9 x 20 Cross-Slide improvements With Pics :)

Home Model Engine Machinist Forum

Help Support Home Model Engine Machinist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Chazz

Well-Known Member
Joined
May 17, 2010
Messages
132
Reaction score
0
First SORRY I forgot my camera at work, but I will get it tomorrow,I promise.

So for anyone who has never done this, here is a basic list of what I just finished (took about 2 mos, but worth every second two fold, 1 being experience gained and 2, a better lathe! :)

1st weekend - lapped the CS (cross-slide), with 600grit lapping compound, approx 2500 strokes (or until it didn't want to move) :)
2nd weekend - lapped the CS with 800grit, approx 1200 strokes this time (phew)
3rd weekend - lapped the CS with 1000grit, approx 600 strokes and I QUIT! ;D
4th weekend - turned and milled a 4"Dia chunk of 4140 pump shaft (hey it was free) to fabricate the new CS screw support bracket (with 3 screws not the stock 2), bored a thrust bearing pocket, drilled the mounting holes and reamed the center to .510. Drilled and tapped the apron for the 3rd mounting screw.
5th weekend - The guy who drilled\tapped the stock 3 x 3mm Gib screws had too much Saki the night before :big: the holes are both off center and run on a downhill slant from front to back. It's so bad the furthest screw hole actually comes out through the bottom of the CS! So I marked, drilled and tapped (on center) 4 x 5.5mm Gib screws. I didn't bother lapping the Gib strip, just cleaned it up as I have some brass stock coming in next week which is earmarked to replace all my Gib strips. (Mill too) I also milled a larger pocket for the new CS nut.
6th weekend - Removed the lathe bed and brought it to the mill to extend the screw pocket, I also used this opportunity to inspect the apron gears, clean and lube as well as check the half nut.
7th weekend - darn, my 3/4" Dia O1 rod is on back order :( so I grabbed a chunk of 3.75" 4140 and a 4" x 4" x 1/2" chunk of MS and made a big n' heavy holder for my new QCTP.
8th weekend - Started with the handle end of the CS screw and machined up to the shoulder that bears against the support bracket, flipped it around and machined the screw side to .390" and made the 7\16" x 20 TPI LH thread, had to do a bit of cleaning up.
Last weekend - machined, drilled, reamed and tapped the CS nut, made a key for the handle and milled the key-slot on the CS shaft.
This morning - final fit and test, very smooth and solid. Very happy!
And that my newbie friends is just the cross-slide :D BUT WAIT, There's still more!
Cheers,
Chazz
 
At that rate you'll have a completely refurbished lathe in 18.92 years! ;)

Good job. My previous Chinese 7x10 lathe got the lapping treatment. Made a huge difference.

Pics will be nice when you remember your camera!
 
Chazz,

Great and amusing story.... ;D

I must treat my lathe to the same when I get time...... :-\

The thrust bearing mod is a good mod for these lathes as the stock assembly is a bit shaky at best...
 
Ok, so here's some pics, sorry they are 'post' machining.

First, the scew bracket.


I hope you can see where the stock gib-pin protudes from the slide table. :mad:
CS_Table4.jpg

CS_Table2.jpg

CS_Table1.jpg


Here is the lathe bed with bigger pocket and 3rd bolt hole.
Lathe_bed1.jpg

Lathe_bed2.jpg


Here is the stock handle beside the new one, it's amazing how more 'natural' it feels to turn a larger radius wheel! :)
CS_Handle1.jpg


Whilst wating for the O1 Rod, I made a mounting block for my AXA size QCTP, notice in photo 1, the stock holder pales in comparison? Notice in photo 2 how all small tool holders pale by comparison. :)
AXA_Post.jpg

Reference.jpg


FYI, my stock 4 post, bolt, nut, plus 1/2" tool are a little over 1.5 Lbs, the new set-up comes in at a smidge over 9 Lbs! (3.5Kg?ish) ;)

Ahhh...the O1 x 3/4" Drill Rod and 716" x 20 TPI LH Tap & (adjustable) Die finally arrive. :D
CS_Screw2.jpg

CS_Screw1.jpg


Here it is all together,
CS_Finiishish_sorta.jpg


So what's left? ??? And, what's next? Well, Brass is ordered for new gibs, tap ordered to add thumb screw to CS Index Dial.
The new wheel didn't come with a hanlde so I also need to make an 8mm-shouldered screw & handle.
To make a center mark on the CS screw bracket, I decided to try 'Hemmingay Kits' out and ordered their "Graduating Tool" kit (HK1210), plus while I was at it I also ordered (same frieght cost) the "Key Way Slotting Attachment" (HK1230) and the "Retracting Tool Holder" (HK1250) and should arrive next week.
Being a rookie, I make every thing a smidge bigger than I need, so I also have to remove approx .010 from the QCTP base so 1/2" tools are perfectly on center.
:wall: gotta take the lathe bed off again! :wall: And this is why, I also have on order, flat stock and another length of 3/4" PG, O1 Drill Rod to make the 1962 Pop Mech Taper Turning Attachment. So....I have to remove the bed again to mill out the clearence for the TA Cross Slide Connector. BTW Did you know that 9 x 20 in 1962 = 9 x 20 in 2011? :D I checked out the measurements and the only "over engineering" I'm doing, is upping the guide rods from 58" to 34" and the main apron bracket I'm thinkin' 1" thick with a 1/2" milled slot 1/2" deep.......and then there's the tumbler reverse!!! ;)

Thanks for the continued help, insperation and advice,
Chazz




 
Back
Top