# New To Me, Jet 1336pbd - With Some "issues"



## Steve Shannon (Dec 8, 2015)

A couple weeks ago I found a Jet 1336PBD on Craigslist.  I went and saw it and apparently my eagerness to have something big and heavy clouded my brain.  It has some problems, which probably should have scared me away.  They are (so far):

One broken tooth on the bull gear,
One broken tooth on the pinion on the back gear which meshes with the bull,
Scoring and burrs inside the spindle (MT5),
Lack of fastidiousness; the lathe is filthy, but the ways don't "look" badly worn,
Quick change gear selectors would not move, 
One of the cap screws holding the headstock casting to the bed has broken; the head was just sitting in the hole, and
One of the belt pulleys is broken.
Bit by bit I'm going to begin cleaning up the parts and try to find replacements for for the broken ones.  If I determine that parts from a specific model of another company's lathe are compatible I will document that.  I'm not disciplined enough to do a full rebuild thread, but I will try to post pics once I begin.  That won't be until the spring though as I have way too many other things which I must finish first.
I'm interested in your comments.


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## RJSakowski (Dec 8, 2015)

Hi Steve, Welcome to the group!  It sounds like you will need to apply some TLC to your newly acquired lathe.  You will undoubtedly find someone who has gone through the same problems before you. Don't be afraid to ask.  Whether it be a source of parts or suggestions as to how to tackle a certain tasks.

Bob


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## Steve Shannon (Dec 8, 2015)

Thanks, Bob. I appreciate the encouragement. I've been poring through other posts in hopes of learning of parts sources. One general question I would ask is for suggestions regarding go-no go decisions and what order to approach the rebuild. I'm not looking to make this into a machine that will cut tenths and earn money with, just something I can use to play with. 



Steve Shannon, P.E.


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## brino (Dec 8, 2015)

Hi Steve,

Welcome to the site!

It sounds like your expectations are set correctly. You know this lathe is a "project" now, but after hundreds of invested hours can be a usable lathe.
You are going to learn so much about that lathe as you proceed. You will know it inside out.

-broken gear teeth can be brazed then filed to recreate the tooth profile
-the bigger question is how they broke
-was it at the same time as the headstock bolt and the pulley?  some sudden stop?
-was the lathe dropped? (yikes!)
-what other damage may be lurking?

Please note that NONE of this is meant to discourage you. With slow persistence you can return this abused equipment into a wonderful useful tool!
Do your research, ask lots of questions, and as my Dad has always told me 'do NOT make any big decisions at the end of the day when you are tired/sore/beaten/dejected'.

-light scoring inside the Morse taper can be dealt with by light stoning of the high-spots
-a nice, clean MT5 shank can be blued and used as a gauge to see mating spots
-a MT reamer can deal with heavier scoring (a little expensive for "one time" use, but you may be able to borrow one here.)

-a good cleaning is definitely in order

One other thought.....hit it NOW with some penetrating oil! Shoot every bolt, nut, thread, dovetail, half-nut, sliding gear, etc. Try to do it every 2-3 weeks and by spring you'll be amazed at how easy it is to work on. A 50/50 mix of ATF (Automatic Transmission Fluid) and acetone is my favourite. The mixture is so thin that it wicks into every crevice, the acetone does evaporate quickly but it leaves the oil behind.

Good Luck!
-brino

btw: please post some pictures when you can....even the dirty, broken "before" pictures.


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## Steve Shannon (Dec 8, 2015)

brino,
Thanks for the good words; your list of questions is the same as mine. To me it looks like whatever broke the gears was a different event than that which broke the pulley. I do wonder if the lathe was dropped. I think I should check for spindle damage before I invest a whole bunch of money, but my time is cheap . I didn't see visible runout when the seller showed it to me. I think my next step is to pick up a Mitutoyo DTI and do some basic tests. 
Is this the right forum to document my steps and mis-steps?
I've been shooting WD-40 in every crevice. I may just try your penetrating oil recipe. I interned in a ceramic engineering company and developed a very healthy distrust of acetone except for use in very small quantities. One splash in your eyes and your corneas are permanently cloudy. Of course I will wear safety glasses as I work on this. 
The qc gear levers now slide easily along their shat, but only if I push right next to the shaft. Any force at the end of the lever and it sticks. I suspect wear allows the levers to cock slightly and bind. Does that sound reasonable?



Steve Shannon, P.E.
(Edited to correct auto-correct respelling of "brino".


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## Steve Shannon (Dec 8, 2015)

The Jet BDB-1340, looks very similar. Does anyone know if any of the gears are compatible? 


Steve Shannon, P.E.


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## Steve Shannon (Dec 10, 2015)

For example, the bull gear for the 1336PBD has the same module pitch and number of teeth as the one for the BDB1340. Same for the back gears. The two gears there have the same pitch (MP2) and number of teeth. The drawings, while not exactly the same, follow exactly the same layout, right down to the number in the picture. Now, I know that in 28 years and moving the manufacturing from Taiwan to China there could be insurmountable differences, but I'm encouraged by the similarities. If anyone on this forum has a BDB-1340, I would appreciate exchanging dimensions.  


Steve Shannon, P.E.


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## pdentrem (Dec 11, 2015)

I have Jet BDB-1340A at work and a clone at home. How can I help?
Pierre


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## Steve Shannon (Dec 11, 2015)

Great! Could you tell me the length of the back gears, which is part #04109A. Just a close approximation would be a good start. If it's close to the length of the similar part on my 1336PBD, I might order one from Jet if they allow returns. No hurry, please, I won't order anything until late January. 
Thank you very much!


Steve Shannon, P.E.


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## pdentrem (Dec 12, 2015)

In measuring my clone at home I have approximately 4.9" OAL. When I get to work next week I can measure the Jet BDB-1340 and post that one.


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## Steve Shannon (Dec 12, 2015)

Mine is the same length, but I know my first purchases will need to include good measuring tools. 
Here's mine:




Steve Shannon, P.E.


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## Steve Shannon (Dec 12, 2015)

The pinion, on the right, is about 7/8 inch thick. The gear on the left is 3/4 in. thick. 
Let me know when I start to irritate you. 
Does yours have a zerk?
Also, can you slide the back gears left and right? I don't see a set screw and mine definitely slide, about 1/8 inch or so. 
The problem with mine is this broken tooth:

Thank you very much!
	

		
			
		

		
	





Steve Shannon, P.E.


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## derf (Dec 12, 2015)

I just looked at mine, and it has about 3/16" play from end to end and has a zerk. I've never had it out, but if the need arises I will probably install some shims. If or when you pull the spindle, it would be a good idea to drill some "extra" dog pin holes in the face of the spindle pulley. I had mine get rounded off and ever so often it would slip out of gear, so I drilled 4 holes for the drive pin dog to engage as not to put so much wear on just one hole.


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## Steve Shannon (Dec 12, 2015)

Thanks, derf, I wonder if the design uses the side to side play to equalize the thrust caused by the helical gears. 
I will eventually remove the spindle. Tonight I tried to remove the back gears. I took out the set screws and removed the lever. The bushing on the left end slid out easily. Because of the offset shaft i "think" the right bushing needs to be removed toward the right. I started tapping on the shaft using a block of wood on the left end of the shaft. The bushing on the right started coming out easily, but then stopped. Not wanting to break anything, I stopped. Any suggestions?


Steve Shannon, P.E.


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## Steve Shannon (Dec 13, 2015)

Looking at the BDB-1340A manual/parts diagram, it looks like the eccentric shaft should be able to slide out to the left. I'll try that tomorrow. 


Steve Shannon, P.E.


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## Steve Shannon (Dec 13, 2015)

More pictures of the lathe:



Here's the spindle bore:
Outboard



Inboard view




Steve Shannon, P.E.


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## derf (Dec 13, 2015)

That bushing should be able to go either way, the only thing that holds it is a set screw. It may have a slight burr or mushroom on the side where the gear rubs it.


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## therickster (Dec 13, 2015)

Thats the exact lathe I have in my shop. Mine is a 1989. It will be interesting to see what parts will work in this lathe. I have the original manual for it also.


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## brino (Dec 13, 2015)

Steve Shannon said:


> Tonight I tried to remove the back gears. I took out the set screws and removed the lever. The bushing on the left end slid out easily. Because of the offset shaft i "think" the right bushing needs to be removed toward the right. I started tapping on the shaft using a block of wood on the left end of the shaft. The bushing on the right started coming out easily, but then stopped. Not wanting to break anything, I stopped. Any suggestions?



Did you check for a second set-screw under the first?
That is sometimes done to lock the first one, like grub nuts.
-brino


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## Steve Shannon (Dec 13, 2015)

Brino,
When I first started, one of the set-screws was missing completely. In my poking around I have found some screws missing, broken, or replaced with something "similar". 
I looked in the hole and could see the bushing. On the other end of the shaft I removed the sole set-screw. The bushing that had a set-screw came out easily. The other came out easily about 3/8 inch, then seemed to get tight. 



Steve Shannon, P.E.


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## Steve Shannon (Dec 13, 2015)

therickster said:


> Thats the exact lathe I have in my shop. Mine is a 1989. It will be interesting to see what parts will work in this lathe. I have the original manual for it also.


I'll try to do a better job of documenting my progress then. 


Steve Shannon, P.E.


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## Steve Shannon (Dec 13, 2015)

derf said:


> That bushing should be able to go either way, the only thing that holds it is a set screw. It may have a slight burr or mushroom on the side where the gear rubs it.


That makes sense to me. Thanks, again. 


Steve Shannon, P.E.


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## pdentrem (Dec 13, 2015)

Steve Shannon said:


> The pinion, on the right, is about 7/8 inch thick. The gear on the left is 3/4 in. thick.
> Let me know when I start to irritate you.
> Does yours have a zerk?
> Also, can you slide the back gears left and right? I don't see a set screw and mine definitely slide, about 1/8 inch or so.
> ...



The gears measure the same on mine. I will get dimensions Monday on the Jet at work.
Pierre


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## Steve Shannon (Dec 13, 2015)

What brand/model is your clone? Is the back gears part the same Module Pitch 2, with 22 and 52 teeth?
Having more part availability would be good. With enough information I might be able to put a spreadsheet together showing which models share which parts. 
Thanks!


Steve Shannon, P.E.


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## derf (Dec 13, 2015)

Mine is a Jet BDB 1340 that was purchased new in 2000. The only difference I see is that mine has a longer bed and is a different color. I would assume that since the swing is the same, the headstock would be the same. My manual shows that the gear has 52T/22T, and the part #04109A.


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## Steve Shannon (Dec 13, 2015)

The shaft and back gears came out easily today. On the 22 tooth end the bronze bushing is obviously worn or machined off center. 
	

		
			
		

		
	





The headstock casting looks like it's in good condition, so far. 




Steve Shannon, P.E.


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## Steve Shannon (Dec 13, 2015)

derf said:


> Mine is a Jet BDB 1340 that was purchased new in 2000. The only difference I see is that mine has a longer bed and is a different color. I would assume that since the swing is the same, the headstock would be the same. My manual shows that the gear has 52T/22T, and the part #04109A.


If this project works out okay, I'll see about painting mine. 
Two weeks ago I didn't think mine could be salvaged. Now I'm optimistic. 
The bore in the back gears is just over 13/16". The helical angle looks like it's about 15 degrees, but I don't have a good way to measure it. 
What would those of you who have rebuilt machines do next to rebuild the back gears?  I'm going to be too busy to do anything until late January, but apparently I like obsessing over things like this. 


Steve Shannon, P.E.


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## GarageGuy (Dec 13, 2015)

I had a Logan lathe that had several teeth knocked out of the bull gear.  A replacement gear was available, but it was $500.  I pre-heated the gear, MIG welded the area where the teeth were missing, and then slowly cooled the part in front of a quartz heater (the kind used to cure powder coat, 450+ degrees) over a period of several hours.  No cracks!  Then I used a high speed cutoff tool to cut slots where the teeth should be, and hand filed tooth profiles back into it.  It worked like a charm, and the machine is still working fine to this day.  Just fuel for those times when folks say "it can't be done".  It can!

It looks like you are making excellent progress.  Great work!

GG


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## Steve Shannon (Dec 13, 2015)

Thanks, GG,
I'm supposed to be finishing the shop though, not succumbing to the allure of a wounded machine. 


Steve Shannon, P.E.


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## GarageGuy (Dec 13, 2015)

Yep, first things first.  Having a new shop with lots of space to work will make the lathe project easier later on.  I would jump through some pretty crazy hoops to get a new shop, but it's not gonna happen.  The garage is what it is  

GG


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## therickster (Dec 13, 2015)

This is mine it's a 1989 you have some extras that I didn't get with my lathe. With what you have taken apart so far how hard would it be to change out the belts? I have 
Been thinking about using the belts that come apart in pieces . Keep up the good work on your project.




	

		
			
		

		
	
 [/GALLERY]


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## Steve Shannon (Dec 13, 2015)

Nice! Do you have the threaded spindle nose too?  I sort of wish I had the optional D1-4 interface. 
If you have no problems with your back gears or spindle then I would choose the link belt. If you decide to change the belts then you may want to change the bearings at the same time. 


Steve Shannon, P.E.


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## therickster (Dec 13, 2015)

[Yes it has the 2 1/4" threaded spindle same as yours .  Everything works so I'm not to excited about taking it all apart. I got this lathe from a older guy 2 years ago . He purchased it from a school. I'm happy with it. I'm a beginner and have a lot to learn.I think I will pick up the link belts just in case I need them some day. I have the manual if you need any info on your lathe. I think you will be happy with your lathe when you get it up and running. Craig's list can be a wonderful thing!]

View attachment 116552


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## Steve Shannon (Dec 13, 2015)

When I click on the attachment I receive an error. It may be security on my end.
Steve


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## pdentrem (Dec 14, 2015)

OK here is a drawing of the backgear assembly in the BDB-1340A at work. The worst that could happen is that you will have to bore out the new gears off the shaft and make a new shaft to fit them to your machine. The dimensions are approximate as I did not remove the assembly naturally.
Pierre


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## Steve Shannon (Dec 14, 2015)

Thank you for that, Pierre. I really appreciate your help. 


Steve Shannon, P.E.


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## Steve Shannon (Dec 14, 2015)

Pierre,
Thank you for jogging my mind into gear. No pun intended. I can definitely use the BDB-1340 gear part #04109A, which means I can use the bull gear, part #04117A. Worst case, the helical is the wrong angle (helical angle or pitch angle) on the 52 tooth gear on the back gears. I don't expect that, but if it is true then I can replace another gear on the spindle or make a Frankenstein monster using the old and new back gears.
Hmmm...


Steve Shannon, P.E.


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## pdentrem (Dec 14, 2015)

Here is a photo of the Jet gear set. Based upon the photo you posted of your gear set, the gears are cut the same way. The only issue would be the spacing between the two, which I alluded to in the other post.

As for my clone, there is no label anywhere on it. So it is unknown who the maker was.
Pierre


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## Steve Shannon (Dec 14, 2015)

I found my cheap digital calipers. Pierre's drawing matched all the measurements on back gear within a millimeter. 
Thank you, Pierre!


Steve Shannon, P.E.


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## Steve Shannon (Dec 14, 2015)

The OD of the back gear shaft measures 20.56. The bore of the back gear is 20.59. It's a tight fit inserting the shaft; in fact I have to tap it with a plastic mallet, but once it's on it spins freely without feeling loose. How can I be sure the shaft isn't too worn?


Steve Shannon, P.E.


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## pdentrem (Dec 14, 2015)

I would take multiple measurements around and along the shaft. Likely if there was wear it would not be evenly distributed. The .03 mm equals .0012", so that is a nice fit.
Pierre


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## Steve Shannon (Dec 20, 2015)

I think I'll pick up some vee blocks and a dial test indicator as well. No more work on this till after January 21st though. In two days I'll be retired; in four I'll have a new position as a babysitter for our first grandchild!


Steve Shannon, P.E.


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## brino (Dec 20, 2015)

Steve Shannon said:


> I think I'll pick up some vee blocks and a dial test indicator as well.


Those are always useful tools; in fact I consider both necessities for the shop.



Steve Shannon said:


> In two days I'll be retired


Cool congratulations!



Steve Shannon said:


> in four I'll have a new position as a babysitter for our first grandchild!


Even cooler. Not only are you helping out your kids, but you will build a bond with your grandchild that you would never have had otherwise.

Enjoy his/her first Christmas!
-brino


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## Steve Shannon (Dec 20, 2015)

Thanks! 


Steve Shannon, P.E.


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## TomS (Dec 20, 2015)

Steve Shannon said:


> I think I'll pick up some vee blocks and a dial test indicator as well. No more work on this till after January 21st though. In two days I'll be retired; in four I'll have a new position as a babysitter for our first grandchild!
> 
> 
> Steve Shannon, P.E.



Congrats on your retirement.  Did it four years ago and look forward to every day.  We have our four grand daughters visiting this weekend.  It's a mad house but enjoying every minute.  You will come to a point where you look forward to the chaos.

Tom S.


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## Steve Shannon (Dec 20, 2015)

She's four months old this month. Is it too early to give her a Sherline? 

Edit: I checked prices for Sherline; maybe she and I will rebuild a South Bend lathe someday. I just have to convince her dad and mom to set aside space for a workshop. 


Steve Shannon, P.E.


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## Steve Shannon (Jan 25, 2016)

I'm back. Today I removed the countershaft from the headstock. That's necessary to replace the pulley on the end:



Once I got that pulley off I discovered that the keyway on the shaft was damaged also. Here's a picture of it:


My next goal is to remove the spindle. Unfortunately I'm a bit stumped. I know it has to come out toward the bed, but the bearing cover is held not only by four cap screws but by the spindle itself, so somehow I need to clear the OD of the bearing cap. I don't have a bearing puller that will do that. Here's that picture:


More next week. I'm just getting used to retirement. 


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## Steve Shannon (Jan 26, 2016)

I found the tapered roller bearings for the spindle on Amazon today.  From JetTools.com they would have been $100 each.  From Amazon they are $39 and $57 plus shipping. I'll give the local bearing supply house first crack at it, but I wanted to make sure they were available.  They don't even seem to be anything "special": HR30211J and HR30212J.



Also, I think I figured out how to pull the spindle.  I always figured I would just put a piece of protected all-thread through the spindle with a large washer and nut on the outboard end and some way of clearing the bearing cap on the spindle nose end.  I bet I can find a PVC coupling (or short piece of well pipe) that just clears the cap.  I'll post a picture once I get it rigged up, but I won't be able to play with it until Friday.


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## Steve Shannon (Jan 26, 2016)

It appears that the pulley that I removed was not the original.  The bore seemed larger than the original pulley and the key seemed smaller than the slot in the pulley. Either that or when the damage to the key slot happened it reamed out some metal to the bore as well. This pulley had two set screws, which each was locked in place by an additional set screw.  I think I've seen that some of you call that extra a grub screw.  Is that correct?
Anyway, as designed, the pulley is actually held against rotation by the key and it's held on the shaft by a nut and lock nut at the end of the shaft:


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## bcall2043 (Jan 27, 2016)

Steve Shannon said:


> I found the tapered roller bearings for the spindle on Amazon today.  From JetTools.com they would have been $100 each.  From Amazon they are $39 and $57 plus shipping. I'll give the local bearing supply house first crack at it, but I wanted to make sure they were available.  They don't even seem to be anything "special": HR30211J and HR30212J.
> 
> 
> 
> Also, I think I figured out how to pull the spindle.  I always figured I would just put a piece of protected all-thread through the spindle with a large washer and nut on the outboard end and some way of clearing the bearing cap on the spindle nose end.  I bet I can find a PVC coupling (or short piece of well pipe) that just clears the cap.  I'll post a picture once I get it rigged up, but I won't be able to play with it until Friday.



I have been following your thread with interest as I too have adopted a older Jet lathe (actually 2 lathes) with issues.

You probably already know this but it might be helpful for some of our fellow Hobby Machinist to learn a little about bearing precision.

All bearings that will fit into our machines are not equal. Some are more accurate than others. The bearing manufacturers produce the bearings as best they can and then select and grade them. This quality and grading process adds cost. The end user (machine manufacturers or hobbyist) specify what quality bearing they need, want, or willing to pay for. In today’s world the good manufacturers like the one I have selected (Timken) to post a link to make really good accurate products. We have no idea what quality bearing was originally supplied from the original manufacturer of our hobby machines, what is supplied by Jet Tools, or the others you contacted for prices. I would hope that Jet Tools would supply the appropriate quality level for their application but who knows in today’s global market place.

For the learning pleasure of our members I have attached to link below that will supply a little information about bearing precision:

http://www.timken.com/en-US/products/Documents/Super-Precision-Bearings-for-Machine-Tool-Applications-Catalog.pdf

The picture below shows how this bearing manufacturer “may” label their precision products.


The picture gives some other page numbers for the TIR readings for those interested. The web link above also includes links to other publications about installing and service this type of bears.

Good luck with your project.

Benny
The Orphanage Never Closes


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## Steve Shannon (Jan 27, 2016)

Benny,
I appreciate your post. I knew some of that, but no real details. The photo I posted is of one of the bearings that is currently in the lathe. I'm traveling today and only following this on my phone (and tablet when in the hotel), so I haven't looked at the additional info you have provided. Wouldn't the part number marked on the bearing reflect the precision spec of the bearing?


Sent from my iPhone using Tapatalk


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## Steve Shannon (Jan 27, 2016)

Now I have glanced through the first few pages of the 258 in the Timken document you linked. The NSK bearing number referenced by Jet, which matches the bearing I photographed, does not attempt to reflect as many details. I'll look at the NSK site to see if I can learn more. Thanks again for the info. If you know an easier way to cross reference the NSK bearing to a superior Timken bearing I would be interested in learning it.


Sent from my iPad using Tapatalk


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## Steve Shannon (Jan 27, 2016)

I see that the number marked is a standard part number which can be used to view a similar part in another company's catalog. I'll check this out. 


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## Steve Shannon (Jan 27, 2016)

Well, I'm dumber than before (or I am aware of more of my ignorance).
Motion Industries has a web page that lists my bearing along with bearings they call "substitutes", but the max RPM and load data differ among the original and substitutes. For now, I think I'll just stay with the same part/manufacturer's bearings that I find in the headstock (which are probably good enough) instead of trying to second guess myself and the manufacturer.  "Best is the enemy of good enough."


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## bcall2043 (Jan 27, 2016)

Steve Shannon said:


> Benny,
> I appreciate your post. I knew some of that, but no real details. The photo I posted is of one of the bearings that is currently in the lathe. ......................... Wouldn't the part number marked on the bearing reflect the precision spec of the bearing?



Steve,
Sorry, I not sure about the labeling methods used by the different manufacturers to indicate bearing precision. The company that I retired from used a number of “Special” bearings in the machines they manufactured. As I recall Timken used a grading and selection process for the special roller bearings we received. Our engineers specified the bearing cone, cup, rollers and bearing class. Timken selected the best components during the manufacturing cycle, inspected and (banded) them together as a special assembly. That method seems to be indicated as still used in the link provided. We had to order them way in advance of requirements because of their manufacturing procedures and the quantities we used. I also recall that we used a “special” sealed ball bearing by a different manufacturer where only thing special was the lubricating grease required for very high operating speeds in our application. If I recall correctly these bearings once unpackaged and installed had no indication of their special features. This often resulted in problems when customer maintenance personnel purchased replacements from their local suppliers because they were cheaper. They did not always get the accuracy or bearing life because they had lost the “special features” of the bearings.

In my collection of "hobby hoarded stuff", I have a New Departure branded machine tool bearing with the box labeled “Gold Series”. I have not needed it or opened the box to see if the bearing itself is marked. Maybe I will if I can find it.



Steve Shannon said:


> Motion Industries has a web page that lists my bearing along with bearings they call "substitutes", but the max RPM and load data differ among the original and substitutes. For now, I think I'll just stay with the same part/manufacturer's bearings that I find in the headstock (which are probably good enough) instead of trying to second guess myself and the manufacturer.  "Best is the enemy of good enough."



Steve,
I am sure that you are right that the off-the-shelf bearings will probably be okay if they provide the accuracy “wanted” by us hobbyist. I have been researching for related inspection information because the machine I need to get operational has seen some abuse. I have seen a little information about spindle TIR but not a lot. Most of the manuals I have looked at for the import machines are lacking in definitive information or full of errors.

Benny
The Orphanage Never Closes


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## Steve Shannon (Jan 27, 2016)

It looks to me like the NSK bearings and the substitutes all use numbers that are considered an ISO numbering standard. So a bearing marked 30211 from Timken, NSK, etc, all have the same bore, OD, and width. However, there are different prefixes used be the manufacturers that signify additional specs, such as the HR prefix and J suffix that appears on my bearing. J means it's capable of withstanding a higher dynamic load I believe. A suffix of C is not capable of handling high RPMs (so We wouldn't use that). 
I am interested in learning what runout to expect from the bearings mentioned by Jet. I believe my original manual actually has a list of brand name and part number for the bearings used in my lathe. Once I get home I'll dig it out and post the info. Thank you again; I find this to be a fascinating subject in an area that I never dealt with in my career as an engineer. 


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## Steve Shannon (Jan 29, 2016)

Today I removed the headstock from the lathe.   It was easy, four screws and big grunt to lift it.  I didn't completely remove it; I just moved it aside while I removed the shank of the cap screw that a previous owner had broken.  I know I'll have to readjust it, but I would have wanted to remove it anyway to clean it all up. 

Also, I tried to get the spindle to budge.  I tried tapping it with a dead-blow hammer, like a couple of people on YouTube, but no luck. I didn't think I should pound it too hard, so, I'll get a large piece of all-thread and try to gently, but firmly, persuade it like I discussed earlier.  While I was studying the spindle, I was once again bothered by the fact that the pulleys and gear on the spindle (except for the bullgear) all slide along the spindle, roughly 3/8 or more inches. They have to be able to spin freely when the lathe is in backgear, but they should not slide axially on the spindle. The axial play is enough to allow the pulley next to the bullgear to disengage from the bullgear when the locking pin should keep them turning together.  I don't see any way to prevent the axial movement the way my spindle is now.  There is a spacer with a set screw at the left end of the spindle, just inside the left bearing. It's about 3/8 or so wide. Looking at it I wondered if there should be another spacer to take up the additional play.  Then I looked at the diagram for the BDB-1340 again.  The spacer in that diagram (which appears as part #35 here) looks like it would be much wider than the spacer on mine:



Could one of you with a BDB-1340, or better yet with a 13xxPBD measure, or even estimate, the axial length of that spacer? If it's nearly 5/8 or 3/4 inch (or 18 mm) or longer, then my mystery is solved and I will know that the spacer on mine is simply the wrong spacer.
Thanks!
Steve


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## Steve Shannon (Jan 30, 2016)

Steve Shannon said:


> Today I removed the headstock from the lathe.   It was easy, four screws and big grunt to lift it.  I didn't completely remove it; I just moved it aside while I removed the shank of the cap screw that a previous owner had broken.  I know I'll have to readjust it, but I would have wanted to remove it anyway to clean it all up.
> 
> Also, I tried to get the spindle to budge.  I tried tapping it with a dead-blow hammer, like a couple of people on YouTube, but no luck. I didn't think I should pound it too hard, so, I'll get a large piece of all-thread and try to gently, but firmly, persuade it like I discussed earlier.  While I was studying the spindle, I was once again bothered by the fact that the pulleys and gear on the spindle (except for the bullgear) all slide along the spindle, roughly 3/8 or more inches. They have to be able to spin freely when the lathe is in backgear, but they should not slide axially on the spindle. The axial play is enough to allow the pulley next to the bullgear to disengage from the bullgear when the locking pin should keep them turning together.  I don't see any way to prevent the axial movement the way my spindle is now.  There is a spacer with a set screw at the left end of the spindle, just inside the left bearing. It's about 3/8 or so wide. Looking at it I wondered if there should be another spacer to take up the additional play.  Then I looked at the diagram for the BDB-1340 again.  The spacer in that diagram (which appears as part #35 here) looks like it would be much wider than the spacer on mine.
> 
> ...


I was wrong. It was tucked in under the rubber oil seal of the outboard bearing. I'll have to figure that out. I don't think that it should have been. It really is wider than I expected. 





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## brino (Jan 30, 2016)

hmmmm........a mystery, but I am following along.......
-brino


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## pdentrem (Jan 30, 2016)

Yes it goes into the seal. It is actually a bad design as it can allow lube oil to leak out, all be it slowly as the oil level at rest is below that level. Still makes a mess though.
Pierre


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## Steve Shannon (Jan 30, 2016)

Okay, Pierre, after holding it against the seal I have to agree, but I suspect it went too far past the edge. The spacer has one edge that has a larger chamfer. Should that edge be on the seal side or against the gear?


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## pdentrem (Jan 30, 2016)

I had the spindle out on the Jet lathe, at work, a few years ago to replace the seals and check the bearings, so this is just by memory and may not be 100% correct.

In looking at my assembly page in the printed parts manual, to refresh my memory, that came with the lathe, #35 is the spacer you have posted the photo of. The chamfer is the side that enters the seal. It is also the side the o-ring #37 will seat against. It is to stop that pesky leak! The oil seal is 70mm ID to fit the OD of the spacer while the o-ring is 60mm to fit the shaft that the spacer rides on.

As for that HUGE amount of play that you have, #43 locking nuts push against the following items in order - #42 50T gear, #38 spacer, #6 outer bearing. The next 2 parts #37 o-ring and #35 spacer are held in place via that set screw to the spindle. They are not involved in the bearing preload that is next. The spacer #35 is actually there to fix the location of the #34 44T gear and the 3 groove pulley #30. They just sit on the spindle and run on the bearing #32. So that spacer sets their furthest left they are allowed to move and the #29 74T bull gear sets the right side. There is a shoulder that the bearing #6 is seated against on the inside of the casting so that it can not go in any further and by adjusting the #43 locking nuts you tighten them to reduce the play and set the bearing preload of the spindle itself.

I think that the above is correct but this was I believe atleast 5 years ago or more.

Pierre


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## Steve Shannon (Jan 31, 2016)

That's exactly what I hoped. So whoever took the spindle out and replaced the belt before me did not put that spacer up against gear #34. That's also why the spacer was so far under the seal.  Also, there was no O-ring on my spindle. 
Thank you!

I've got a question about removing the cones for the bearings also. Both are seated tightly in the headstock still. The bearings look like they're in great shape; no scuffing, scoring, or spalling that I can see. Do I leave then be and just clean the bearings and reassemble them, or remove the cones from the headstock first. My original thought was that since I've done this much I should put in new bearings, but I'm unsure that I can get the cones out of their seats. 


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## pdentrem (Jan 31, 2016)

For our proposes I would leave them in and just do a clean and reassemble.

 To remove the outer cones, 2 ways. Hammer and brass drift with lots of tap tap tap all around to slowly work them out and install new ones in.  The second way is to make a cup or plate to be able to use a gear puller. Hammer and drift is the preferred way by most people. Obviously a good flush of the old lube to remove any debris in the casting is of benefit to the life of the bearings. I remember when we got the Jet new, I flushed out the lube first before even spinning it up and then did it another 3 times to get clean. There were still some marks on the races when I opened it up but not enough to replace at the time. The lathe is now 15 years old and still running on the original bearings. I change the oil from time to time. It only runs a few hundred hours a year as most work is done on CNC and Wire EDM in our shop. I have not opened up my clone at home as of yet, and it is much older than the Jet.
Pierre


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## Steve Shannon (Jan 31, 2016)

Thank you again for your help. I described it wrong. The cone for the inboard end of the spindle stayed on the spindle. The cup for the outboard end stayed in the headstock. I think I will do as you say, just reassemble with a new bullgear and belt. If I discover later the need to replace the bearings I know how. 


Steve Shannon, P.E.


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## Steve Shannon (Feb 4, 2016)

How do those of you who repaint your machines remove the drive pins without marring the metal plates they hold?


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## Steve Shannon (Feb 6, 2016)

Never mind.  I searched for drive screws using the search function for the site, but came up with a lot of hits that were not helpful.  Today, I used Google and found this link, pointing back to this site, the perfect answer to my question.
http://www.hobby-machinist.com/threads/removing-rivets-and-drive-screws-from-nameplates.869/


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## Steve Shannon (Feb 8, 2016)

I might be stupid or I might be hard headed; I guess we'll all know soon! I'm convinced that the headstock gears and pulleys in the Taiwan built Jet 1336 PBD that I have are so nearly close enough to the mainland China built BDB-1340 that I can use the BDB parts to replace the broken bull gear and backgear in my PBD. PDentrum was kind enough to measure his backgear (as well as possible without taking his work lathe apart) and found it to be very close. I was hoping that the Jet parts store would let me  return them if I'm wrong. Turns out they won't and they told my local Jet Service Center that the parts won't work. I ordered them anyway. I think I can make them work. 
Wish me luck!


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## pdentrem (Feb 8, 2016)

The lathe is a machine that can replicate itself! You will succeed, one way or the other.
Pierre


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## Steve Shannon (Feb 8, 2016)

Thanks for all your help and encouragement, Pierre! 


 Steve Shannon, P.E.


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## Steve Shannon (Feb 11, 2016)

Well, I was in the big city of Billings, Montana today. They have a Motion Industries location, so I stopped in and asked about high precision bearings to replace the NSK bearings that were in this. The Customer Service Representative really spent some time with me. She called both Timken and SKF      while I was there to see if either one had high precision bearings in the ISO sizes 30211 and 30212.  Unfortunately neither did. SKF said that they could do some if I wanted to purchase a large quantity. Because I don't even know if I could afford one set of "super precision" bearings I surely didn't want a quantity of them. I ended up telling MI to order the Timken 30212m and that I would take the 30211m they had in stock. I'll pick them up in March when I'm there again. 


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## Steve Shannon (Feb 16, 2016)

pdentrem said:


> The lathe is a machine that can replicate itself! You will succeed, one way or the other.
> Pierre


But only if it operates! 


 Steve Shannon, P.E.


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## Steve Shannon (Feb 17, 2016)

Yesterday I went to visit the widower husband of a lady I worked with for the past ten years.  She passed away just a week before I retired.  He asked me on Sunday night if I would like to go on a "fun run" with him, which really does not involve my running (much to my relief) but rather involves 4 1/2 hours of running four wheelers or UTVs through deep snow, much like a roller coaster that left its track!
It was a lot of fun and I enjoyed myself.  However, while visiting with him in his shop before we went on this Fun Run, we were talking about tools and I was admiring his neat-as-a-pin shop, when I mentioned that I used to have a Unimat. He got a funny look on his face and beckoned me over to a set of shelves.  From it he pulled a familiar looking box.  In it was an old SL (DB-200) Unimat.  Then, he gave it to me, just like that.  I'm 60 years old, but when I opened the box and looked at the various parts and accessories I had that same old thrill I had forty some years ago when I ordered and received my original Unimat.  I'm stoked to have this.  I'll post a few pix tomorrow. 


 Steve Shannon, P.E.


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## bcall2043 (Feb 17, 2016)

Steve,

Glad your friend gave the lathe to someone who appreciates what he has received. I got my first lathe about 40+ years ago and in a moment of weakness I traded it to fellow forum member a few years ago. I have regretted it since. 

This hobby is a sickness and we grow sicker with age. I only have four lathes right now and only one of them is operational. I need to clean house.

Don't let this one get away from you.

Benny


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## tertiaryjim (Feb 17, 2016)

Steve
I have the exact lathe as you. The tag says Made in Taiwan.
Got tired of all the play,slop,and vibration and started learning to scrape.
Been doing it " on the cheap " but it's still expensive and has been greatly time consuming.
The learning experience has often been frustrating with a lot of ,O Crap, moments.
Still there has been the satisfaction of seeing greatly improved finishes, faster machine cycles, rigidity is greatly increased so I can now zoom right through parting operations that it couldn't handle before and
I'm learning a new skill.
I also recently tried to get new bearings and found the same result as you. 
Considering the cost of  the "P" or grade 5 bearings you might think about just installing truck bearings. Since the main load bearing isn't available and that one expensive bearing on the OB end won't do much
by it's self.


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## Steve Shannon (Feb 17, 2016)

Thanks, tertiaryjim. Both bearings were available and arrive at the dealer today. I'm going back to Billings in two weeks. I'll pick them up then. Specs say that both Timken bearings have a runout somewhere about 25 microns, if I remember correctly. I think that anything I'm likely to build can be done with that accuracy. 
What brand/number of main bearing did yours have?


 Steve Shannon, P.E.


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## tertiaryjim (Feb 18, 2016)

Bearings are HR  30211J and 30212J
Just went through all 4 pages of this thread and found where I might have helped early on.
If you still have any questions I will gladly try to answer them.


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## Steve Shannon (Feb 18, 2016)

tertiaryjim said:


> Bearings are HR  30211J and 30212J
> Just went through all 4 pages of this thread and found where I might have helped early on.
> If you still have any questions I will gladly try to answer them.


That's exactly what mine were. I don't know if it's an upgrade or not, but I went with the Timken.  I might even get one of the Timken decals and put on this. 


 Steve Shannon, P.E.


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## tertiaryjim (Feb 18, 2016)

Just remembered that the spindle threads are metric.
Will check them when I next change chucks but memory says they are very close to 8 tpi
Don't have a metric pitch gauge that goes over 2mm but could measure them with calipers.
Think it's a 3mm pitch.


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## Steve Shannon (Feb 18, 2016)

My manual says 2 1/4 x 8 tpi. 


 Steve Shannon, P.E.


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## tertiaryjim (Feb 18, 2016)

After cutting a 2 1/4 -8tpi thread, for a spider, that didn't fit I took a good look with a 8tpi thread gauge.
Didn't line up. Just a small difference.
This is why I think they just used what was close. Have seen other examples of this in the industry from china.
Have cut hundreds of threads of several styles as well as specials to match weird china stuff over the years.
Ya,these were made in Taiwan but are low end machines with poor fit and finish. 
Before I try again I'll be checking everything out as well as the change gears and measuring the pitch closely.
A six jaw chuck, Bison, that I purchased with a 8 tpi backplate fit, but the threads are very loose and it hasn't more than 
4 or 5 mating threads.


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## Steve Shannon (Feb 18, 2016)

My Polish chuck fits nice and tight. I'm starting to think you and I have different build quality. Maybe Jet was having a bad day when yours was built. Mine does not have poor fit or finish that I have detected. One of the primary reasons I bought this was because of the good things people said about the Jet 1336 PBD. It's not a Hardinge, Monarch, or even a South Bend, but it is better than many of the lesser imports. The worst thing about mine is that it was improperly maintained. That's what I intend to rectify. 


 Steve Shannon, P.E.


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## Steve Shannon (Feb 18, 2016)

Your post does remind me to add thread gauges to my Enco order today 


 Steve Shannon, P.E.


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## pdentrem (Feb 18, 2016)

The backing plate will be loose on the threads. The chuck actually will seat firmly against the spindle shoulder so the thread fit is not super critical. I made 2 backing plates for my threaded spindle in 2013 and the 8 tpi setting was accurate on my lathe. I did post a topic on the making of the backing plates.
Pierre


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## tertiaryjim (Feb 21, 2016)

Pulled the chuck off and checked the spindle with a 8tpi thread gauge.
The OB thread is very fat or wide in the OB direction. Just a bit more than one thread or rotation. Will work on that.
Something I had forgotten is it looks as though I need a 23 tooth gear to cut 8tpi.
Had noticed it after failing to get a proper thread and looking for the reason. Since I don't have one, something more to make, I set all such work aside and forgot what I had found at the time.
Now I plan to make the parts and a cutter to get my power hacksaw running so I can cut parts to make a power lap to grind the carbide scrapers and make indicator jigs so I can scrape my 
mill-drill and shaper so I can make more parts to........ You get the idea.
The first part I scraped was the lathe cross-slide. Pulled it off and put it on a surface plate. It rocked on two corners. The rest of the machine was no better.
Work done has made great improvements but there's more to be done. When complete, I think it will be a accurate and capable machine.


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## Steve Shannon (Feb 24, 2016)

Steve Shannon said:


> My manual says 2 1/4 x 8 tpi.
> 
> 
> Steve Shannon, P.E.


I received the thread gauges and the spindle thread measures 8 TPI. 



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## Steve Shannon (Feb 24, 2016)

Steve Shannon said:


> I might be stupid or I might be hard headed; I guess we'll all know soon! I'm convinced that the headstock gears and pulleys in the Taiwan built Jet 1336 PBD that I have are so nearly close enough to the mainland China built BDB-1340 that I can use the BDB parts to replace the broken bull gear and backgear in my PBD. PDentrum was kind enough to measure his backgear (as well as possible without taking his work lathe apart) and found it to be very close. I was hoping that the Jet parts store would let me  return them if I'm wrong. Turns out they won't and they told my local Jet Service Center that the parts won't work. I ordered them anyway. I think I can make them work.
> Wish me luck!



Here is the new backgear, next to the original, which is on the right:


The differences are:
The new gear is cast iron. The old gear is some kind of steel. 
The new gear does not have bronze bushings.
The new gear has a bore which is about 50 thousandths larger diameter than the old gear. I don't think that's large enough for a bushing without boring it out first. Or I could sleeve the shaft the backgear runs on to increase its O.D. 
Other than those things I believe the gear will work just fine. 
Now I'm eager to hear other's opinions on how to make this work. The options I can visualize include sleeving the old backgear shaft, boring and bushing the new backgear, or turning a new backgear shaft (which is eccentric). 



 Steve Shannon


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## tertiaryjim (Feb 24, 2016)

8tpi is correct. I was fooled because the outboard thread is thick and a gauge wouldn't sit on it properly. Can't imagine how they machined it like that but there's no indication of distortion.
I used a diamond file and worked the worst of it down. May try to single point cut it at some point but will need to make a gear first.

Steve
If there is no damage to the old gear I would just put in new bushings. Because the eccentric shaft must be worn ? ? I would make a new one. Don't know what material the manufacture 
used but some tough material like 4140 pre-hard would be good and would allow a much better surface finish than lower grade steels.
Don't need a mirror finish as there must be a bit of drag to help spin the lube around.
Getting the eccentrics on each end of the shaft to line up might be difficult.
If the gears have wear due to running with bad clearance then the mating gears will also be worn.
I doubt there is any real gear wear and they just didn't lube the shaft. Will need to go back through your thread to see what wear you found in the geared sleeve that 
goes on the spindle. Should have at least 1.5 thou or because it's lubed with light grease 2 thou might be better. Its low speed anyway.
Cast iron has better dampening characteristics but I doubt that would be much  of a consideration.


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## Steve Shannon (Feb 24, 2016)

I agree, not much wear on the old gear, but one tooth on the backgear and one tooth on the bullgear were broken off when I got the lathe.  I might have been able to have someone braze in new teeth, but because they are helical I decided I wanted to completely replace them, keeping the original gap tooth gears as spares, just in case. The eccentric shaft may be slightly worn, but not enough to matter (I think??)
Making a new shaft appeals to me in a way, but I'm going to have to figure out how to set it up and center drill it to turn between two precisely spaced axes. 
Thanks for your help! I'm feeling my way through this...


 Steve Shannon, P.E.


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## Steve Shannon (Feb 24, 2016)

Here's the eccentric shaft:




 Steve Shannon


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## tertiaryjim (Feb 24, 2016)

For that size shaft the bronze bushings should have a minimum of 1 1/4 thou. clearance.
I use a light grease for lube which has worked fine. With grease the clearance can be a bit more 1.5 to  even 2 thou.
Since your going to install new bushings it wouldn't hurt to make certain the shaft is true and round.
Shaft looks fine in the picture but your eyes and mic will tell the truth.
You might consider, if the shaft needs it, to turn a few thousanths off the old shaft to clean it up. Then machine the bushings to fit.
Can't remove much but you have a little wiggle room.
The bushings need a interference fit in the back gear but just 2 or 3 tenths should be fine. The bushing bore will shrink when pressed together so it should be oversized the same amount.
If your a few tenths over or under your target clearance it's just fine as long as you have at least 1 1/4 to 1 1/2 thou clearance.


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## Steve Shannon (Feb 27, 2016)

Actually, I haven't quite made the decision to install bushings yet, due to the difficulty (for me anyway) of boring the new gears sufficiently to install bushings.  I'm considering having the cast iron bore of the new backgear set ride directly on a slightly larger eccentric shaft.  The OD of the eccentric shaft is only .05 smaller than the ID of the new backgears, which is smaller than the thinnest walled bushing.  If I had a way to bore the backgears out I would definitely install bushings.  I've even looked at Igus plastic bushings which can have a much thinner wall, thinking I might not have to bore out the backgear. 
I will be using oil to lube these.
Once I get the spindle and bearings back into the headstock then I'll be able to turn the eccentric shaft and ensure it's round. It's off by a few thousandths right now and the smaller portion of the shaft is slightly mushroomed. 


 Steve Shannon, P.E. 
Edited to correct relationship between new backgear bore ID and old shaft OD. Shaft is smaller, not larger, than gear bore.


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## Dan Coleman (Nov 20, 2018)

I'd like to revive this thread and add a little and maybe learn a little about the differences in the Jet 1330 machines.  Mine is a BD-1336T.  The pdf manual I have says BD-1325R, BD-1336R , and BD-1340R.  I also have a hard copy manual for 13BH series (BD-1325R BD-1336T, and BD-1340T).  There is not much difference.  Here is what it looks like.  I'll have to search for coo and serial number.

I have all of the extra gears and such that should have come in the red tool box.  Most of my extra stuff was never unwrapped for the paper and cosmoline.

Hopefully we can help each other with the iinfo exc
	

		
			
		

		
	



	

		
			
		

		
	
hange.


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## Jerry Stephenson (Feb 27, 2019)

Hello,
I'd also like to revive this thread.  I have a Jet that looks an awful lot like the one above.  However, I think it is a bit older.  It has a open legged stand instead of the cabinet stand. The previous owner made a tube steel stand that it is no now.  I'm cleaning it up and restoring it and really need a manual.

The nameplate says mine is a 1336-PBD from 1988.  It has a 2 1/4" - 8 threaded spindle.  I am pulling the spindle to put new oil seals and probably bearings while I've got it apart.  I would like a manual or any comments from anyone who has ever pulled the spindle on one of these.

I assume I can just loosen up all the things attached to the spindle with setscrews (pullys and gears) and make a threaded rod jack and pull the spindle out. 

Once I have it out, it would be great to switch to a D1-4 spindle...not sure how expensive that would be or if it is available...I might consider making one. 

Near as I can tell by direct measurement the outboard outside oil seal is 62mm x 85mm x 10mm.  I assume they are all 4 the same but would love a manual to confirm. 

Please let me know if you have a manual/parts list. thanks, Jerry


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## brino (Feb 27, 2019)

Another thread here:
http://www.chaski.org/homemachinist/viewtopic.php?t=82841

suggest this lathe is very similar to the Grizzly G1003.
If so, two manuals can be found here: 
https://www.grizzly.com/products/LATHE-12-X-37-METAL/G1003
under the documents tab.

Might be worth a look.
Good luck!
-brino


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## Jerry Stephenson (Feb 28, 2019)

Update.  I have obtained a good digital copy of the original Jet manual for this lathe.  Anybody who wants a copy please send me a private message with your email address.  

.
	

		
			
		

		
	




Here is a snip of the spindle drawing.  I'm planning to jack the spindle out with a threaded rod jack.  I have loosened 3 set screws, 2 on the pully and one on the spacer to the left of the drawing.  I think that is it.  Once I jack it over about an inch, I'll slide the pully over and take out the key that is under the large helical gear.  

this will leave the inboard tapered roller bearing in the headstock under the bearing cover.  I'll be jacking against the bearing cover but it is aluminum and I'm a bit concerned about damaging it.  Not too hard to make a new one if I have to.  The other option would be to loosen the capscrews and jack the head cover off and the bearing might come out on the spindle.  Then I would still have to press it off.  

I'd be very happy to hear from someone who has done this job before.  If it rains this weekend, and it is forecast to, I plan to do this job.

--Jerry


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## Jerry Stephenson (Mar 24, 2019)

Took the spindle out today.  Ordering new bearings and oil seals.  

Anybody have a recommended bearing brand/part number /supplier?  the bearings are both tapered roller, 30211A and 30212A.  Lots of inexpensive bearings available, and a few more expensive bearings available,  but I don't know what is really appropriate for such an older lathe.  Not that easy to take apart so I want to get good quality bearings the first time.  Not as worried about cost as quality.

--Jerry


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