IDENTIFIKASI KESALAHAN ESENSIAL GAMBAR KERJA PRAKTIK PEMESINAN DI SMK MUHAMMADIYAH 1 BANTUL

Abstract

Penelitian deskriptif dengan menggunakan metode studi kasus ini bertujuan untuk mengidentifikasi kesalahan esensial gambar kerja praktik pemesinan kelas XI di SMK Muhammadiyah 1 Bantul. Subjek dari penelitian adalah gambar kerja praktik pemesinan kelas XI SMK Muhammadiyah 1 Bantul. Objek dari penelitian adalah kesalahan-kesalahan esensial gambar kerja praktik pemesinan. Data dikumpulkan menggunakan instrumen penilaian dan dianalisis dengan deskriptif kuantitatif. Hasil dari penelitian ini didapatkan jumlah kesalahan pada gambar kerja 1-8 terdapat total 183 kesalahan. Hasil penjabaran data penilaian menunjukan kesalahan pembuatan gambar pada etiket dari gambar 1-8 total persentase kesalahan adalah 20%, garis dan huruf 9%, penunjukan ukuran dan toleransi 66%, penyajian benda (proyeksi) tidak terdapat kesalahan, potongan (irisan) tidak terdapat kesalahan, kondisi permukaan 5%.  Total persentase kesalahan tiap gambar kerja: bubut 1 (4%), bubut 2 (7%), bubut 3 (8%), bubut 4 (12%), bubut 5 (28%), frais 1 (5%), frais 2 (6%), dan frais 3 (29%). Keseluruhan penilaian kesalahan setiap gambar kerja adalah dalam kategori baik.

The research is a descriptive research using case study methods. The purpose is to identify the essential errors in the engineering drawing of machining practices used in class XI of SMK Muhammadiyah 1 Bantul. The research subject is the engineering drawing of machining practices. The research object is the essential errors of the engineering drawings. Data were collected using the assessment instrument and were analyzed by quantitative descriptive. The results identify the amount of errors in the drawings 1-8, totalling in 183 errors. The elaboration of assessment data shows the errors in the drawings: 20% errors are in the title block, 9% errors are in the lines and letterings, 66%, in dimensioning and tolerancing, 0% in projection, 0% in section views, and 5% in surface roughness. Details of the errors for each drawing sets are as follows: turning 1 is 4%, turning 2 is 7%, turning 3 is 8%, turning 4 is 12%, turning 5 is 28%; milling 1 is 5%, milling 2 is 6%, and milling 3 is 29%. All of the assessment of errors in each engineering drawing are in the category of “good”.