Friction Steam Boiler

[rickoff]

Latest correspondence with Lloyd Tanner

Hi folks,

This post includes my latest correspondence to, and reply from, Lloyd Tanner. Please note that, in his reply, Lloyd is giving details concerning his newer friction roller design, which can feed several pieces of wood simultaneously. With the new design, Lloyd has increased the operating temperature and pressure to 700 degrees @ 300 psi. The new design features a horizontal roller that is 10 inches in diameter, and 36 inches long (full width of trough). It is interesting to note that the amount of water contained in each "drop" is said to be 1/2 teaspoon, which is roughly 2.5 milliliters. As pointed out in my correspondence to Lloyd, a normal droplet of water is about .025 milliliters, and would be just 1/100 of Lloyd's controlled water drop amount. Thus, his water drop is actually a metered amount rather than a natural drip. From Lloyd's description, it would appear that these metered amounts are dropped at 4 inch intervals along the length of the water distribution rail in a linearly progressive manner, from one end of the rail to the other.

My correspondence to Lloyd:
Sent: Sat 12/06/08 4:50 AM
Hi Lloyd,

Thought you might be interested to know that we are currently at over 9,000 views by people interested in your friction heater, and many are interested in building replications. I think that I have been able to answer most questions to the satisfaction of inquirers, but lately the topic of discussion has focused on steam production as related to your original vertical rotor design. Specifically, people are asking about the volume of steam per minute that is created over a period of time that would determine an average output volume of sustainability. This knowledge, of course, would enable us to determine what size steam engine might be realistically feasible. For example, let's consider the 10 horsepower Green Steam Engine. It has two cylinders, each with a 3.125 inch bore and a 1.125 inch stroke. The displacement of each cylinder is equal to Pi times 2.4414 (the cylinder radius squared) times 1.125, or 8.632ci (cubic inches). Thus the total displacement per revolution is 2 times 8.632, or 17.264. Converted to liters, that would equal 0.28 liter per revolution. Theoretically, then, a 5 hp engine's displacement would be half that amount (0.14 liter), and that of a 2 hp engine would be 0.056 liter. If you require 1 hp to drive the rotor shaft, you would appear to have 1 reserve horsepower left over to perform other work (such as driving an electric generator) if you are using a 2 hp steam engine. You have said that the rotor shaft speed needs to be about 1800 rpm. At 1800 rpm, we would require a volume of steam equal to 1800 x 0.056, or about 100 lpm (liters per minute) to operate a 2 hp steam engine. One drop of distilled water is equal to about .025ml volume. Exploded to steam, at a factor of 1600 to 1, that drop has a volume of 40ml. Thus, it would require 25 exploded drops to equal roughly 1 liter of volume, or 2500 drops per minute to produce 100 lpm of steam, and that equates to about 42 drops per second. Of course the steam would also have to remain at a fairly constant and adequate pressure for a sustained period of time. Operating a 2 hp Green Steam Engine at 1800 rpm would require a pressure of about 50 psi.

I know that you have done some testing at various steam pressures and temperatures. Do you have any test data that you could share with us? Absent any actual output volume measurements, I can compute the steam production volume if I know 4 factors:
1. The sustained psi pressure of the steam.
2. The sustained temperature of the steam.
3. The time period of the sustained test (should be perhaps 10 minutes or more).
4. The amount of water that is fully converted to steam during the test period. I would actually suggest timing the period required to fully convert 1 kilogram of water (1 liter) to steam at a sustained temperature and 50 psi pressure.

Any such data that you can supply will be greatly appreciated, as has all the information that you have so generously shared with us.

Best wishes to you during this Holiday season, and always,

Rick




------------------------------------------------------------------

Lloyd's reply:
From: LKTanner Sent:Fri 12/12/08 5:44 PM

Hi Rick - Thank you for your email of last Saturday, December 6, 2008. Please forgive me for the delay in getting back to you. I may have told you before that I don't know how to use a computer so I have to have my wife do all of my replies and she has been busy with therapy with her new knee. I really appreciate your interest in this project and want to thank you again for all of your input, time and comments.

In answer to your questions - I am not very educated and therefore I answer these to what I know from my own testing. If you have a 10" diameter roller turning at 1700 r.p.m. or more, I have gotten the floor of the pressure vessel to 700 degrees with 10 lbs. of friction pressure against the friction roller.

I have reached 300 lbs. of pressure in my pressure vessel and have sustained 300 lbs. of pressure by letting the water in and carefully regulating the 1/2 teaspoonful drop of water falling to the floor of the pressure vessel. NOTE: My roller is 3' long and my drops start at one end and drip 4" apart the length of the roller. By the time the drops start at the far end again, the floor of the pressure vessel's first 4'' is back from 500 degrees to 700 degrees - you lose 200 degrees when the drop hits the first 4". The steam in the pressure vessel rises up into the pressure dome and that's where you discharge your steam to run whatever you want to run. If you want more heat, you increase the friction pressure against the friction roller. My water reservoir holds 20 gallons and never runs empty. It feeds my pressure vessel. My water hopper holds 5 gallons and takes about 1/2 hour to empty. It refills in less than 5 minutes.

Note that your water bar [water distribution rail] should be 1" above the floor of the pressure vessel.

We saw an article on CNN the other night about an engineer named Peter Jansson at Rowan University (Glassboro, NJ) who is working with a
gentleman's formula where he adds salt water to a chemical to use as fuel. We continue to be in touch with Rowan and they are very excited about my concept as well.

Best wishes for the holidays to you and your family!

Lloyd L. Tanner

[Alana]

@ Rick

Thank you so much for you correspondence and also for effort to get more detailed information about Lloyds device.
I think I haven't understood everythink Lloyd want to explain to us.

1. I think the diameter of the friction rotor increased in size: from 5 " to 10 ".
2. Lloyd explained that he drops in 1/2 teaspoonfull water drops. But in which time? I think this amount (1/2 teaspoonfull water) refers to the amount of water per second.
3. Lloyd has written: "My roller is 3' long and my drops start at one end and drip 4" apart the length of the roller." I don't know which part of his device he mean. I think he described the length of the water pipes which drops in the water in the steam vessel. I also think that the drops fall from a high of 4 ".

I hope Rick or someone else can understand Lloyds explanations better then I did. I am also very surpriced by the small amount of water Lloyd uses for his device (1/2 teaspoonful of water drops maybe per secound would be a sensation!!!)

Best wishes
Alana

[nonubbins]

EDIT: While I was posting this, Rick added some info from Lloyd.
Lloyd said.....

My water hopper holds 5 gallons and takes about 1/2 hour to empty. It refills in less than 5 minutes.

Wow, thats about 125K btu/hr. With a 10"Dx36"L roller, is he using electric or steam engine, and how many horsepower? At 1700 rpm, he doubled his surface speed which means we'll need a bigger motor/engine.
Thank you Rick!

I was thinking about an I - beam as the trough for the wood seems that it might be a good base for the wood to slide on toward the wheel... cut a hole in the middle of one and you would have most of the base made.

Please keep us posted on your progress...

Thanks

Good idea. It would be solid!

I've been playing around with a setup to test some ideas. I looked for a piece of equipment to set up Randy's idea without a lot of hassle. I didn't have anything so I cheated and chucked an oak block in my wood lathe. I turned a ring onto the face of the block with a 5.5in OD and 3in ID. This gives about 16 sq in to equal a 4x4 and the center line of the ring equals about 467 ips at 2100 rpm. I used a 1 gal paint can turned on its side, drilled a hole in the upper side to fill it with water and pushed the top of the can against the ring of wood(the bottom has reinforcement ridges). Some heat at first but disappointing. And once the wood charred the heat output went down!!! Turned the wood clean and it would work until it charred again!!! Wondering what the texture of the metal plays in this, I sanded the top of the can with 120 emery cloth which made big difference! Used 100 grit and now I get small puffs of smoke and even more heat. I got the upper side of the can to 200F. It seems that we need enough "bite" to help shed the carbon but not so much that it wastes wood. I will insulate the can and stir the water to eliminate stratification in the next few days. This should give us an idea of btu output. And only $3 out of pocket so far.

Thanks,
Dan

[rickoff]

Crunching the numbers

@ Rick

Thank you so much for you correspondence and also for effort to get more detailed information about Lloyds device.
I think I haven't understood everythink Lloyd want to explain to us.

1. I think the diameter of the friction rotor increased in size: from 5 " to 10 ".
2. Lloyd explained that he drops in 1/2 teaspoonfull water drops. But in which time? I think this amount (1/2 teaspoonfull water) refers to the amount of water per second.
3. Lloyd has written: "My roller is 3' long and my drops start at one end and drip 4" apart the length of the roller." I don't know which part of his device he mean. I think he described the length of the water pipes which drops in the water in the steam vessel. I also think that the drops fall from a high of 4 ".

I hope Rick or someone else can understand Lloyds explanations better then I did. I am also very surpriced by the small amount of water Lloyd uses for his device (1/2 teaspoonful of water drops maybe per secound would be a sensation!!!)

Best wishes
Alana

Hi Alana,

I have numbered my responses according to your questions:

1. I think that a better understanding becomes apparent if you study Lloyd's hand drawn diagrams of post #41, and especially the second, larger drawing, showing the side view. This is the design that Lloyd is referring to in his correspondence. I'll show that diagram here once more to make my explanations easier to follow.

The old design uses a 5" diameter rotor hub mounted on a vertical shaft, whereas the newer horizontal shaft roller design uses a 10" diameter roller which is 36" long. This would allow up to 9 pieces of 4"x4" wood to be pressed against the roller surface on each side of the trough. I think that Lloyd originally planned to use a 5" diameter roller, but then settled on the 10" diameter because it would afford much greater stability. The larger diameter also retains and provides heat for a longer time period whenever the friction process is halted. Then too, the larger diameter requires less curvature of the wood ends to make full contact with the roller, so increases efficiency of curvature wear-in.

2. Each water drop point along the water distribution rail is dropping 1/2 teaspoon (2.46ml) of water to the floor of the steam vessel separately in a timed sequence. To determine the actual amount of water dropped per second, we must refer to the information Lloyd gives us. He stated that he maintains temperature and pressure by carefully regulating the water inflow rate. During 1/2 hour of operation, 5 gallons (18.93 liters) of water is converted to high pressure, high temperature steam. Since there are 9 water drop points along the water distribution rail, and each metered water drop is 1/2 teaspoon (2.46 ml) in volume, each water drop point is releasing 1/9 of the 5 gallon total during the 30 minute test, or 0.5556 gallon (2.10 liters). That equates to 0.0185 gallon (70ml) per minute, or 0.00031 gallon (1.667ml) per second at each drop point. To achieve a full 1/2 ounce (2.46ml) water drop, therefore, requires about 1.5 seconds of time for each water drop point along the distribution rail. The next 1/2 teaspoon drop for that point would occur during the next 1.5 second time period. Since there are 9 water drop points, 9 water drops will occur during the 1.5 second time cycle, so the total water dispersed is 22ml during each 1.5 second cycle, which is equivalent to a total average dispersal rate of 15ml per second, or 900ml per minute. As for the steam production, since the temperature of the drop chambers varies between 500F and 700F degrees, let's use 600F degrees as the mean average temperature factor, and use 300 psi (Lloyd's test data) as the sustained pressure. At this temperature and pressure, the specific volume of superheated steam is equal to 0.118942 cubic meters per kilogram of water converted. One kilogram of water is equal to 1 liter, and 900ml is 0.9 liter. Therefore, 0.9 times 0.118942 gives us the steam volume production per minute, which is 0.1070478 cubic meters per minute, and which equals 107.05 liters per minute. Now keep in mind that this represents the max (or near maximum) sustainable output rate during a 30 minute test. We don't require 300 psi operation pressure to run a steam engine, as 50 psi sustained pressure will do very nicely, and we can deliver 0.60312 cubic meters steam per kilogram of water at that pressure. That equates to 542.81 lpm (liters per minute) of steam. Is that enough steam to drive a suitable steam engine? Well, Lloyd's newer roller design, with multiple wood pieces, should run just fine with a 10 hp Green Steam Engine (just for example), which can easily run at the desired 1800 rpm level on 50 psi steam pressure. It displaces 0.28 liters per revolution, so would require 1800 times that amount, or 504 lpm. Thus, we would be operating with a 38.81 liters per minute reserve capacity, and it does seem possible that this could be a self-runner. The older, original 5" vertical rotor, design will require a 1 hp drive source, and therfore roughly 1/10 the volume of steam produced by the horizontal roller design when operating at the same rpm level.

3. From the diagram above, you can see that each drop point along the distribution rail is positioned above a separated drop chamber at the floor of the vessel. The diagram shows 11 drop points, but keep in mind that it was just a concept drawing when originally produced. Lloyd decided upon actually having 9 equally spaced drop points along the distribution rail. The first drop point is placed 2" from the end of the rail, and the remaining eight drop points are spaced exactly at 4" intervals. This places the drop points above the center of each of the nine 4" chambers at the vessel floor. The distribution rail is positioned within the steam vessel so that the underside of the rail (where the water is released) is 1" above the floor of each chamber. It appears to be higher than that in Lloyd's drawing, but again remember that the drawing is meant only to show the overall concept view, and that Lloyd's final design incorporates measurements which can and do differ somewhat. From Lloyd's description, it becomes apparent to me that he is regulating the water drop points to disperse water in 1/2 teaspoon increments, and in progressive order from one end of the distribution rail to the other. The diagram above shows multiple droplets falling more or less simultaneously, so forget about that for a moment, as that would be incorrect. Instead, imagine that the first water drop point at the left end of the distribution rail has just dropped 1/2 teaspoon of water at the center of the first (leftmost) chamber at the vessel floor. Prior to the water contacting the chamber floor, the floor is at 700F degrees. As the water hits the floor of that chamber, the heat transer to the water is nearly instantaneous. The chamber floor gives up 200 degrees of heat in the steam conversion process, dropping the temperature of the chamber floor to 500F degrees. It does take a certain amount of time for the floor temperature of that chamber to return to 700F degrees, and this recovery period is allowed for by spacing out the water drop interval so that it only occurs after the remaining eight drop points along the distribution rail have discharged their water to their corresponding chambers. Thus, as Lloyd says, by the time the water drop starts at the far (right) end of the distribution rail, the first chamber at the left end has returned from 500F degrees to 700F degrees, and is ready to receive the next 1/2 teaspoon water discharge. While Lloyd seems to be describing a linear distribution sequence from left to right, this may not actually be the case, and may not be the most advantageous distribution order. I would tend to think that whenever there is a temerature drop in one chamber, the directly adjacent chamber will also be affected, although to a far lesser degree. Still, it may be more advantageous to time the water drops to occur at wider intervals along the distribution rail. For example, instead of occurring in a |1|2|3|4|5|6|7|8|9| sequence, it might be preferred to change the sequence order to |1|4|7|2|5|8|3|6|9|. This would help to ensure that adjacent chambers are fully recovered before water is discharged into them.

I hope these explanations serve to answer any questions that may have remained, previous to learning Lloyd's results, and that it suitably clarifies what Lloyd has stated. I believe that my numbers are correct as stated, an will let them rest for now. If anyone finds them to be in error, please let me know and I will correct them. For now, though, I need to need to take a couple of painkillers and relaz - just had a tooth extraction yesterday, and the pain is really kicking in something wicked now.

Best regards to all,

Rick

[nonubbins]

Rick
Ouch, I hope you feel better soon! If you haven't, read my edit in #183. I'm curious!
Thanks
Dan

[Vortex]

crunching the numbers

Hey Rick,

If anyone finds them to be in error, please let me know and I will correct them. For now, though, I need to need to take a couple of painkillers and relaz - just had a tooth extraction yesterday, and the pain is really kicking in something wicked now.

An Extraction can be a Distraction... Get feeling better soon.

The numbers for steam creation look good.
Thank you very much for all the effort you are putting into this.

For example, let's consider the 10 horsepower Green Steam Engine. It has two cylinders, each with a 3.125 inch bore and a 1.125 inch stroke. The displacement of each cylinder is equal to Pi times 2.4414 (the cylinder radius squared) times 1.125, or 8.632ci (cubic inches). Thus the total displacement per revolution is 2 times 8.632, or 16.724ci.

CORRECTION: 2 x 8.632 = 17.264 cu inches.
When I had crunched my numbers awhile back, I rounded and was using 8.62 cu inch per cylinder.
Since your cylinder cu inch and mine differ a tad the end results between yours and mine will be a bit off.

1000 rpm consumes 17250 cubic inches
1600 rpm consumes 27600 cubic inches
1800 rpm consumes 31050 cubic inches
1 liter = 61.02 cu inches
1800 rpm = 508.8 liters per min steam
508.8 liter = 134.4 gallons / ~1600 = 0.084 gallon per min = 5.04 gallons water per hour
The above numbers had me concerned after I had crunched them,
as far as the smaller friction device goes.


Maybe I missed it, is Lloyd still using the original 1HP motor to turn the
newer larger rotor/roller or is it a larger motor?

The rpm is a guess I'm sure. Could you ask Lloyd what the diameter
of each pulley wheel is, on the motor and roller and the rated rpm of the motor. OR has Lloyd direct connected the motor to the rotor/roller?

When might we expect some pictures of the new device, hopefully inside and out?
In the new/larger device, is the wood still being weighted down?

Very good.
Randy

[rickoff]

Reply to Randy (Vortex):

Hey Rick,

An Extraction can be a Distraction... Get feeling better soon.

The numbers for steam creation look good.
Thank you very much for all the effort you are putting into this.


CORRECTION: 2 x 8.632 = 17.264 cu inches.
When I had crunched my numbers awhile back, I rounded and was using 8.62 cu inch per cylinder.
Since your cylinder cu inch and mine differ a tad the end results between yours and mine will be a bit off.

1000 rpm consumes 17250 cubic inches [17,264ci]
1600 rpm consumes 27600 cubic inches [27,622ci]
1800 rpm consumes 31050 cubic inches [31,075ci]
1 liter = 61.02 cu inches
1800 rpm = 508.8 liters per min steam [504 lpm]
508.8 liter = 134.4 gallons / ~1600 = 0.084 gallon per min = 5.04 gallons water per hour
[504 liters = 0.504 cubic meter]
[steam density = 1.65805 kg/cubic meter = 0.836 kg]
[0.836 x 60 minutes = 50.16 kg per hour]

The above numbers had me concerned after I had crunched them,
as far as the smaller friction device goes. [Why is that?]


Maybe I missed it, is Lloyd still using the original 1HP motor to turn the
newer larger rotor/roller or is it a larger motor?

The rpm is a guess I'm sure. Could you ask Lloyd what the diameter
of each pulley wheel is, on the motor and roller and the rated rpm of the motor. OR has Lloyd direct connected the motor to the rotor/roller?

When might we expect some pictures of the new device, hopefully inside and out?
In the new/larger device, is the wood still being weighted down?

Very good.
Randy

Thanks, Randy, the displacement correction provides an additional 1/100 liter of total diisplacement per revolution, bringing that figure to 0.28 liter. At 1800 rpm that means we require 504 lpm steam to operate the 10 hp engine. A 1 hp engine, suitable to drive the vertical shaft design, would require about 1/10 the steam volume of the 10 hp model, or about 50.4 lpm.

The 1 hp induction motor used by Lloyd in his demos was used in a 1:1 drive ratio to rotate the rotor shaft. The motor is rated at 1800 rpm synchronous speed, and would run at about 1745 rpm under full load.

Lloyd has definite plans to drive the horizontal roller model with direct (PTO) drive from a steam engine, and expressed interest some time ago in building the 10 hp Green Steam Engine. It would seem to be well suited to the application. If it turns out that it can't quite handle driving the roller shaft to at least 1700 rpm on 50 psi steam pressure while working a full wood load, the pressure can be increased. If the increase in pressure uses more than the 38.81 lpm reserve capacity, we would not have a self-runner, but it appears evident that the amount of additional auxiliary drive power required, beyond that supplied by the steam engine, would be a very small amount.

Yes, the wood pieces are all weighted with 10 lbs force, and Lloyd is certainly using a larger drive motor for the new unit. If it required 1 hp to drive the older unit with two pieces of wood used, I think we can safely assume it may require about 9 hp to drive the new design, which will hold up to 18 pieces of wood 4"x4" pieces.


Best regards,

Rick

[rickoff]

Rick
Ouch, I hope you feel better soon! If you haven't, read my edit in #183. I'm curious!
Thanks
Dan

I did read that Dan, and it looks like I have already answered the questions. Yes, with the 10" roller, Lloyd has effectively doubled the surface speed of the friction rotor, which produces even more heat. It has the same effect as running a 5" roller at 3600 rpm.

In reply to your question of post # 177,

Rick, are you saying that we are capturing the exhaust to reuse ie a closed system or simply running the steam through a heat exchanger and vented to atmoshere?

You had asked if a self-runner was possible, and I had replied that I thought so, and gave reasons why. In speaking of recapture of steam to heat input water, I'm sure you would agree that any pre-heating of input water would make the steam generation process more efficient. The simplest way to recapture heat would be, as you say, a heat exchanger which passes through either the water hopper, or the water reservoir, and which is finally vented to atmosphere (perhaps being allowed to condense within a vented tank). We certainly don't want to recapture steam heat by any method that would cause back pressure to mount. The engine exhaust must move freely.

Keep in mind too, that Lloyd's setup has a steam line running from the steam vessel box directly to the water reservoir. The purpose of this line is to equalize pressure, but it also introduces heat which helps raise the water temperature in the reservoir. Every degree of pre-heating that we can capture is going to be of benefit, and brings the theoretical idea of a self-runner closer to reality. I don't imagine that anyone is going to want a self-runner just for the sake of having one. To perform useful work, you would have to sacrifice self-runner capability in order to use that energy potential for real benefit.

Best regards,

Rick

[rickoff]

An interesting link....

I noticed this link, posted by Vortex (thanks, Randy!) in the Self-Running Ambient Heat Engine thread, and checked it out. It concerns the use of steam mixtures of water and benzene, which dramatically improve steam engine efficiency. Definitely worth a read, and I see no reason why the theory could not be utilized with Lloyd's device. Read the basics here:
Bernhard Schaeffer: Benzene-Steam Engine

Though most of the technical writings are only in German, there are two English pdf documents that are quite interesting. The first tells the story of Bernhard Schaffer's lifelong quest to disprove the Second Law of Thermodynamics, and of his success at doing so. Find that here:
http://www.lesa-maschinen.de/cms/upl...A-Story_en.pdf

The second English document deals with the mathematical equations relevant to water/benzine steam, and the calculations of efficiencies.
Even those who do not understand the math will find the text explanations here to be very interesting:
http://www.lesa-maschinen.de/cms/upl...oschuereEN.pdf

By employing Schaeffer's methods, Lloyd's horizontal friction roller device would likely not only be a self-runner, but also be capable of producing a goodly amount of useful work.

Happy reading,

Rick

[Vortex]

I've been playing around with a setup to test some ideas. I looked for a piece of equipment to set up Randy's idea without a lot of hassle. I didn't have anything so I cheated and chucked an oak block in my wood lathe. I turned a ring onto the face of the block with a 5.5in OD and 3in ID. This gives about 16 sq in to equal a 4x4 and the center line of the ring equals about 467 ips at 2100 rpm. I used a 1 gal paint can turned on its side, drilled a hole in the upper side to fill it with water and pushed the top of the can against the ring of wood(the bottom has reinforcement ridges). Some heat at first but disappointing. And once the wood charred the heat output went down!!! Turned the wood clean and it would work until it charred again!!! Wondering what the texture of the metal plays in this, I sanded the top of the can with 120 emery cloth which made big difference! Used 100 grit and now I get small puffs of smoke and even more heat. I got the upper side of the can to 200F. It seems that we need enough "bite" to help shed the carbon but not so much that it wastes wood. I will insulate the can and stir the water to eliminate stratification in the next few days. This should give us an idea of btu output. And only $3 out of pocket so far.

Thank you for trying ..
The charring .. opps , my idea was no so good after all, due to oxygen.

I was just
Randy

[Vortex]

Alternative Steam Engine

It's a simplified version of Tesla's Reciprocating Engine.

If you build it and it works with air, it will work with steam,
providing you used materials that can stand the heat and pressures
of the steam.

Might be cheaper to build and therefore can
build more than one using them back-to-back. Exhaust from
first engine feeds into input of second engine.. and a 3rd engine or 4th?

No need to repost everything here.
I've already posted the details here.

Have fun and Keep on
Randy

[rickoff]

To Randy:

Thanks Randy. Excellent info.

For those reading this post, the Tesla Air Engine Plans are in two pdf files. The first file is a single page cover for the report, and the second pdf is the actual 99 page plan document.

cover page: http://www.aircaraccess.com/pdf/taep%20cover.pdf
plans: http://www.aircaraccess.com/pdf/taep.pdf

If you find the plans useful, please make an appropriate donation by clicking the Donate button at this link: Pneumatic Options Research Library: Download pdf files

Randy - I was just reading your thoughts about an experiment you plan to do this weekend:

I'm looking into how I can create the piston out of epoxy resin for air testing.
I've selected 1" pvc for the piston, which I'm thinking I'll fill with epoxy,
and 1 1/4" pvc for the cylinder. The shaft might be the water meter valve off/on
tool I got at Home Depot for under $4. that will be one solid piece, going through the piston and not treaded.
I do not have a caliber, but the 1" pvc appears to be 1 5/16" O.D.
and the 1 1/4" appears to be 1 11/64" I.D.
I wanted to go with a larger diameter piston but this is what I could
fine first that seems like it should work.
My plans have change a few times already as my "I think" proves to be no good and I have to try a different method.

I'm hoping I can test get it together this weekend and maybe test it
on Monday. Epoxy is ok up to 350 F degrees for steam. Don't know what could be used to mold a piston beyond that temp.

I would recommend using a ceramic adhesive such as Resbond 919, instead of other epoxies, because it will withstand temperatures to 2800F degrees.

As far as the PVC pipe sizes go, you will have a bit of a problem, in that you will have to bore the "cylinder" pipe id a bit larger than your current measurement. If your guesstimate is correct, then the inside diameter of the "cylinder" pipe is 1.179", and the outside diameter of the "piston" pipe is 1.3125, so you will need to remove 0.1335 + from the bore of the "cylinder" pipe. That leaves you a very thin walled cylinder pipe.

Here's a chart showing inside and outside diameters of schedule 80 PVC pipe, and I think you may agree that it looks like a 2.5" piston (2.875" od), and 3" cylinder (2.864 id), would be the best choice for your experiment. You will still need to remove some material from the "cylinder" pipe bore, but removing just .010" from the wall thickness will providing a clearance of .005 inch all around the "piston". The Schedule 80, 3" pipe, has a wall thickness of .300", which is .084" thicker than schedule 40 pipe, and it will withstand up to 370 psi working pressure, which is 110 psi greater than the 3" schedule 40 pipe. It would be a snap for someone to chuck the 3 inch cylinder pipe in a lathe and skim .010" off the inner wall, and will still leave you plenty of wall thickness.

IRazoo - View Site

I hope this helps to get your experiment off to a good start, and please do post any photos and test results here.

Thanks again, Randy. Your contributions are always appreciated.

Rick

[Vortex]

I would recommend using a ceramic adhesive such as Resbond 919, instead of other epoxies, because it will withstand temperatures to 2800F degrees.

Yep, Yep that's hot
I'll have to research that "stuff": price, materials it bonds to, psi or strength
Good info. Thanks.
You (I) have questions like this one often, that you answered which I
wanted to know but wasn't going to start a new topic to find out.

The primary plan is for air testing, the secondary plan is to build it.
I know that's backwards.. meaning figuring out how to build it and that stuff.
Not going to run any steam in it, so pvc is great, I think, it being
air cushioned.

Here's a chart showing inside and outside diameters of schedule 80 PVC pipe, and I think you may agree that it looks like a 2.5" piston (2.875" od), and 3" cylinder (2.864 id), would be the best choice for your experiment. You will still need to remove some material from the "cylinder" pipe bore, but removing just .010" from the wall thickness will providing a clearance of .005 inch all around the "piston". The Schedule 80, 3" pipe, has a wall thickness of .300", which is .084" ticker than schedule 40 pipe, and it will withstand up to 370 psi working pressure, which is 110 psi greater than the 3" schedule 40 pipe. It would be a snap for someone to chuck the 3 inch cylinder pipe in a lathe and skim .010" off the inner wall, and will still leave you plenty of wall thickness.

IRazoo - View Site

I hope this helps to get your experiment off to a good start, and please do post any photos and test results here.

Thanks again, Randy. Your contributions are always appreciated.

Rick

Again, thanks Rick.
Grumble, I should of looked up that chart myself. I was too gun-ho I guess.
I'll be using that table a lot I think.
The 1" fits inside a 1 1/4" without a reduction of either as the chart shows.
Yes bigger is better and I wanted to go with a 2" piston at first, but
I was going to try to reduce anything this build.

Reduction of the piston reduces power so reducing the cylinder as you say
would be best. Since it isn't a large reduction which ever is easier to do
for the builder would be fine. Without a lathe, reducing the piston of 5"
length would be less effort than reducing the 8" cylinder, maybe.
I wasn't even entertain the idea of "reduction".. not on the first build
anyway.

The pvc pipe can't be used for steam, but it could be used
to make a mold in order to cast a piston for steam use?? OH?
So a prototype could be created in pvc, testing with air and then molds
made for casting the steam piston and cylinder providing the casting material
is not real expensive. Casting a piston would be a major construction
reduction if multiple engines are to be put into use, which with waste
steam can easily be done.


Test results?
Dang thing could complete 20 cycles, traveling 30 inches per second, I can't count that fast.
I hopefully can get something together on it, yes.

My shaft is only 1/4" so I'll pass on pumping anything.
Are there any plans laying round for how to generate a little electric power on a linear shaft?

Oh, this engine runs on expansion of the working medium. This expansion
has a fancy name which I forget right now, starts with an A.
Means the air/steam is cut off and allowed to expand in the cylinder and
uses way less air/steam.

Keep on
Randy

[rickoff]

Handy chart, isn't it...

The 1" fits inside a 1 1/4" without a reduction of either as the chart shows.
Randy

Yes, that will work fine in schedule 40 pipe. You could also do it with no reduction using 1.5" inside a 2" pipe if using schedule 80, and that would give you .013" clearance, whereas the clearance will be a whopping .045" if you use the 1" and 1.25" pipes in schedule 40. The next step up in schedule 40 which may be useful is the 3" and 3.5" combo, which gives a clearance of .021"

Filling the entire piston with Resbond could get expensive, but I'm sure you could figure a way to just plug the pipe ends to a depth of 1/4" or so.

If you know of someone nearby who has a lathe, they might be willing to skim cut some larger schedule 80 for free if you offer them a copy of the air engine plans. Just a thought -

Rick

[Vortex]

All-Thread idea

I'm not ignoring you Rick, I'll get back to your previous post later.

The engine has a 8" cylinder, 5" piston and 0.75" left / right travel.
This gives 0.75", at each end, air spring length to play around with.
The piston heads (ends) do not have to be flat!!
With for air, Not for steam in mind I ask these questions.

How could one use all-thread as a shaft?
I had initially bypassed this idea but after evaluation of the alternatives
it seems the easiest way if it could be done.

What part, a sleeve, could be used at the cylinder ends to cover the
all-thread to make it smooth between the cylinder and the shaft.
Only needs to be 1" long.
Is there a way to make the shaft through the cylinder end, self-centering?

What parts would allow self-centering of the shaft inside the pvc piston
as nuts are tighten down upon it?

Talk about easy. How can this be done?
Help Help.
Should I start a new Topic, what would I call it?

Just Hoping
Randy