# Question on split bearing blocks



## Brian Rupnow (Oct 22, 2008)

How does one go about machining a split bearing block like the one shown in the attachment. I assume that you make the two seperate peices without a hole, bolt them together, and then drill and ream the hole on the split line. BUT--I haven't actually done it myself, so I am asking the question.---Brian


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## Mcgyver (Oct 22, 2008)

yup, bolt or solder or otherwise hold together, ream or bore, seperate


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## chuck foster (Oct 22, 2008)

thats the way i would do it..............

chuck


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## wareagle (Oct 22, 2008)

Well, this isn't the proper way of doing it, but... What I have done in the past was machined the two pieces in preparation for reaming the hole. Profiling, drilling, tapping, etc. Once done, I took a sheet of paper, and I placed it between the two pieces and put them together with bolts. Then I drilled and reamed the hole. This gave enough clearance between the two parts to get a bite on the bearing. This job was one of those "in a hurry" deals, and this was the fasted method I could come up with in a pinch. It worked.

I am sure someone else will share a proper method!


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## Brian Rupnow (Oct 22, 2008)

This is for the new double cylinder horizontal steam engine I am designing/building. It represents a bit of a unique challenge because the built up crank will have a center bearing support. Since I have to split the center bearing to get it on the crankshaft, I thought it would be best to split all 3 bearings (inner and outers) for "continuity of design". I was planning on making these bearing stands out of aluminum with a brass bushing, but now, looking at the design I may have to make them from brass and forget about using a bushing.--It gets a bit complex to split the stands AND a bushing.---Of course, I suppose I could make the center stand from brass with no bushing and make the outer bearing stands from aluminum (looks better against the bronze flywheels) and slide a brass bushing on over the ends of the crankshaft.


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## wareagle (Oct 22, 2008)

Brian, excuse my misunderstanding! Just a thought, and I really don't know how well it would work... But what about silver soldering a half round (actually a little more than half round to have enough for machining) of brass/bronze to the stand prior to machining? Then machine and ream in the same fashion as before (leaving the paper out ).

This has the old noodle engaged...


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## Brian Rupnow (Oct 22, 2008)

wareagle  said:
			
		

> Brian, excuse my misunderstanding! Just a thought, and I really don't know how well it would work... But what about silver soldering a half round (actually a little more than half round to have enough for machining) of brass/bronze to the stand prior to machining? Then machine and ream in the same fashion as before (leaving the paper out ).
> 
> This has the old noodle engaged...


Not a bad idea but--If I make the stands from aluminum, silver solder doesn't stick to aluminum. If I make the stands from brass there is no need for a bushing. Perhaps some loctite 648 would do--Hmmmmm


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## wareagle (Oct 22, 2008)

Brian Rupnow  said:
			
		

> If I make the stands from aluminum, silver solder doesn't stick to aluminum.



Holy cow! Duh!!! Man, it has been a l-o-n-g day!!


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## Philjoe5 (Oct 22, 2008)

Brian,
I'm about to make the same thing for the engine I'm building. I'm planning to do something similar to what you have presented. However, I'm planning to make a 3 piece set. A brass cap (your blue piece), its complement below it, also in brass, both of which will be bolted to a steel base. I have no idea if my design will hold up or not, just my $0.02 worth. Importantly, I'm going to make the 3 piece set, bolt it together, before drilling and reaming just as you suggest.

Cheers,
Phil


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## Brian Rupnow (Oct 22, 2008)

Wareagle--Its not such a bad idea really---. I'm thinking of an aluminum end stand, but make it longer at the top, and drill and ream a 3/8" hole, then loctite 648 a round peice of 3/8" bronze into the hole. Wait 24 hours, then mill it down to the center of the brass insert. Same for the aluminum bearing cap. Then bolt the peices together and drill and ream on the split line. Might be a bit of work, but it would give the option of split aluminum bearing stands with split bronze inserts.


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## wareagle (Oct 22, 2008)

Brian, let us know what you decide (I know you will; why do I post stuff like that?? :). Hopefully that will work out. It might be a good idea to test the theory on a scrap piece first!


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## wespe (Oct 22, 2008)

Just going to toss out an idea here brought about by wareagle's method mentioned earlier. If you are going to make AL mounts with Bronze inserts, why not add a rectangle of shim material between the two halves of the bushing? Nothing to thick, maybe 1-2 thou? That way you could loosen the bush if it is a little tight by putting a thicker shim in, or tighten a loose bush by putting in a thinner shim. As well, if this engine sees a lot of use you could reduce the effects of wear on the bush through the shims, and make sure it runs well for a long time.


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## Maryak (Oct 23, 2008)

Brian,

If you opt for bushes in a housing, I suggest you put shoulders on the bushes to stop them walking out of the housings.

Below is crapodad attempt at what I mean, with a couple of housing options.

Best Regards
Bob


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## tel (Oct 23, 2008)

I've used your option 1 a few times Bob - made a little press tool to use in the vise to form 'em out of strip steel.


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## Maryak (Oct 23, 2008)

Gee's Tel,

Your not just a pretty face are you :

Ive machined them out of solid, (me and the top keep). :-\

There are many such gems on this site and thank you for that one.

Best Regards
Bob


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## DickDastardly40 (Oct 23, 2008)

Brian, et al,

If you are making 3 in total, make them from of top and bottom pieces correctly profiled (sorry cant see picture due to work restrictions) which are long enough for 3 plus the width of 2 saw blades plus a little margin. Hold the 2 pieces together with jublilee clips or similar, set up and bore. Saw into 3 and clean up sides, drill holes for fixing. You could drill the fixing holes first and forego the jubilee clip idea.

This method means that you only have to set up for boring once and all 3 will have exactly the same bore diameter and be concentric with each other.

I have used a similar method to make split collets and split bushes.

Hope this makes sense and is of help

Al


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## tel (Oct 23, 2008)

Maryak  said:
			
		

> Gee's Tel,
> 
> Your not just a pretty face are you :
> 
> ...



Photer of the (very rough) tool tomorrow, if you want it

These caps were done with it


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## tel (Oct 23, 2008)

.... and these with a similar one


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## jack404 (Oct 23, 2008)

Hey tel 

that photo WAS taken before '96 and never had a touch hole either EH..

cheers mate

jack


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## Brian Rupnow (Oct 23, 2008)

As of this morning the game plan has changed. I am going to go with ball bearings on the outer 2 bearing stands, and a bushing on the center bearing stand only. The ball bearings in the outer bearing stands will be hidden by the flywheel hubs, as the flywheel hubs are 1" in diameter, while the o.d. of the bearing is only 11/16" and it is 1/4" wide. all 3 housings and caps will have the same physical outer shape and sizes, and all will have the centerline of the shaft the same height from the base. Once assembled, there will be no visible difference between the outer and center bearing stands.


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## wareagle (Oct 23, 2008)

Very cool! You are making good progress on your creation! I for one am enjoying being taken along on the journey, so a big hearty "Thank you" for taking the time to share the adventure with us!!


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## Lew Hartswick (Oct 23, 2008)

As Maryak said. You do know how the main and rod bearing are put in an auto engine. If it were me
id make the inserts narrower than the caps and supports and recess them in a groove. That would not 
even show. Of course the hole in the cap/support must be a triffel larger than the bearing shell.
  ...lew...


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## Bernd (Oct 23, 2008)

Here's another way of doing bearings. Nelson Riedel is has built a Shay locomotive. The link shows how he machined the crank shaft bearings. Something you guys might be interested in. Check out the 7th, 8th, and 9th pics real close. You'll see how he used square bearings with a flange on them, plus lot's of maching ideas.

Nelsons link:http://www.nelsonslocomotive.com/Shay/Engine/EngineMachining/EngineMachining.htm

Bernd


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## rake60 (Oct 23, 2008)

Alignment of the bores may become a problem.
Machining three supports that will bolt to a base and have
perfect alignment would be an impressive achievement.
Doing that is beyond my home shop skills.

I have several supports in my recycle box that I had tried
to make individually. 

When the bores are all the same size I have always found it
necessary to assemble the supports to the base, then drill and
ream them all in one pass using scrap aluminium blocks
as supports between them to eliminate any flex.

The bores being different sizes would complicate that.

Great thread Brian!
Keep it coming.

Rick


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## Brian Rupnow (Oct 23, 2008)

Rick--That is why I modified the way the bearing stands attach to the base. If you compare the model in this thread to the model over in the main build thread, you will see that my earlier version had the outside bearings bolted to the side of the base, while the current version in this thread have all 3 bearing stands bolted to the top of the base. The fact that they all have a common datum serface (the underside) should make bore alignment easier. I may bolt them all to a dummy base side by side and after boring, shift them to the wider "real" base. Flat is flat, (I think). The more I think about this, the crazier I get. I think I will make all 3 bearing stands and caps identical, and make a split peice of bronze the same diameter and thickness as the ball bearing for the center journal.


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## Cedge (Oct 23, 2008)

Brian
The easy way to get them right is to stack them together with a bit of super glue, making an aluminum "Dagwood" sandwich. To make sure all are identical, machine the edges of the sandwich and then locate the bearing hole placement and drill it while the stack is still uniformly stuck together. 

Once you break the sandwich apart, you'll have 3 identical clones. You can then use a simple rod to align things when you are ready to bolt them down to the base. If you happen to miss the mark while drilling the mounting holes, it probably won't be by much. You can, then if needed, use a reamer as a line bore, to bring things back to a gnat's gonads. Much less chance of screwing up than trying to use a drill bit or trying to do them one at a time.

Steve


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## CrewCab (Oct 23, 2008)

Brian ............. I have no technical advice to add, the gang seem to have taken care of that ........... but just popped in to wish you luck and say thanks for your efforts both in machining and posting .......... it's so helpful for all us new guys :bow:

Thanks, I'm enjoying this build very much.

CC


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## Brian Rupnow (Oct 23, 2008)

Cedge  said:
			
		

> Brian
> The easy way to get them right is to stack them together with a bit of super glue, making an aluminum "Dagwood" sandwich. To make sure all are identical, machine the edges of the sandwich and then locate the bearing hole placement and drill it while the stack is still uniformly stuck together.
> 
> Once you break the sandwich apart, you'll have 3 identical clones. You can then use a simple rod to align things when you are ready to bolt them down to the base. If you happen to miss the mark while drilling the mounting holes, it probably won't be by much. You can, then if needed, use a reamer as a line bore, to bring things back to a gnat's gonads. Much less chance of screwing up than trying to use a drill bit or trying to do them one at a time.
> ...


Cedge--Very, very good advice.!!! That is the same as welding the crankshaft throws together with my mig before machining them. I will do that --Thank You.---Brian


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## CrewCab (Oct 23, 2008)

Brian Rupnow  said:
			
		

> Flat is flat, (I think).



Ahh ............ that simple statement could open up a whole new can o' worms Brian :  from your point of view ..... and mine a flycyut lump of aluminium is no doubt just fine as a flat base, but I suspect there may be a little disagreement other opinions.

CC


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## Brian Rupnow (Oct 26, 2008)

This is how it worked out. I'm very pleased with the results. When I get all 3 bolted down securely to a base, I'll let you know how freely it turns.---Brian


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## bentprop (Oct 28, 2008)

looks good to me,Brian.I went a slightly different route with big ends for "bogsy's" twin.I drilled the hole in a flat piece of brass,then separated at centre of bore.But the saw cut meant the hole was no longer round,or the right size.So i silver-soldered bits of brass shim to the Cut ends,bolted them together and bored.The long way around,and not altogether satisfactory .
Next time I'll follow the plan,honest,mister


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## tel (Oct 28, 2008)

CrewCab  said:
			
		

> Ahh ............ that simple statement could open up a whole new can o' worms Brian : from your point of view ..... and mine a flycyut lump of aluminium is no doubt just fine as a flat base, but I suspect there may be a little disagreement other opinions.
> 
> CC



I once made the mistake of bolting down the bearing pillars for the overhead camshaft in a Datsun L18 engine in the wrong order - _that's_ when you learn flat ain't flat.


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## Mcgyver (Oct 28, 2008)

rake60  said:
			
		

> Alignment of the bores may become a problem.
> Machining three supports that will bolt to a base and have
> perfect alignment would be an impressive achievement.
> Doing that is beyond my home shop skills.



excellent point Rick, and a frustrating cause of binding I'm sure for many beginner's engines. A nifty little dodge is to use a bearing scraper and piece of ground precision shafting to get all the bearings absolutely perfectly in the same axis.....lay in the bottom half of the bearing, figure out what one is high and using blue scrape it in then fit the tops. if you've over-scraped and the tops don't make contact, hold a fine file in hand and run the bearing top along it once and try again. perfect, none binding cranks without slop


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