Here is a list of all the postings Jens Eirik Skogstad has made in our forums. Click on a thread name to jump to the thread.
|Thread: Too large overlap = more high compression?|
Jason, the slide valve was not rotated in 90 degree.
I will check again and find out if the slide covering the exhaust port is shorter or the same length between the two cylinder ports. I'll add more news if there is improvement with the twin compound steam engine.
It is not easy to measure exactly in such small dimensions in the steam machine so I take color on the slide and color print on the cylinder block to find out if it is larger or smaller in relation to the two inlet ports of the cylinder.
The piston are not hit the covers, good clearance between piston and covers. The stroke is correct measured when i created the crankshaft. There is not hydraulic lock there.
I'm thinking if the exhaust is close too early then compression will be too high to get turn over TDC.
Can the length of the slide valve be a bit larger to close a bit sooner to create low compression a bit before TDC? The excenter timing is still correct at 20 degree as in drawings.
Edited By Jens Eirik Skogstad on 07/03/2020 17:22:25
When i started up the compound steam engine, there is not easy to run over TDC both up and down. The piston stop long way from TDC either the piston is in up or down. The steam pressure is high enough 6 bar.
I suspect there is a bit large overlap in the slide valve compared to the valve opening in cylinder block. There is not fault with timing, the excenter is set to 20 degree (i has tried with 0 degree with same result). And the slide valve is centered in right place in both way.
Resolving the problem of reducing overlap by shortening the slide valve a little?
|Thread: Cheap gear cutters from China|
Tried to cut in steel, cutter seem fine. I'm cutting mostly in cast iron, brass and aluminium. Use right rpm and cutting fluid to keep cutter cooled and sharp enough. It's not difficult to resharpen the cutter if worn out.
I has the gear cutter same factory as your gear cutter where there is marked on gear cutter: 上工 (Shàng gōng).
Homepage Shang Gong: http://www.cccme.org.cn/shop/cccme0467/introduction.aspx
Edited By Jens Eirik Skogstad on 29/12/2019 15:54:33
As rule in the dividing plate for indexing head: counts of hole + 1 hole for pin As usual newbeginners did fault when they count the hole with pin in the hole to example 5 hole instead 5 hole + 1 hole for pin at dividing plate for indexing head.
I has a set of gear cutter, Module 1, 0.7, 0.5 from Alibaba, really cheap to buy. I'm satisfied the quality of the gear cutter, precise as i can see when i created the gear wheels.
|Thread: Making a superglue chuck adapter for brass wheel|
Thin workpiece is not easy to turn on 4 jaw chuck. Use the center of the tailstock to center the workpiece who has punch mark or hole before light pressing it into place on the disc and allowing the superglue to dry. Then the workpiece is centered.
I has rings on disc, but the surface must not be polished to get the super glue into the surface and keep better. After the surface is applied with super clue, press the part well on disc then spray accelerator on glue. Then the part is ready to work with lathe. Not in lathe only. You can glue the two parts to example steam chest and cover plate exactly positioned before drill the hole or mill on the side with two parts in same time etc.. then the place of drill hole and size of measure is exactly in both parts.
I've used super glue to hold parts on the self-made flat disc that can't be attached to the chuck. Holds very well without being knocked out by turns from turning tools. Released by heat from torch lamp.
|Thread: Model Turbines|
Mathematics related to steam turbine is not my strong thing. Only practical experimentation with failure and testing results in the creation of a fully usable steam turbine. With the reduction gear you get better use of steam turbine. Heavy turbine wheels + high revolution above 15 000 rpm = better torque due to stored energy in "flywheel". Small turbine wheel diameter is easy to get high revolution than a large diameter turbine wheel for same steam pressure/velocity.
Edited By Jens Eirik Skogstad on 21/12/2019 20:32:33
Deleted due double post.
Edited By Jens Eirik Skogstad on 21/12/2019 20:33:31
Hi Turbine Guy.. see at this link where i wrote about steam turbine. **LINK**
|Thread: Cast iron instead bronce in D valve?|
When I bought the first Stuart steam engine, I was aware that the cylinder / piston was made of cast iron and can rust together. Stuart steam engines are expensive and must be taken good care of. Cannot be compared to toy steamers such as Mamod, Wilesco.
Edited By Jens Eirik Skogstad on 21/12/2019 15:59:56
|Thread: Model Turbines|
Although the horsepower is not high, the horsepower / torque will increase at the reduced speed via the gearbox.See at my steam turbine in this link..
Model steam turbine with 79 mm 4 blade propeller. **LINK**
Model steam turbine with Graupner 65 mm 2 blade propeller (in fault rotation direction) **LINK**
Edited By Jens Eirik Skogstad on 21/12/2019 13:32:01
|Thread: Cast iron instead bronce in D valve?|
I use preservative oil. The steam engine is blown clean for condensed water with compressed air with both drainage taps open and then close the drainage taps so that the steam chest is free from condensation water. Then I add preservative oil and blow through the steam engine as it spreads preservative oil everywhere inside the steam engine. Haven't had rust in the Stuart steam engines.
Good to hear, then i begin to create the D valves of cast iron.
The old cylinder block is repaired after all holes who was misaligned. I used the plugs of cast iron + silver solder without problem. Same with sole plate where all holes are plugged with bronce plug and silver soldered due misaligned holes. I made 2 new steam chests and cover for steam chests of old brake disc (cast iron).
Hi folks, is it possible to use cast iron instead bronce when i am making the D valve for steam engine?
Also i am fix the Stuart compound steam engine with lack of parts and misaligned drill holes etc. (bad work of former owner).
Merry Christmas to all folks.
|Thread: Stuart steam boiler HB4 with roaring chimney..|
I got the message from Stuart Steam models around 4 hour after:
"If the burner is working correctly you should hear a gentle roar from the boiler, you can get various noises depending on how the jet is set up.
Here's how to get the correct burner set up.
Place the burner in the boiler, Start with the jet holder fully pushed into burner, turn the gas on fully and light the gas at the chimney, you should get a flame out of the chimney, then slowly lift the jet holder up from its bottom position in very small increments, fractions of a millimetre at a time, it will get to a point where the flame will disappear inside the chimney and you will hear a slight roar from the boiler, It can be quite quiet so don’t think the flame has got out, by carefully placing your hand above the chimney, without burning yourself you will be able to feel the heat still rising from the chimney, This will be just about the optimum position for the burner, If you go to far you will hear a war war sound, at this point if you push the jet holder down very slightly again this will be the right place for the burner. As the pressure in the gas cylinder decreases you may need to adjust the jet further."
I tried as shown here, but weak heat from burner , do not boil water fast contra consumption of steam.
Who are pleasant to sail steam tugboat with "Pulsejet" to keep boiler heat?
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