Challenging parts for training

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Hey guys
Im about 6 months into a fitting and machining apprenticeship and to put it simply im not learning anything as far as the machining goes (im 19 btw).
The parts that we make are so basic im not sure id call it machining.
What scares me is that not long ago i made what i was told is the most complex part thats made in house, but really it was a walk in the park,ill post pics when i get the chance.
The problem i think is due to jumping so far ahead by myself that there just isnt anything at work that i find challenging.
I basically went into the job on my first day and started making parts with no training at all.
My supervisor is willing to try and help me out but isnt getting very far.

So what would be really helpful would be if you could post some pics of REALLY complex parts that were made on manual machines, be it for work or hobby. What would be even better is if you could post the plans too so i can have a go at making them and hopefully learn something.

Im hoping this will help by being able to go to my boss and say i need the skills to be able to machine this.....

Cheers, looking forward to hearing your comments
Jonathan
 
Hi Jonathan

If you want to see some REALLY challenging machining take a look at keith5700s post about his 1/4 scale V8 petrol engine it's mind boggling even the real experts here have dropped jaws about this one.

Regards Mark
 
I would love to make stuff of that complexity, i have the plans for steves v8 that i want to build but i dont think theyd let me do that at work :p
 
In my experience, manual machine parts are complex because they require imaginative fixturing. Once the stock is in place, the machining is "simple".

Take a look at George Britnell's radial engine project: http://www.homemodelenginemachinist.com/f31/5-cylinder-radial-winters-project-15122/

He has plans as well.

This is very true Jigs and fixtures can and often do, take more time and effort than the actual machining which is quite often a robot like handle turning exercise.

It is especially so due to the "one off" nature of much of the work we do. You still have to make that special mandrel, or clamp or whatever, even if you only use it once.

Regards Mark
 
Johnathan ;
I think part of the problem is what you are asing is a bit open ended.and the answer will be based on your personal perspectives and preferences. and we are not you. but not a problem.
there are a zillion projects out there to be machined.. More than most of us can do in a lifetime. this site may help http://www.projectsinmetal.com/
fill you tool box with tools you have made. in days of old before the cheap import stuff machinists made many of there own tools. machinist jacks. v blocks. 1-2-3 blocks , clamps vises, plumb bob. etc. .

there are many tools, accessories and upgrades to be made for the import mills and lathes if you have one of those. a scissor type knurling tools is a nice thing to have and do one better make it for a quick change. tool . carriage stops for the lathe.

Look around you there are many things that are machined pick something and copy it. come up with several options show them to your forman. people like having options and chooses. present one Idea and the answer is yes or no.

Tin
 
Your quite right Tin sorry about that. What i was trying to say is that it would be good to see some of the parts that people have come across at work that are particularly difficult. is that any clearer? i know its a bit of a stretch as most people wouldnt take pictures of that kind of thing.
Does anyone have any examples of step off contouring like what was shown in the 5 cylinder radial link a few posts back? that kind of thing would be very good to know how to do
 
Knowledge is cumulative. Start with simple stuff and work your way up. Build a Webster engine. Its a great stepping off point.
 
The only difficult part of machining is breaking complex shapes into simpler tasks, and doing it without messing up the previous work.
One of my first lathe projects when I got my south bend as a set of brass candle sticks for my wife. These were a rough castings and a drawing of what it was supposed to look like when finished. this was very much eyeball hand coordination seat of the pants art machining . nothing in the way of critical dimensions. The trick was to make the pair look like a pair not different items.
I then decided to make a doll house copy. so I drew out the design on a piece of tool steel and ground out the candlestick frofile . Again eyeball art. just a coulpe of dimesions to keep scale so it looked right. here is a pic of the little one.
thumb2_candlestick.JPG

so you want complicated contours make a pair of candlesticks.

One of the guys I know who is a pro machinist used to make router blank by doing eyeball eye hand coordinated pieces. this was the steel part the carbide was brazed to after the reliefs were milled out. Before the days of wide spread cnc die makers would machine cutting dies for the shoe factories on a Bridgeport again eye hand coordination following the layout lines. .
you want another challenge make an s spoke fly wheel . turn the blank lay out the pattern drill holes for the radiI and then mill out the "S" spokes without jigs or a rotary table. or use the pin and rotary table if you want. You could just make a pattern from plastic or wood.
Tin
 
I started off copying a "Steamco" oscillating engine and made a mess of it but persisted.Bought books written by Tubal Cain,titled Building Simple Model Steam engines,Book 1 & 2. Drilling the steam inlet/outlet ports accurately to good alignment was trying.Made about 6 such engines and from there went to build slide valve engines.Also made a mess of it.

Took eight years to gain sufficient experience/skill to build the My First Glow Plug Engine.I got smart I seek expert advice from the senior forum members.
Also bought plenty of reference books to brush up. My apprenticeship in general machineshop did help arming me with basic skills.

The forum is a very good venue to seek expert advice as most members are veteran machinist/
tool & die makers,welders,fitters,engineers,craftsmen.

The "American Pop Corn Steam Engine has many simple parts to machine and could be build
by an experienced beginner.Took four months to complete.The Sphereical Governor Weights were cut with help of DIY Rotary Table.The Spoked Flywheel idea came from some magazines. See foto.

IMG_0668.jpg
 
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