Lectii video de prelucrari mecanice

[Vizitator]

Pentru cine se descurca cu engleza un seminar video de tehnici de prelucrari mecanice pentru realizarea de prototipuri. Filmarile sunt din atelierul de prelucrari mecanice pentru robotica de la universitatea MIT. Seminarul este tinut de Erik Vaaler.

 

Machine Shop 1

Machining Skills for Prototype Development

http://techtv.mit.edu/genres/24-how-to/ ... ine-shop-1

Duration 40:32

1) Basic

2) Layout Techniques

3) Basic Tools: Drill Press, Band Saw, Belt Sander & Grinder

4) Locating and Drilling Holes

5) Tapping Holes

 

 

Machine Shop 2

Machining Skills for Prototype Development

http://techtv.mit.edu/genres/24-how-to/ ... ine-shop-2

Duration 57:33

1) Basic 2

2) Drilling Holes

3) Special Drills for Plastics and Hard or Abrasive Materials

4) Drill Press Limitations

5) Bandsaw

6) Suitable Speeds, Feeds and Materials

7) Bandsaw Setup

8) Using the Drill Press Vise

 

 

Machine Shop 3

Machining Skills for Prototype Development

http://techtv.mit.edu/genres/24-how-to/ ... ine-shop-3

Duration 30:02

1) Basic 3

2) Good Practice - Clean Up

3) Small Belt Sander Configurations

4) Grinder Operations and Materials

5) Deburring and Buffing

6) Finishing Techniques

 

 

Machine Shop 4

Milling Machine 1

http://techtv.mit.edu/genres/24-how-to/ ... ine-shop-4

Duration 50:33

1 Milling Machine 1 Layout & Use; what the different parts do

2 Quill Feed Allows you to move tool up and down

3 Axis Handfeed Feed/Crank on Axis with Dials to adjust the Bed

4 Gibb Locks Holds/Locks Bed to Saddle & Saddle to Knee and Knee to Body of Machine Locking Ring Adjustments

5 Power Feed Attached to one or more of the Axes Forward/Reverse Knob and Variable Speeed Control

6 Digital Readouts Measure position of Axes to 0.001" or in mm

7 Milling Machine Set-Up Squaring the Head Square=Z-zxis of head [Quill] is perpendicular to axis of Bed

8 Squaring the Vise Adjusting the vice so back [stationary] jaw of vice is parallel to bed Machine Safety, Protocol, & Shop Safety 9 Milling Machine Accessories & Workholding Techniques Milling Machine Tools Drill Chuck-drilling & reaming Boreing Head-more precise cutting to 0.0002" Fly Cutter-used to square up a part [4 teeth and 1 single tooth] End Mill-shank type milling cutter Collett Chucks-holds End Mills Saws-used to make deep narrow slots-installed on an arbor Reamers-used to smooth out inside of drilled holes Edge Finder & Center Finder-used to locate punches or holes on a milled part Boreing Tool-Used on a shank head to bore holes

 

 

Machine Shop 5

Milling Machine 2

http://techtv.mit.edu/genres/24-how-to/ ... ine-shop-5

Duration 1:03:33

1 Milling Machine

2 Square and Hex Collett Blocks-used to hold/clamp parts to machine features on 4 and 6 sides of a part, respectively 2 V Blocks Holding parts to machine features into parts and end of parts

3 Hold-down Clamps Used to hold large or irregularly shaped parts

4 Using Angle Blocks Used to hold materials to machine features not perpendicular on a part

5 Drill Press Vice Used to hold a part to machine a feature @ 45? angle and other positions/angles Also used with angle blocks to hold parts

6 Lathe Chuck With Vise Used to hold parts in the milling machine; not accurate method, but quick/convenient

7 Double Sided Tape Used to hold a part in a vice securely without distortion

8 Squaring High Aspect Ratio Parts Used to hold a part to be machined securely and squared

9 Right Angle Attachment A right angle gear box to mill features in an end of a larger/slender part that is clamped in the vice.

10 Slitting Saw A saw blade that is used to cut slots/slits/features in a part Can also be used with a right angle attachment

11 Rotary Table A bench/table attached to the bed of the machine used to machine circular parts, grooves, circles, segments Dial indicator and Co-Axe indicator uses to square/center the Table to the Y axes

12 5 C Collett Indexer Used to hold Colletts and position parts in up to 24 positions for various milling features

 

 

Machine Shop 6

Milling Machine 3

http://techtv.mit.edu/genres/24-how-to/ ... ine-shop-6

Duration 46:33

1 Milling Machine 3 Squaring a part, maching all surfaces so they are flat and perpendicular to one another and nominally to the part that will be milled; removing burrs

2 Squaring a Plate Squaring the sides of a part/plate to the dimensions of the finished milled part; remove burrs

3 Using the Edgefinder Used to locate the edge of a part relative to the spindle of the machine

4 Drilling Holes Drill press used to drill holes in parts; center drill milling and other drill bits; setting depth stop

 

 

Machine Shop 7

Milling Machine 4

http://techtv.mit.edu/genres/24-how-to/ ... ine-shop-7

Duration 45:33

1 Reaming Holes Reamer is used to make a drilled hole larger and smoother within 2/10000" of it's diameter

2 Boring Holes A Boring Head is used for making very accurate holes; also used on a quill producing more accurate holes

3 Milling a Slot End Mills used to mill slots in a piece

4 Milling a Shoulder Conventional & Climb Milling

A Shoulder or step milled into a piece Conventional Milling-part is fed against the motion of the tool; best for rough cuts Climb Milling-Part is being fed along with direction or rotation of the tool; better surface finish cuts

5 Cleaning the Machine

Very important in the use of milling machine; chips, dust, etc.. Needs to be cleaned Only a brush or vacuum should be used. Air should never be used; this risks blowing chips into machine and possibly damaging it Most accidents in a machine shop happen when bringing parts to a machine or when the machien is being cleaned

 

 

Machine Shop 8

Lathe 1

http://techtv.mit.edu/genres/24-how-to/ ... ine-shop-8

Duration 45:02

1 The Lathe Components @ Set-Up Axes and Feeds

2 Turning Tools

3 Turning and Facing

4 Cutting Off a Part

 

 

Machine Shop 9

Lathe 2

http://techtv.mit.edu/genres/24-how-to/ ... ine-shop-9

Duration 47:33

1 Tapping

2 Boring

3 Knurling

4 Cutting Tapers with the Compound

5 Turning Shafts Use of live center

6 Single Point Thread Turning

 

 

Machine Shop 10

Lathe 3

http://techtv.mit.edu/genres/24-how-to/ ... ne-shop-10

Duration 34:32

1 Lathe Chuck

2 Lathe Arbors

3 Turning Between Centers

4 Face Plate Irregular Shapes

5 Face Plate Thin Materials

[fenobarbital]

Vreau doar sa spun ca pe mine m-au ajutat foarte mult; poate sa se considere un "up" ca si la topicul de vinzari.

[en]

Cu adevarat, este foarte instructiv si utilajele sunt pe masura reputatiei MIT. Mai ales pentru cei a caror pasiune incepe sa faca primii pasi, este chiar deosebit acest serial.Pacat ca rezolutia este cam slaba. Voi aveti probleme cu rezolutia la vizionare?

[romioltean]

la fel se vede si la mine, se pare ca nu e o problema de la noi

[Vizitator]

De ce ar fi nevoie de o rezolutie mai mare? E ceva ce nu se înţelege din cauza asta?

[romioltean]

ne-am obisnuit cu filmul de rezolutie mare ,pe de alta parte informatia "face toti banii"

[en]

De ce ar fi nevoie de o rezolutie mai mare? E ceva ce nu se înţelege din cauza asta?

:bere: Ce zici tu acum, mi-aduce aminte de perioada cand in tara era la moda francofonia. Si cand se regulau strigau;"O la la,oui,oui!!"Acum suntem anglofoni si nu stiu cum se mai striga... Si ca sa nu fiu offtopic,rezolutia este necesara penrtu a putea surprinde alte detalii tehnice, pe care ai putea sa le adaptezi la momentul potrivit.Una peste alta,materialul prezentat, este de o excelenta calitate ca informatie in sine.

[Vizitator]

rasputin a descoperit pe YouTube un film foarte intersant pentru înţelegerea proceselor de prelucrare prin aşchiere.

Ceea ce veţi vedea este filmat sub microscop la Laboratoarele pentru Cercetarea Materialelor din Melbourne în colaborare cu Centrul Naţional de Tribologie din Risley, U.K.

http://www.youtube.com/watch?v=Asra3gnB9EQ

Mulţumiri pentru link rasputin.

[hene]

Concluzii pe marginea filmului (foarte interesant de altfel):-otelul se comporta "plastic" la strunjire, si se acumuleaza resturi pe cutit de otel rapid acestea ducand la o taiere neregulata si un aspect neuniform -daca scula are acoperire de nitrura de titan, aceasta actioneaza ca un antiaderent pentru span si dispar problemele sus-mentionate-dupa cum toti stim inoxul este dificil de prelucrat. Filmul arata clar si de ce: se comporta precum "plastilina" si se lipeste pe scula aschietoare.