DH Gipsy engine 1/4 scale

What non motorbike related things are you doing, making, building, planning or designing
Dutchman
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Re: DH Gipsy engine 1/4 scale

Post by Dutchman »

Amazing work. :thumbup:
crust
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Re: DH Gipsy engine 1/4 scale

Post by crust »

Wonderfull craftsmanship, thanks for sharing.

:thumbup: :thumbup: :thumbup:
kendo57
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Re: DH Gipsy engine 1/4 scale

Post by kendo57 »

Pistons are relatively simple and firstly turned to size from alloy rod. The ring grooves are cut with
a parting tool, I use a broken piece of hacksaw blade ground to suit, they work really well even on stainless.

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Transferred to the mill the flats are milled and then the gudgeon pin holes are drilled/reamed

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kendo57
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Re: DH Gipsy engine 1/4 scale

Post by kendo57 »

Piston rings , a piece of cast iron is bored and turned to the size of the ring then they
are simply parted off

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One edge of each ring is then snapped buy pressing it over a small triangle file then
they are loaded onto a cast iron crucible / oven.

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The oven lid is screwed shut and heated cherry red

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When the rings are removed the gap is set and the rings have a little 'spring' in them.

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Nordboy
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Re: DH Gipsy engine 1/4 scale

Post by Nordboy »

Honestly, absolute top work. I'm in awe of your skills. I've got no engineering skill anywhere in my body or mind!! :thumbup:
kendo57
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Re: DH Gipsy engine 1/4 scale

Post by kendo57 »

Cylinder heads these start off by cutting some blanks from alloy bar

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First job is to cut the combustion chamber

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Then drill / ream the valve guide holes and open up the valve pocket and cut valve seat.

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Cooling fins are cut the same as the barrels

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there is a lot of machining to form the top of the head , drilling through the exhaust / inlet
ports and tapping mounting holes.

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kendo57
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Re: DH Gipsy engine 1/4 scale

Post by kendo57 »

Forgot this pic ,, the digital level gauge has come in very handy

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Valves are Stainless , I turned about 10mm at a time to help reduce flex in the material.
Also made cutting the groove for the retaining clip more accurate.

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Once I got to the valve head I made a few very fine cuts to size. The lathe tool was set to 45 degrees
and the valve seat angle cut.

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Valve guides turned from Phosphor bronze

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Valve springs are bought from eBay just had to turn the caps and fiddly retaining collets.

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David
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Re: DH Gipsy engine 1/4 scale

Post by David »

Does it run yet gov?
Will we get video with sound when it does?
kendo57
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Re: DH Gipsy engine 1/4 scale

Post by kendo57 »

David wrote: Wed Apr 22, 2020 9:26 pm Does it run yet gov?
Will we get video with sound when it does?
nothing I would like more , not promising just yet though
kendo57
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Re: DH Gipsy engine 1/4 scale

Post by kendo57 »

Inlet manifold , started with a piece of stainless bar

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Milled out the shape and inlet track

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Four mounting stubs out of stainless

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A jig was made and the manifold was set up for soldering

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The stubs are silver soldered in place

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kendo57
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Re: DH Gipsy engine 1/4 scale

Post by kendo57 »

The bottom plate is then soldered in complete with carburettor stub

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A soak in citric acid removes any flux residue and then its polished

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kendo57
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Re: DH Gipsy engine 1/4 scale

Post by kendo57 »

Rocker posts came as a casting and difficult to hold for machining

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The rockers are marked out on a piece of steel bar

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then machined all in one

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They are then cut out and individual machined to shape

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I had to make some castle nuts , luckily these are the only ones on the engine
Ignore the split pin I have since purchased some of the right size

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kendo57
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Re: DH Gipsy engine 1/4 scale

Post by kendo57 »

I made some ends for the push rods , eight rounded and eight concaved

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These are simply loctited on to some stainless rod.

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Horse
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Re: DH Gipsy engine 1/4 scale

Post by Horse »

Brilliant stuff.

And I love your casual use of the term 'simply' :)
Even bland can be a type of character :wave:
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GuzziPaul
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Re: DH Gipsy engine 1/4 scale

Post by GuzziPaul »

Enjoying this. As well as all the close up shots I liked to see an overview of all your tools, mill etc. stuff (and the skill) lots of us can only ream about.
kendo57
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Re: DH Gipsy engine 1/4 scale

Post by kendo57 »

GuzziPaul wrote: Tue Apr 28, 2020 8:43 am Enjoying this. As well as all the close up shots I liked to see an overview of all your tools, mill etc. stuff (and the skill) lots of us can only ream about.
My mill and lathe live in the corner of my garage where I stand and do most of the work . The rest
of my garage has my bikes and usual junk.

This is my lathe , Myford Super 7, its a small lathe generally but considered a large Model making lathe.
Mine was made in the early 1970's ,

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My mill I bought new from Chester machine tools, a rebadged Chinese model but has been very reliable to date.

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kendo57
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Re: DH Gipsy engine 1/4 scale

Post by kendo57 »

Sump , I had already drilled the mounting holes and matched them to the crankcase when I machined
the crankcase.
I then milled the cooling fins

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I then drilled out the hole for the oil feed sump plate

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I turned the oil union and plate from stainless

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Drilling / tapping the mounting holes

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kendo57
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Re: DH Gipsy engine 1/4 scale

Post by kendo57 »

These are the parts plus sump , the oil feed to the crank first passes through the sump.
I can only think this is to keep some heat into the oil supply

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Re: DH Gipsy engine 1/4 scale

Post by iansoady »

It just shows what can be done with what to some people would be fairly basic machinery. I retired my ancient Granville lathe (a cheap copy of a Myford) some years ago when it became too vague for anything requiring accuracy and bought a used Chinese one which has been excellent. Although I don't attempt anything like you do.....
Ian.
1952 Norton ES2
1955 Francis Barnett Cruiser 75.
Sadlonelygit
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Re: DH Gipsy engine 1/4 scale

Post by Sadlonelygit »

We are not worthy!