# G0602 Cross Slide Modification Need Help.....



## cookj320 (Aug 3, 2016)

I'm doing a Jim Schroeder modification on my cross slide and wondering if anyone out there has done it?
My issue is, in Jim's write up about replacing cross slide lead screw he doesn't give the gear box settings for LH 16.667TPI threads........any insight in this matter would be of great help. Thanks


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## Fabrickator (Aug 4, 2016)

I haven't done that mod but if it calls for left hand threads (LH?), you can't turn left hand threads on a std G0602 w/o another mod to make a reverse tumbler, which he has done looking at the picture.  I did it to mine, but not his version.


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## RJSakowski (Aug 4, 2016)

I looked at the gear chart that I created for the 602 and don't see 16.667 tpi as an available option.  The closest that I see is 16.62 or 16.71 tpi.  It is possible that using the 120/127 gears, you might get closer but not likely to hit the 16.667 exactly.  I am assuming that you are trying to hit 16-2/3 tpi or 50/3 tpi.


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## RJSakowski (Aug 4, 2016)

cookj320 said:


> I'm doing a Jim Schroeder modification on my cross slide and wondering if anyone out there has done it?
> My issue is, in Jim's write up about replacing cross slide lead screw he doesn't give the gear box settings for LH 16.667TPI threads........any insight in this matter would be of great help. Thanks


By using the 120 and 127 gears, I think it is possible to come close enough for all practical purposes.  With a 56 tooth "a" gear and 40 tooth "b" gear and the QCGB set at IIIC, you should get 16.6677 tpi. I need to verify this but will not be able to do so immediately as I have some other work that need to be done today yet.  Possibly this evening or tomorrow.


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## cookj320 (Aug 4, 2016)

Fabrickator said:


> I haven't done that mod but if it calls for left hand threads (LH?), you can't turn left hand threads on a std G0602 w/o another mod to make a reverse tumbler, which he has done looking at the picture.  I did it to mine, but not his version.



Fab, I have done a reverse mod to my G0602 and I believe I'm ready to go forward.......tried[LH threads] twice so far with no luck, keep having multiple Rookie problems..........Like 29.5degrees the other way..........LOL
Any and all help is greatly appreciated. I will keep attempting until I use up my 8' rod. LOL


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## cookj320 (Aug 4, 2016)

RJSakowski said:


> I looked at the gear chart that I created for the 602 and don't see 16.667 tpi as an available option.  The closest that I see is 16.62 or 16.71 tpi.  It is possible that using the 120/127 gears, you might get closer but not likely to hit the 16.667 exactly.  I am assuming that you are trying to hit 16-2/3 tpi or 50/3 tpi.



Here is a link to the exact mod I'm attempting.
http://www.projectsinmetal.com/foru...-cross-slide-more-accurate-and-less-backlash/


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## RJSakowski (Aug 4, 2016)

I found some errors in my tables. It turns out that the recommended gears in the link you posted are your best choice.  The thread will be  16.6663 tpi.  I didn't see the gear box settings but they should be III A.  As always check the pitch with a light cut before threading.  You should have 25 full threads in 1.5".

I approached the metric/English problem a bit differently.  I installed a DRO so I can read the feed in both metric and English.  I use the dial knowing that I am moving less distance than the dial indicates which is good.  

You are undertaking an ambitious project. Good luck with it!


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## Baithog (Aug 5, 2016)

Why don't you just message Jim and ask? I made his threading clutch and he was really helpful. http://www.hobby-machinist.com/members/jimschroeder.21624/


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## cookj320 (Aug 5, 2016)

Baithog said:


> Why don't you just message Jim and ask? I made his threading clutch and he was really helpful. http://www.hobby-machinist.com/members/jimschroeder.21624/



I've done this already no response so far..............


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## Baithog (Aug 5, 2016)

and maybe you wont. I just looked at his profile and he hasn't been around since January. I hope he is OK. He did a lot of high quality write-ups on his projects.


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## cookj320 (Aug 5, 2016)

Ok...................so I made some changes........and SHAZAAM! Perfect LH threads......TPI unknown at this time LOL




I used an old paintball barrel for practice this time. Also I reground my tooling and more accurately set compound slide.


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## cookj320 (Aug 5, 2016)

Baithog said:


> and maybe you wont. I just looked at his profile and he hasn't been around since January. I hope he is OK. He did a lot of high quality write-ups on his projects.



Agreed.............Hoping for the best.......


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## cookj320 (Aug 5, 2016)

RJSakowski said:


> I found some errors in my tables. It turns out that the recommended gears in the link you posted are your best choice.  The thread will be  16.6663 tpi.  I didn't see the gear box settings but they should be III A.  As always check the pitch with a light cut before threading.  You should have 25 full threads in 1.5".
> 
> I approached the metric/English problem a bit differently.  I installed a DRO so I can read the feed in both metric and English.  I use the dial knowing that I am moving less distance than the dial indicates which is good.
> 
> You are undertaking an ambitious project. Good luck with it!



Just verified TPI=16
Thread count in 1.5inches=25
Gear box setting is= III,A
Pretty stoked...........now lets try some 1018........
Thanks so much for help.....


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## cookj320 (Aug 6, 2016)

My first re-attemps in 1018 went poorly.....After some careful adjustments and redneck half-nut operation success!!!













http://[ATTACH=full]187815[/ATTACH]


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## cookj320 (Aug 10, 2016)

After finishing my thread chase I've moved on to the slide bolt and completed the 16.667LH threads last night.









Next I will need to cover threads with something soft and turn down the other side. I've chosen and old 308 case and will cut end off and split down the length.


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## Silverbullet (Aug 10, 2016)

A PIECE of copper pipe may be better it's a little thicker . One slip and the brass case will be cut threads . Lead pipe is the best presses into the threads and grips tite. Just what I've found .


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## cookj320 (Aug 11, 2016)

Brass cases did not work ........piece wouldn't run true, so I will try aluminum or copper. Shell cases are not same thickness all the way down....


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## cookj320 (Aug 14, 2016)

well...I had success using 1/2 inch aluminum tubing from HD that I cut down the middle to cover the threads. To complete lead screw i needed to cut 8mm x 1.25 threads for dial on the other end.
You can see the aluminum tubing i used in one of the pics. Now on to the acetyl nut and boss.....


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## cookj320 (Dec 4, 2016)

I finally completed the lead screw install with no pic's.... thanks for all that helped.  Hunting season and new garage upgrade has kept me really busy. 
will post some pic's tomorrow at work.


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## cookj320 (Dec 4, 2016)

Maybe tonight if I can figure it out.......
Shazaam!


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## cookj320 (Dec 10, 2016)

Here is a pic of my complted lead screw install.....just for posterity.......


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