I would like to kick up my power a bit on my 1937 9" junior lathe. It is in great shape but is a bit to finicky with taking cuts. Don't want to take off no 1/2" or so but more than a scratching every time. Anyone did that? Can not believe it would hurt to be a bit more aggressive.
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9" junior lathe and changing hp from 1/4 to 1/2 hp?
- Thread starter svmade
- Start date
- Replies 15
- Views 1,984
mcload
Hot Rolled
- Joined
- Nov 5, 2007
- Location
- Houston, Texas
Well, my 2 cents, I don't think there would be any problem moving up to a ½ HP motor w/1725 RPM.
They were the standard (I think) for many if not most 9" lathes. I don't know about '39 juniors tho.
I'd go fo it.
PMc
View attachment 285368
They were the standard (I think) for many if not most 9" lathes. I don't know about '39 juniors tho.
I'd go fo it.
PMc
View attachment 285368
I am not sure myself as the real weak link is the adjustable belt that I have already switched to a serpentine. I did tighten the main drive belt to large drive wheel and will see if that helps. Going to test later and this time watch what actually stops turning when it starts to slip.
Attachments
Never mind the question. I did the belt tightening then slowed speed down and can take plenty big passing cuts to suit me. It would slow down in a large cut but did not stop. Sharp tool and the way I go. Just keep hogging cuts just below heavy load on motor. Playing with a lathe is a habit and someday I will need therapy.....
View attachment 285384
View attachment 285384
mcload
Hot Rolled
- Joined
- Nov 5, 2007
- Location
- Houston, Texas
Glad you got the problem solved.
Three thoughts: take your time; slow and steady; don't over-burden the machine. Oil, oil, oil.
A eventually get yourself a can of spray belt dressing. Pulleys and belts can get dirty easily
and will begin to slip. I clean with laq thinner or alcohol.
Your rig looks nice. Four foot bed? Where did you get the benches?
PMc
Three thoughts: take your time; slow and steady; don't over-burden the machine. Oil, oil, oil.
A eventually get yourself a can of spray belt dressing. Pulleys and belts can get dirty easily
and will begin to slip. I clean with laq thinner or alcohol.
Your rig looks nice. Four foot bed? Where did you get the benches?
PMc
tommy1010
Stainless
- Joined
- Apr 21, 2010
- Location
- northeastern Pa, USA
I have a 2 speed pulley that will double your choice of speeds for that lathe. It is the big one. You will have to make or find the little 2 speed pulley for the motor. They are around it is just I don't have any. Let me know via PM.
Good idea on belt cleaning.
Bed is 36" but not sure what you mean on the benches?
Cabinet system I built to fit the lathe ( retired master builder) If you mean the outer wings, I have them to fold down and they come up and click into lock position.
Also I made the cabinet as shallow as possible so I can release the belt tension bar and fold the motor and pulley system to the lathe. I did this so I can fold down the wings, cover lathe and roll it up against the wall for as small of foot print as poss.
Bed is 36" but not sure what you mean on the benches?
Cabinet system I built to fit the lathe ( retired master builder) If you mean the outer wings, I have them to fold down and they come up and click into lock position.
Also I made the cabinet as shallow as possible so I can release the belt tension bar and fold the motor and pulley system to the lathe. I did this so I can fold down the wings, cover lathe and roll it up against the wall for as small of foot print as poss.
According to all the old records of the 9's and 10's had the 1/4 hp as the min hp but not one mention of being able to use larger hp? With good tensions on both belts ( good new serpentine) I am now very happy for what I can do. Just finished making new dials for my cross and compound using the 100 tooth saw blade method I saw on the web. Built my own stamping jig out of oak and all is very well.
iwananew10K
Diamond
- Joined
- Sep 12, 2010
- Location
- moscow,ohio
jrs are pretty stout....i wouldnt hesitate to use 1HP
michiganbuck
Diamond
- Joined
- Jun 28, 2012
- Location
- Mt Clemens, Michigan 48035
svmade,
Nice looking lathe and shop.
Great photos.
I think you might post more often.
Buck
Nice looking lathe and shop.
Great photos.
I think you might post more often.
Buck
mcload
Hot Rolled
- Joined
- Nov 5, 2007
- Location
- Houston, Texas
Well, the benches look great, and I think wheels are great addition. Something about your lathe
reminds me of a 10K. (Shows you what I don't know). Is there paint on the lathe or is it raw cast iron?
If latter, then it must be a job to keep up with rust. Nice job on the dial, by the way.
PMc
View attachment 285491
iwananew10K
Diamond
- Joined
- Sep 12, 2010
- Location
- moscow,ohio
jrs are nearly twice the weight of a 9" workshop or 10k
think of them as a bare bones heavy 10
think of them as a bare bones heavy 10
It has dark gray paint but a lot is warn off. No rust prob as it is in heated shop. its a 1937 9" junior 422YN 3' bed.
mcload
Hot Rolled
- Joined
- Nov 5, 2007
- Location
- Houston, Texas
tommy1010
Stainless
- Joined
- Apr 21, 2010
- Location
- northeastern Pa, USA
Here are some pics of the 2 speed pulley you inquired about. Two of the pics show how it is setup on a 9" South bend.
