Sandblasting is a great way for completely removing rust. However, in case of relatively thin sheet metal of vintage cars you need to be careful. The impact of the grit and deform the panels due to the heat that develops. After searching the web I learned about sodablasting and found Emo Stubbe of Soda Blasting Twente. Based on his experience he advised me to use olivine sand instead of soda.
Sandblasting using olivinesand
He uses the smallest possible grain and low pressure which guarantees that the sheet metal does not deform. To get familiar with the process and meet Emo, I had the suspension parts sandblasted.
The blast cabinet
It is very nice and clean! I would never have achieved this using a wire brush. Next step is to preserve it using RX5, replace the bushings, where needed repair screw-thread. Finally I will coat it using black RX10.
While further inspecting the parts I found out that the has some holes. This shows the importance or sandblasting. Only by using this approach you are sure that you end up with only solid steel. The left support arm has some weak aera’s around the silentbloc both on the sides and the upper arm itself.
I am going to look for a replacement. Welding suspension parts is not allowed for the MOT and also not preferable. The rear load will increase and must be 100% OK. Luckily the left rear trailing arm is abvailable new in case I cannot find a good used one.
Nevertheless did I treat all parts today using RX5 to prevent the blank metal from rusting.
I have removed the inner bushings and old rubbers from the lower support arms.
I leave the outer bushings in since I am going to upgrade to polyurethane (PU) of which two types are available:
- Control arm silentblock lower PU set without bushings
- Control arm silentblock lower PU kit (incl. outer bushings)
The first one is cheaper and can be used when the outer bushings are still OK. For my control arms this is the case. Even the rubbers itself were not too bad on the right hand side.
I have coated the control arms with RX10 mixed with some RX5 to make it flow more easily and add another anti-rust layer.
The last step is to coat it using undiluted RX10.