new side valve engine fom home made castings

[fourstroke]

Hi everyone

After finishing my "Bill" engine I was scratching around for something to do.
Looking through my collection of engine castings nothing caught my attention but gave me the basis of an idea.

A side valve, single cylinder of decent proportions made from home made castings, big enough to be noticed but within my furnace capacities.

I looked around for side valve pictures for inspiration and took various ideas from different engines to merge them into what you see here. A lot of ideas came from the Westbury model engines book

It took a week or so to finish the patterns, another week to finalise the core pattern boxes and get everything painted. In this past week I have managed to cast two crankcases from seven attempts, the first one was perfect, the next six had various faults till I straghtened them out. Also three sets of the remaining castings for cylinder head, headcover, gear cover, access door plate and front bearing housing. I cant melt iron so have made the first flywheel from bronze for the weight, it took three attempts to get that one right

The engine stands around seven inches tall, has a flywheel of five and a half inches diameter and will have a bore of 36-38mm and stroke of 40mm
( plan A )

Anyway, enough of my ramblings, here are some of the results so far, first the patterns and then some pics of the castings

If all goes well I hope to start cutting metal this weekend and plan to document the build here. It might not be very regular but I hope to keep anyone interested updated with the results, good or bad

Regards

Dougie

 

[Swifty]

Very nice job on the castings.

Paul.

 

[ironman]

Got my attention.
Ray

 

[kvom]

Great start!

 

[charlesfitton]

It looks very Whippet - esque, I like it a lot and will be following.

 

[Gedeon Spilett]

Wow, great start with the castings, nice pictures too, thanks. I did a SV engine last year, smaller , (20 mm bore), it runs now, after I had troubles with the shape of the combustion chamber.
Is your plan already finished ?

 

[BronxFigs]

Interesting process to view on a forum. Totally different patterns from what I thought they would be, e.g....I would have thought the cylinder assembly would be a separate casting, and would be bolted to the top of the crankcase after machining. But, what do I know.

Love it. Good luck with the build. I am sure you will end up with a great little engine.


Frank

 

[deverett]

I admire anyone who undertakes their own casting. It is yet another of those black arts as far as I'm concerned.

Dave
The Emerald Isle

 

[PaPaMitch]

Very Impressive!

 

[fourstroke]

OK
So here is the progress so far
I dont know how to interspace the descriptions in between each picture so I will give the description first followed by the pics

I set ip the casting on the mill using an angle plate set square to line up the base for milling, clamped it and cut the base I also squared the ends of the feet to allow setting it square later

Two pieces of 10x150mm steel were milled square and the two castings were mounted on these, this makes life so more easy when setting up to cut each side
The core holes were filled with wood to mark the centres and the centre for the main bearing was set up using a wiggler, a long home made centre drill was used to start the rear hole for the back bearing, this was drilled and reamed to size. The next job involved using my boring head to cut the casting to size, this was a first for me, I've had the head for a few years but this was its first use, once that was done I cut the internal boss to size measured from the centre line

The casting was set upright and again the boring head was used to cut the central hole and lip for the clinder liner. The casting was finished to size on the cylinder head face

Filpping the casting back onto is side and using the angle plate the inlet face and tappet access face were finished to size and the access hole milled, rotating the casting 90 deg and using a 5/16 packing piece the crankcase access hole was faced and the internal sides milled smooth

The comment that this engine looks very whippet esque is not far from the truth, I took a lot of inspiration from that little engine and the internals on my engine will be very similar, I should also say that I dont work from plans prefering to make it up as I go, I like to keep the design evolving but I have to check myself sometimes as I can get carried away adding this and that till the project never gets completed, I plan to keep this one short(I hope)
Anyway enjoy these pics and I will post more in the next post

Dougie

 

[fourstroke]

The next job was the head covers, these were drilled through the bolt bosses and two holes were tapped 6BA, these holes were transferred onto another piece of 10x150mm plate and the covers fixed using countersunk screws. using this method allows quick clamping to the mill table, the underside was skimmed ant the covers flipped over onto the oposite side of the 10mm plate and a light cut taken over the bolt bosses and water outlet

The covers were clamped to the cylinder head and the holes spotted through and again two holes were tapped 6BA. The heads were scewed to the plate, clamped to the milland the cylinder side was faced, both heads were flipped over and cut to finished size

Any comments or suggestions will be very welcome
Regards
Dougie

 

[Terryt]

Hi:

A great job. I am enjoying you progress very much.

Would you share with us that do not know how to make patterns on how or where to look for advise?

Thanks,

Terryt

 

[bmac2]

Hi fourestroke (Dougie)
Love the patterns. The castings look great. It was thoughts of making a (as charlesfitton put it) Whippet-esque engine that got me to take the plunge into casting. So Far I’ve done about 6 hours of pouring metal and 6 months of reading. I figure another 6 months of reading and I might be ready to start. Keep up the good work I’ll be following along.

 

[fourstroke]

Hello again
I made some progress on the engine that I wanted to share and I also hit my first snag, details to follow

After finishing the cylinder heads to height I clamped the first one to the main casting and spotted through to mark the stud positions, the same with the second. The first casting went smoothly drilling the holes into the top face, the second was going well till the drill hit a hard spot, probably a bit of slag and wandered off to the side, not by much but enough to mess up the spacing. My solution after a bit of thought was to centre the offending hole on the mill and using a solid carbide cutter I cut through the hard spot to leave an 8mm hole. This was filled with a bit of aluminium bar secured with loctite, once it cured the hole was re spotted, drilled and all the holes tapped 4BA, the head was given a light skim to level it off

The next thing was to cut the water space slots to allow the water to circulate . The edge of heads were cut back to get to the correct wall thickness in the areas required then both of them were marked out and milled. These areas were copied onto the top of the main casting and slots milled to match the ones in the head

The clinder head and top cover casting are both a bit oversize so they were clamped to their respective casting and marked to size then ground back to match the main body casting

The next picture in the list shows the gear train to operate the cams, these are 0.5 module, 25,30,30 50 teeth respectively, the 25 tooth gear needs to fit on the reduced diameter of the rear portion of the crank which will be 1/4", the boss is 6mm as supplied so I had to make a bush to attatch to the gear that will allow the fitting of a grub screw to secure it. This bush has a tight fitting 6mm hole to fix it centrally to the gear and then the two were silver soldered together, once it was cool and had been cleaned in the pickle the central hole was opened up to 1/4"

I hope you enjoy these pics, there are a few more in the next post along with an answer to the question about pattern making
Dougie

 

[fourstroke]

The first picture in this next set shows the bearings for the rear section of the crankcase, these are 13mm OD x 10mm ID and 25mm over the flange, the flat is to collect oil and direct it to the hole into the bearing, most of the lubrication will be by splash but I plan to design an oil pump worked from the rear crankshaft, thats what the boss under the rear bearing hole is for, again, plan A.
The next is the start of the machining of the front main bearing, this is as far as I got tonight as I need to give it some thought as to how to procede

The next picture is in response to the question from Terryt about pattern making, its the very first pattern I ever made and it was the base for a twin cylinder vertical steam engine. I was fortunate enough to go to school at a time (1970's) when the metalwork class had a forge and a furnace and the teachers wern't afraid of being sued if me or someone else went home with a hole burnt in their clothing or a cut from a bit of swarf. I got the basics about casting there when one of my classmates cast a set of "trucks" for his skateboard. the picture shows the one important thing about pattern, they must have "draw" angle built in to allow them to be removed form the sand, I used this picture as I went overboard with the draw angle but you get the drift.
There are more knowlegeable people than me on here who can probably tell you the rules but in my case all I do is make sure that each pattern has enough bulk to allow metal removal where required, I dont worry about shrinkage, if I make all the patterns to the same size then they will all shrink at the same rate I assume.
The patterns are made from whatever comes to hand, plywood and MDF usually. The fillets around the corners are auto body filler which is easy to smooth before it sets with a little cellulose thinners, the paint is high build primer, again from the car spares shop, if its a split pattern then the most important thing to remember is to fit the register pegs at the start of the build.
My furnace is homemade as are the casting boxes, an empty butane cylinder cut and lined is the main body, the picture shows the first melt for this engine, the flames are from the old oil still sticking to the aluminium, it was an old engine crankcase I cut up, I would normally do this outdoors but it was blowing a gale and raining heavilly, the one thing I have learnt is that molten metal and water definately dont mix
Regards
Dougie

 

[gbritnell]

Excellent work on your engine, especially the castings.
gbritnell

 

[stevehuckss396]

Cool build so far!!!

 

[BronxFigs]

Very interesting to witness the birth of a new-and-improved version of the "old-style" Whippet-ish engine. A lot of hard work and considerable thinking went into this project. I wish you well.

Frank

 

[fourstroke]

Thanks Frank
I spent all of today trying to machine the front bearings concentrically with the crankcase register, it should have taken less than an hour
I didn't put enough thought into the bearing casting, the chucking piece should have been on the front face of the casting, that would have let me bore the hole for the bearings and machine the crankcase register at the same time, the solution involved various mandrels and a holder machined to sit the crankcase register in

Hey ho, thats what I get for winging it

Dougie

 

[bmac2]

Hi Dougie
That’s one of my mysteries solved. The boss under the rear bearing hole is for an oil pump. That only leaves the 2 at the top . . . . Radiator mounting? Fuel tank? Water pump?
I’ve just started casting some practice patterns I made up so is going it’s going to be a while before I can get started on the 10cc version.
Thanks for posting this build.