Here is a list of all the postings PatJ has made in our forums. Click on a thread name to jump to the thread.
|Thread: Special nuts for various parts|
I keep hex stock on hand of various sizes, and then just drill it, tap, and part off to the desired length.
Saves a lot of time if you have to make a significant number of fasteners of various sizes.
I make bolts and nuts from this material.
Edited By PatJ on 05/03/2021 07:28:51
|Thread: Inherited ML7 in need of some love - where to start?|
Don't get aggressive with cleaning the ways; they are precision items.
A few more reduced size brochures which I found helpful for identifying parts, pieces and accessories.
I would say be very methodical and clean one piece at a time.
I use a fine sanding sponge or buffing wheel to clean up surfaces sometimes, and that works well in a drill or tool and die grinder (tool and die grinder is limited to a 2" diameter sanding sponge).
The parts need to be oiled immediately after they are cleaned to prevent rust.
Here are some reduced samples of the material I have.
I have a lot of original brochures that explains every part on the Myford 7, and explains the various accessories that can be used with it too.
Edited By PatJ on 03/03/2021 07:07:51
Mine came with quite a few accessories, but more importantly it came with full documentation.
The scans of the documentation are large.
I will try to upload a reduced sample here.
If you PM me, I can probably set up a file transfer for the documents that I have.
I think you would find them very useful.
I bought a Myford a few years ago, but have not had time to use it.
I have been snowed under with work projects literally for years.
I keep in a humidity-controlled environment to prevent condensation on the bare parts.
With some TLC, yours can look like this again.
|Thread: AutoCad 2000 Query|
You could perhaps set up a drawing that contains one dimension set up the way you want it, and save it as a separate drawing.
Insert that drawing as a block into your new drawing, and use the matchproperty command to match your new dimension to the style of the one you set up previously.
I have not verified this with dimension styles, but I have used it with other things such as symbols and such.
|Thread: disappearing forum archives|
I tried the "save page as" and used the html format, and it did indeed save this page, complete with all the blinking adverts and such (LOL, some things work too well), and it is identical.
I unplugged my network cable, and opened the html file that I saved, and the page appears perfectly without being connected to the internet.
I use firefox, and there is a pulldown box on the upper right to access the "save-as" comand.
I will attach screen captures of the pulldown box, and of the image that appears on my screen without being connected to the internet. You can scroll up and down on the page created just as if you were online, but you cannot post anything to it, at least I don't know how to add to an offline html file.
Edited By PatJ on 01/03/2021 05:55:33
Edited By PatJ on 01/03/2021 05:57:10
I have saved some forum pages in the past, and the "save pdf file" option does not work consistently, often either distorting the page, or truncating it prematurely.
Another option I ran across recently is to save a page as an html file.
An html file is created, as well as an accompanying folder, which must remain together, and used as a unit.
If you open the html file, the web browser will open an identical forum page, complete with all the photos, even if you are offline. I have not tried this yet with this forum.
And an added bonus is that within the file folder is all of the jpg photo files.
This is a great option for me, and it reproduces an exact copy.
I will try it here and see if it works.
I have ordered quite a few things from McMaster-Carr, and they give good service.
And I have used a lot of their 2D and 3D models that can be downloaded for many of their parts.
Never had a problem with them (I am in the US).
I have ordered things from the UK, mainly such as books, but also some equipment, and had good luck with that too, but it takes a while when you cross borders, and a VAT-type fee generally will kick in one way or another.
|Thread: Silver Soldering help - crankshaft|
There is definitely a bit of an art to silver soldering.
Using a good flux is critical, as is cleaning the metal before applying the flux.
I have only silver soldered a few items, but all were successful.
I have done a lot of soft soldering, and so the technique is the same, but with a lot more heat.
The art is to get the metal hot enough without burning up all the flux.
You have to get the overall part pretty hot, and then focus on one joint at a time to bring it up to the wicking temperature. There is a certain sweeping motion required to spread the heat a bit on the joint. You don't want to create a hot spot on the joint that will overheat the flux.
It takes a very surprising amount of heat to get the metal up to the temperature where the silver solder will wick, and for that reason I don't like to silver solder things, just because refilling the oxygen and acetylene bottles is expensive.
I generally use a shaded welding goggle when silver soldering due to the brightness.
If you are not seeing a wicking action starting on the surface, then the metal is not hot enough. Don't feed in the silver solder if the wicking action has not started, else you get the cold blobs.
Without a clean joint and good flux, and sufficient heat, there is no wicking, but rather just blobbing on the surface, which has very little strength.
The strength in a silver solder joint relies upon having a thin joint, and a completely wicked joint.
Thick silver solder joints are not nearly as strong as thin ones.
I am no silver solder expert by any means, but I can successfully solder with that material.
Too much clearance and the joint is not as strong as it could be.
Too little clearance and the joint may not wick.
I have seen some folks cut a step on the end of the pins, which they fill with silver solder.
A step would work, but a longer thin step would be stronger.
Pinning the crank will take the solder joint out of shear, so the solder is basically to keep things from moving, and not so much for strength.
And keep in mind that many motorcycle crankshafts are pressed together without any soldering or pins, so from that respect, I would say the pins are probably not necessary.
Certainly on a model engine operating under no load, the stress on the crank would be very minimal, and silver solder alone is probably overkill.
For a launch engine operated for a considerable amount of time under full load, you would have to pay much more attention to the crankshaft.
Edited By PatJ on 26/02/2021 16:05:11
Edited By PatJ on 26/02/2021 16:06:50
Edited By PatJ on 26/02/2021 16:07:40
Edited By PatJ on 26/02/2021 16:09:33
Edited By PatJ on 26/02/2021 16:11:02
|Thread: Condenser Cooling water flow|
Definitely on the other end of the spectrum from where steam engines were in 1920.
Predates the screw propeller (The Mississippi used paddlewheels).
I am told that this was the first attempt to mechanize a US ship with a steam engine, and it did appear to be a functional ship, which sailed/steamed all over the world.
It was the first and only side beam (lever) steam ship the US Navy ever built, and so that makes it rather unique too. It seems like they took a sailing ship design, carved out the center, and dropped in two very large engines and a bunch of boilers. Sort a shoe-horn affair it would seem, but apparently a successful attempt.
I was quite surprised when I read that they used sea water in the boiler.
The frame is Gothic style, and so is rather a pain in the rear to model in 3D, but I am getting there.
But I saw the post title, and so decided to try and learn more about condensers.
Edited By PatJ on 25/02/2021 05:06:00
Edited By PatJ on 25/02/2021 05:06:44
Edited By PatJ on 25/02/2021 05:07:34
Everything you mention sounds reasonable.
I guess when you consider that science class experiment where they would introduce steam into a flexible container, and then submerse the sealed container into cold water, and it would collapse.
So the vacuum force would be generated without an air pump, and my guess is like you mention, the air pump just removes excess air and condensate.
Here are a few items I found in some old books.
The Mississippi condensers were jet condenser type.
I hope I am not cluttering up or hijacking this threat too much with all this.
Edited By PatJ on 25/02/2021 02:05:49
Edited By PatJ on 25/02/2021 02:07:46
Here is the information on the Mississippi steam ship.
This data mentions 12 psi, which is even lower than I stated above.
Constructed around 1840, using a copper boiler I think.
Boilers in 1840 were apparently rather crude from a standpoint of withstanding very much pressure.
I am reverse-engineering the Mississippi steam ship side beam engine, and noticed that it has a condenser and air pump.
I have read that at such a low steam pressure (I think 18 psi), the condenser is required in order for the engine to operate and develop usable power.
The steam cylinder is 75" diameter, and the air pump is 46.5" diameter, so a 2.6:1 ratio as far as surface area.
It would seem that the air pump would use a significant amount of power to operate, but perhaps not.
I am not sure exactly what pressure the air pump piston has to work against, but that would determine the power used by the air pump.
I noticed there is a foot valve, so the air pump only has to move air and condensate past that foot valve? and then gets pumped back to the boiler, or pumped overboard by another forced pump?
I am new to condensers, especially of this old style where there was a jet of water forced into the condenser chamber, and no separation via the tubes commonly seen in more modern condensers, so trying to understand more about them.
Edited By PatJ on 24/02/2021 23:45:35
|Thread: What Did You Do Today 2021|
Working on 3D models for the steam ship Mississpppi side lever engine, with hopes of one day casting one.
Proposed beam is 24" long.
Go big or go home as they say.
Edited By PatJ on 19/02/2021 21:43:33
|Thread: A Marine Condensing Engine|
I seem to recall someone attempting to cast this engine.
If the 3D models are available somewhere (seems like I saw them online), then they could be used to 3D print patterns, from which castings could be made.
This is a great looking engine, and I have admired it for years.
The build for it in this thread is looking very good, and much like castings.
With parts that look that good, who needs castings ?
Edited By PatJ on 19/02/2021 20:09:51
|Thread: 3 HP Frisco Standard Stationary Single 4-Stroke IC Engine|
We do have rivers nearby, so I guess we can drink river water.
I have filters that I use for backpacking.
I guess it would be best to get water from above the local wastewater plant discharges.
This has sort of become a storm update post, sorry about that.
They are discussing shutting down all water in this city.
The infrastructure was not designed for 1 F temps, and they are describing the damage to the water system as akin to what a major earthquake would do.
They are calling in the national guard to bring water to hospitals.
I told my wife we can always melt snow and drink that.
She said "The snow is suppose to melt tomorrow".
Ruh rho !
We got trouble.
In the early days of forums, I am guilty of straying a bit sometimes and posting political or other perhaps not appropriate things on forums (not this one).
Live and learn as the say.
These days, when I post, I ask myself (before I hit the SEND button):
1. Is this post appropriate if my grandmother were to read it?
2. Does this post help others, and advance the state of the engine modeling hobby?
3. Is my post diplomatic, and make its point without sounding harsh and aggressive?
4. Does my post put things in a positive or negative light? Its the question "Is the glass half full or half empty".
I like to be on the "half full" side.
5. Am I bored and just trying to use up time, or should I get out into the shop and do something productive, and then post about that work?
In the end I think we all want to feel good about ourselves, offer support to others when we can, and make this hobby the best we can.
I wake up every day and try to do things that make this world a better place.
We all have that opportunity every day.
Edited By PatJ on 19/02/2021 17:43:43
Edited By PatJ on 19/02/2021 17:44:24
Edited By PatJ on 19/02/2021 17:44:49
Edited By PatJ on 19/02/2021 17:45:27
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