|Scraping of plane surfaces - Course: Technique for Manual Working of Materials. Methodical Guide for Instructors|
In order to guarantee a trouble-free development of the instructions, exercises and practical work it is necessary to prepare this training appropriately.
2.1. Preparations for instructions on labour safety
Prior to the exercise a brief instruction in the proper use of working tools has to be given. This comprises also hints for accident-free work. The main emphasis is to be laid on:
- Flawless scrapers must be used only
- The scraper handles roust not show any cracks
- Workpieces roust be clamped in such a way that they do not become distorted by the clamping forces
- Scraped surfaces must be protected from damage - they must be covered
- Surfaces of tools for checking against master plates must be protected from damage - to be oiled after use!
Familiarity with these hints has to be confirmed by the trainees signatures in a control book.
2.2. Provision of teaching aids
- For the purpose of demonstrations during the instructions a small surface plate has to be installed at a workbench, and a vice should also be at the site.
- The Trainees Handbook of Lessons - Scraping of Plane Surfaces is to be handed out to the trainees in sufficient numbers.
- When using the transparencies series of Scraping of Plane Surfaces, check whether they are complete (transparencies nos. 6.1. - 6.3.) and whether the overhead projector is functional. (Check the operation conditions at the place of work and make sure of the proper mains supply I)
- Surveys etc. which are to be written on the blackboard have to be completed prior to instruction.
- All the tools and accessories mentioned in section 3 should be kept ready for illustration purposes.
2.3. Provision of working tools and materials
- Sufficient copies of the Instruction Examples for Practical Vocational Training - Scraping of Plane Surfaces must be handed out to the trainees to provide them with the theoretical foundations of the exercises to be carried out.
- The initial materials necessary for the exercises have to be prepared and laid out in sufficient numbers according to the materials mentioned in the Instruction Examples....
- Each trainee is to be provided with a workbench at which the respective clamping devices and surface plates are firmly fixed and which is sufficiently lit.
- The trainees workbenches have to be fully equipped with tools and accessories according to the envisaged exercises.
Recommended basic equipment:
- steel rule, bevelled steel straight-edge, vernier caliper
- bastard and smooth files 200 - 300 mm (flat)
- hand hacksaw
- locksmiths hammer, aluminium hammer
- flat scraper, pull-type scraper
- checking ink, inking block, levelling straight-edges
- bench-type or column-type drilling machines with the appropriate clamping devices (machine vice, holding clamps, C clamps) for necessary preparations (drilling) in certain exercises.
- Before the exercises are carried out, the drilling machines compliance with the requirements of labour safety has to be checked.
2.4. Time schedule
Time planning is recommended for the following training stages:
- introduction to the working techniques in the form of instructions
- necessary demonstrations
- job-related instructions for preparing the exercises
- carrying-out the exercises
- recapitulations and tests.
The necessary time share depends on the respective training conditions. Most of the time is to be allocated to the exercises.