# Sb Fourteen-hit A Snag



## Kroll (Dec 24, 2016)

Guys on my SB Fourteen project I was on a good roll,everything was going smooth until today.I am posting my problem separate from my restoration project cause I just want it to be a good clean post.My problem is the bushing that is for the gear that pivots that drives the QCGB.The bore of the gear is .757 and the bushing OD is .744 and its alittle rough kinda like no oil was ever added.Bushing is part#25 and the gear is #24.Anyway I think I have couple choices:1)Is to try and make another bushing or 2)Bore the gear alittle bigger and turn the OD of the bushing down alittle so that maybe I can get one of those oil embedded sleeves and press it in.Guys it seems to me that SB should have design these parts to have a sleeve so that over time it could be replace but I'm sure there's a reason why they did not.Anyway guys I don't have much experience with these type of issues,I don't know what the gear is made of nor do I know what the bushing is made of.If its mild steel then maybe I stand a chance.I really would like to go with the oil embedded sleeve cause its alittle more forgiving than steel against steel.If you have any ideals or suggestions please let me know,cause I do know that SB parts are out of price range.Thanks  kroll


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## coffmajt (Dec 24, 2016)

the gear should be cast iron, with the bushing steel.  If I were in your position I would ream the gear to a new ID and then make a bushing to fit.  Cast iron usually runs for a long time on steel with minimal lube required because of its high carbon content.  Keep us posted on progress = Jack


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## Chuck K (Dec 24, 2016)

coffmajt said:


> the gear should be cast iron, with the bushing steel.  If I were in your position I would ream the gear to a new ID and then make a bushing to fit.  Cast iron usually runs for a long time on steel with minimal lube required because of its high carbon content.  Keep us posted on progress = Jack


Sounds like good advice. If that's the worst of your problems, your golden.


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## woodtickgreg (Dec 24, 2016)

What the guys above said.


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## Kroll (Dec 25, 2016)

Thanks guys,we now have a plan which leads me to ask another question be posting over in the Beginners Forum and that's about reamers???


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## Brain Coral (Dec 25, 2016)

Hi Kroll 

Merry Christmas... 

Like the others have mentioned, the gear is cast iron and the shaft is steel. This is a very good combination of materials, if properly lubricated. If you have a 4-jaw chuck on your other lathe (do you still have the Colchester ? ) you could indicate the gear true and just bore it to size, then make a new steel shaft with a nice sliding fit. If you simply try to ream the gear bore, it might not end up concentric if the hole has been wallowed out.

Brian


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## Bob Korves (Dec 25, 2016)

First bore, slightly undersize, then ream.  You can bore it start to finish, but it is devilishly easy to overshoot your target bore size...

A reamer will not move a hole, only enlarge it.


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## Kroll (Dec 26, 2016)

Thanks guys for all the comments,I now understand that the combination of cast iron and steel was not one of those value engineer designs but well though out plan.I never knew that,after all this lathe and others SB lathes have lasted for yrs.Guys I posted my question about reamers over in the beginners section(I am) and receive lots of good comments so between learning about the combination of cast iron/steel and reamers how to use them so my small problem has done more good than the problem itself.Like I was told by someone "Calm seas never made a good sailor"
So something that I first though was negative has turned into something positive thanks to the membership.----kroll
Brian,yes sir I do and have a 4jaw chuck which I finish getting the head align bout month ago.But not much tooling for it yet.The bore is good though about halfway then its rough,so I may try to see if I can get the gear perfect and just take a cleanup cut then use a reamer.


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## Brain Coral (Dec 26, 2016)

Hello Bob 

I am wondering why a reamer would be a part of Kroll's situation. The way that I see it, he has a rough and bad fit between his cast iron gear and his steel shaft. If the gear is bored even slightly, it will require a new shaft turned to the new diameter. Would the reamer provide a better finished hole than boring?

No disrespect, but I would simply bore the gear to a nice and symmetric hole, and then turn a new shaft carefully, to fit the bored hole.

Brian


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## Bob Korves (Dec 26, 2016)

Yes, Brian, I misunderstood the issue.  Your answer to make a new shaft was correct, or an added bushing would also work.


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## Kroll (Dec 27, 2016)

Thanks guys,reading ya'll post and talking about it I see that really there are several ways to make a hole repairs which its nice to have choices.If I may borrow Brians ideal and chuck up the gear and put a dial indicator on it and just see how it goes.If I'm able to get it lined up then will proceeded to bore just to clean it up.Next make a new bushing to fit the bore what ever size that maybe.Either way this problem is a learning experience about the materials,reamers,just plain ole machining.Been watching Youtubes on reamers so now I kinda understand there is a place for them even in my hobby type shop on a as need bases.I really like the ideal of reaming a hole to become a press fit,slip fit,like a hole for one of those oil hole covers.Guys I won't be making those repairs for afew days,I have so much of the lathe laying around I want to get it put back together as far as I can go then concentrate on the repairs.Thanks so much for all the help and keeping it simple for someone like myself so that I understand.Progress is being made ---kroll


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## Kroll (Jan 16, 2017)

Guys my Colchester is kinda tied up with the hand wheel project.So I am using my Atlas lathe to bored out the gear with the help of WreckWreck and it now has a good smooth finish.So I remove my big chuck and installed my small Atlas chuck.Now I am ready to start on the bushing,using a piece of steel that was part of a care package that someone give to me I am now ready to start on it,till I get to needing a reamer for that perfect smooth fit.Can you see the bushing in my scrap piece of steel?Back to being positive ---kroll


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## Chuck K (Jan 16, 2017)

You should be able to complete the job with the boring bar.  Just sneek up to your dimension.


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## Kroll (Jan 18, 2017)

Chuck I did take your advice and sneek up on the OD.If I paid myself bout 5.00 hr I still would be way to expensive cause it took awhile to fit the OD to the bore of the gear.But so far I am happy with it,I did drill out the bushing for the bolt that has an OD .490 so I will take a reamer and do a clean up cut to size.So far so good but not out of the woods yet----kroll


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## Chuck K (Jan 18, 2017)

It appears that your gear has a chipped tooth.


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## Kroll (Jan 19, 2017)

It does and it matches a 4 jaw chuck,not mine.Every 15 teeth there is a small chip,so someone has work on this lathe before.But other than that all the other teeth look very good on that gear,and the teeth look goood on all the other gears also.I don't think this lathe was use that much,which it did come from a school district---kroll


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## Chuck K (Jan 20, 2017)

If that's the only damage the students did you're in good shape.  The ways usually don't have much wear on school machines. Sometimes they're kind of nicked up.  I had a logan 10" that came from a school.  I have never seen so many broken gears on one machine. After all the repairs were done it was a pretty nice machine.


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## Kroll (Jan 23, 2017)

Good afternoon guys,I have good news.My snag is no longer a snag,I am one happy camper.Guys I got home this afternoon and check my mail,the reamer that I order had come in which it has an OD of .495 which will allow the bolt to be a slip fit I guess.Anyway so off to the shop to ream out the hole and see if the bolt will fit or not,and I be dang it fits and no wiggle at all.Once I flip the part around to use my parting tool for the first time for me,it went pretty well.I did take couple little five min breaks to give all a chance to cool down.Using oil on the parting it also went well just pop right off and smooth.I did allow to face to a finish thickness which had to remove another .035.So guys I finally made something that had to fit no if/ands/buts it just fit,the finish is not fantastic but smooth to the touch and the edges are razor sharp.So now I can move on to my next hurdle which will be the knob for adjusting the reeves pulley and doing all the electrical so hope that goes well.One day guys I will learn how to post pics and explain each pic.Thanks for looking ---kroll


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## Chuck K (Jan 23, 2017)

Looks good!


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