Stuart 5a stationay build

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Hi GreenTwin. Thanks.


Time to start final assembly. First take everything apart and clean in acetone. Mask and paint. This #5a is in gloss black. Stuart traditionally uses an olive drab green for the upper part of the engine and black for the base. I think gloss black looks great. Start assembly.





Final Assy 1.jpg






For gaskets, I used heavy paper soaked in steam oil. Our son has a 10-watt laser attachment for his 3d printer. I drew up the gaskets in FreeCad and had him cut them out with the laser. They came out perfect. They look like scissor cut.





Final Assy 2.jpg






I am horrible at sheet metal work. As for cylinder cladding – just get it done. Since the eccentrics are keyed to the shaft there is no adjustment. They either work or they don’t.





Final Assy 3.jpg






The plan for the valve rod fork is totally wrong. Making the fork according to the plan will bind and foul the radius link. There is no way to fix it, just make another. Add a full 1/8”.





Final Assy 4.jpg






The valve is set on the valve spindle by a pair of opposing jam nuts. The photo below shows a length of thread on the bottom portion of the valve rod and none at the top. The top jam nuts are fully engaged, just can’t see any thread. The valve spindle is the correct overall length, but it may be a good idea to shift the threaded portion up about 1/8”





Final Assy 5.jpg






Next time is the finish up and air test.





Take care, Bob
 
Thank fellas.


Well, this is it. Last of the assembly. Get this 5a running on air today. The plan does not specifically show a locking nut for the shifter arm. There is one part on the plan that did not have a clear purpose. Maybe it was the locking nut, I just could not figure out how it worked. Anyway, this locking nut requires square ends on the drop arm.





Final Assy 6.jpg






There is a bracket attached to the valve chest that holds a pivot. Like the rest of these parts, it’s a brass and silver solder fabrication. The shifter arm and bell crank arm (I don’t know what these parts are called) are fixed with tapered pins. The pins are size 5/0. One pin is drilled, and hand reamed in place. For the second pin, tap 2 x 56 for adjustment. Use a sharped 2 x 56 machine screw for adjustment. Once everything is in place, sinch the screw tightly to leave a witness mark on the pivoting pin. Drill thru and hand ream. Everything fell in place on the first try.





Final Assy 7.jpg






And here’s the prom photo.





Final Assy 8.jpg






Set up for an air test. Oil everything up and let it go. It runs good on about 12 PSI. Runs great on 20 PSI. It screams at 30 PSI.











That’s going to wrap it up for now. The engine needs some better cylinder drains, a mechanical lubricator and a 4-line gravity feed oiler for the standard and main bearings. That will come along in a bit. Going to add the three more features suggested by a friend: drain on the valve chest, a flat on the valve spindle and a threaded plug on the top cylinder cover.





Thinking about putting this engine on a two-seat go-kart. Wood frame, metal frame gussets, spoked bicycle type wheels. Make it look really old school. My wife can steer, I’ll run the boiler and engine. In these parts everyone drives ATV’s all over, don’t think the sheriff will mind a steamer.





I want to thank everyone who checked in and commented during the build. Thanks again. The next stationary is a Stuart Beam, that will probably start in the fall.



Take care, Bob
 
Your a very good machinist, the 5A is a nice size engine. Well done.
 
When you have the plans, discuss with a club boiler inspector to gain advice on manufacture, and his confirmation that he will accept a boiler made to the plans for testing. Otherwise you may have a boiler he won't test or doesn't meet today's regulations. (Which is why I have converted 2 boilers recently to increase their strength to be able to be certified!).
I think most Martin Evans designs are still accepted in the UK. If you need calculations, I can do them for you, but would need to know the regulation limits relating to the certification as well. I have ASME and recently found a link to various States regs. I shall look-up regs for South Dakota...
I don't charge for doing the sums. - just message me personally if you need it.
K2
PS: A clause (Below) may mean you do not need a Test and certification: CHECK WITH the regulator: That's something I can't do for you. He may want a copy of the boiler plans. To have a letter from him saying "you don't need a certificate" is very valuable! - If you can get one.

34-29A-26. Inspections required for operating boilers--Frequency of inspection.

Each boiler used or proposed to be used within this state, except boilers exempt under § 34-29A-14, shall be thoroughly inspected as to their construction, installation and condition as follows:

(1) Power boilers and high pressure, high temperature water boilers shall receive a certificate inspection annually which shall be an internal inspection where construction permits, otherwise it shall be as complete an inspection as possible. Such boilers shall also be externally inspected annually while under pressure;

(2) Low pressure steam or vapor heating boilers shall receive a certificate inspection biennially with an internal inspection every four years where construction will permit;

(3) Hot water heating and hot water supply boilers shall receive a certification inspection biennially with an internal inspection at the discretion of the inspector;

(4) Boilers and pressure vessels which are a part of a nuclear installation shall be inspected and reported in such form and with such appropriate information as the Department of Public Safety shall designate.


A grace period of two months beyond the periods specified in subdivisions (1), (2), and (3) of this section may elapse between certificate inspections. The chief inspector may, at his discretion, permit longer periods between certificate inspections.

34-29A-14. Boilers exempt from application of chapter.

This chapter does not apply to the following boilers:

(1) Boilers under federal control;

(2) Boilers located on farms if the farm is not regularly open to the general public and the boiler is used solely for agricultural or horticultural purposes;

(3) Heating boilers which are located in private residences or in apartment houses of less than six family units;

(4) Hot water supply boilers equipped with ASME-National Board approved safety relief valves which are directly fired with combustible fuel, electricity, or solar energy when none of the following limitations is exceeded:

(a) Heat input of two hundred thousand BTU per hour;

(b) Water temperature of two hundred ten degrees F;

(c) Nominal water capacity of one hundred twenty gallons;

(5) Boilers located in a refinery;

(6) Boilers used as part of an electrical generating plant;


(7) Historic power boilers as defined by § 34-29A-1. However, each boiler shall comply with rules promulgated under the provisions of § 34-29A-14.1.

34-29A-1. Definition of terms.

Terms as used in this chapter, unless the context otherwise requires, mean:

(1) "Boiler," a closed vessel in which water is heated, steam is generated, steam is superheated, or any combination thereof, under pressure or vacuum, for use externally to itself by the direct application of heat from the combustion of fuels, or from electricity, nuclear or solar energy. The term "boiler" includes fired units for heating or vaporizing liquids other than water where these units are separate from processing systems and are complete within themselves. The term "boiler" includes the apparatus by which heat is generated and all controls and safety devices associated with such apparatus or the closed vessel;

(2) "Certificate inspection," an inspection, the report of which is used by the chief inspector to decide whether or not a certificate as provided by § 34-29A-39 may be issued. This certificate inspection shall be an internal inspection when required; otherwise, it shall be as complete an inspection as possible;

(3) "Heating boiler," a steam or vapor boiler operating at pressures not exceeding fifteen psig,

(4) "High pressure, high temperature water boiler," a water boiler operating at pressures exceeding 160 psig or temperatures exceeding 250 degrees F;


(5) "Historic power boiler," a standard or nonstandard power boiler, including free-lance and scale models, owned by publicly operated museums, nonprofit organizations and individuals who preserve, maintain, exhibit, and only occasionally operate these boilers on a not-for-profit basis and for the primary purpose of perpetuating the agricultural and pioneer heritage of South Dakota;
34-29A-14.1. Rules and regulations for inspection of historic power boilers.

The Department of Public Safety shall promulgate rules, pursuant to chapter 1-26, to provide for the inspection of those historic power boilers otherwise exempt from the provisions of this chapter by § 34-29A-14. The rules shall provide for the inspection of such boilers and for a check of the boiler's safety devices. The rules shall also establish an inspection fee for a historic power boiler inspection. The rules may provide for reporting requirements, inspection reports, repair standards, notification of repair and other administrative procedures necessary to implement this section. The operation of a historic power boiler without complying with the rules promulgated pursuant to this section, by the owner, user or operator of the boiler is a Class 2 misdemeanor. Each day of operation in violation of this section is a separate offense.
 
When you have the plans, discuss with a club boiler inspector to gain advice on manufacture, and his confirmation that he will accept a boiler made to the plans for testing. Otherwise you may have a boiler he won't test or doesn't meet today's regulations. (Which is why I have converted 2 boilers recently to increase their strength to be able to be certified!).
I think most Martin Evans designs are still accepted in the UK. If you need calculations, I can do them for you, but would need to know the regulation limits relating to the certification as well. I have ASME and recently found a link to various States regs. I shall look-up regs for South Dakota...
I don't charge for doing the sums. - just message me personally if you need it.
K2
PS: A clause (Below) may mean you do not need a Test and certification: CHECK WITH the regulator: That's something I can't do for you. He may want a copy of the boiler plans. To have a letter from him saying "you don't need a certificate" is very valuable! - If you can get one.

34-29A-26. Inspections required for operating boilers--Frequency of inspection.

Each boiler used or proposed to be used within this state, except boilers exempt under § 34-29A-14, shall be thoroughly inspected as to their construction, installation and condition as follows:

(1) Power boilers and high pressure, high temperature water boilers shall receive a certificate inspection annually which shall be an internal inspection where construction permits, otherwise it shall be as complete an inspection as possible. Such boilers shall also be externally inspected annually while under pressure;

(2) Low pressure steam or vapor heating boilers shall receive a certificate inspection biennially with an internal inspection every four years where construction will permit;

(3) Hot water heating and hot water supply boilers shall receive a certification inspection biennially with an internal inspection at the discretion of the inspector;

(4) Boilers and pressure vessels which are a part of a nuclear installation shall be inspected and reported in such form and with such appropriate information as the Department of Public Safety shall designate.

A grace period of two months beyond the periods specified in subdivisions (1), (2), and (3) of this section may elapse between certificate inspections. The chief inspector may, at his discretion, permit longer periods between certificate inspections.

34-29A-14. Boilers exempt from application of chapter.

This chapter does not apply to the following boilers:

(1) Boilers under federal control;

(2) Boilers located on farms if the farm is not regularly open to the general public and the boiler is used solely for agricultural or horticultural purposes;

(3) Heating boilers which are located in private residences or in apartment houses of less than six family units;

(4) Hot water supply boilers equipped with ASME-National Board approved safety relief valves which are directly fired with combustible fuel, electricity, or solar energy when none of the following limitations is exceeded:

(a) Heat input of two hundred thousand BTU per hour;

(b) Water temperature of two hundred ten degrees F;

(c) Nominal water capacity of one hundred twenty gallons;

(5) Boilers located in a refinery;

(6) Boilers used as part of an electrical generating plant;


(7) Historic power boilers as defined by § 34-29A-1. However, each boiler shall comply with rules promulgated under the provisions of § 34-29A-14.1.

34-29A-1. Definition of terms.

Terms as used in this chapter, unless the context otherwise requires, mean:

(1) "Boiler," a closed vessel in which water is heated, steam is generated, steam is superheated, or any combination thereof, under pressure or vacuum, for use externally to itself by the direct application of heat from the combustion of fuels, or from electricity, nuclear or solar energy. The term "boiler" includes fired units for heating or vaporizing liquids other than water where these units are separate from processing systems and are complete within themselves. The term "boiler" includes the apparatus by which heat is generated and all controls and safety devices associated with such apparatus or the closed vessel;

(2) "Certificate inspection," an inspection, the report of which is used by the chief inspector to decide whether or not a certificate as provided by § 34-29A-39 may be issued. This certificate inspection shall be an internal inspection when required; otherwise, it shall be as complete an inspection as possible;

(3) "Heating boiler," a steam or vapor boiler operating at pressures not exceeding fifteen psig,

(4) "High pressure, high temperature water boiler," a water boiler operating at pressures exceeding 160 psig or temperatures exceeding 250 degrees F;


(5) "Historic power boiler," a standard or nonstandard power boiler, including free-lance and scale models, owned by publicly operated museums, nonprofit organizations and individuals who preserve, maintain, exhibit, and only occasionally operate these boilers on a not-for-profit basis and for the primary purpose of perpetuating the agricultural and pioneer heritage of South Dakota;
34-29A-14.1. Rules and regulations for inspection of historic power boilers.

The Department of Public Safety shall promulgate rules, pursuant to chapter 1-26, to provide for the inspection of those historic power boilers otherwise exempt from the provisions of this chapter by § 34-29A-14. The rules shall provide for the inspection of such boilers and for a check of the boiler's safety devices. The rules shall also establish an inspection fee for a historic power boiler inspection. The rules may provide for reporting requirements, inspection reports, repair standards, notification of repair and other administrative procedures necessary to implement this section. The operation of a historic power boiler without complying with the rules promulgated pursuant to this section, by the owner, user or operator of the boiler is a Class 2 misdemeanor. Each day of operation in violation of this section is a separate offense.
Hi Steamchick. Thanks for all this. The boiler for the 5a is rather large, compared to a Guage 1 loco. I won't be running this engine in public on a boiler. But I will build one eventually. Before doing the full up 5a boiler, I plan to do a small test boiler. Want to make sure correct practice is followed and it works. My "shop mentor" is the boiler inspector for our local 7.5" gauge club. Him and I have discussed the 5a boiler and the test boiler for about a year now and have worked out the assembly procedures. I own a real boiler test pump that goes to 850 PSI, so the boiler will definitely get tested correctly, both initial and annual. I also own a 7.5" gauge live steam 3 truck Shay locomotive. I had a chance to see the boiler's construction in progress and been thru several annual tests since then. Thanks again. Bob
 
So, one final wrap up. The Stuart 5a is a casting kit only. There is no bar stock or fasteners included. These are the leftover parts I did not use.



Leftovers.jpg




The big end brasses and spilt bearings are leftover due to a somewhat bad experience building a Stuart #4. These bronze castings are very soft and wear out quickly. After just a few hours running, the #4 needed a lower end rebuild. The eccentric parts are leftover because the Stevenson needs two of everything, plus all the linkage. I don’t understand why the eccentric appears to be for a Stevenson. Maybe it’s for a slip eccentric version. I have no idea what the piece om the lower middle is for. It’s not shown at all in the drawing. The flanges would have worked, just forgot they were on the shelf.



The 5a joins the Stuart family portrait



Stuart Family.jpg




The #8 was first in 1983, the #10V in 1989, #4 in 2020 and the 5a now.



If you want to order a Stuart product, I am not aware of any retailers in the USA. Order directly from Stuart in the UK on their website. They take all the major credit cards and will do the currency conversations. The prices on the website includes “Value Added Tax”, 16.5%, I think. The VAT only applies to customers in the UK and EU. Stuarts removes the VAT for customers in the USA. A nice savings, however shipping is expensive. Andrew at customer service is a good guy, Email him with questions and he’ll get back you.



Most Stuart products come directly from the Stuart warehouse packed in very nice boxes. The #5a and I would imagine other large engines come directly from the foundry in a relatively unmarked box. Stuart will send you a tracking number for shipment. Actively track the shipment progress. There is a high probability your shipment will get hung up by US Customs and they may not call you. You will have to call them and get the shipment moving again. My #5a got stuck in New York City. It took about a week of back and forth with a bureaucrat to get it out. My shop mentor had a shipment hung up in Memphis. Same thing, deal with a bureaucrat and the paperwork.



Bottomline: This was a fun project. Have a Stuart Victoria up next.



Take care, Bob
 
Nice to meet your Stuart family! A big round of applause from me! (You can possibly sell your spare castings on £&@y - to someone who needs them?).
(I guess I could but them, at prohibitive postage costs back to the UK. But I don't have a use... and someone else needs them.)
K2
 
Nice to meet your Stuart family! A big round of applause from me! (You can possibly sell your spare castings on £&@y - to someone who needs them?).
(I guess I could but them, at prohibitive postage costs back to the UK. But I don't have a use... and someone else needs them.)
K2
Hi K2. Thanks. I'll use those castings. Don't know for what yest.

vr Bob
 
Impressive line-up of Stuart engines! That pic really shows the size of the 5a compared to the 10-v.
 

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