# Feeds per inch on a Logan 400



## Logan 400 (Sep 13, 2018)

The change gear chart shows the slowest speed is .0046. After studying the ratios I changed a couple of gears and I have it down to about .0028. It still seems too fast for steel. Should I study my tooling or do I need to slow it down some more? Thanks for any input.
Jay


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## stupoty (Sep 13, 2018)

I think my lathe goes down to 0.0025 per rev, gives nice finish, I tend to rough faster, up to about 0.018 per rev.  depends on how rigid the set up is and depth of cut etc. 

Stu


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## Nogoingback (Sep 14, 2018)

I would just give it a try with the steel you normally use and see what you get.


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## Logan 400 (Sep 14, 2018)

I tried it on aluminum and steel. Aluminum was fair but too fast for steel. I ordered another gear so I'll give that a try when it arrives next week.


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## MarkM (Sep 14, 2018)

.0046" is  slow enough for a decent finish cut.  Do you have a radius on your tool.  Check if your tool is on centre accurately.  Take a face cut and make sure it s not leaving a pip or pushing the pip off.


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## Logan 400 (Sep 14, 2018)

I believe I am dead on center but will try a face cut to verify. I tried several tools but I did not try sharpening them. I only tried it out for a few minutes. I have been feeding everything by hand and just started setting up the carriage feed.


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## stupoty (Sep 14, 2018)

Logan 400 said:


> I have been turning everything by hand



That's a good way to get instant feed back on how your tool is set up and if it's sharp


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## Logan 400 (Sep 21, 2018)

Problem solved. It was a number of things. 1) I read the dial indicator wrong. Was actually reading . 0034  2) The tools needed sharpening.  3)The round stock I was using just would not turn smooth.  I installed the new to me gear and sharpened a couple of tools and gave it another try with a different piece of round stock. I like the finish cut I am getting now. The feed is .0024 per rev.


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## Hoyt (Apr 14, 2019)

What were the gears you finally used?


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## rambin (Apr 15, 2019)

i know the best you can get on the old 700 wards is .0046 which is kinda too fast.  but you've cut that in half at .oo24 I would think that would be a nice finish..


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## Logan 400 (Apr 15, 2019)

I will have to look to answer your question. I do remember I also had to buy a small gear. I'm out of town for a couple of days but I'll look when I get home.
Jay


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## Logan 400 (Apr 22, 2019)

Hoyt said:


> What were the gears you finally used?


Sorry it took so long to reply. Here is a couple pictures.


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## rambin (Apr 23, 2019)

hmm my logan 700 chart is different I guess.. lowest I can get is 46 thou per inch.  I thought all the logans used a  pretty similar gear train.


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## Logan 400 (Apr 23, 2019)

I have the same chart but notice the gears I used.


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## rambin (Apr 23, 2019)

ahh your saying you came up with a different array then what logan did....  I guess I just figured they showed every probable option to get the best feeds available


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## wa5cab (Apr 23, 2019)

Rambin,

The slowest feed shown on the chart that you attached is four point six thou per inch, not forty-six.


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## rambin (Apr 25, 2019)

ahh my math aint so good... regardless logan 400 has found a combination to go even slower I will have to see if I have the gearing to do it at some point


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## Hoyt (May 3, 2019)

Logan 400 said:


> Sorry it took so long to reply. Here is a couple pictures.



Thanks!


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