The Workshop Progress Thread 2019

[JasonBModerator @jasonb]

looking good Jim and I fixed the link for you.

As it is still new and likely to have a few tight spots try a higher pressure but regulate the flow to control the speed.

[Ron LadenParticipant @ronladen17547]

Posted by JasonB on 27/05/2019 16:13:08:

Finally admitted defeat at being able to get my Forest based engine to run as a flame licker. I had always thought that if it would not run that I could convert it to a poppet valve engine much like the Jowitt I made a few years ago. In the end I decided on a cam and follower operated spool valve as I had not made an engine with a spool valve before. Still needs a tidy up and the plumbing sorted out but seems to run at a nice steady pace.

Sorry about the few seconds of compressor noise at about 40 secs in.

A shame it didnt run as a flame licker Jason but it looks to run nicely with the mods. Excuse my ignorance but what is a spool valve and how does it work..?

Ron

[JasonBModerator @jasonb]

Morning Ron

A spool valve works in much the same way as the common slide valve except it is a round valve in a round hole and shaped like a spool or bobbin.

Here you can see that the cam has pushed the spool so that the gap in the middle exposes the air inlet from below and the passage into the cylinder so cylinder fills with air or steam.

In this view the crankshaft and therefore cam have rotated 180degrees so the spool now exposes the passage and the exhaust port which is in the part cut away in the section but is where the arrow shows the flow of exhaust gasses.

[Ron LadenParticipant @ronladen17547]

Morning Jason,

Thanks for the explanation, it looks to be a really neat idea for a valve, I guess it comes from full size engines and possibly dates back quite a few years..?

Ron

[Jim NicParticipant @jimnic]

Thanks for fixing my link Jason.

The engine is, as you say, a bit tight at the moment so will definitely ease a bit with more running. Also as it stands the cylinders and valve chest have no sealing so putting that in will reduce the air leakage and help. Another thing is that one of the return connecting rods is binding on the crank web which is the horrible clunking noise which can be heard which can't be helping with smooth running. There is plenty of work still to do to sort it before I even think about paint but since I haven't got my next project lined up that's not a problem.

Jim

[Anthony KnightsParticipant @anthonyknights16741]

Finished making the bits for Mike Cox's lever feed tailstock.

I've had a few problems on the way. Tried making the feedscrew in one piece with the intention of soldering the 16mm washer on afterwards. Cut the thread with a 10mm 1.5 LH die using a tailstock die carrier and manually turning the lathe over. Some how it didn't quite come out at 1.5mm pitch, don't know why.

So, sawed off the faulty thread and machined the original feedscrew to join it to the other half as per Mr Cox's build instructions.

When I set up the block to drill and bore the 22mm hole, I took special care to ensure the punch mark was properly centered. I was shocked when I offered the completed block up to the tailstock casting to find it was miles out. However, not my fault. It's the 22mm bore in the tailstock which isn't central. Aaargh.

[duncan webster 1Participant @duncanwebster1]

A sorry tale, but here goes: I wanted to make the little angle brackets that hold the slidebars to the motion plates. 5/16 * 3/8 * 3/32 angle. I milled a bit of 25*25*3 down to size and drilled all the holes in exactly the right position. Then I realised that I'd made 2 and I needed 4, so I made another 2. Then it dawned that they are not all the same, so another 2. Clamping the little beggars to the motion plate in the right place was not easy, I must have spent 15 minutes on the first one, spot through, drill the motion plate and find out it had moved. What I then did is what I should have done in the first place, make a long length oversize on the 5/16 where it bolts to the motion plate, drill one off each end, clamp it on, easy now as there is plenty of metal to get hold of, spot through, cut off, clean up the ends, repeat. Finally reduce to 5/16. Dead easy when you've thought it through beforehand

[Anthony KnightsParticipant @anthonyknights16741]

Paint is dry so I've fitted the Mike Cox lever tailstock. First proper project since my illness last year. so I'm pleased it works well in spite of the odd shaped tailstock casting.

[mechman48Participant @mechman48]

Finally got together the material & received the flywheel for my next project; the single cylinder beam engine. Made a start on the flywheel, took some setting up in the 4 jaw to get it to run true to within .005" all round, initially machined the face & boss, drilled shaft bore to 5.5mm to leave drilling / reaming allowance for 6mm later on, next step will be to machine inside of rim at present setting to maintain concentricity …

George.

[mechman48Participant @mechman48]

Picked up the side frames for my beam engine project. Superbly cut on laser cutter in stainless Steel…

[JasonBModerator @jasonb]

With the two crankcae halves that I showed in the KX3 thread milled out they were then faced to depth and bored out on the lathe, one with a recess and the other with a spigot to locate the two together.

I then screwed them together to finish bore the crankshaft bearing hole sin one go to keep all lined up.

Following which a few more holes were added

Then I turned the cylinder to top it off, flange was squared, corners rounded and drilled on the KX3

[JasonBModerator @jasonb]

I made up a jig to hold the cylinder head (see my CNC thread) so that the valve guides could be machined and the seats turned at teh same setting, I always prefer to turn th etapered seat rather than use a CSK type bit and never seem to have problems with valves not sealing.

A few more holes were added and a bit of needle file work removed the contour lines left by the mill

I've also got the gears, tappets and tappet guides done.

Coming together.

[Michael Cox 1Participant @michaelcox1]

Posted by Anthony Knights on 19/06/2019 10:55:09:

Paint is dry so I've fitted the Mike Cox lever tailstock. First proper project since my illness last year. so I'm pleased it works well in spite of the odd shaped tailstock casting.

Hi Antony,

I am glad it all worked out well in the end.

I am intrigued by some of the other things on your lathe:

1. What is it on top of the head stock?

2. What is the yellow object at the top that appears to be resting on the sloping splash guard

3. There appears to be something on the left hand side of the leadscrew before it disappears into the electrical control box.

Sorry if you think I am being nosey!

Mike

[GoCreateParticipant @gocreate]

My 5"g Lion Boiler is progressing, I'm finding silver soldering this mass of copper very challenging but I think I've done an OK job even though some looks a bit messy, soon find out on the hydrostatic test, fingers crossed. Hope to be finished this boiler in a couple of weeks.

The drawings show a square manhole on the boiler dome and I initially machined, drilled and tapped the dome casting accordingly.

However, the loco in the Museum of Liverpool has a round manhole on the boiler dome.

I decided to modify my dome casting to resemble the full size loco. I bored out the dome casting, machined up a ring and silver soldered it in place. One benefit is that I can use a silicon 'O'ring as a seal.

I'll be allot happier when I can get back to machining parts rather than very nerve racking silver soldering.

Nigel

[Jim NicParticipant @jimnic]

A good looking modification Nigel , well done.

Jim

[Neil WyattModerator @neilwyatt]

Nothing more challenging than marking out and drilling a few holes… but I can tell you the correct drill for Fender scratchplate and pickup cover screws is officially a Number 44!

Neil

[Anthony KnightsParticipant @anthonyknights16741]

Hi there Mike. You are not being nosy at all. In fact, I have been a frequent visitor to your web site and done several of the mods and improvements on there.

The red thing which appears to be on top of the headstock is the lid of a plastic storage box in the background. The metal thing actually on the headstock is an angle bracket (I think from some flat pack furniture) which I use as an aid to threading the nuts when changing chucks.

I'm not sure what you mean about the "yellow thing" unless you are refering to the chuck guard which was made from a cut down electrical box.

There is nothing on the lead screw, but I did hear about a problem with swarf entering the electronics box via the hole at the bottom of the box I have therefore built the control circuitry into a fully sealed box which is mounted as shown below. The black plug at the bottom of the box is the supply unit for the washer motor powered coolant system.

[JasonBModerator @jasonb]

With the gears cut for the Midget I could use them to check the PCD to bore the camshaft holes

With that done the holes for the tappet guides were added and then the case opened up to counterbore clearance for the cam lobes

Then I could put it together to see if all fitted

Also made a start on the crankshaft from 35mm EN8, for a change I decided to mill away most of teh waste between the webs rather than the usual interrupted cuts on the lathe.

[Ron LadenParticipant @ronladen17547]

Jason, that was just two crankcase halves five minutes ago, you really do get a move on..

Great stuff.

[JasonBModerator @jasonb]

I got the Midget's flywheel roughed out, easy recessing of the faces using a HSS tool with a roundedend to give that cast fillet look. did most of the width and outer edge with teh lathe running forwards.

Then ran in reverse to do the side of the hub and complete the bottom, both side cuts have the same 3 degree draft angle and no need to reset anything doing it when cutting in both directions.

Some more turning on the crankshaft

Last bit of turning was the taper to take the flywheel cut towards the chuck.

Which then makes it easy to bore the tapered hole at the same topslide setting, using the parts to gauge the fit of the flywheel lengthwise.

It's coming together

[Ron LadenParticipant @ronladen17547]

Certainly is coming along Jason and looking very good. Have you seen the youtube video Midget model engine built from magazine plan I think there are a couple of videos but the one I watched was an American guy inside his workshop and starts by showing the casting patterns he made.

The only thing I think spoils the engine is the rocker arm pushrods which look to be just steel rod bent through 90 degrees, they obviously work but please tell me you are going to do something better than that..

Ron

Edited By Ron Laden on 18/08/2019 21:12:01

[JasonBModerator @jasonb]

Thank's Ron, I think it was that video that first got me thinking of making the engine so I got the 1938 Practical Mechanics Shop notes that had both of the two part article in them. One shows the patterns to make your own castings and the other the construction.

I have scaled it down from 1 1/4" bore to 24mm and altered just about every part in some way but still kept to the basic layout and overall look. As you noted the simple rockers and bent wire pushrods are a bit basic so I have some shapely rockers ( see the KX£ adventure thread) with screw adjusters and the tappets ride in bronze bearings. I will deviate a bit on the carb which is just a plain venturi type on the original by adding a throttle and doing something a bit nicer than the metal pot seen in the video for the fuel tank. As the engine is just for show being able to blip the throttle will be more enjoyable than having it just running flat out and also save it getting too hot while stationary.

Although several illustrations show the engine in a boat hull this one is an interesting use for it and if Michael G. is looking in he will approve of the tool being used. Also shows the basic rocker and rod design.

 

Edited By JasonB on 19/08/2019 07:35:56

[Ron LadenParticipant @ronladen17547]

Good stuff Jason, those adjustable rockers look far better than the plain flat type. I was going to ask about the carb, when watching the video I was waiting for the throttle to be blipped but as you say it is just runs at a fixed speed. A carb with a throttle will be a good upgrade I think.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by JasonB on 19/08/2019 07:25:15:

Although several illustrations show the engine in a boat hull this one is an interesting use for it and if Michael G. is looking in he will approve of the tool being used.

.

What an amazing illustration that is !!

MichaelG.

[Ron LadenParticipant @ronladen17547]

Posted by JasonB on 19/08/2019 07:25:15:

Thank's Ron, I think it was that video that first got me thinking of making the engine so I got the 1938 Practical Mechanics Shop notes that had both of the two part article in them. One shows the patterns to make your own castings and the other the construction.

I have scaled it down from 1 1/4" bore to 24mm and altered just about every part in some way but still kept to the basic layout and overall look. As you noted the simple rockers and bent wire pushrods are a bit basic so I have some shapely rockers ( see the KX£ adventure thread) with screw adjusters and the tappets ride in bronze bearings. I will deviate a bit on the carb which is just a plain venturi type on the original by adding a throttle and doing something a bit nicer than the metal pot seen in the video for the fuel tank. As the engine is just for show being able to blip the throttle will be more enjoyable than having it just running flat out and also save it getting too hot while stationary.

Jason, would I be correct in thinking that the bottom of the rocker adjusters are cup shaped and the push rods will be ball ended to fit inside..?

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