Author Topic: TOTAL BRAIN FADE  (Read 694 times)

Offline Robert Hornby

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TOTAL BRAIN FADE
« on: July 17, 2020, 10:02:21 AM »
The Mill Engine build is progressing quite nicely up to today. I am unsure if it because I am getting old (77) or just stupid (or both) but I seem to be making silly mistakes recently and todayís one takes the cake.

I have arrived at the stage of making the eccentric for the valve drive. The design calls for a 6mm valve stroke and after milling out the ports and after measuring and calculating the exact stroke needed so as to have the valve aperture covering the inlet port and the port to the cylinder I worked out that the stroke required was 6.1mm  All OK I can make the eccentric to achieve this.

So at a stroke of 6.1mm the offset between the crank pin and main bearings will be 3.05mm. Straight forward math.

Now how to bore the eccentric hole? Put it in the drill/mill and drill and ream the 10mm hole required or boring it in the lathe in the 4 jaw chuck. I felt that I would have better control of alignment and size by using the lathe.

 So set it up in the 4 jaw and with the 3.05mm dimension in the forefront of my mind and taking extra care to get the offset exactly at 3.05mm with the dial gauge I pilot drilled the hole the bored it out to the required size of 10mm

Assembled the eccentric with the strap and rod to the valve gear then viewing the movement of the valve in the chest I was amazed/confused/surprised/disillusioned/disheartened to find the valved only moved half of what I expected and indeed required.  How could that be? I was so careful with the set up.

I downed tools, turned off the workshop lights and retired to the lounge with gin and tonic and wondering how I went so wrong. After a few G & Tíees the penny dropped. The 3.05mm offset is fine if doing the job on the mill and indexing over, but on the lathe I should have the offset at the full 6.1mm OBVIOUSLY.

IDIOT/NINCOMPOOT/DUNDERHEAD and lots more expletives.

So a lot of time wasted or can I put it down to learning (I suspect I am too old to learn anything new)
Age and treachery will always overcome youth and skill

Offline mikemill

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Re: TOTAL BRAIN FADE
« Reply #1 on: July 17, 2020, 11:20:21 AM »
Robert

Donít worry you are not the only one who is infected with daft actions, I spend hours making a part then put it on the bench go off and do something else then return to pick up the part but itís gone. Then spend what seems forever retracing my steps checking to see if I put it down somewhere else, now exasperated return to the bench to find the part hiding behind a tool, with no memory of putting it by the tool, all very frustrating just a function of age!!!
Keep up the good work your engine is looking excellent.

Mike

Offline steamer

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Re: TOTAL BRAIN FADE
« Reply #2 on: July 17, 2020, 02:43:26 PM »
+1.....

Been there ...done that....got the T shirt.....sometimes twice in a row!....

....there's always another piece of stock....

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline Tom1948

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Re: TOTAL BRAIN FADE
« Reply #3 on: July 18, 2020, 01:37:55 PM »
WOW, Can I relate to what mikemill said.

Offline mcostello

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Re: TOTAL BRAIN FADE
« Reply #4 on: July 18, 2020, 07:58:06 PM »
The worst one I ever did was, I was grinding a weld off of a piece of steel around 1" square and 3=4" long. The phone rang and I set it in the water pot to cool off. It was under water. Made another and it took about 2 weeks before I finally remembered what I was doing when it happened.
The other thing was I have a tool I made. It never leaves a 16'x20' room. I set it down and cannot find it. So I started checking all My drawers (tools that is.) I thought I would make a list to save duplicating the search pattern. Did not write down what I was looking for. Now I have a list that tells Me something is lost and I know where it is not. :Lol:

Offline steam guy willy

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Re: TOTAL BRAIN FADE
« Reply #5 on: July 19, 2020, 12:30:13 AM »
Hi, I have a propensity for loosing tools ..so much that one day I decided to observe my actions ,,,,,and sure enough when I had finished with a chisel ...I actually chucked it to one side of the bench about 3 feet away  !!! then picked up the next item... so now I look in the opposite direction to where I have picked up the new tool from  ? !!! also it is always in the last place you look so...look there first ?? :lolb:

willy

Offline Hugh Currin

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Re: TOTAL BRAIN FADE
« Reply #6 on: July 19, 2020, 02:48:30 AM »
I can certainly relate to that. The last time I... Wait, what was the question?

Stay well.
Hugh

Offline crueby

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Re: TOTAL BRAIN FADE
« Reply #7 on: July 19, 2020, 03:19:43 AM »
I can certainly relate to that. The last time I... Wait, what was the question?

Stay well.
What question?   :lolb:

You know its bad when you  are looking through things on the bench for a part, moving them with your right hand. Then, shift something from your left to right hands to look with that, then realize the thing you shifted WAS the part you were looking for....   :shrug:

Offline mikemill

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Re: TOTAL BRAIN FADE
« Reply #8 on: July 19, 2020, 11:06:00 AM »
Just to add to the mayhem, what about when that small part pings out of the vice or you drop it, then spent an eternity on you hands and knees looking for it and if itís round ends up six foot away from where you are looking!!!

The positive is when you find the part you dropped last year.

Still going crazy

Mike

Offline tghs

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Re: TOTAL BRAIN FADE
« Reply #9 on: July 19, 2020, 12:59:08 PM »
the third day with my new mill I spent 30 minutes of the hour of free time I had looking for the spindle lock tool.. later that day I decided that would never happen again,, the yellow had to do I didn't have any day-glo paint on hand..
what the @#&% over

Offline Admiral_dk

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Re: TOTAL BRAIN FADE
« Reply #10 on: July 19, 2020, 09:22:18 PM »
Careful Gentlemen or this might be the longest thread on the forum ever - or should I call it "the Neverending Story"  :old:

As bad memory has been a part of my life since my big accident April 1st.1994 - I'm sure I can relate, if I can remember enough to tell ....  :wallbang:

Offline steam guy willy

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Re: TOTAL BRAIN FADE
« Reply #11 on: July 20, 2020, 02:51:10 AM »
You will never lose the chuck key if you leave it on the chuck !!!

don't try this at home or in the WKSP !!!

willy