Some of the parts of the Wörner B13 were originally blackened. Rust have ruined most of those finishings. Thus I was faced to polish them to clear metal or try to recover original black coating. I found interesting to experiment with those cold blackening solutions and give them a try. What follows is the resulting experience.
The parts to be processed were:
- The screw plug of the quill retention.
- The handle and bearing support of the belt tensioning pinion.
- The thumb screw of the feed lever.
- The return spring cover.
The thumb screw was missing and a new one was made in the lathe some days before. Following, there is a picture of the cleaned spring cover. This is not the original spring cover but a replacement made after some previous reparation.
The cold blackening process I used was that sold by GIMA. I used the 100ml burnishing set which was largely enough. The parts were previously cleaned with a home degreaser. After that, the blackening process was exactly done as required in the product instructions. I used deionized cleaning water between each step.
The result was good enough. A nice black finish was formed and its resistance was better that I expected. I would say that depending on the steel characteristics things go better or worse. This is said clearly in the product datasheet. Overall, the results exceeded my previous expectatives.
These are some pictures of the parts after being blackened.
This is belt tensioning handle mounted on the drill head:
