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Rebuilding 30 HP Stanley bottom end.
Posted by: Howard Randall (IP Logged)
Date: February 13, 2003 01:12PM
<HTML>I am rebuilding the bottom end of a 30 HP Stanley engine - new crank shaft, renewed main bearing surfaces, and new bearings. Planning, in addition to the (3/8) locating key, a heavy shrink fit for all elements on shaft - gear, valve eccentrics, crank throws- to resist torque. Anyone have any experience on how heavy a fit this was on original engines? (The reason for rebuilding is that, along with noisy main bearings, the crank throws were loose on the shaft.) Are there any other design alternatives working out there to resist the considerable torque of these beasts?</HTML>
Re: Rebuilding 30 HP Stanley bottom end.
Posted by: George Nutz (IP Logged)
Date: February 13, 2003 02:51PM
<HTML>Howard,
The press fit should be a FN4 at least but that depends on the material and cross sections involved. The force required for a press fit is F=pi f p d l , p =15,000psi stress for a .0014"/one inch diameter press, f is coefficient of friction, can use .2 .
d=diameter and l=length. F is in pounds, pi is 3.14. To find the torque capability multiply that by d/2 and that answere is in inch-pounds. A thirty horsepower Stanley can produce almost 3,000 foot-pounds of stall torque with 600psi on the steam chest! Usually very high press fits are done with steels of yield strength of 80,000psi or more for a good margine of safety. You will probably need a 20 ton press or more.
George</HTML>
The press fit should be a FN4 at least but that depends on the material and cross sections involved. The force required for a press fit is F=pi f p d l , p =15,000psi stress for a .0014"/one inch diameter press, f is coefficient of friction, can use .2 .
d=diameter and l=length. F is in pounds, pi is 3.14. To find the torque capability multiply that by d/2 and that answere is in inch-pounds. A thirty horsepower Stanley can produce almost 3,000 foot-pounds of stall torque with 600psi on the steam chest! Usually very high press fits are done with steels of yield strength of 80,000psi or more for a good margine of safety. You will probably need a 20 ton press or more.
George</HTML>
Re: Rebuilding 30 HP Stanley bottom end.
Posted by: Pat Farrell (IP Logged)
Date: February 14, 2003 05:13AM
<HTML>Which model is your 30 H.P. Stanley going into? On my Stanley 30 H.P. crank shaft that I recently rebuilt with a larger drive gear, I found to get moving results, that with my 32 ton press even needed heat from a torch added. It went back on just as tight. According to Art Hart, I was lucky to have not scored the shaft during the pressing, as most of the 30 H.P. crank throws he has removed have scored the shaft and bores on removal. The 20 H.P. crank throws easily press on and off with my 32 ton press without using any heat. I would guess their press takes about 25 tons for movement. A 10 H.P. crank shaft takes normally as low as 10 tons to as high as 14 tons. As insurange against the crank throws from accidentally backing off the shaft in use, I drill and tap for an allen head 1/4" x 1/4" N.C. set screw into the interference of the shaft and throw. I have heard this is called a Dutchman. Center punch around the outside of the set screws to prevent them from accidentally backing out.</HTML>
Re: Rebuilding 30 HP Stanley bottom end.
Posted by: George Nutz (IP Logged)
Date: February 14, 2003 05:53PM
<HTML>Pat,
Thanks for the practical experience and information. Press fits must be totally in line,any skewing upon start and the whole interference fit can be badly damaged and extruded. I would caution about using a "dutchman" as it adds a major stress concentration point and could relieve the press fit pressure significantly. Your press fit forces remind me of the old SAAB three cylinder 2 cycle crankshaft that was pressed together, one of the engineers at MIT loved rebuilding these small cranks and mentioned he needed a 60 ton press to accomplish the press fits! Guess the swedish aircraft builder SVENSKA used really high quality steels in this little engine to allow such high press fits.</HTML>
Thanks for the practical experience and information. Press fits must be totally in line,any skewing upon start and the whole interference fit can be badly damaged and extruded. I would caution about using a "dutchman" as it adds a major stress concentration point and could relieve the press fit pressure significantly. Your press fit forces remind me of the old SAAB three cylinder 2 cycle crankshaft that was pressed together, one of the engineers at MIT loved rebuilding these small cranks and mentioned he needed a 60 ton press to accomplish the press fits! Guess the swedish aircraft builder SVENSKA used really high quality steels in this little engine to allow such high press fits.</HTML>
Re: Rebuilding 30 HP Stanley bottom end.
Posted by: David K Nergaard (IP Logged)
Date: February 15, 2003 02:05PM
<HTML>While you have the thing apart, why not consider fitting new cranks using modern bearings? Look at the SKF series 222.</HTML>
Re: Rebuilding 30 HP Stanley bottom end.
Posted by: Howard Randall (IP Logged)
Date: February 21, 2003 12:17PM
<HTML>Thanks George, Pat and David!
David, Have you any experience with these SKF bearings?</HTML>
David, Have you any experience with these SKF bearings?</HTML>
Re: Rebuilding 30 HP Stanley bottom end.
Posted by: George Nutz (IP Logged)
Date: February 21, 2003 01:19PM
<HTML>Howard,
The very strong Bryan piston valveengine used off the shelf insertable SKF bearings for that 4"X5" engine, much easier than grinding raceways. Seems like a very good way to go.</HTML>
The very strong Bryan piston valveengine used off the shelf insertable SKF bearings for that 4"X5" engine, much easier than grinding raceways. Seems like a very good way to go.</HTML>
Re: Rebuilding 30 HP Stanley bottom end.
Posted by: David K Nergaard (IP Logged)
Date: February 22, 2003 11:08AM
<HTML>Howard, no experience yet, but the new rods I am making for my 20 hp. will use them. I will keep you informed.</HTML>
Re: Rebuilding 30 HP Stanley bottom end.
Posted by: Pat Farrell (IP Logged)
Date: February 23, 2003 01:20AM
<HTML>I have had years of experience with SKF bearings in both our 10, 20, and 30 H.P. engines. My 10 H.P. has about 20,000 miles on it's SKF bearings. My 20 H.P. has only 1,200 miles on it's new bearings. My 30 H.P. doesn't have any miles on it yet with it's model 85 body. Use self aligning SKF in the connecting rods and straight SKF roller bearings in the main bearings. You only have to put them in once and they are good for life. Email me direct for any additional information that you need. SSsssteamer</HTML>
Re: Rebuilding 30 HP Stanley bottom end.
Posted by: Howard Randall (IP Logged)
Date: February 24, 2003 12:37AM
<HTML>Pat, what is your e-mail address?</HTML>
Re: Rebuilding 30 HP Stanley bottom end.
Posted by: Pat Farrell (IP Logged)
Date: February 24, 2003 12:48PM
<HTML>rp.farrell@verizon.net</HTML>
Re: Rebuilding 30 HP Stanley bottom end.
Posted by: David K Nergaard (IP Logged)
Date: February 26, 2003 07:45PM
<HTML>Considering how flexible the Stanley engine frame is, I would strongly suggest self aligning bearings for both mains and rods.</HTML>
Re: Stanley # 8 engine bearings
Posted by: C Benson (IP Logged)
Date: February 28, 2003 01:16PM
<HTML>Dissagree,,,,ball in the mains,,///BARRELL in the rods,,,Dont make the E.Gillant error of cutting the main caps too thin,,thats just not necessary,,Cheers Ben</HTML>
Re: Stanley # 8 engine bearings
Posted by: David K Nergaard (IP Logged)
Date: March 02, 2003 11:34AM
<HTML>Ben, I must disagree. Putting severe bending/cross loads on a ball bearing is not the correct way to keep the frame from twisting!</HTML>
Re: Stanley # 8 engine bearings
Posted by: C Benson (IP Logged)
Date: March 02, 2003 03:57PM
<HTML>The whole thing is contrary to good practace,,,,including the skip jump roller tracks,,,,,I doubt the races stay round either,,,Rollers are the MOST critical to have in alignment,,,to tenths,,,,the balls are less fussy,If water an dirt are kept out,,I think the ball will stand a chance,,,and I think your stiffining plates should be mandatory,,,, Weather,snow,ice rain YUC,,,,Think spring,,,Ben</HTML>
Re: Stanley # 8 engine bearings
Posted by: David K Nergaard (IP Logged)
Date: March 06, 2003 05:27PM
<HTML>The roller bearings I am suggesting are spherical race self aligning with barrel shaped rollers.</HTML>
Re: Stanley # 8 engine bearings
Posted by: C Benson (IP Logged)
Date: March 06, 2003 07:50PM
<HTML>And what is the price now,,,,The balls still are better than the original I think,,,,,Cheers Ben</HTML>
Re: Stanley # 8 engine bearings
Posted by: George Nutz (IP Logged)
Date: March 06, 2003 08:14PM
<HTML>I would agree with "BEN" on the roller bearings on the crankshaft mains and with Dave on the connecting rod using self aligning double spherical roller bearings on the connecting rods, they have a tremendous load capacity In there narrow size can be the same width as single ball bearings with much greater load capacity. This is as long as helical gears are not in use like the SV. Good luck with the project Howard!
George</HTML>
George</HTML>
Re: Stanley # 8 engine bearings
Posted by: Howard Randall (IP Logged)
Date: March 07, 2003 11:06AM
<HTML>With the right cross-head design, isolating as much axial load to the connecting rod-ends with self aligning double spherical roller bearings might allow ball bearings on the main. Pat's experience with 10 and 20HP's is encouraging.
Right now I am back to the drawing board (or better stated, trying to dusting off my CADD skills as I have misplaced my triangles, T-square, and compass). GOOD LUCK is very appropriate George.
The hope was to keep things as original as possible. Too much original stuff is disappearing with little or no documentation. The original bearing surfaces have been cleaned up and I will do a new layout based on the new dimensions. I can then look at the alternatives all of you have been so kind to offer. THANKS
Piston rods are also under scrutiny. These have been "messed with", so will take some thought. All needs to be done and the bits put back together in time for the touring season this summer!
While more costly, the best may be to put the old stuff in a box and reproduce critical elements using modern materials and technologies.
George, are you available for some layout work if I get stuck? I taught Mechanical Drawing at a local college years ago. Taught myself Generic CADD 10 years ago and took an AutoCAD course 5 years ago, but have not used either recently.
Thanks for all the input. Will keep you posted.</HTML>
Right now I am back to the drawing board (or better stated, trying to dusting off my CADD skills as I have misplaced my triangles, T-square, and compass). GOOD LUCK is very appropriate George.
The hope was to keep things as original as possible. Too much original stuff is disappearing with little or no documentation. The original bearing surfaces have been cleaned up and I will do a new layout based on the new dimensions. I can then look at the alternatives all of you have been so kind to offer. THANKS
Piston rods are also under scrutiny. These have been "messed with", so will take some thought. All needs to be done and the bits put back together in time for the touring season this summer!
While more costly, the best may be to put the old stuff in a box and reproduce critical elements using modern materials and technologies.
George, are you available for some layout work if I get stuck? I taught Mechanical Drawing at a local college years ago. Taught myself Generic CADD 10 years ago and took an AutoCAD course 5 years ago, but have not used either recently.
Thanks for all the input. Will keep you posted.</HTML>
Re: Stanley # 8 engine bearings
Posted by: C Benson (IP Logged)
Date: March 07, 2003 12:36PM
<HTML>Time for more naarth/wood humor,,rr,,rr,,,[was --5 last nite] ,,,Howard,,So glad to hear you are of a mind to be respectful of originality,,,,I WAS really worried you had found a retrofit I hadent thot ov for the eccentric strap [ball] bearin's,,,,,,haha Ben,,,,,P/S dont forget taki'n off the pistons WILL distroy the threads//,,at least all their good properties,,,,a few eng have been destroyed from this error,,cb</HTML>
Re: Stanley # 8 engine bearings
Posted by: David K Nergaard (IP Logged)
Date: March 07, 2003 12:47PM
<HTML>Taking the pistons off a Stanley rod can destroy the threads in the piston. Those on the rod will be undamaged except where the factory peened the end, which is why the piston threads get reamed. You can clean up the rod threads with a thread file. If you clean up the threads after unscrewing one half of the piston, you can unscrew the other without damage. Then either use a new half piston or bush the old one.</HTML>
Re: Stanley # 8 engine bearings
Posted by: Howard Randall (IP Logged)
Date: March 07, 2003 02:01PM
<HTML>Ben and David, thanks for the heads-up.
I learned the hard way from someone else’s (un) screw-up / faulty refitting of the piston after removal. With about a mile to go on the last day of the tour in Canada a few years back, I was driving Norm Miller’s 20 HP (13 or 14) touring when a piston let go. Fortunately, I herd it slapping back and forth on the rod and stopped the car just before it lit go. As we pushed the car on to the trailer the piston finally came off the rod and jammed, but no serious harm done. A close one!
With all the use these cars are seeing, original engine rebuilding is inevitable. Perhaps it time for a Stanley Engine rebuild “DO’S and Don’ts” list. Perhaps we can begin to standardize on some fixes. The 10HP is particularly vulnerable and spare engines are like hen’s teeth compared to 20HP's. The one piece connecting rods don’t help when rebuilding. Howard Johnson has produced a run of 10 HP bottom end rebuild kits with new 2 piece rods, modern rod and main bearings, and throws. These should get a shakeout this season in several cars.</HTML>
I learned the hard way from someone else’s (un) screw-up / faulty refitting of the piston after removal. With about a mile to go on the last day of the tour in Canada a few years back, I was driving Norm Miller’s 20 HP (13 or 14) touring when a piston let go. Fortunately, I herd it slapping back and forth on the rod and stopped the car just before it lit go. As we pushed the car on to the trailer the piston finally came off the rod and jammed, but no serious harm done. A close one!
With all the use these cars are seeing, original engine rebuilding is inevitable. Perhaps it time for a Stanley Engine rebuild “DO’S and Don’ts” list. Perhaps we can begin to standardize on some fixes. The 10HP is particularly vulnerable and spare engines are like hen’s teeth compared to 20HP's. The one piece connecting rods don’t help when rebuilding. Howard Johnson has produced a run of 10 HP bottom end rebuild kits with new 2 piece rods, modern rod and main bearings, and throws. These should get a shakeout this season in several cars.</HTML>
Re: Rebuilding 30 HP Stanley bottom end.
Posted by: allen blazick (IP Logged)
Date: March 08, 2003 10:03PM
<HTML>Howard, have you owned this engine for a long time? Allen</HTML>
Re: Rebuilding 30 HP Stanley bottom end.
Posted by: Mike Clark (IP Logged)
Date: March 08, 2003 10:17PM
<HTML>Howard - try Turbocad - much cheaper than Autocad and perfect for what you intend to do - not hard to learn either.
Mike</HTML>
Mike</HTML>
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