Author Topic: Nemett 15cc 4 stroke engine  (Read 40968 times)

Offline HS93

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Re: Nemett 15cc 4 stroke engine
« Reply #25 on: August 07, 2011, 09:02:50 AM »
OK been and collected two boxes of books, there were four boxes but two are still hiding so not sure what is in those as they were never undone.
 
So at the moment I have 5 books and 6 sets of plans all brand new except that one book has all the material sizes highlighted in highlighter pen.
 
One thing that puzzles me is all the drawings are clearly marked Nemett 15S - 15cc SOHC Four Stroke Engine, sheets 1 to 15.
 
However the book clearly states "Constructing the Lynx"
"Note: This is designed to accompany the full A3 engine drawings. It does not contain any drawings. "
 
So is the Lynx and the Nemett the same engine ? Looks to me as it is because I can't see any differences but it would be nice to know.

John S.


Let me know what you want for a set

thanks Peter
I am usless at metalwork, Oh and cannot spell either . failure

Offline madjackghengis

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Re: Nemett 15cc 4 stroke engine
« Reply #26 on: August 09, 2011, 12:15:37 PM »
Hi Wheeltapper, that is a great looking engine to build, and while I have often shared your lament of shortage of tooling, remember, someone was making engines when he had to build a lathe first.  There is a way around every possible stumbling block, and while rotary tables are nice they are luxuries, not necessities.  I have used a level on my three jaw chuck to use my lathe as a shaper to cut splines for a PTO clutch in my tractor, many people have shown the use of "dropping verticals" off a line drawn at an angle to a line representing the circumference of something, and divided it very accurately that way.  Many rotary tables have been made using only common taps and constructed jigs.  When you make tooling for one project, you will find it is used long after that project is finished, typically.   :beer:  Cheers, mad jack

Offline wheeltapper

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Re: Nemett 15cc 4 stroke engine
« Reply #27 on: August 09, 2011, 01:56:36 PM »
Hi Jack
thanks for the kind words.
I'm the first to subscribe to the "making tools to make tools" way, but sometimes don't you just want to build the damn engine. :lol: :lol:

I should get the material for the cylinder liner and crankcase tomorrow so there should soon be some more pics.




Note the words' should' and 'soon' in the above . :doh:

Roy
I used to be confused, now I just don't know.

Offline wheeltapper

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Re: Nemett 15cc 4 stroke engine
« Reply #28 on: August 16, 2011, 11:42:03 AM »
Hi
back again.

A few more progress pics.

cylinder liner


part finished crankcase


and  an overview of what's been done.


thanks for looking.
Roy
I used to be confused, now I just don't know.

Offline DaveH

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Re: Nemett 15cc 4 stroke engine
« Reply #29 on: August 16, 2011, 12:37:53 PM »
Roy,

Well it is coming along very nicely, some very nice machining there as well. :thumbup: :clap:

Looking good, Roy :thumbup: :thumbup: :thumbup:
 :beer:
DaveH
(Ex Leicester, Thurmaston, Ashby De La Zouch.)

Offline wheeltapper

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Re: Nemett 15cc 4 stroke engine
« Reply #30 on: August 20, 2011, 12:54:40 PM »
Hi
I dont usually embarrass myself in public but I had to take a pic of this.
poor mans DRO.
can I nominate it for bodge of the year? :lol:

I had to move the mill table an exact amount for the hole centres of the con rod for this engine.
steel bar clamped to the lathe tray, square clamped to that, digital caliper clamped to the mill vise and the other bit of the caliper clamped to the square.

piece of wood to take out the spring. :bugeye:




am I mad or what?

Roy
I used to be confused, now I just don't know.

Offline NickG

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Re: Nemett 15cc 4 stroke engine
« Reply #31 on: August 20, 2011, 01:38:01 PM »
could have just used the dials!  :lol:
Location: County Durham (North East England)

Offline wheeltapper

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Re: Nemett 15cc 4 stroke engine
« Reply #32 on: August 20, 2011, 01:47:30 PM »
On this mill I wouldn't trust them as far as I could throw them.

Roy
I used to be confused, now I just don't know.

Offline Stilldrillin

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Re: Nemett 15cc 4 stroke engine
« Reply #33 on: August 20, 2011, 05:43:27 PM »
Nicely bodged Roy!  :clap: :clap:

I really like that........ :thumbup:

David D
David.

Still drilling holes... Sometimes, in the right place!

Still modifying bits of metal... Occasionally, making an improvement!

Offline doubleboost

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Re: Nemett 15cc 4 stroke engine
« Reply #34 on: August 20, 2011, 05:51:53 PM »
As long as it works  :clap: :clap: :clap: :clap:
Coming on nicely  :thumbup: :thumbup:
John

Offline andyf

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Re: Nemett 15cc 4 stroke engine
« Reply #35 on: August 20, 2011, 08:32:16 PM »
can I nominate it for bodge of the year? :lol:

That's even worse than the rig-up I used on my milling machine yesterday to trim the angled top and bottoms of the splayed wooden legs of a table for my grinder and (now mounted on a base) portable bandsaw!


am I mad or what?

If you are, you'll be the last to know. Maybe we should have a poll  :lol:

Andy
Sale, Cheshire
I've cut the end off it twice, but it's still too short

Offline Brass_Machine

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Re: Nemett 15cc 4 stroke engine
« Reply #36 on: August 20, 2011, 09:06:48 PM »
Mad skills on the DRO  :headbang: :headbang: We do what needs to be done!

Build is coming along nicely.

Eric
Science is fun.

We're all mad here. I'm mad. You're mad.

Offline wheeltapper

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Re: Nemett 15cc 4 stroke engine
« Reply #37 on: August 21, 2011, 08:16:17 AM »
Hi all.
Just a couple of pics of the finished crankcase.

Or
how to turn an expensive lump of aluminium into a hole  :scratch:




cheers
Roy
I used to be confused, now I just don't know.

Offline NickG

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Re: Nemett 15cc 4 stroke engine
« Reply #38 on: August 22, 2011, 04:27:02 AM »
Roy,

said it slightly tongue in cheek - I wouldn't trust my chinese mill dials either, except for over short distances ... the further I go, the larger the error gets, must be thread pitch error or something?!

I haven't got around to installing a DRO either. I've always debated whether to spenda  few hundred quid doing that or putting that money towards a better machine! I think a better machine would cost an awful lot though, unless I went down the older but better quality route like I have with the lathe.

Anyway, looking very good so far!  :bow:
Location: County Durham (North East England)

Offline wheeltapper

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Re: Nemett 15cc 4 stroke engine
« Reply #39 on: August 22, 2011, 07:50:39 AM »
Thanks Nick.
the trouble with my mill is for a start its an imperial one, they didn't have a metric version in stock.

the dials go from zero to 6o thou then a 2.5 thou gap back to zero. so you go from 0 to 60, turn the dial to 0, go to 60, turn to 0, and on and on and......................... :doh:

the measurement you want is in mm so convert to thou, divide by 60 for number of turns plus remainder.

by the time I've done that for a distance ( and lost count ) I may as well measure the space with a wooden rule and a piece of chalk. :bang: :bang:

silly bl##dy thing.

Roy
who will struggle on regardless :D
I used to be confused, now I just don't know.

Offline NickG

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Re: Nemett 15cc 4 stroke engine
« Reply #40 on: August 22, 2011, 11:08:22 AM »
 :lol:

Mine are 0-60thou too in 2 thou intervals I think, but I haven't noticed a 2.5 thou gap? Maybe that's why mine are innaccurate!

Location: County Durham (North East England)

Offline wheeltapper

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Re: Nemett 15cc 4 stroke engine
« Reply #41 on: August 22, 2011, 12:19:49 PM »
Nick,
heres a pic of mine


1 thou divisions and a silly gap.

Roy
I used to be confused, now I just don't know.

Offline NickG

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Re: Nemett 15cc 4 stroke engine
« Reply #42 on: August 22, 2011, 01:41:00 PM »
Cheers for that Roy, no mine definitely doesn't have the gap just checked, it's just cr@p!

Strange, guess they decided to use a 16tpi thread before thinking of the consequences?!  :doh: What thread does that make mine though?!

I often think about putting the digivern type scales on too which would be far cheaper but obviously not as good, have heard all the stuff about swarf, coolant and batteries running out, as well as not being able to see the screens. I need to save up for a proper DRO, think it will transform the mill.

Anyway, sorry for straying a little OT, good work around  :thumbup:

Nick
Location: County Durham (North East England)

Offline Stilldrillin

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Re: Nemett 15cc 4 stroke engine
« Reply #43 on: August 22, 2011, 03:58:07 PM »
Nick, Roy.
My first mini mill was 1/16" per turn. Drove me mad, after a working lifetime of "thous per turn"......  :bang: :bang:

Given chance to replace a few months ago. I bought same, but metric version.... 1.5mm per turn. With 75 divisions!!  :bugeye:  :bang: :bang:

1 turn gives .059"..... I could cope, if X & Y had 0-60 dials, like the Z axis.....   :thumbup:

David D
David.

Still drilling holes... Sometimes, in the right place!

Still modifying bits of metal... Occasionally, making an improvement!

Offline wheeltapper

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Re: Nemett 15cc 4 stroke engine
« Reply #44 on: August 22, 2011, 05:15:55 PM »
Jeeze,  that sounds worse than mine.

I started another thread here about this.

http://madmodder.net/index.php?topic=5907.0

I thought it would save dragging this one too far off topic.

Roy
I used to be confused, now I just don't know.

Offline Stilldrillin

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Re: Nemett 15cc 4 stroke engine
« Reply #45 on: August 23, 2011, 02:13:21 AM »
 :offtopic:     :offtopic:     :offtopic:     :offtopic:

Well done Roy!  :clap:

Let's get back to creating intricate pieces of metal........   :thumbup:

David D
David.

Still drilling holes... Sometimes, in the right place!

Still modifying bits of metal... Occasionally, making an improvement!

Offline wheeltapper

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Re: Nemett 15cc 4 stroke engine
« Reply #46 on: August 25, 2011, 08:42:44 AM »
Hi
Talking of intricate pieces of metal;
we have a piston.


the next job is making the piston rings. cast iron, lovely and messy, yuck.

Ive also gone mad and ordered a rotary table. its a 4" vertex and I'm getting the dividing kit as well so I can tackle the cams and other things .

Cheers
A very hard up Roy.
I used to be confused, now I just don't know.

Offline Stilldrillin

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Re: Nemett 15cc 4 stroke engine
« Reply #47 on: August 25, 2011, 12:12:47 PM »
Hi
Talking of intricate pieces of metal;
we have a piston.

Cheers
A very hard up Roy.

And a very nice looking piston it is too Roy!  :clap: :clap: :thumbup:

But, sorry......... Not able to help you with the hard up problem.  ::)

David D
David.

Still drilling holes... Sometimes, in the right place!

Still modifying bits of metal... Occasionally, making an improvement!

Offline wheeltapper

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Re: Nemett 15cc 4 stroke engine
« Reply #48 on: August 30, 2011, 08:13:42 AM »
I,m here again  :D

more intricate bits of metal.

from these,


to this,





AA cell for sizing.

cheers
Roy
I used to be confused, now I just don't know.

Offline saw

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Re: Nemett 15cc 4 stroke engine
« Reply #49 on: August 30, 2011, 09:36:00 AM »
Very nice work
 :mmr:
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