New small end bronze bushing installation, swaged/burnished or not ?

[Eagle1903]

Thank you very much Modok,
Thank you very much Bill,

First I will make sure the equipment is correct. I may need to buy a new mandrel set to hone 20.63 mm which is majority of the rods I will be working with, then the 24.00 mm set. I am not yet sure what is the range of mandrels.
I will also have to buy coarse and fine stones.

Modok,

You mentioned about the hone length vs the work piece length. Does this mean that, there are different length of mandrels and stones ( and shoes ) for a given diameter range ? ( short mandrels vs long mandrels and their stone/shoes )

I was using Sunnen’s cylinder hone oil in the rod hone. Is it totally wrong ?

Bill,

As you mentioned, it will take a lot of practice to build some experience. I am starting to understand this !!!
Definitely, not an easy job. Lots of engine builders and machinists even do hone pin bores in the pistons and the clearance is very fine there. That must be extremely difficult and needs a lot of experience to attempt I guess.

Since we are at least 8-10hrs apart I may not be able to reply fast.

Many thanks

[BillK]

Thank you very much Modok,
Thank you very much Bill,

First I will make sure the equipment is correct. I may need to buy a new mandrel set to hone 20.63 mm which is majority of the rods I will be working with, then the 24.00 mm set. I am not yet sure what is the range of mandrels.
I will also have to buy coarse and fine stones.

Modok,

You mentioned about the hone length vs the work piece length. Does this mean that, there are different length of mandrels and stones ( and shoes ) for a given diameter range ? ( short mandrels vs long mandrels and their stone/shoes )

I was using Sunnen’s cylinder hone oil in the rod hone. Is it totally wrong ?

Bill,

As you mentioned, it will take a lot of practice to build some experience. I am starting to understand this !!!
Definitely, not an easy job. Lots of engine builders and machinists even do hone pin bores in the pistons and the clearance is very fine there. That must be extremely difficult and needs a lot of experience to attempt I guess.

Since we are at least 8-10hrs apart I may not be able to reply fast.

Many thanks

What Modok meant about the mandrel length is that you should be using the shortest mandrel for doing rods. I think the stones are about 2" long.

The Sunnen honing oil is fine.

[agertz1]

Hard bronze bushings without steel shell. How thin of wall is safe ? Pankl ti rod with 22mm finish bore.
Thanks, Art.

[Eagle1903]

Thank you very much Modok,
Thank you very much Bill,

First I will make sure the equipment is correct. I may need to buy a new mandrel set to hone 20.63 mm which is majority of the rods I will be working with, then the 24.00 mm set. I am not yet sure what is the range of mandrels.
I will also have to buy coarse and fine stones.

Modok,

You mentioned about the hone length vs the work piece length. Does this mean that, there are different length of mandrels and stones ( and shoes ) for a given diameter range ? ( short mandrels vs long mandrels and their stone/shoes )

I was using Sunnen’s cylinder hone oil in the rod hone. Is it totally wrong ?

Bill,

As you mentioned, it will take a lot of practice to build some experience. I am starting to understand this !!!
Definitely, not an easy job. Lots of engine builders and machinists even do hone pin bores in the pistons and the clearance is very fine there. That must be extremely difficult and needs a lot of experience to attempt I guess.

Since we are at least 8-10hrs apart I may not be able to reply fast.

Many thanks

What Modok meant about the mandrel length is that you should be using the shortest mandrel for doing rods. I think the stones are about 2" long.

The Sunnen honing oil is fine.

I understood.

And I will still be able to do 2 rods together.

Then probably the same short mandrel will not be able to do the pistons ( it will be too short for the pistons )

Since I have never bought a rod hone mandrel ( I have a quite a few which came with the machine ) I don’t how the system goes.
I will find that out.

[fabr]

im with bill, no on loctite,always thought it was a heat barrier. yes on the right press fit. i'd try heating the rod. doesnt need much and we do it all the time with stock stuff. tried liquid nitrogen on cyl sleeves for a time but they moved around under operation.

I hate to hijack but could you briefly explain why that would occur? Were you needing to use too little interference fit to allow enough time to be easily slipped in place before warming and expanding?

[modok]

I may be jumping too far AHEAD.
First you need to get it working correctly and see what that's like. It should be possible hone a bushing so perfectly so it's actually rounder than the average piston pin.
When the hone is PERFECT then you can straighten out quite a few messed up holes, but in the process of that you may screw up the hone, and then to fix it you might have to just hone SOMETHING, a truing sleeve or whatever, to get it back in shape again.
You can hone things round, you can hone the OD of a shaft round, you can lap things flat, you can lap things curved like telescope lenses, you can make balls like ball bearings, all similar random abrasive processes where the work and the tool wear eachother to be the perfect shape WHEN the ratios are right.

no matter how many honing mandrels you have, you will still inevitably run into situations where the stones or shoes end up worn unevenly, and no way of stroking or amount of overstroke can solve it.
so.... why?
And the reason why has to do with either the ratio of length not being ideal, or it could be oil distribution, or workpiece flex, or not being able to use enough overstroke.

And if you understand it, there are a lot of tricks you can do about it to adjust things back the other way.

[Dan Timberlake]

My theory is plastic loctite conducts heat better than air.
Similar to why my brand new hot rod CPU would have kept the smoke in way longer than 45 seconds if I had not tried to salvage the old CPU thermal paste.
Yeah CPU surface finishes and contact pressures are way different (wimpier) than well installed pin bushings (no skiving beautiful bronze slivers allowed).

I keep meaning to try a garage science project to see if I still feel the same about Loctite afterwards.

Thermal conductivity W/mK
Steel 45
Loctite 262 0.1
Air 212°F 0.03

https://datasheet.octopart.com/26221-Lo ... 521451.pdf

[Eagle1903]

I may be jumping too far AHEAD.
First you need to get it working correctly and see what that's like. It should be possible hone a bushing so perfectly so it's actually rounder than the average piston pin.
When the hone is PERFECT then you can straighten out quite a few messed up holes, but in the process of that you may screw up the hone, and then to fix it you might have to just hone SOMETHING, a truing sleeve or whatever, to get it back in shape again.
You can hone things round, you can hone the OD of a shaft round, you can lap things flat, you can lap things curved like telescope lenses, you can make balls like ball bearings, all similar random abrasive processes where the work and the tool wear eachother to be the perfect shape WHEN the ratios are right.

no matter how many honing mandrels you have, you will still inevitably run into situations where the stones or shoes end up worn unevenly, and no way of stroking or amount of overstroke can solve it.
so.... why?
And the reason why has to do with either the ratio of length not being ideal, or it could be oil distribution, or workpiece flex, or not being able to use enough overstroke.

And if you understand it, there are a lot of tricks you can do about it to adjust things back the other way.

Hi Modok,
I understand you very well.
I will start by checking all the mandrels I have and try to locate the correct one firstly to hone the small ends of the rods. I will try to develop my skills first on the small ends. Then, I will switch to big ends and then the piston’s pin bores. Like the most engine builders I would like to be in control of honing these 3 holes first.

It is definitely going to take some time to get to an acceptable level.

I am planning to post the photos of some of my mandrels to find out if they are correct for above mentioned jobs. I may not be posting within next week since we will be preparing and traveling for a rally outside our town next weekend.

[BCjohnny]

I was using Sunnen’s cylinder hone oil in the rod hone. Is it totally wrong ?

A long time ago I was advised to run MB-30 ('cylinder hone oil') in the CV616 and MAN-845 in the 'rod hone'

I've done it ever since and have no reason to doubt that advice ...... others might disagree

[modok]

Take a cam bearing, it could be a rod bushing, it could be a cup plug, or a solid plug, whatever. A round thing pressed in a hole.
Drive it in the hole, then drive it out of the hole.
Take a look at the surface.
You sometimes see score marks on the OD, sometimes you don't.
Sometimes several patches of big ugly score marks. Sometimes there are many FINE uniform score marks.
No big surprise.
Tho... predicting if it's going to do that or not, is not so easy. Something to do with fit, friction, surface profiles, surface oxides?

--The friction and scoring tendency of... LUBRICATED, clean, and freshly machined surfaces, is very predictable and uniform--
This is far more important statement than it appears. I was thinking of saying it twice, but, you can read it twice or three times if you want.

The farther we get away from that the less predictable it becomes. If the parts have some oxide on them, that could reduce friction or it could increase scoring.
Why do we DE_GLAZE CYLINDERS? The glaze is oxide.
If the parts are plated, same thing. The plating may reduce friction, it could also tend to "snowball" and make for scoring.
if there is no lubricant, or maybe surfaces that don't let the lubricant work, things get more unpredictable.

One of the three rules of fitting a thing in a hole is.... "Never screw a dry hole" always use a lubricant (or sealant is the lubricant)
Being lubricated with engine oil is the default condition for engine parts unless specified otherwise and I know people think that's odd when I tell them, but oh well it's how it should be.
Sometimes the lubricant makes no difference at all, but sometimes it helps a lot, only thing for sure is MORE predictable with a lubricant than it is without, and so that's why the rule.

But lets talk about this scoring, what does it DO? It CAN act like knerling. Next to the low grooves are high ridges, high ridges that can hold the surfaces apart, and THERE is you heat barrier, THERE is how it "COMES LOOSE" when those ridges smoosh flat again.

Sometimes it isn't a problem, sometimes it is. But it does happen, and I still can't FULLY predict when.

What could we do about it?
One thing you could do is, put loctite on it.

[modok]

So waht does it do?
Is it acting as a lubricant? it is filling the low spots in the surfaces?
Or maybe it is a sealant that prevents the ingress of oxygen or moisture or oil getting IN the gaps.
I don't know why it works for sure.

But IMO, IF the surfaces were fit together perfectly then it would not be needed.
But in reality you press out your old plugs and bushings what do you see? usually only some percentage of true surface contact, scoring, and often weird staining. if it had loctite on it, you will see none of that staining.