Stuart 10H build

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wce4

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My new project is the Stuart 10H is a development from the popular 10V Engine. I purchased the casting set about four years ago at the Consignment Sales Area of Cabin Fever Model Engineering Expo Show.This will go nice next to my Stuart 10V that I finish about a year ago. First up the boxbed. Not that much machining on this part. The boxbed casting was very clean and flat. Light cut on top and bottom Drill 6 holes, tap 4 holes 7ba., two clearance holes for for mounting.
 

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Work on the soleplate today, had to do a lot of fettling
on this casting. But at the end it turn out ok.
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Do you have any photos of how you machined those lands for the bearings? I have the same project, but since my mill is not in operation this is a problem for me. I have several possible methods and since I now have a milling attachment, it is always possible to use it for straight across milling with a ball end mill. but I'm curious how yhou did it.
 
Do you have any photos of how you machined those lands for the bearings? I have the same project, but since my mill is not in operation this is a problem for me. I have several possible methods and since I now have a milling attachment, it is always possible to use it for straight across milling with a ball end mill. but I'm curious how yhou did it.
Sorry I do not, but I can tell you I use a 7/16 ball end mill on the mill so that is not going to help you. I am sure there are other on here that can give you better suggestion than I can. I am just a retired old seabee trying to be a model engineer and not very good at it.
 
Do you have any photos of how you machined those lands for the bearings? I have the same project, but since my mill is not in operation this is a problem for me. I have several possible methods and since I now have a milling attachment, it is always possible to use it for straight across milling with a ball end mill. but I'm curious how yhou did it.
Don't think this will help much, but I did mine with my Burke #4 horizontal mill.
 

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Don't think this will help much, but I did mine with my Burke #4 horizontal mill.
That would certainly be my preference but I don't have a horizontal mill. A regular mill could accomplish it but all I fhave at the moment is a milling attachgment. I thimpfk I could mount the part on the cross-slide and mill it that way if I can get the proper sized cutting tool.

BTW, I was looking at Grizzly mills and I wanted one, a BP style with a horizontal. At the time it was about 7000$--now more. I just couldn't afford it. But I knew I would be able to use it's functionality. I've got a couple cutters that might be the right size--will have to check.
 
The brass extrusions are not a perfect "D" shape so all you really need do is mill the upper half of the slot to *7/16" wide and use a round file to shape the bottom so it clears the extrusion

* check width of extrusion and mill slot to that.

Also if it is a new set of castings you will have been supplied with the bearings as a sand casting not the traditional brass extrusion so they will need more clean up which will also affect their size and profile.
 
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The brass extrusions are not a perfect "D" shape so all you really need do is mill the upper half of the slot to *7/16" wide and use a round file to shape the bottom so it clears the extrusion

* check width of extrusion and mill slot to that.

Also if it is a new set of castings you will have been supplied with the bearings as a sand casting not the traditional brass extrusion so they will need more clean up which will also affect their size and profile.
All of that stuff is one problem but how do you center the bearing to bore it?
 
That is why I said check the width of the the bearing and machine the slot to suit. That way it will locate against the two vertical edges of the "U" shaped slot.

The alternative is to bin the supplied bearings and machine a rectangular pocket and fit proper split bearings with retaining plate. Same as this 10V
 

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That is why I said check the width of the the bearing and machine the slot to suit. That way it will locate against the two vertical edges of the "U" shaped slot.

The alternative is to bin the supplied bearings and machine a rectangular pocket and fit proper split bearings with retaining plate. Same as this 10V
Jasonb I really like your Idea on machining a rectangular pocket and fit proper split bearings with retaining plate. From where I'm sitting it looks better than the original design. I might just change it on my engine after I finish it as design. 🤔 Thank you.
 
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Looks very nice !
Sometimes, just succeeding in correcting mistakes is enough , and that makes us happy .
 
I have 3 Stuart D10s. In 2 of my Stuart D10 has all the outer bearings are not in full contact with the frame bearing and the middle bearing is 2 split and the lower bearing can be adjusted with shims until the bearings are held together without slack if it is not perfectly machined in line on the frame bearing (or socalled sole plate). The bearings are only on top of the machined frame bearing and are in line all the way through. The mounting holes on the bearings should be slightly larger than the stud bolts so that the bearings can fit laterally on the crankshaft when the nuts are tightened. What is important is that the crankshaft rotates freely with very little slack. In the event that the crankshaft is a bit tight, running-in means that the bearings are adapted to the correct tolerance. As long as the crankshaft and bearings have been in order for several years, there is no reason to dismantle the bearings/crankshaft as long as the bearings are well lubricated. Dismantled only when the crankshaft/bearings need to be overhauled if they are worn down for natural reasons.
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Stuart D10 with mechanical lubricator and heater for feeding water (heated by exhaust) before feeding to boiler for long running. Still a bit work before mounting in the tugboat.
 
I have 3 Stuart D10s. In 2 of my Stuart D10 has all the outer bearings are not in full contact with the frame bearing and the middle bearing is 2 split and the lower bearing can be adjusted with shims until the bearings are held together without slack if it is not perfectly machined in line on the frame bearing (or socalled sole plate). The bearings are only on top of the machined frame bearing and are in line all the way through. The mounting holes on the bearings should be slightly larger than the stud bolts so that the bearings can fit laterally on the crankshaft when the nuts are tightened. What is important is that the crankshaft rotates freely with very little slack. In the event that the crankshaft is a bit tight, running-in means that the bearings are adapted to the correct tolerance. As long as the crankshaft and bearings have been in order for several years, there is no reason to dismantle the bearings/crankshaft as long as the bearings are well lubricated. Dismantled only when the crankshaft/bearings need to be overhauled if they are worn down for natural reasons.View attachment 151693View attachment 151694View attachment 151695

Stuart D10 with mechanical lubricator and heater for feeding water (heated by exhaust) before feeding to boiler for long running. Still a bit work before mounting in the tugboat.
Love your idea of using the exhaust heat to preheat the input water. All excess heat should be harnessed if possible.
 
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