# Re: crooked core in cyl casting



## woffler (Feb 7, 2021)

Hello everyone , I am having a issue with a #1Pm research build ,the cyl. bore casting is way crooked before machining , it looks like a egg from left to right and the other end is not bad .
 My concern when i bore this thing it will put all the mating parts ,cyl heads and everything else off of position and i not even how bad the bolt circles would be .
 I went a head and bought another one and it is worse than the first one , any ideas for me to work this out ?


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## larryg (Feb 7, 2021)

Ignoring the cored hole; how does  the out side of the casting look?  If the OD of the flanges are round then you may be able to locate off of the OD and then bore the the cylinder ID concentric from there.  Hopefully the cored hole is not offset so far that you cannot get the bore cleaned up and remove all the rough cast hole.  For me I would have to set that up on a surface plate and do some layout on the flange end with the worst off set and see if you can salvage the casting.  You may have t o overbore and fit a piston to the new bore size.  

I would also be on the phone to PMR and see if they can send a good casting.  I've found they do answer the phone there.

lg
no neat sig line


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## Charles Lamont (Feb 7, 2021)

Do you have enough material to bore it to the correct size, concentric with the exterior, especially in relation to surfaces that will not be machined? In other words, does the casting contain the correctly finished part, with at least some machining allowance, or not? If so it is OK, if not, keep sending them back till you get one that does.


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## woffler (Feb 7, 2021)

I appreciate the replies Gentleman , i thought about offsetting the bore to the top ,i am going to make a bar to just fit the existing hole and see what i come up with ,it might be in there somewhere we will see .

The outside is petty good it may require a larger piston though and rings , I am going to wait and call them Monday and see what they have to say on the issue ,i am sure they have gotten this problem before if i have two of of these bad castings or they have a bad batch, I do not know much about the company .


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## Richard Hed (Feb 8, 2021)

woffler said:


> Hello everyone , I am having a issue with a #1Pm research build ,the cyl. bore casting is way crooked before machining , it looks like a egg from left to right and the other end is not bad .
> My concern when i bore this thing it will put all the mating parts ,cyl heads and everything else off of position and i not even how bad the bolt circles would be .
> I went a head and bought another one and it is worse than the first one , any ideas for me to work this out ?


You can't send them back for replacements for FREE?  Stuart engines would neaver do that.


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## johwen (Feb 8, 2021)

Hello Woffler,
If the OD of the casting is Ok Bore the cylinder oversize until it cleans up then sleeve it back to the correct bore size with a cast iron sleeve. That would be my trick to correct the problem. John


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## Jasonb (Feb 8, 2021)

The core is really only there to save material and *should not *be used as any form of machining reference. Set the casting in the 4-jaw chuck and get the outer edge of the flange to run as true as possible then bore. Provided the core is not excessively off ctr the casting is perfectly OK. 

Another option to set up cored castings is to plug the hole with a bit of wood or similar and then mark the ctr by scribing several arcs from the outer edge and then punch mark the average ctr. Set the punch mark to run true in the 4-jaw.


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## Charles Lamont (Feb 8, 2021)

johwen said:


> If the OD of the casting is Ok Bore the cylinder oversize until it cleans up then sleeve it back to the correct bore size with a cast iron sleeve. That would be my trick to correct the problem.


Woffler should not have to do that. Two castings of questionable quality have been supplied. A misplaced core is not a problem unless it is so far adrift that the part cannot be made *to design*. If careful measurement of the casting shows that it really can't, then it can be classed as scrap, and personally, I would send it back, so that the suppliers understand they are not going to get away with supplying substandard goods. I am not saying these parts are scrap. I don't know how they measure up.
On the other hand, I can well understand if Woffler does not want the hassle, and is prepared to go for a work-around. Castings that are marginal present an interesting challenge to our ability to make a satisfactory part out of them.


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## davidyat (Feb 8, 2021)

*I just went to the PM Research site and looked at the #1 engine. They show a picture of the cylinder casting with a rather good looking bore. Wonder how you got that mismatched one? One solution I thought of was to mic the outside of cylinder, subtract 1.000 inch (bore) and divide by 2. Then you know about what the distance SHOULD be from the edge of bore to the outside edge of the cylinder. Then mic the smallest distance as best you can from the edge of the unmachined bore to outside of the cylinder. If you have more, then I feel you can bore this casting. If not call PM Research.
Grasshopper*


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## Alec Ryals (Feb 9, 2021)

Richard Hed said:


> You can't send them back for replacements for FREE?  Stuart engines would neaver do that.


 I have !


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## terryd (Feb 9, 2021)

Hi Woffler,

I'm not sure where you are based but the  Consumer Contracts Regulations (replaced direct selling regulations in 2014) in Europe and the UK state your rights regarding faulty goods received after remote purchase.  Basically you are within you rights to return the goods for replacement or refund and the sellers must bear the return costs.  I cannot understand why so many people put up with faulty items and then moan about them when there is legal recourse.  

You should not have needed to purchase a second cylinder when the first was faulty it should have been replaced by the company with a non faulty one.  If however it is possible to bore out the cylinder to the original specification on the plans as JasonB suggests it is not faulty.   If you could not machine it to the original specification you should not have to bore oversize or otherwise not follow the original specification it is faulty.  

Anyone who sells remotely (by phone. letter online etc) should know the regs. or should know.   I once had to gently remind a supplier of a faulty product that they had to bear the cost of return and after they initially refused I pointed them to the terms of the regulations and they then had to agree with me.

To quote Which  (my underlining):

_"If you receive faulty goods and wish to return them, the Regulations [CCR] are in addition to your other legal rights.

So, if your goods are faulty and don’t do what they're supposed to, or don’t match the description given, you have the same consumer rights under the Consumer Rights Act (which replaces the Sale of Goods Act from 1 October 2015) as you have when buying in store.

Any terms and conditions that say you must cover the cost of returning an item wouldn’t apply where the goods being returned are faulty."_

As I said these are the regulations in the UK and Europe (even after Brexit) but I am sure that most other jut=risdictions will have similar so my advice is to research your rights.

TerryD


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## MacKendrick (Feb 9, 2021)

Got a bad Casting from Stuart in England. Sent them an email with a picture and they sent a new casting. No problem. PMR is a good company they should do the same with those picture.


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## davidyat (Feb 9, 2021)

*Terry,
   I've always been amazed these days at what people are accepting as acceptable work! I feel that the younger the person, the more they complain. Is it possible, at least here in the States, that the "participation trophy" and "me" crowd weren't taught how to work for what they get? A lot seems to be given to them, they don't have to work for it. But I always will remember what my late wife taught me, "There is no such thing as an absolute". I have come across some young people that are very hard workers.
Grasshopper*


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## Richard Hed (Feb 9, 2021)

davidyat said:


> *Terry,
> I've always been amazed these days at what people are accepting as acceptable work! I feel that the younger the person, the more they complain. Is it possible, at least here in the States, that the "participation trophy" and "me" crowd weren't taught how to work for what they get? A lot seems to be given to them, they don't have to work for it. But I always will remember what my late wife taught me, "There is no such thing as an absolute". I have come across some young people that are very hard workers.
> Grasshopper*


I must be VERY young as I complain a nd wine all day and night


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## woffler (Feb 9, 2021)

Thank you all for helping ,what a response i am humbled , i would like to thank all who replied ,i spoke with Pm research they were very nice and asked me to send back the casting ,but in the same breath they told me they did not have a replacement as these engines are on backorder .

 So i  decided to make a line boring bar , just got the 3/16 square insert for the bar today and will make one up, i have a milling attachment for my lathe and the cylinder will fit into the saddle that will give me a up and down axis to align with .

I have .78 hole on one end and a .54 on the other ,yes nothing is very good about this casting ,it's kind of the perfect storm of defects .

  At this point it's go big or stay home i guess ,this is the only thing i could think of to try and get a true bore thru this thing wish me luck and the Best to you and yours ,i will report back on the progress .
  Thank You


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## Jasonb (Feb 10, 2021)

> I have .78 hole on one end and a .54 on the other ,yes nothing is very good about this casting ,it's kind of the perfect storm of defects .



Whether a parallel or tapered core is used is not a defect, neither as has been said is the position of the core PROVIDED you can get the desired central hole out of the part

Easiest way to tell if it is usable is to measure the OD of the cylinder ends in a few places and average out a size. Then subtract the finished bore from that size and divide by two. Now measure the casting where the core is closest to the edge and if that is less than the calculated wall thickness you will have problems, if not just get on and machine it.


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## TubeTech (Feb 10, 2021)

I had to do the plug of wood technique on me Pmr cylinder Works perfectly well with no hassles.


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## L98fiero (Feb 10, 2021)

davidyat said:


> *I feel that the younger the person, the more they complain. *


A while ago I heard someone else complain about the younger generation, the kids these days, so I looked for the earliest reference I could find, "Our Earth is degenerate in these later days; there are signs that the world is speedily coming to an end; bribery and corruption are common; children no longer obey their parents; every man wants to write a book and the end of the world is evidently approaching." from a Assyrian tablet, 28th century BCE - Smithsonianmag.com, Ten Notable Apocalypses That (Obviously) Didn’t Happen. As pointed out, after that complaint, the Assyrian Empire lasted another 1800 years.
Maybe it's not all the younger generation, just from where you're looking at it, I know some really great, super intelligent and smart younger generation people. The thing I've suggested to many of the complainers is that our generation taught them to be the way they are so I tend not to complain too much.


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## terryd (Feb 10, 2021)

Jasonb said:


> Whether a parallel or tapered core is used is not a defect, neither as has been said is the position of the core PROVIDED you can get the desired central hole out of the part
> 
> Easiest way to tell if it is usable is to measure the OD of the cylinder ends in a few places and average out a size. Then subtract the finished bore from that size and divide by two. Now measure the casting where the core is closest to the edge and if that is less than the calculated wall thickness you will have problems, if not just get on and machine it.


Hi Jason, 

I'm not sure if you read my post but as I said then:

"_If however it is possible to bore out the cylinder to the original specification on the plans as JasonB suggests it is not faulty. _"

TerryD


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## terryd (Feb 10, 2021)

L98fiero said:


> A while ago I heard someone else complain about the younger generation, the kids these days, so I looked for the earliest reference I could find, "Our Earth is degenerate in these later days; there are signs that the world is speedily coming to an end; bribery and corruption are common; children no longer obey their parents; every man wants to write a book and the end of the world is evidently approaching." from a Assyrian tablet, 28th century BCE - Smithsonianmag.com, Ten Notable Apocalypses That (Obviously) Didn’t Happen. As pointed out, after that complaint, the Assyrian Empire lasted another 1800 years.
> Maybe it's not all the younger generation, just from where you're looking at it, I know some really great, super intelligent and smart younger generation people. The thing I've suggested to many of the complainers is that our generation taught them to be the way they are so I tend not to complain too much.


Hi,

there are many similar quotation qoutations attributed to famous writers and teacher of the past such as:
Aristotle about 332 BCE

_They [Young People] have exalted notions, because they have not been humbled by life or learned its necessary limitations; moreover, their hopeful disposition makes them think themselves equal to great things -- and that means having exalted notions. They would always rather do noble deeds than useful ones: Their lives are regulated more by moral feeling than by reasoning -- all their mistakes are in the direction of doing things excessively and vehemently. They overdo everything -- they love too much, hate too much, and the same with everything else._

Hesiod 800 BCE:

_"I see no hope for the future of our people if they are dependent on frivolous youth of today, for certainly all youth are reckless beyond words... When I was young, we were taught to be discreet and respectful of elders, but the present youth are exceedingly wise [disrespectful] and impatient of restraint". _

GK Chesterton (Writer) about 1920 attacks both aged and young:

_"I believe what really happens in history is this: the old man is always wrong; and the young people are always wrong about what is wrong with him. The practical form it takes is this: that, while the old man may stand by some stupid custom, the young man always attacks it with some theory that turns out to be equally stupid."_

There are many similar complaints about young people across the ages.  As a teacher of 11 to 18 year olds for many years I actually found that the vast majority can be serious, intelligent and caring and funny, a bit thoughtless and self centred at times perhaps, but on the whole decent.

It was always thus. 

Stay safe and healthy,

TerryD


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## Jasonb (Feb 10, 2021)

I did read you post Terry but it seems Woffler did not hence me quoting a line from his post.


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## awake (Feb 11, 2021)

Richard Hed said:


> I must be VERY young as I complain a nd wine all day and night



Richard, if you *wine* all day and night, how do you stay sober enough to get anything done?



Couldn't resist, sorry ...


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## Richard Hed (Feb 11, 2021)

L98fiero said:


> A while ago I heard someone else complain about the younger generation, the kids these days, so I looked for the earliest reference I could find, "Our Earth is degenerate in these later days; there are signs that the world is speedily coming to an end; bribery and corruption are common; children no longer obey their parents; every man wants to write a book and the end of the world is evidently approaching." from a Assyrian tablet, 28th century BCE - Smithsonianmag.com, Ten Notable Apocalypses That (Obviously) Didn’t Happen. As pointed out, after that complaint, the Assyrian Empire lasted another 1800 years.
> Maybe it's not all the younger generation, just from where you're looking at it, I know some really great, super intelligent and smart younger generation people. The thing I've suggested to many of the complainers is that our generation taught them to be the way they are so I tend not to complain too much.


The snow was whiter when I was a kid (last week).


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## Richard Hed (Feb 11, 2021)

awake said:


> Richard, if you *wine* all day and night, how do you stay sober enough to get anything done?
> 
> 
> 
> Couldn't resist, sorry ...


If one cannot joke about life, one should just roll over and dye.  ( Well, bad try at a silly joke)


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## davidyat (Feb 12, 2021)

*Thanks to everyone who commented on my "young generation" drivel. Sometimes I go off on a tangent without thinking. You have brought me back down to earth when I tend to get on my soapbox. We do have a tendency to focus on the negative. Yes, there are many talented and smart "young" people out there today. Thanks.
Grasshopper*


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## Charles Lamont (Feb 12, 2021)

Grasshopper, would you mind awfully, turning the *bold* off?


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## davidyat (Feb 12, 2021)

Ok, but explain to me why that bugs you. The reason I do it, is so I can see it.
Grasshopper


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## KJE (Feb 12, 2021)

When you set up a casting you always set up to what’s going to be left over .... not the areas you are machining, castings can never be considered to be perfect. A few simple lay out lines will prove if there is enough material to clean up


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## Tim Wescott (Feb 12, 2021)

davidyat said:


> Ok, but explain to me why that bugs you. The reason I do it, is so I can see it.
> Grasshopper



Because it's the text equivalent of shouting, or at least talking really loud.  If we're in some comfortable quiet space, you wouldn't want me making ordinary conversation in a shout; it's the same for bold.

If you need help seeing, there's ways to customize the font on your web browser.  You're kind of at the mercy of the web developer to have made it possible, but search on "style sheets" and "vision impaired".


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## davidyat (Feb 12, 2021)

Thank you, Tim
Grasshopper


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## terryd (Feb 13, 2021)

Sorry accidental posting.


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## terryd (Feb 13, 2021)

Tim Wescott said:


> Because it's the text equivalent of shouting, or at least talking really loud.  If we're in some comfortable quiet space, you wouldn't want me making ordinary conversation in a shout; it's the same for bold.




Hi Tim,

It's usually writing in all capitals that is considered as shouting when writing text such as FAKE NOOS - see here:









						Why You Shouldn't Write in All Caps
					

Writing in all caps is the written equivalent of shouting, which is (generally) considered rude. So, think twice before pressing Caps Lock.




					www.lifewire.com
				




but I can see your point,

Stay safe and healthy

TerryD


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## terryd (Feb 13, 2021)

davidyat said:


> *Thanks to everyone who commented on my "young generation" drivel. Sometimes I go off on a tangent without thinking. You have brought me back down to earth when I tend to get on my soapbox. We do have a tendency to focus on the negative. Yes, there are many talented and smart "young" people out there today. Thanks.
> Grasshopper*


Hi Grasshopper,

If you have difficulty reading or writing in normal size text on a PC screen you can increase the size of the browser by using the 'CTRL - scroll' combination, i.e. hold down the Ctrl key (lower left on most keyboards) then use the mouse wheel to scroll in and out of the text.  Alson firefox there is a + and - to the right of the web address at the top of the browser - you can also use that to increase text size, I use it with online newspapers, some of which have small print.

Stay safe and healthy,

TerryD


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## davidyat (Feb 13, 2021)

Terry,
   Thanks for the info. I just tried it and it really works for me.
Grasshopper


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## terryd (Feb 13, 2021)

davidyat said:


> Terry,
> Thanks for the info. I just tried it and it really works for me.
> Grasshopper


Hi Grasshoper,

Glad to be of assistance, 

Stay safe and healthy

TerryD


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## Eccentric (Feb 13, 2021)

Woffler,

I had the same issue on my cylinder when built this engine.  I just ignored the existing hole, which was obviously offset, but small enough not to impact the finish bore being correctly centered.  I mounted the cylinder in the 4 jaw chuck and indicated off the outside and bored as usual.  You have probably seen this, a great help:  

Good luck, this is a really fun build.


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## Jasonb (Feb 14, 2021)

I think this whole issue is due to some people on Youtube ( not Joe) using a method they have seen someone else use to centre up the cylinder in the 4-jaw without understanding that it will only work with a totally true core which is a very rare thing to find.

Use the traditional method of plugging the end or take average readings off the edge with a dti when setting it up in the 4'jaw both of which will leave the hole in the ctr of the unmachined external surface


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## IanN (Feb 14, 2021)

Hi,

An issue that has not been mentioned is the fact that the external appearance of the bore would almost certainly not match the internal dimensions.

I am currently working on a cylinder casting and took the picture attached:

Dimension in the middle of bore used as a reference - dial reading 100:









Dimension of bore mouth - reading 40 (60 thou, 1.5mm smaller):


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## woffler (Feb 19, 2021)

Hi everyone ,I came up with a solution to the problem of the cylinder bore being off center ,I am boring them
 out to 1.25 or .25 Over ,they would not be usable other wise, in the measurements on the surface plate i came up short and they would also not match up with the valve rod center either as the two are refenced as being on the same center line.
  I ordered two bronze leaded bushings from Mc Master with a 1inch bore same as the piston and .25 wall this should get me in the kitchen eating chicken.

I attached a picture that shows one bore started was messed up now true and a little to go yet and the other one that has not been started yet ,


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## Eccentric (Feb 19, 2021)

Looks like you are on the right track.  Will you still be able to get the steam feed holes to line up at the ends of the cylinder and to the vents in the steam box?   I had an issue with my cylinder (purely cosmetic) and I used some JB Weld and all is good.


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## davidyat (Feb 19, 2021)

What is that bore measuring device? I've never seen one like that. Please, teach me something.
Grasshopper


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## Steamchick (Feb 20, 2021)

Nice one Woffler. I would have suggested a liner - that bush sounds like a simple accurate and practical liner for the bore.
What pressure are you expecting to run at? Maybe you could have simply made oversized pistons? - depends on the minimum wall thickness after you managed to clean-up at 1.25". I would be very careful with the interference dimensions when you fit the liners. The interference develops hoop stresses in the iron body - which is liable to crack or split completely if very thin. If the liner is a "just-about-tight", or sliding fit, (rather than needing a press to fit) then it will be secured from moving by the end caps. Loctite products can help secure a liner - but the wrong one will cure too quickly and may lock the liner in place when "half-in and half-out". So be very careful with the sizes and check interference fit tables for a fit closest to sliding, rather than risk breaking the cylinders. Remember, the bronze will expand more than the cast iron when you get to "steam temperature" - so that also adds to the hoop stress trying to split the cast iron asunder. Having done the calculations to prove a designer picked the wrong "fits" for a component fitted to a car engine block, (Differential expansion and contraction causing cracking of the outer component) I have first hand experience of how this can easily go wrong.
I think for your "fit" I would check calculations, fit tables, etc. Then check the bore ID and liner OD, Hone the bore to suit the fit dimensions for the tables, say for the tightest sliding fit on the liner OD, and then fit the liner with a drop of Loctite added when the liner has been slid 3/4 of the way into the iron cylinder (Only if you want to add any Loctite). As a lad  (1960s) I fitted dozens of liners into diesel engine blocks - after boring and honing the block for the correct fitting dimension for the liner. Then using the hydraulic press (Never a hammer/shock loading!) could "feel" the liner going in with a stick-slip motion - sometimes almost a "groan" but they were cast iron liners in a cast iron block, but were secured from moving by the cylinder head, so an "easy" fit was ideal. Anyway, we had to re-bore the liners to size after fitting to get the size, as the liners were always supplied thicker-walled than after finished boring. But I doubt you should need that extra process.
Keep up the good work!
K2


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## terryd (Feb 21, 2021)

Steamchick said:


> Nice one Woffler. I would have suggested a liner - that bush sounds like a simple accurate and practical liner for the bore.
> What pressure are you expecting to run at? Maybe you could have simply made oversized pistons? - depends on the minimum wall thickness after you managed to clean-up at 1.25". I would be very careful with the interference dimensions when you fit the liners. The interference develops hoop stresses in the iron body - which is liable to crack or split completely if very thin. If the liner is a "just-about-tight", or sliding fit, (rather than needing a press to fit) then it will be secured from moving by the end caps. Loctite products can help secure a liner - but the wrong one will cure too quickly and may lock the liner in place when "half-in and half-out". So be very careful with the sizes and check interference fit tables for a fit closest to sliding, rather than risk breaking the cylinders. Remember, the bronze will expand more than the cast iron when you get to "steam temperature" - so that also adds to the hoop stress trying to split the cast iron asunder. Having done the calculations to prove a designer picked the wrong "fits" for a component fitted to a car engine block, (Differential expansion and contraction causing cracking of the outer component) I have first hand experience of how this can easily go wrong.
> I think for your "fit" I would check calculations, fit tables, etc. Then check the bore ID and liner OD, Hone the bore to suit the fit dimensions for the tables, say for the tightest sliding fit on the liner OD, and then fit the liner with a drop of Loctite added when the liner has been slid 3/4 of the way into the iron cylinder (Only if you want to add any Loctite). As a lad  (1960s) I fitted dozens of liners into diesel engine blocks - after boring and honing the block for the correct fitting dimension for the liner. Then using the hydraulic press (Never a hammer/shock loading!) could "feel" the liner going in with a stick-slip motion - sometimes almost a "groan" but they were cast iron liners in a cast iron block, but were secured from moving by the cylinder head, so an "easy" fit was ideal. Anyway, we had to re-bore the liners to size after fitting to get the size, as the liners were always supplied thicker-walled than after finished boring. But I doubt you should need that extra process.
> Keep up the good work!
> K2


Hi,
Just a thought, if the liner is left 'loose' in the outer casting (i.e. without loctite or some locating method) is there not a possibility of the steam ports getting out of alignment if the liner were to rotate?  As you quite rightly say if the fit is a tightish frictional one differential expansion of the components could cause problems. 

 Just did a quick check as my memory is not what it was and saw that the coeffiecient of thermal expansion are greater for bronze than cast iron  - around 1 1/2+ times, so as you say a look at the fits tables might be prudent to prevent cracking the thin  shell..

Stay safe and healthy,

TerryD


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## IanN (Mar 20, 2021)

davidyat said:


> What is that bore measuring device? I've never seen one like that. Please, teach me something.
> Grasshopper



Hi David,

Sorry for delayed response.  The device is home-made.

Not my design, the original appeared in Model Engineer magazine some time in the seventies.  I did not own the magazine but thought the design interesting so scribbled some notes and sketches in my notebook and used them as a basis for the version I built some time later (changes to design occurred to fit in with locally available materials, contents of scrap bin, etc at the time)

I can post you some better pics and some drawings if you like.

All the best,
Ian


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## Gordon (Mar 20, 2021)

IanN said:


> Hi David,
> 
> Sorry for delayed response.  The device is home-made.
> 
> ...


I certainly would like to see some more detail on your device. I see the general concept but it would be nice to not have to reinvent the wheel.


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## Poppy Ott (Mar 20, 2021)

Gordon said:


> I certainly would like to see some more detail on your device. I see the general concept but it would be nice to not have to reinvent the wheel.


I would like that as well.


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## Rotormac (Mar 21, 2021)

The original design was by L C Mason and appeared in the Model Engineer magazine for January 4th 1980.


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## Gordon (Mar 22, 2021)

Rotormac said:


> The original design was by L C Mason and appeared in the Model Engineer magazine for January 4th 1980.


Thank you. It turns out that I have a CD that I purchased some time back with back issues of Model Engineer and it has that issue included so I printed it. Not sure what copyright issues are on these.


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## Jasonb (Mar 22, 2021)

CD is breach of copyright and posting here would be too.


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## Rotormac (Mar 23, 2021)

Written copyright extends for 70 yrs after the death of the author.
I've modified LC's design slightly to accommodate the dial gauge I had and I'll happily post drawings of the principal parts of my unit.
The only tricky bit is the main plate.  Getting the geometry correct is tedious but fun.


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