Member postings for Jim Nic

Well, it's only taken me a month or so but some progress has been made. The cylinders as drawn are made as a 1 piece aluminium tube with squared ends and a cast iron liner.

Looking at materials I had to hand I made mine as the ali tube, separate end flanges and the cast iron liner:

Since my engine will only ever run on air the parts were assembled using Loctite 638 which I have very confidence will hold.

Next will be the cylinder heads, which are straight forward, and the crankcase breather then I can look at the crankshaft and its housing.

Jim

Edited By Jim Nic on 14/07/2022 15:44:30

If the organisers are adamant that the show will go on then I am adamant that I'll be there. Careful driving in my Honda Jazz should see me the 30 miles there and 30 home for about 6 litres of petrol, not so much of a problem for me as for folk with farther to travel and a significant cost in fuel.

I'll look out for you Noel.

Jim

Another beautiful result Jason. I think that a good test of a stationary steam engine is how well it runs at slow speed and this one certainly is a smooth runner. Well done.

I always follow your builds and usually pick up a tip or two to help me to hopefully match your standard one day. Thanks for your postings

Jim

Definitely get a milling vice. A totally different beast to the drilling vice you are using now and will help you to get more accurate results quicker. A rotating base vice is not necessary, in 12 years modelling I have used my rotating base just once and its not even thick enough to use as a doorstop in the workshop so if I knew then what I know now I could have saved a bit.

Jim

Edited By Jim Nic on 23/06/2022 18:29:27

Another option is tape/video recoder drive belts which are flat rubber and thus a little more realistic. Packs of varying sizes are available from that renowned on-line auction site.

Jim

At £85.00 for just the 5l of the blacking, never mind the preparation copmpounds, that stuff from Blackfast would seem to be ruled out by Rik's proviso that the process needs to be done "a la cheapskate"

Jim

Having completed the Norden engine and cleaned the workshop I was at a bit of a loss looking for an interesting follow up. Scrolling through the Mad Modder site I came upon the very thing, a 3 cylinder radial single acting engine. Originally designed, I believe, by Edgar Westbury as the Cygnet Royal and subsequently simpified by Elmer Verburg. This version is an amalgam of both designers thoughts put together by Stew Hart.

This is Stew's engine and what I am aiming for.

To kick off I took a piece of aluminium bar:

And removed most of the metal from it until I was left with this:

For scale the flats on the hexagon are 25.4mm wide.

The next opportunity for me to make a mistake is the 3 cylinders and their cast iron liners. Wish me luck.

Jim

Edited By Jim Nic on 11/06/2022 21:34:33

All well and good advice Brian but you don't get the package to enable you to check such things until after you have coughed up the supposed shortfall and the surcharge.

Jim

Thanks Jason. Having an interesting colour scheme is the only way I can persuede the domestic authority to allow my engines in the house. (I may not be the boss around here but at least I'm second-in-command)

Jim

Here at last my complete and painted Norden engine. It has been an interesting build which kept me amused for a bit longer than I anticipated. However, it now runs reasonably well and looks good sitting on the shelf.

And here's a vid of the engine running. 

Edited By Jim Nic on 03/05/2022 12:20:29

Edited By Jim Nic on 03/05/2022 12:25:46

Edited By Jim Nic on 03/05/2022 12:27:17

Edited By Jim Nic on 03/05/2022 12:28:52

A good project well completed. Thanks for the story and the pictures. Thanks also for the description and cad drawing of how a slip eccentric works, we're never too old to learn are we.

Jim

Nigel B

Although Machine Mart still have the 3 in 1 machine in their on line catalogue there is a note at the top of the advert that says "Sorry. This product has now been discontinued."

Jim

Good progress there Derek. Its starting to look like it may be a loco.

Jim

Hi David

As Jason has found it was indeed in ME, I picked it up from Neil's later piece in 2014.

Mine differs from Neil's drawings in several respects. Firstly castings are no listed as available and since I was therefore making it from bar stock I altered the original imperial dimensions to metric at 1mm to 1/32". It is also less complex in that the conrod bearings are not a wedge arrangement and the flywheel and other crankshaft mounted parts are not located by slot and keys. Finally, after a couple of attempts to get it functioning, the governor valve is a complete dummy.

Jim

Another phase of my Norden engine complete. The initial build is done with a couple of temporary bits and pieces to get it ready for a first run

And, hopefully, the run:

At the moment there are no seals in any of the joints or glands and no piston seal so air is leaking from everywhere.  Hopefully when I reassemble it after painting it will be a bit quieter and run a bit smoother

Jim

Edited By Jim Nic on 02/04/2022 20:50:59

Edited By Jim Nic on 02/04/2022 20:51:32

Edited By Jim Nic on 02/04/2022 20:54:32

A fine looking and interesting model George. Good luck with finding the knock. I once had an engine with a similar problem which wasn't apparent when turned by hand, only when running; found the bugger in the end but it took a while. The design of the Scotch Yoke seems to me to be set up for a knocking noise as it changes from "push" to "pull" on the crank, there must be some clearance for the pin to slide in the slot after all.

Jim

Roy

Perhaps a good place to start would be to try and estimate what your model needs for it to run. You have already had it running so you know what pressure it requires to run to your satisfaction.

The other thing you need to know is what volume of air you need. You can work this out if you know the dimensions of the model's cylinder; from this you can work out the volume of air you need per revolution (twice the volume of the cylinder) and from this and the speed you wish it to run at the amount of air you need. Compressors normally have what is known as Free Air Delivery in their specification which is the amount of air it is capable of giving you.

From all this, you can look again at available compressors.

Hope this helps

Jim

I think that the "problem" , if indeed it is a problem, is that people coming in to the hobby today do not come from the kind of engineering background that many of us oldies do. The difficulty with Google and the like is knowing what question to ask and then understanding the answer, particularly if it involves a U-tube video which may or may not give correct advice.

In my opinion there are fewer members on here with extensive model engineering expertise than when I started 12 years ago so the pool of knowledgeable people willing to answer questions is reducing which of course increases the "workload".

We should be open and welcoming to beginners, as most of us are, after all we need the younger folk to continue the hobby and keep our suppliers going for the benefit of us all. If we do not like answering what we consider to be basic questions then we need not respond.

Jim

Hi Stew

Thanks for the comment. I like making your designs and always try to do justice to them.

I have never run any of my engines on steam; I know it would be a good thing to do but many of my earlier efforts have been assembled using adhesive where silver solder would be required for steam. Maybe one day a boiler will come to the top of the "round tuitt" list.

Just for interest here is a pic of my "Stew Hart Collection".

Jim

Gerhard

You say you use DW40 as a cutting fluid. If that is a misprint and you meant WD40 then that is a problem. WD40 is a water displacing lubricant consisting of a grease held in a light solvent and is not designed for high pressure situations such as tapping.

In any event, for small threads you need a tapping compound such as Trefolex as mentioned above or I use a liquid called CT 90 which not only helps to cut clean threads but has saved me a fortune in broken taps.

Jim