# 80cc DOHC V8



## pat1967 (Oct 31, 2010)

Hi Guys,

I received the material for the pistons the other day, so went about making up the piston blanks during a few hours I had to spare in garage. Firstly, as there were 8 pistons, I wanted to try and minimise doing multiple setups and measuring, and couldn't really justify making a jig. So I went with the approach of machining a stub, that I could pickup in the collet chuck to turn the final diameter.

First pic shows the blanks (1" diam) all machining to exactly the same length to provide the first reference surface.

Next pic shows the machining of a 1/2" stub, using a saddle stop to provide a reference shoulder, and also something to grab the piston with to turn down the final diameter.


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## steamer (Oct 31, 2010)

Great Start Pat!

Dave


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## pat1967 (Oct 31, 2010)

I turned the OD down of each piston to 25mm OD (final diameter will be 24mm). I mounted the first blank and zero'd against the back vice jaw, and picked up on the diameter to get my centre position for the wrist pin. I used this point as the home position, and zero'd the mill on it so I was set to go when the next blank went in.

The rest is centre drilling, drilling through and final reaming of the hole. Without removing the blank I milled out the first cheek of the piston. Same operations were carried out to the remaining 7


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## pat1967 (Oct 31, 2010)

With the first cheek machined, each piston blank was returned to the vise (machined cheek down) and using a blank drill rod inserted through the reamed hole, ensured the hole was truly vertical.

Vice was locked down, and the second cheek machined. I now have my 8 blanks waiting to be hollowed out (will be doing that bit cnc). The final diameter will be machined after I bore my cyclinders. At least this way I figure the pistons will be all but done.

Till the next installment .. 

Pat


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## pat1967 (Oct 31, 2010)

Thanks Dave,

It's spent long enough in my head and solidworks, definately time to make some chips.

Pat


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## LongRat (Oct 31, 2010)

Pat, this looks exciting. Have you been covering the design etc in another thread? If not it would be great to hear some more background and maybe see some CAD renderings. Also, what's the alloy you have chosen for those pistons?
Cheers.


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## stevehuckss396 (Oct 31, 2010)

Looking forward to watching this one take shape. I am also building a V8 so this one is of particular intrest. With 1 inch pistions I am assuming roughly 1/4 scale?


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## gbritnell (Oct 31, 2010)

Hi Pat,
Nice start on your pistons but I have a question. Why did you cut the side clearance so deep? It doesn't look like it will give you much wrist pin support when you cut out the inside. I know on a full sized piston the side relief seems much deeper but then you're dealing with much bigger diameters.
gbritnell


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## pat1967 (Oct 31, 2010)

LongRat  said:
			
		

> Pat, this looks exciting. Have you been covering the design etc in another thread? If not it would be great to hear some more background and maybe see some CAD renderings. Also, what's the alloy you have chosen for those pistons?
> Cheers.



I will post up some of the renderings. The design started off as the Schillings V8, I drew most of the engine up more than a year a go, but didn't really like the crank design which was a multipart cranks shaft bolted and pinned together. I've remodelled the crank as a single piece and made the adjustments to the block to suit. Also splitting the sump, so that the upper half forms a girdle.

The pistons are being made from 6061 T6 alloy, based on what I've managed to find on the net seems to be a reasonable choice.

I've attached a couple of renderings of the pistons and the crank, conrod, piston, cylinder and block assemblies

Pat 

View attachment SV8-0051.pdf


View attachment SV8-0051-Underside.pdf


View attachment Engine Main Assembly.pdf


View attachment Engine Main Assembly - 2.pdf


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## pat1967 (Oct 31, 2010)

stevehuckss396  said:
			
		

> Looking forward to watching this one take shape. I am also building a V8 so this one is of particular intrest. With 1 inch pistions I am assuming roughly 1/4 scale?



Hi Steve,

It's roughly quarter scale with a 24mm Bore x 22mm stroke, the length of the raw block itself is 162mm (I'd post pics of it, but I've only been game enough to rough it so far so it's a kinda v shaped billet. I want to test my cnc on a lump of wood first before I cut the water water jackets and bores on the real thing).

I've been watching your thread too, all along I was thinking how I was going too find and hold the square billet in V blocks large enough, then saw how you machined the under side of yours using the banks themselves to provide a perfect 45! I used the same method to rough the underside.

Pat


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## pat1967 (Oct 31, 2010)

gbritnell  said:
			
		

> Hi Pat,
> Nice start on your pistons but I have a question. Why did you cut the side clearance so deep? It doesn't look like it will give you much wrist pin support when you cut out the inside. I know on a full sized piston the side relief seems much deeper but then you're dealing with much bigger diameters.
> gbritnell



Hi gbritnell,

I probably could have shyed another millimetre to the wrist pin bosses, as they stand, they are 5mm each in length, the conrods themselves have a bearing area 6mm long. I figured considering each side would only be taking half of the load, the pad should be adequate, it also allowed for a comfortable margin to secure the wrist pin with circlips rather than relying on a press in pin or teflon ends.

It doesn't look so extreme when modelled 

Pat


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## LongRat (Oct 31, 2010)

Very nice indeed.
I really like the look of the Schillings engines - in fact I just placed an order for his book.
What aspect of the pinned crank do you not like? The fact you can use ball races for the main bearings always seemed so attractive to me.


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## coopertje (Oct 31, 2010)

Hi Pat,

Nice project! I have a V8 on my to do list, too bad daily work costs so much precious hobby time... I was wondering about your machining sequence. Are you not afraid that you get cutting marks on the surface of the piston due to the already made cut-outs in the side? In my (limited) experience I get a better finish when there is a constant "load" on the tool. 
Keep the pictures coming!

Best regards Jeroen


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## pat1967 (Nov 1, 2010)

Hi LongRat,

I like them too, you'll enjoy the book, not sure if you can read German or not, but as they say a picture says a thousand words, and provides LOTS of inspiration! For those interested the ISBN is 3-88180-133-2. If you love the Schillings designs a guy by the name of Rolf Luther has developed the design further (I'm striving to build an engine similar to his F1 "inboard", you can visit the website here http://www.luther-modellmotoren.de/

Whilst I do like the idea of supporting the crank on ball bearings, my reservations regarding the original built up crank are based on the fact that I could not envisage myself being able to accurately press fit all the individual pieces making up the crank. So I opted to go with a solid crank, no doubt it will be a long winded machining affair but I don't plan on finishing this motor in a weekend. The other thing is the original crank is a flat plane crank, I wanted a cross plane crank to give that lumpy exhaust note.

Pat


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## pat1967 (Nov 1, 2010)

Hi Jeroen,

Thanks for the comments, work always interferes here too, you're not alone!

I'm not exactly sure how the final machining of the piston OD's will go. The blanks as they stand are oversize by 1mm, and figure on taking several very light passes with a keen HSS bit to bring them to the final OD. Going the other way round and machining the final OD first, in my opinion would be more of a risk of damaging the surface, in my opinion.

Pat


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## pat1967 (Nov 1, 2010)

I got a couple of hours in the garage again tonight  and machined up the wrist pins (no pics of the process, nothing fancy just straight turning). I used some 6mm silver steel, hardened and tempered them. I was a bit concerned about fitting the circlips and being able to remove them if need be (panic on my part) but a quick trial fit on one of the pistons put that to rest.

... Finally some finished parts! 

Pat


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## coopertje (Nov 1, 2010)

Hi Pat,

Nice work on the pistons! The time will learn what the best method is, and probably there are more ways leading to Rome. I normally make the cylinders first, then turn the pistons to meet the cylinder boring because I find it more easy to get an exact measure on external turning then on a internal one (hope you understand my crapy English).

Just read that it will be a Schillings engine, cool! I have the book and the drawings for the 6-cylinder line and V8. I totally agree on the crank design. For the 6 cylinder I made the crank from separate parts, but in a different way. Made steel disks of 12mm wide and 35mm in diameter. In all of them I drilled (and reamed to 10mm) a hole in the center and 3 ones on the correct pitch circle in 120 degrees. From 10mm silver steel I made the crankpins. When assembling the parts I took a long 10mm rod and run it trough the center of the disks to keep them aligned. Then step-by-step I assembled the crack with 648 lock-tide (strength is 30N per square mm!!). When I had it complete I drilled 3mm holes trough the disks and the crankpins and put in a 3mm pin to prevent the assembly from moving incase the lock-tide would not hold.






I do not have a practical experience yet with this construction, only finished the crank and 4 conrods (about 1 year ago).

Looking forward to see your progress! Regards Jeroen


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## LongRat (Nov 1, 2010)

That's a beautiful method Jeroen, I really hope it works. Seems like the easiest method I have seen for making a complex crankshaft.


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## pat1967 (Nov 2, 2010)

Hi Jeroen,

That crank does looks great, would be nice to see some progress on your engine. That design runs in needle bearings doesn't it? I played around with a few different designs too before I decided on the single. Here's what my built up crank would have looked like.

The crank webs are split to allow installing a commercial ball bearing, which eliminates having to harden the "webs". I thought of machining each throw and web halves as one piece, but couldn't work out how to countersink for the bolts, which would be almost equivalent to a solid crank and allow replacement of the bearings if they ever needed it.

Pat


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## coopertje (Nov 2, 2010)

Hi Pat,

Correct, in the original design there are needle bearings. However I find them quite expensive, so mine will be made from bronze. The big advantage is that you can keep them as thin as you like. And I do not plan to run my engine for 100.000km when its finished so I guess bronze will do.

I like your crank design a lot! I think a combination of your design with my mounting method will be perfect. The 3mm pins (to secure the crankpins) will be locked in place by the bearing and you can use the more cheap bearings instead of the needle bearings. I will use the crank I have now for the 6-cylinder, when building the V8 for sure I will use your design (at least if you allow me too).
My 6-cylinder is on hold now, I have some other project running that I want to finish first. I guess I will not be able to restart it within let say one year. 

Regards Jeroen


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## LongRat (Nov 2, 2010)

Excellent Pat, love that crank idea.
To countersink the holes, you could make a countersink tool with a thin shank, that is thin enough to fit through the hole in the opposite web half. Tricky operation though. Or maybe something like a small dovetail cutter inserted in from behind the countersink. The design of the crank would seem to remove many of the difficulties of a normal crank, living with the countersink issue would surely be a small price to pay.


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## aussie bruce (Nov 2, 2010)

Hi there Pat 

Hmm i love your build and have duly subscribed, could you let me know please where you got your plans from? i would love to buy a copy myself as i would love to do a build of a v8 after completion of my Pisces II flash steam engine.

Your solid works model of the crank looks do able have you considered getting a counter bore / sink drill ground up? i usually get them done for work they cost about 60 dollars Aus at the moment they are available off the shelf from iscar but start at 10 mm dia 

For my pistons i have always counterbored the under side and made up a mandrel with a screwed bolt the a dummy gudgeon pin fits through that way i can set the mandrel true screw the piston blank on and then finish turn groove for rings and finish machine the height in one setting 

All the best mate from wet old Melbourne 

Bruce


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## pat1967 (Nov 3, 2010)

Jeroen, Longrat, Bruce

Thanks guys, I'm glad it provided some ideas for you, and you are more than welcome to use it if you like. I did think about making up a custom counter sinking tool with a shaft that screwed into the head. It'd be a bit messy, but would allow assembly in situ and would probably get the job done. Once bored it could be unscrewed and released out.

If I can't pull off the solid crank, I might have to revist it. I plan on machining the crank up before the block, so if it doesn't work out, I'll still be in a position to recover gracefully and save scraping the block.

Thanks for the insight on how you make up your pistons. If you're interested in the Schilling plans, I got mine through VTH in Germany http://www.vth.de/shop/warenkorb/ar...137b378933b11d89908d640.html?cHash=8407db4a24 the plans are a little different from the picture they show. The plans use gears for the valve train, and a kind of primitive fuel injection. I also bought the book through "abe books" http://www.abebooks.com/servlet/SearchResults?isbn=3881801332&sts=t&x=67&y=12

Pat


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## pat1967 (Nov 3, 2010)

Spent some time today lightening up the piston blanks, 4 out of the 8 are done and with it getting late and no mishaps I decided to quit while I was still smiling.

Setup was a transfer to the collet chuck on the lathe to drill a pilot hole for the start of the end mill, and provide a centre reference. I had to doctor a 3mm carbide end mill by grinding a relief above the top of the flutes, since they were 12mm and a needed to go 13.5mm deep into the piston and the shank is actually 1/8".

The blank was mounted in the machine vice, using two HSS bits, up against the reliefs previously cut, and a packing ring below to bring the bottom of the piston above the vice jaws. All went to plan, and will aim to hollow out the remaining 4 by the end of the week.

Pat


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## aussie bruce (Nov 3, 2010)

Thanks for those links Pat looks like i will have to hit the placky card next payday. :big: I have been puzzling over your issue with the crank looking at your model of the crank the image you posted drawn in solid works it would be nigh on impossible to machine those inner webs on the crank is the original design meant to run needle roller big ends? using case hardened linear shaft material? Could you post or email me a pack and go of the solidworks model i usually get an hour for lunch to fiddle with this stuff so maybe able to help. 

Bruce


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## LongRat (Nov 6, 2010)

I just received my copy of the book by Schillings. What a bargain it is, worth the price simply for the pictures and drawings. It looks to be very nice and detailed with some very nice ideas and in general, a 'modern' feel. Looks like he strives to use rolling-element bearings wherever possible, another thing of which I approve. Anyone who doesn't have this should definitely buy it. Firing up Google Translate now...


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## pat1967 (Nov 26, 2010)

Hi Guys,

It's been a while since I've had any progress to post, but managed a few (quite a few) hours in the garage this week, and took the plunge to start lightening up the chunk of 6061 that's to become the cranks case. I had already roughed out the basic V shape and left 0.5mm allowance on the top deck of each bank, just in case.

The machining is all done under CNC on my siege X3.

First set of pics ... 

- What its supposed to look like when finished

- Centre drill at 0.5mm and a manual centre witness (the blued area). I elected to make the first outer most bolt hole the zero, in case I had to go back.

- Centre drilled all holes to a comfortable depth

- All pilot holes drilled, and ready for some milling


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## pat1967 (Nov 26, 2010)

Now for milling of the water jackets. The recesses are 25mm deep in total, with an 8mm dia bottom fillet. I choose to complete the jackets in 2 stages, the first, routing out the shape with a 6mm endmill to a depth of 21mm leaving me the 4mm to machine the fillet in with a ball nose.

It didn't quite work out as 2, it finished as 3 since the ball nose I had only had a cutting depth of about 20mm and the slot cut by the 6mm endmill was slightly undersize. I offset the ballnose on the Z by +10mm and just re-ran the g-code for the bottoming.


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## pat1967 (Nov 26, 2010)

The bit I was dreading, boring the cylinder jackets. I made up a simple plug gauge to the finished bore diameter of 28.00mm, I stepped opposite ends for a short length at 27.90mm and 27.50mm. I fed the boring bar at 0.5mm increments till I got close to the 27.5, then started stepping outward at 0.1 till I got past, but under the 27.9.

The rest of the boring was done at one increment of the boring head dial, then to half increments as I approached the final dimension. You can see the change in chip size from start to finish.

The recess was then finished off with a small clearance in diameter.


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## pat1967 (Nov 26, 2010)

bit up cleanup, and a quick wash with some dish detergent, and I'm a happy chappy, it sort of looks like the model 

Next will be the cleanup of the underside and pocketing for the crank throws.

Enjoy ... Pat


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## pat1967 (Nov 26, 2010)

LongRat  said:
			
		

> I just received my copy of the book by Schillings. What a bargain it is, worth the price simply for the pictures and drawings ...



Glad you weren't dissappointed with, way better value than the plans available for the Schillings engines IMHO.

Pat


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## ozzie46 (Nov 26, 2010)

That block looks great Pat. I am really enjoying this.

 Ron


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## LongRat (Nov 26, 2010)

The block is beautifully finished. Off the meat rack, as we say!
I don't recall reading about the design origins of this engine. Is it your own design, or is it actually from the Schillings plans? I'm not aware of any other plans for a DOHC V8.
I've almost translated the entire Schillings book now. Actually I am wishing it was longer, it is a good read. I have learnt a great deal, but I am a relative model engine novice.


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## stevehuckss396 (Nov 26, 2010)

Very nice work!! I can almost hear it running now!


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## pat1967 (Nov 26, 2010)

LongRat  said:
			
		

> The block is beautifully finished. Off the meat rack, as we say!
> I don't recall reading about the design origins of this engine. Is it your own design, or is it actually from the Schillings plans? I'm not aware of any other plans for a DOHC V8.
> I've almost translated the entire Schillings book now. Actually I am wishing it was longer, it is a good read. I have learnt a great deal, but I am a relative model engine novice.



Hey longrat,

The design is based on the Schilling's engine, my deviations are ...

- Revised lower crankcase half in 2 parts, so there is a girdle integrating the main cap's and upper sump half, and a lower sump which actually holds the oil.
- Cross plane single piece crank instead of the built up single plane crank
- 4 valves per cylinder in lieu of the 2

Pat


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## pat1967 (Nov 26, 2010)

ozzie46  said:
			
		

> That block looks great Pat. I am really enjoying this.
> 
> Ron



Thanks Ron, so far things have mostly gone to plan.

Pat


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## pat1967 (Nov 26, 2010)

stevehuckss396  said:
			
		

> Very nice work!! I can almost hear it running now!



Thanks Steve, you might be picking up on my "vroom vroom ..." noises I make on the way to work 
So far everything has gone well, just finding the time to under take the big tasks like the block has been my issue.

Progress should pick up over the christmas break ... 5 weeks off.

Pat


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## aussie bruce (Nov 26, 2010)

Pat what a lovely bit of work it looks an excellent start mate.

Your cnc X3 lloks like it was well worth the money then do you have a post on it?

Well i am waiting on the arrival from the UK of my book, and after reading all the comments i cant wait to get my greasy mitts on it. 

after reading your comments longrat and pat does the book contain the plans for the basic engine? and if you want the plans you buy them separately from the web site link that you posted earlier Pat?

Vroom Vroom its more of a merc or bm sound mate roooooar ;D

Bruce


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## tonyengines (Nov 27, 2010)

Very nice work!!  ;D ;D ;D I have made a  similar job 2 last years


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## pat1967 (Nov 27, 2010)

aussie bruce  said:
			
		

> Pat what a lovely bit of work it looks an excellent start mate.
> 
> Your cnc X3 lloks like it was well worth the money then do you have a post on it?



Hi Bruce,

And thanks for the encouragement. I converted my X3 about 4 years back now and took very few photos. I bought the standard X3 from Hare and Forbes, rolled ball screws from "homeshopcnc", angular bearings from vxb, and 425 oz nema 23 steppers from Keling. The bearing blocks and motor mounts I machined using my lathe and X2. I'm very happy with it, for the work I do, mostly aluminium, the only rework I have planned for it is to replace the spindle drive arrangement. 2000 rpm for the small 3mm cutters I normally use, makes for slow shallow feeds.

The Z axis is drive through a timing belt at a reduction of 2:1, X and Y are direct drive using oldham couplers. I tried to find some pics for you, but only have a few showing the bearing and motor mounts assembled.

On the book, I can't say there are complete plans, but there are many photos's and dimensioned section drawings through out it, and various valve layouts etc. The engines shown range from Boxers, Twins, V Twins, and V8's. The only unfortunate thing is the text is entirely in German, but longrat seems to have addressed that.

Pat


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## pat1967 (Nov 27, 2010)

[quote Very nice work!! ;D ;D ;D I have made a similar job 2 last years
[/quote]

Hi Tony,

Your engine looks fantastic! Thank you for sharing the pics of it. I would love to hear about any pitfalls or changes you made during the construction, it looks like it was made to the original plans. I love the 4 carby manifold too.

I'm at the point now where I'm trying to decide on materials for the remaining major components, and would like to know what you choose and how you found them in terms of durability.

Pat


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## tonyengines (Nov 27, 2010)

Hi pat
for all the engine -- I to use aluminum 6061 it is fantastic resistant to the temperature (not to deform)

I insert photo of carby manifold


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## LongRat (Nov 27, 2010)

Tony - totally brilliant engine. I'd like to know some more too - how does it sound when running, what is performance like... do you have any videos?
Those contemplating the Schillings book should do it, although on some areas there is a slightly frustrating lack of detailed info (like his fuel injection system for example) there is still a mountain of useful info. The section drawings could be used to get a long way towards a finished engine, while they are not full plans it would only take a little imagination to construct your own plans from them. I didn't realise Schillings was actually a commercial manufacturer in the 70s/80s. Over this time he sold 500+ units of his 40cc I4 and 80cc V8!


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## tonyengines (Nov 30, 2010)

hello 
I have used original plans v8 (with small modifications)and v10 of Schillings

Pat you have construction plans in order to use with CNC ?


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## pat1967 (Nov 30, 2010)

Hi Tony,

I have the same plans that you have in your picture there. I had a friend in Germany do the translations for me to purchase them from VTH on my behalf. 

To build my engine, I've modelled it (about 75% complete) in solid works and generated dxf files for the various cnc operations.


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## pat1967 (Nov 30, 2010)

Time to buy some material ...

I'm looking at the cylinder sleeves and crankshaft and got some quotes today for some 4130 material
- 31.8mm Dia x 3.96mm wt 4130 tube for the sleeves
- 38.1mm Dia 4130 Round Bar

A little pricey, though I'm more concerned about achieving a good finish, and it's durability. I'd rather do it once and be done with it, then have to revist because of worn bores or a twisted up crankshaft. The engine in all honesty will likely never see itself mounted in anything other then a test stand.

Is this overkill? ... Should I be looking at something else?

Open to suggestions ...

Pat


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## tonyengines (Nov 30, 2010)

Pat ......this system is the best one ;D from crankshaft


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## kustomkb (Nov 30, 2010)

Very nice work on your engine Pat!

That block is first rate! Can't wait to see more.


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## pat1967 (Dec 1, 2010)

Thanks Kevin,

Will hopefully be tackling the underside of the block over the next week or so. Although a BAS has got me a little side tracked the last couple of days, but it'll be a few weeks before the test tubes arrive 

Pat


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## kustomkb (Dec 1, 2010)

Ha, Ha. I used the BAS as a break from my long term project too.


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## aussie bruce (Dec 2, 2010)

Hi there Pat 

Cromoly tube 4130 would not be my first choice mate as it is typically drawn over mandrel and has a lot of locked in stress.

4130 solid would not be my choice either its mill finished and typically not available in the annealed variety.

I would suggest either 4140 annealed bar / hollow which is basically EN19a http://www.interlloy.com.au/data_sheets/high_tensile_steels/4140.html

or my favouite 4340 bar which is basically EN24 http://www.interlloy.com.au/data_sheets/high_tensile_steels/4340.html

Or when i can get my greasy mitts on it for special bits EN 26 http://www.interlloy.com.au/data_sheets/high_tensile_steels/en26.html 

But lets face it a nice piece of 4140 does machine very well i like it more than 4130 

Bruce


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## pat1967 (Dec 5, 2010)

Hi Bruce,

Thanks for the suggestions, I'll get in touch with interlloy and see if they will sell me a small quantity. I must admit I have no experience machining this type of steel, the closest thing was machining my ball screws for my cnc conversion.

Pat


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## pat1967 (Dec 15, 2010)

Been a while since updates, so here's where I am ...

I followed Bruce's suggestion and found a local supplier (Edcon steel in blacktown) that would sell me the small quantity of 4140 I was after for the cylinders, that even had no issue with cutting it down into the blanks I asked for, great guys.

Machining the OD's went without a hick up, drilling the pilot bore through is where the fun started. I stepped drilled it 5mm/8mm/10mm/12mm/16mm/22.5mm in 30mm increments (tail stock travel). Small drills went fine, as I increased in size the chips started coming off hotter and hotter and ended up needing to continuously douse the bore with coolant to keep the spirals from turning a pretty blue. Managed to get through all 8 blanks and only had to resharpen the 22.5 drill.

I decided to try bore them to size in the mill, a combination of poor quality brazed carbide boring bars, lack of rigidity, and chatter half way down the bores saw a "rifling" pattern developing. I gave up and chose to move over to the lathe before I scrapped them. I didn't have a carbide insert boring bar, so I used the remnants of a solid carbide 3mm end mill, ground it up to shape and took a light cut through one of the blanks firsts few cuts were a bit iffy, then the continuous little spirals started streaming off. Went through each blank and brought them to size. I've given them a light honing and they feel quite smooth, but the machine marks are still very visible.

Still need to make a plug gauge, and determine exactly how close to each other I have them, before playing around any more on them.

Here's a few pic of the sleeves, in the block, and the blank ...


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## gbritnell (Dec 15, 2010)

Hi Pat,
I'm not posting this as a negative to your build but as some helpful information. 
Sometimes a picture really exaggerates what you're seeing. That might be the case with your cylinder liners. If they aren't totally smooth and parallel you might be in for some trouble. Any little valleys aren't too bad but any small ridges are terrible. 
I would recommend using a solid hone and try to clean them until they are nice and smooth. 
I have always used Schedule 40 cast iron or Durabar for my liners. It machines excellent, holds size well and has the lubricating qualities of cast iron.
gbritnell


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## pat1967 (Dec 15, 2010)

Hi George,

No offense taken and I appreciate your comments. Once I get the gauge machined up and I know exactly how much I have to play with, I'll try honing them clean.

Pat


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## coopertje (Dec 15, 2010)

Hi pat,

I have plans to build a v8 in future. I did some testing with a 4 cylinder block and figured out my own way of working. First I cut the material for the 4 cylinders to length. In the lathe I drilled up to 23.5mm (bore should be 24mm), so I ended up with 4 undersized tubes. I put them on a mandrel and shaped the OD. I mounted the cylinders in the block with locktite and placed the block in the mill. I took a 24mm reamer, started the fluid lubrication on the mill and run the reamer through. The result was amazing, very nice finish and absolute Round boring (I checked with a 3 point micrometer). I found that the trick of using the reamer is to have it swimming in lubrication fluid. For me it's a very easy and convenient way to make the cylinder borings.
Hope it's clear what I mean and keep the pics coming!

Best regards Jeroen


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## Alec Ryals (Apr 29, 2015)

coopertje said:


> Hi Pat,
> 
> Nice project! I have a V8 on my to do list, too bad daily work costs so much precious hobby time... I was wondering about your machining sequence. Are you not afraid that you get cutting marks on the surface of the piston due to the already made cut-outs in the side? In my (limited) experience I get a better finish when there is a constant "load" on the tool.
> Keep the pictures coming!
> ...


 
      Machine tool groves hold oil.


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## Gotty101 (Feb 22, 2016)

Sorry to bring up an old post but I would love to know of any updates. Im hoping to build my own and I have just ordered the book. Although when I went to order the plan it said "unavailable" at http://shop.vth.de/v-8-motor.html

Can anyone help at all?

Many thanks

Trev


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