Any metal can be easily sandcarved and all metal etching with SR3000 produces a sharp quality result in a very short time frame. To sandcarve and paint fill a stainless steel plaque you need just 40 minutes to complete the job resulting in a high profit job if you charge the going rate for metal engraving.
Sandblasting becomes an easy solution for metal objects that are not flat. Rather than lengthy set up times in setting up jigs and machine prep you simply apply the SR3000 PhotoMask resist, tape up around the area and blast away. Quick and easy. Items such as Brass bells, tools machine parts that need labelling can be quickly permanently marked via sandblasting. Sandcarving often makes complex jobs quick, easy and profitable.
It is important to note that you don’t achieve depth into the metal surface (other than on pewter or zinc). Rather, you achieve a surface etching which is permanent and the abrasive surface is ideal for paint filling as it becomes a perfect keying surface for paint to stick to. As long as you use good quality paint you will create a plaque that looks great for many years.
Metal items can be etched and paint filled or left non-paint filled. Most items get paint filled but some label marking items just get etched leaving a tonal change from the original metal surface.
The metal etching technique is about the same as glass etching. It’s straight forward and just as easy. Let’s go through some tips and tricks for sandcarving metal.
Most metal gets paint filled and so it is best to use 5mil resist as it is thicker than the standard 3mil and peels off easily. 3mil gets a bit gooey after blasting and under paint whereas the slightly thicker 5mil stays rigid and peels off easily. Take a look at our training document on paint filling to hone your paint filling skills.
All metal surfaces should be wiped down with an alcohol cleaning fluid if it does not have a protective surface.
Stainless Steel with a number 4 brushed finish surface is tough and easy to handle and etch to etch. Mirror finished metals obviously need adequate protection.
Brass with a brushed finish is easy but all brass is prone to scratching so be careful working with it. Paint filling is easy but take extra care when peeling off the resist so as not to scratch the surface. Once the job is done you can apply a clear coat just like you normally would.
Some brass such as O’Brien Engineering Lacquered brass can be etched and paint filled leaving a fully protected surface. As the metal already has the lacquer you must adhere to special principals of etching lacquered surfaces as laid out in the Sandcarvers Training Manual.
There is a great Brass alternative which is brass coloured stainless steel (sometime referred to as titanium brass). This item does not tarnish like normal brass and is easy to handle in production.
Pewter Drinkware can be sandcarved and some depth can be achieved however check if the tankard has a lacquer coating (most do) as this needs to be handled carefully during the carving process. The heat from the blast reacts with the lacquer and can cause staining. So put a little extra distance between the nozzle and the item and don’t leave the resist on for too long. Detailed information can be found in the Sandcarvers Training Manual.
Aluminium is also simple to etch. Some aluminium surfaces have a waxy finish so wipe down well with a cleaning alcohol. Anodised aluminium and powder coated aluminium sandblast easily and if dealing with a coloured surface you get a good contrast.
Lacquered Surfaces can sometimes be a problem as the heat reaction to the photopolymer resist makes it stick tightly to the lacquered surface. The Training manual has extensive information on this. One thing that can be done is apply a very light barrier coat of RZ2 to the surface before etching. Here's a video on this.