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Re: DH Gipsy engine 1/4 scale
Posted: Thu Apr 16, 2020 9:25 pm
by Dutchman
Amazing work.

Re: DH Gipsy engine 1/4 scale
Posted: Fri Apr 17, 2020 6:29 pm
by crust
Re: DH Gipsy engine 1/4 scale
Posted: Sat Apr 18, 2020 2:18 pm
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.
Transferred to the mill the flats are milled and then the gudgeon pin holes are drilled/reamed

Re: DH Gipsy engine 1/4 scale
Posted: Sat Apr 18, 2020 2:28 pm
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
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.
The oven lid is screwed shut and heated cherry red
When the rings are removed the gap is set and the rings have a little 'spring' in them.

Re: DH Gipsy engine 1/4 scale
Posted: Sun Apr 19, 2020 8:00 am
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!!

Re: DH Gipsy engine 1/4 scale
Posted: Wed Apr 22, 2020 8:15 pm
by kendo57
Cylinder heads these start off by cutting some blanks from alloy bar
First job is to cut the combustion chamber
Then drill / ream the valve guide holes and open up the valve pocket and cut valve seat.
Cooling fins are cut the same as the barrels
there is a lot of machining to form the top of the head , drilling through the exhaust / inlet
ports and tapping mounting holes.

Re: DH Gipsy engine 1/4 scale
Posted: Wed Apr 22, 2020 8:53 pm
by kendo57
Forgot this pic ,, the digital level gauge has come in very handy
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.
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.
Valve guides turned from Phosphor bronze
Valve springs are bought from eBay just had to turn the caps and fiddly retaining collets.

Re: DH Gipsy engine 1/4 scale
Posted: Wed Apr 22, 2020 9:26 pm
by David
Does it run yet gov?
Will we get video with sound when it does?
Re: DH Gipsy engine 1/4 scale
Posted: Sat Apr 25, 2020 7:06 pm
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
Re: DH Gipsy engine 1/4 scale
Posted: Sat Apr 25, 2020 7:15 pm
by kendo57
Inlet manifold , started with a piece of stainless bar
Milled out the shape and inlet track
Four mounting stubs out of stainless
A jig was made and the manifold was set up for soldering
The stubs are silver soldered in place

Re: DH Gipsy engine 1/4 scale
Posted: Sat Apr 25, 2020 7:20 pm
by kendo57
The bottom plate is then soldered in complete with carburettor stub
A soak in citric acid removes any flux residue and then its polished

Re: DH Gipsy engine 1/4 scale
Posted: Mon Apr 27, 2020 8:01 pm
by kendo57
Rocker posts came as a casting and difficult to hold for machining
The rockers are marked out on a piece of steel bar
then machined all in one
They are then cut out and individual machined to shape
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

Re: DH Gipsy engine 1/4 scale
Posted: Mon Apr 27, 2020 8:04 pm
by kendo57
I made some ends for the push rods , eight rounded and eight concaved
These are simply loctited on to some stainless rod.

Re: DH Gipsy engine 1/4 scale
Posted: Tue Apr 28, 2020 5:17 am
by Horse
Brilliant stuff.
And I love your casual use of the term 'simply'

Re: DH Gipsy engine 1/4 scale
Posted: Tue Apr 28, 2020 8:43 am
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.
Re: DH Gipsy engine 1/4 scale
Posted: Wed Apr 29, 2020 9:38 pm
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 ,
My mill I bought new from Chester machine tools, a rebadged Chinese model but has been very reliable to date.

Re: DH Gipsy engine 1/4 scale
Posted: Wed Apr 29, 2020 9:46 pm
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
I then drilled out the hole for the oil feed sump plate
I turned the oil union and plate from stainless
Drilling / tapping the mounting holes

Re: DH Gipsy engine 1/4 scale
Posted: Wed Apr 29, 2020 9:49 pm
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

Re: DH Gipsy engine 1/4 scale
Posted: Thu Apr 30, 2020 10:56 am
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.....
Re: DH Gipsy engine 1/4 scale
Posted: Fri May 01, 2020 10:13 am
by Sadlonelygit
We are not worthy!