Call Bosch's legacy parts department. Provide model number KL 1206 and serial number (if available). They may email you a PDF of the original operating instructions. This works better in Europe than in North America.
Warning: Avoid random PDF download sites that require you to install an "exe viewer." These are malware traps. The genuine Bosch KL 1206 user manual file size is between 2 MB and 8 MB.
Some users have uploaded the manual to Scribd. You can view it with a free trial, but ensure the document is complete (some uploads are missing pages 4-5, which contain the electrical schematic). bosch kl 1206 user manual
Used models often need brushes. The manual specifies:
You might think a heat gun is straightforward—point and blow hot air. But the KL 1206 has unique characteristics: Call Bosch's legacy parts department
Without the manual, you risk damaging the tool or voiding any remaining warranty (if you somehow have one from the 1980s).
Search for "Bosch KL 1206 original manual" on eBay. Prices range from $10 to $30. Vintage tool sellers sometimes include a photocopy when you buy a refurbished unit—ask them for a scan. Some users have uploaded the manual to Scribd
If your search for the Bosch KL 1206 user manual is completely unsuccessful, consider these options: