Cross over kabota for compression test

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I want to post this picture for two reasons, I did it and all you fellow helped me get to the point where it was possible, starting back early when Rick and other helped me through the fear of threading, you all said it was easy but I could not see that at the time but practice did bring me to the point that I am able to dive in now, still would like to get the picking up threads but that will come, my thanks to all of you for the help and still learning in my shop and here twice a day, this is a lot better that the news, I can learn here, I wanted to test a Kabota engine on my scag mower, it won't start and thing the compression might be low, went to Harbor Freight and got the compression tester, with all the crossovers there was not one to fit the Kabota engine, what will I do, make one the fellow on the page makes everything, put the short brass in the Mini Lathe, change gears set to 1.5 MM, cut the internal threads till the injector threaded in, put the brass in and turned it till it fit the female, cut the Hex on the mill and drill through with the threads to accept the gauge, don't really know if that is they was it should be done but most of that I learned here the
Kabotacompressionadaptor.jpg
right things that is, so with all that said, thanks to all who share because you do care about helping people along to learn, this is the fruits of your labor, thanks again, Lathe Nut
 
LN,

And the more you do it the easier it gets.

Very well done on taking the plunge.

With regards to which way around you do it. When single point cutting, it doesn't really matter, as you can cut each to match whichever is cut first. I always do the external thread first, purely because it is easier to do and to get spot on size.

When cutting with taps and dies to get a matching pair, you should always cut your internal with the tap first, then gradually bring the external thread down to size using a split die.

There will be no stopping you now.


Bogs
 
Bogs, thanks for those tips, I think that you are right was wondering what I might have to thread next, looks like this is going to be fun but will have to put some think time in it those tips are great, thanks, Lathe Nut
 
Congratulations for taking the threading plunge. For myself, the thought of threading something still seems like some kind of witchcraft or voodoo or something. :hDe:
 
Chris,

I think single point threading is one of the techniques that scares new machinists more than anything else.

But it is the one thing, that when learned, can save you the most money.

Normally for small sizes, I use taps and dies, purely because it is easier to accomplish, but for those large or weird threads, where it would cost you an arm and a leg to buy the taps and dies, then that is the time it comes into it's own.

If your lathe can be set up to give the right pitch for the job you want to do, then you have got the job cracked.

If I was you, I would mount up a bit of brass or ali in your chuck, select a fine pitch with your gearset or gearbox, have the lathe running as slowly as possible then try to cut a thread using the standard methods shown by people on here. It doesn't matter if it is a usable one, just any old thread.

Once you get to see how the lathe works to produce such a thread, it is amazing how quickly you can start to grab it by the scruff of the neck and make perfect threads in all the sizes you want.

Once you have the technique under your belt, it will open up new doors for you to explore.

Bogs
 
It is a skill that can be easily learned once the fear can be overcome.

Learning it is one thing, perfecting it to Lathe Nut's result take a little practice.

THIS is the thread I had originally posted to demystify single point threading.

Suppose someone asked, "how do people walk erect on two feet?".

Well it's kind of a controlled falling forward while moving the feet in an alternating sequense
while maintaining balance to keep from falling on your face, breaking your nose.
We unknowingly tend to swing our arms slightly back and forth to compensate for the body
weight shift involved.

After learning the basics of all of that, most people can graduate to walking and chewing gum
at the same time! ;)

Threading is no more complicated.
It is hand - eye coordination and gaining the confidence to do it.

As I have already said, don't expect results as good as Lathe Nut's on the first attempt.
Try, and practice it. You will get those results sooner than you would expect.

Rick

 
to quote - "don't really know if that is they was it should be done "


If it works it must be right.
 
Nice threading job, Lathe Nut.
Single point threading is one of the most enjoyable things done with a lathe for me, even after
having done it a lot. There's a lot of satisfaction in it.

For the folks who are apprehensive, just try it out when you have nothing else in mind. Use up
some of those scrap bits and cut some threads for standard sized nuts so you'll know when you
have it right, then keep practicing. I think many people do it the first time on something they may
be worried about ruining, and it causes a lot of fretting. Just make a bunch of pieces that you
know can be tossed in the bin without them making problems for some project you're working
on, and the pressure is off.

Dean
 
Thanks fellows, yes the most enjoyable thing is to cut threads on the late, messing around the other night, I decided to cut some double lead threads read a little about, I set the gears for 18 TPI then dropped in the half nut one pass on even and one on odd number then made the nut, he sure runs across that shaft fast, not really sure if all I did was correct but was a threading experience, thanks again for the help and the praise, you all have a great day, Lathe Nut
 

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