Author Topic: DIY Short block  (Read 13682 times)

AdeV

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Re: DIY Short block
« Reply #30 on: January 09, 2020, 08:07:04 AM »
Right - let's try to keep this polite shall we? It's entirely possible to get your opinion across without effing and jeffing or calling people liars/bullshitters/etc.
Cheers!
Ade.
--------------
1x Lister CS Start-o-Matic (complete, runs)
0x Lister JP4 :( - Sold to go in a canal boat.

dkmc

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Re: DIY Short block
« Reply #31 on: January 09, 2020, 08:28:05 AM »
I for one, am welcoming ANY traffic on this forum. Hasn't been much really in recent years. Welcome the debate, discourse, and doubters. Really hoping for a come back to the off-gridders, the modders, and the out-of-the-box free thinkers. Maybe here comes a turn around? Back to where we never was?
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sirpedrosa

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Re: DIY Short block
« Reply #32 on: January 09, 2020, 01:08:56 PM »
Hi AdeV

It was a matter of time... here we go again!

Now, for all members, I ask you kindly if anyone has a internal shematics of a bosh dynastarter 0 010 350 00.

Cheers
VP
By order of firing up:
Bernard 18A - 1968 (mama's water pump - year of my birth)
Petter PAZ1 - Jun 1967, 3HP, sn 416xxxx
Petter PAZ1 - Nov 1979, 3HP, sn 425xxxx
Lister 12/2 - 12651227, the pearl!
Deutz MAH 914, 1952 - Zündfix in chamber and go (7Mai2023).

guest25219

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Re: DIY Short block
« Reply #33 on: January 09, 2020, 03:39:19 PM »
Maybe this will be inspiring. Spent 15 or so minutes and modeled up an engine block just going off of photos (so things aren't to scale). I tried to model it in a way that someone with minimal shop access could do it. I'll also explain how i would go about trying to machine this. I should mention, IN THIS WRITE UP, I AM GLOSSING OVER A TON OF HOMEWORK YOU NEED TO DO REGARDING DIMENSIONS!!! Each plate is half inch thick steel. All welds are 3/8" fillet welds. Laser/plas/waterjet (whichever poison you prefer) your 6 plates. This is your chance to cut out the major geometry, don't worry about any threaded holes yet.

(Beer break)

Take your plates and weld them together. Now don't just go blasting welds at it. Now take your time with this. This isn't a race, go slow, take frequent beer breaks, weld short bead lengths, working around the block at different times to keep your heat even.

(Beer break)

(optional but recommended step)-Find a shop with a heat treat oven and have the weldment stress relieved. Or find an appliance store with an old stove. And convert it into your stress relieving oven. To do that just watch/copy this guy

(Beer break)

(Disclaimer...I'M NOT A MACHINIST!)
Next set your big steel block (this weldment will weigh around 100lbs) onto your knee mill with one of the sides (sides=plates with two big round holes) facing up. I would set this beast on some 123 blocks. I would indicate across the top and and shim it until its as close to zero runout as possible. Clamp er down...

(Beer break)

Take a shell mill, fly cutter, small file wielding army of ants, etc. and mill the area around the crankshaft/camshaft holes flat. Then punch your threaded holes for everything.

(Beer break/spray for ants)

Flip the thing over and set the milled surface on the 123 blocks and repeat everything on this side.

(Beer break, and did i mention I'M NOT A MACHINIST!!!)

Set the block upright square everything up by indicating off one of the sides you just milled. Mill the top flat. and then punch your threaded holes.

(bonus round)

Flip the block so its upside down with the milled top facing down on some 123 blocks. Now mill the bottom down until you are taking material off evenly all around it.

After all this go online, and do a long write up about what you did so everyone can tell you how you did it wrong and how you're the worst machnist in the world  ;D





Hopefully this helps with this discussion.  :D

mikenash

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Re: DIY Short block
« Reply #34 on: January 09, 2020, 05:15:35 PM »
Primo!

FWIW I would suggest some reinforcement at the big top threads.  Simply on the basis that for longevity a thread should be, minimum, the depth of its diameter plus a turn or two

Cheers

guest25219

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Re: DIY Short block
« Reply #35 on: January 09, 2020, 05:30:29 PM »
FWIW I would suggest some reinforcement at the big top threads.  Simply on the basis that for longevity a thread should be, minimum, the depth of its diameter plus a turn or two

You're absolutely correct! Thanks for pointing that out!

Willw

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Re: DIY Short block
« Reply #36 on: January 09, 2020, 06:42:01 PM »
Very interesting discussion, I say if you have the will, the means and can afford it ,why not give one or two a try?

The way I see it, and I'm speaking about prototype stage here, you might fail but so what? Analyze what went wrong and try again.
Another possibility, you end up with a working only-one-in-the-world Darth Vader type engine. What a conversation piece and advertisement for your fabrication shop!
Third possibility, you figure it all out and are successful. Cool.

Have a read of this similar discussion from back in the day https://listerengine.com/smf/index.php?topic=1844.0
Daily driver '97 GMC W4 tipper on WVO/Kerosene mix.
6/1 clone standby generator.
Too many projects.

dkmc

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Re: DIY Short block
« Reply #37 on: January 09, 2020, 09:52:47 PM »

Very nice effort Sirloin! A horizontal mill would come in handy, but I get that many don't have them. I suppose nuts could be installed on the cylinder studs inside the case for added strength. If there's room? This doesn't seem so difficult of a project, but then again they never do until you're into it. I build some things using the 'engineering on the fly' approach, and usually don't get bit to bad most times. Going slow, and planning each next move helps. This seems like a fun project, it would be a unique conversation piece for sure. 
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George A

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Re: DIY Short block
« Reply #38 on: January 22, 2020, 02:43:12 AM »
The idea of a welded assembly is always tempting, but you run into many of the problems already mentioned. Without a water jet and accurate, controlled cutting/welding the quality might be spotty at best.

Has anyone given any thought to just casting raw blocks? There are foundries operating in the Amish areas of this country that turn out excellent work for a decent price. All you'd need is an existing block so a pattern can be made, pour the castings and have machining done afterwards to accept the Indian parts.

There MIGHT be a problem if the EPA determines that you are a "manufacturer" and decides to clamp down, but if only a few are made at a time for "hobbyists" I really don't see a problem.

Okay...........that was my two bits worth.  ;)
I've joined "the dark side"....if it has a spark plug, it's obsolete technology.

guest25219

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Re: DIY Short block
« Reply #39 on: January 22, 2020, 11:28:10 AM »
There are foundries operating in the Amish areas of this country that turn out excellent work for a decent price. All you'd need is an existing block so a pattern can be made, pour the castings and have machining done afterwards to accept the Indian parts.

All the Amish in my area are either in the carpentry trade, or working in welding shops/trailer factories. Kinda wish we had a foundry nearby that was ok with the little onsy twosy stuff. Smallest foundry near me still prefers quantities in the 100's.

dkmc

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Re: DIY Short block
« Reply #40 on: January 22, 2020, 03:55:00 PM »


Cat Tail Foundry
Address: 167 W Cattail Rd, Gordonville, PA 17529
Phone: (717) 768-7323

If you google them you can read about many happy customers stories.
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George A

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Re: DIY Short block
« Reply #41 on: January 23, 2020, 09:47:54 PM »
That's the one. It sure couldn't hurt to submit either a scaled drawing or......better yet.......a complete block for an estimate. They'd have to make a wooden pattern and pour a casting, so the cost would be in that pattern and the amount of iron required.

Then there's the machining time on top of that, BUT you would have a genuine "made in USA" product. Enough calls for such a piece would bring the cost down.
I've joined "the dark side"....if it has a spark plug, it's obsolete technology.

dkmc

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Re: DIY Short block
« Reply #42 on: January 23, 2020, 10:11:25 PM »
It would be interesting to see a price quote from Cat Tail. In reality, I don't think there's much demand or interest as far as sales goes. Probably have a hard time selling 5 of the blocks in 5 years. I mean, who needs one? If someone has a block, they likely have a complete engine. Other than it's the major missing piece in the pile of most other easily obtainable and low cost parts. The one other piece I don't see readily listed on the spare parts web pages is Crank Shafts. Very few folks using these engines on a daily basis for 'work' I'd speculate.
« Last Edit: January 23, 2020, 10:16:41 PM by dkmc »
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snowman18

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Re: DIY Short block
« Reply #43 on: January 24, 2020, 12:50:50 AM »
If I were going to have an engine block cast at a foundry would make the rounds to the shops that work on highway rigs and farm equipment shops.

Collect enough scrap cylinder liners to cast an engine block.

I'm running two garden sized tractors made in the mid 1970's both have Onan engines that have never been opened up, a third engine that was seized from neglect not so much as a ridge on either cylinder bore.

The cast iron used was superior, and you paid a premium for an Onan.

Below is reference to diesel engine cylinder liners.

The liner can be manufactured using a superior material to the cylinder block. While the cylinder block is made from a grey cast iron, the liner is manufactured from a cast iron alloyed with chromium, vanadium and molybdenum.
« Last Edit: January 24, 2020, 12:56:51 AM by snowman18 »

snowman18

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Re: DIY Short block
« Reply #44 on: January 24, 2020, 03:13:41 AM »
Guys,

I have been thinking about building my own block from metal plate.  After a few rebuilds of my listeroid I have enough spare parts lying around to build another one

You can easily buy all the parts minus the block for cheap.  The blocks are next to impossible to find / source for a reasonable price.  Importing new engines is getting harder and harder

I have access to a machine shop with CNC waterjet, plasma and CNC machine

I'm thinking of machining up a simple block which would consist of metal plates around 1/4" or so welded together.  It would be more square / rectangular than the original but all the holes, etc would line up and everything would just bolt on.

What do you guys think?  has anyone done this before?  Am I crazy?  Should I start selling it as a DIY weldable kit?  lol
If the Indians can do it - why cant we?

It would certainly get more guys into the hobby..  What about flywheels?

John

You'll never convince me, for the following reasons.

Castings vs. Weldments/Fabrications

    One common method is to convert a welding (fabrication) into a sand casting.  The major consideration in cost saving is labor time.  The amount of time that can be saved by converting to a casting varies on: the alloy being converted, amount of welding spots, assembly time, and the total amount of pieces to be combined.  Other than total labor time saved; a major factor is the mechanical properties that a casting provides.

    A common problem in weldments is durability due to strength concerns where the pieces are welded together.  To combat such problems, engineers turn to castings to increase strength (among several other mechanical properties) due to the uniformity of pouring a casting.  It is important to note that the quantities have to justify the conversion and may not be right for each situation.  To the right is a picture of a casting that converted from a fabrication.

Benefits of Converting a Weldment to a Casting

    Overall Less Labor Time
    Time Until Part is Ready
    Better Mechanical Properties
    Better Appearance


http://info.cpm-industries.com/blog/bid/178199/Reducing-Costs-Converting-Weldments-into-Castings
« Last Edit: January 24, 2020, 03:17:20 AM by snowman18 »