita.
FIGURES
- This year, the average batch size in our powder-coating paint shops has been 13 pcs and 53 kg: 7 pcs and 34 kg in Voikkaa, and 18 pcs and 69 kg in Luoma-aho.
- Out of all the different colours, our three most popular colours cover 24 percent of all painted profiles.
- This year, we have coated profiles in 853 different colours.
- On average, 5 kg of waste paint is generated per colour change.
In addition to powder-coating, our AluCoating® surface treatment services include anodizing, which is used, for example, in the furniture industry. It gives the product an attractive appearance and protects it against corrosion. Our anodizing line produces natural-coloured aluminium profiles. With the help of our partners, we can also provide coloured profiles. You can also finish your profiles with our decorative Decoral coating.
