| Author | Message |
|---|---|
 Chip_Bruh |
Date sent: 2017/05/24 16:51:48
So today i started my Lathe exam for Manufacturing Engineering, it took like 3 -4 hours to get the operation sheets and paperwork complete but today i finally started the practical :Di wanted to take a picture of what i was making but my tutor only allowed me to take a picture of where the Lathe's speeds / feeds / DRO is at so that when i go back to it tomorrow i can check that nothing has moved. He said i couldn't take a picture of the Drawing we have because i could technically revise it at home which is against exam conditions. http://imgur.com/a/RuxrA Anyways i'll describe the parts from memory, for all you lot that understand, such as Reki. i dunno who else is an engineer xP I drew my own sketches from memory to give you an idea of what i'm talking about. Basic info: Material: Medium Carbon Steel General Tolerance: +-0.2 There are two parts to the exam, a male and female which will mate. Task A (male part): DWG: http://imgur.com/a/a2KGy Explanation: - 100mm long x 22mm (at its widest point) bar, 1mmx45 chamfers either end. - There is a 32mm deep 7mm drilled hole from the right-hand side. - 39mm from the right hand chamfer, the dia. of the bar is 15mm. There's a specified tolerance for that, [+0.0mm -0.1mm]. - After the 39mmx15mm bar, there is a 3mm wide undercut, the depth for that is nominal. - the Dia. then extends to 22mm for 10mm long but there is a 2.5mmx45 chamfer on the left hand side of it. - After the 2.5mmx45 chamfer the bar is a 51mmx15mm, also as mentioned before there is a 1mmx45 chamfer on the end. Task B (female part): DWG: http://imgur.com/a/oxFU8 Explanation: - 33.5mmx50mm bar. - at the beginning on the right-hand side there is 12mm length. - After this gap there is an 8° taper. - On the inside of the piece, there is a reemed 15mm hole all the way through. - 7.5mm from the end of the far side of the taper there is a bore of 22mm dia. |
 Asriel🍆 |
Date sent: 2017/05/24 18:09:09
*is totally interested**sprays anti-sarcasm spray on self* lolnah fam |
Chip_Bruh |
Date sent: 2017/05/24 18:45:35
you cant be nice can you :/if you don't care, don't comment please. this post was intended for people who are interested, like Reki. He's been asking me a lot of questions lately about Engineering so i thought it'd be a decent read for him. i actually put a lot of effort into this post. |
 Aouldrain |
Date sent: 2017/05/24 19:36:22
This is pretty interesting actually.Cool chip! |
 NicNac |
Date sent: 2017/05/24 19:40:51
So are you like building parts to build machines? This looks pretty cool but I'm not sure what's going on. |
Chip_Bruh |
Date sent: 2017/05/24 19:56:53
xD to be honset i cannot remember the name of what we're machining, it is a real thing that is manufactured in the real world.i do however remember the concept... Basically, you see that male part? well that left hand part of it is supposed to be clamped into the chuck of a Lathe, the other end of the part which has that specific 'tolerance', is highly machined for the female part to slide onto. then, the person operating the lathe will clamp their work onto the female part somehow and machine their work that way, instead of clamping it in the lathe chuck itself. There is a feature to the two pieces which is two holes that perfectly align together; a highly machined pin goes through them and this pin holds them together and doesn't allow them to move. i'm not doing this feature on my work because it requires a technique that i have not been taught yet. it isn't as simple as drilling a hole, that'd be awfully inaccurate. |
Chip_Bruh |
Date sent: 2017/05/24 20:16:24
I drew up a cross section of the concept. the blue drawing represents the chuck of a lathe, the black represents Task A (male part), and the red represents Task B (female part).you can ignore the lines across the female part, they are just to represent that it is what you'd see if you cut it in half  |
 Matodir |
Date sent: 2017/05/24 21:14:29
I'm no engineer, however I found this very interesting ;o. |
 Michael9999995 |
Date sent: 2017/05/24 21:40:04
cool :D |
 Yoshkiksar |
Date sent: 2017/05/25 02:01:55
Is this only conventional turning or is there programming involved, the narrow angle on the female part would require a weird set up in order to get the angle correct. The male part looks simple enough, though i'm not too sure on how to do chamfers with conventional other than using a neutral tool. But honest to god idk how they're going to check the tolernace on the female's angle other than a little trig |
Yoshkiksar |
Date sent: 2017/05/25 02:02:35
Best of luck to you btw, I'll post more later since I'm not able to atm. |
Chip_Bruh |
Date sent: 2017/05/25 06:10:21
Conventional turning, there's no CAE (computer aided engineering) involved. All you have to do for the shallow setup is use an engineers pretractor to set the compound slide to 8°. Using trigonometry from maths, we can figure out the diameter of the end of the taper. All you do is cut using the compound slide until your taper goes down to the correct dia. Which of course you can calculate using the DRO.They measure the tolerance by Making sure that end distance is 12mm, and the dia at the end of the taper is correct. If the whole piece is the correct length then that angle MUST be 8° |
Chip_Bruh |
Date sent: 2017/05/25 06:12:13
Also thanks for the luck! :3 |
Chip_Bruh |
Date sent: 2017/05/25 14:46:08
Task A is complete :Dhttp://imgur.com/a/oa2Wt |
 Pixelpeeps13 |
Date sent: 2017/05/25 18:20:22
Good luck on part B! |
 Shindori |
Date sent: 2017/05/25 19:36:01
Oh good luck man, this is pretty interesting!You're studying manufacturing engineering if I read it correctly right? I will be studying electrical engineering at university next year ;P |
Yoshkiksar |
Date sent: 2017/05/25 21:18:27
Dat finish tho |
Chip_Bruh |
Date sent: 2017/05/25 21:49:37
Nice shin! my step dad was an Electrical Engineer!Also reki i couldn't help that, literally the best that we can manage due to the material not being particularly amazing, the machines aren't fixed to the ground and have a lot of vibration, also our lathes are very minimalist in the way of spindle speeds... :/ Automatic feed, 0.011 on the feed and 550 spindle speed. it looks terrible but if you run your nail across it you can't feel a thing. That finish is about as good as anyone can get ;-; |
