Feed rate on my lathe……

[Rik ShawParticipant @rikshaw]

…….to fast.

[Rik ShawParticipant @rikshaw]

On the tailstock gear cover of my imperial W250 V-F it shows the lowest lead screw feed rate as .025 using the illustrated setup of 30 and 63 teeth gears on the top axle – (Z1 & Z2) and 80 & 40 (Z4 & Z3) on the intermediate axle with 75 toothed gear on the lead screw and the feed rate knob set on "C"

My problem is that the feed rate produced with this setup is far to fast for my liking. I have just spent this morning experimenting with a mixture of the nine gears that were supplied by WARCO inclusive of spares as well. These spare gears are 50,55,60 and 70 but I have not been able to get a slower feed rate than .025.

I have no problems with the fixed feed rate on the cross slide which is perfectly usable.

Am I missing something?

Rik

[Christopher Taylor 1Participant @christophertaylor1]

Hi Rik

This might seem a daft reply but you are using the same handle as for the cross slide but in the alternatibve position and not the lower handle? I have an identicle machine and made this mistake.

Chris

[JasonBModerator @jasonb]

Rik,  whats the lead screw tpi. and how many teeth on the fixed spindle gear?

The 280 goes down to 0.07mm or 0.0025" and I don't find it too coarse. Or is that a typo on your part?

The cross feed is not fixed but probably half  or 1/3 the longitudinal, at least it is on the 280.

Put up a picture of the chart and I'll see if I can come up with something slower that will fit the banjo

 

Edited By JasonB on 08/12/2013 14:41:30

Edited By JasonB on 08/12/2013 14:43:02

[Rik ShawParticipant @rikshaw]

Thanks Jason – lead screw is 9TPI and the fixed spindle gear has 40 teeth.

Photo is of the gear arrangement set for the .025 feed as described in my OP.

Rik

Edited By Rik Shaw on 08/12/2013 15:43:24

[JasonBModerator @jasonb]

As I thought you typed 0.025" / rev when you are actually getting 0.0025" which is what my 280 gives and I don't feel the need for anything less.

With the chnage gears you have I can't see you getting any slower.

I would also say you have  an 8tpi leadscrew as the thread cutting chart works with that size lead screw. A being 1:1, b = 2:1, c=1:2 and looks like a 1:3 reduction in the carrage & 1:10 for cross feed.

If you are doing what chris says you will be feeding at 0.008" rather than 0.0025" which could be teh problem. The lower lever is up for X travel and down for Y travel

J

Edited By JasonB on 08/12/2013 15:56:55

Edited By JasonB on 08/12/2013 15:58:42

[Rik ShawParticipant @rikshaw]

Thanks Chris, I'm glad someone else has made the same mistake – I still feel like a tw*t though. I had not realised it was a dual function handle. Just been up the shed and tried it and yes Jason – the saddle feed does look slow enough now. Thanks all for sorting me out.

Rik

[JasonBModerator @jasonb]

Also ignor the C sections being blank on the cross feed you can still use them , the left column ratios will give 0.0007"/rev and teh right 0.001"/rev

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