# CHUCK fitting issue



## TOOLMASTER (Jul 2, 2013)

i bought a 1 1/2 8 plate for my lathe but it is very loose..i am wondering if i received a 39mm -4...

would they both screw on or would one not fit the other at all?


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## kd4gij (Jul 2, 2013)

A back plate should be a farley loose fit on the spindle so it can register on the shoulder of the spindle.


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## TOOLMASTER (Jul 2, 2013)

It's loose allright . i have 50 wraps of silicone tape and it still moves around as i'm turning ..either the plate is machined too big or something


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## 8ntsane (Jul 2, 2013)

Sounds like you should send that plate back if you just purchased it.
For it to be a slight bit loose as your screwing it on would be normal, but 
What your saying, it way too loose. If it was slightly tight, then it would be different,
and you may be able to fix it. I would return the plate or purchase another in the case you cant return it.


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## kd4gij (Jul 2, 2013)

Mesure the ID of the BP and the od of the spindle. whrer did you get it from.


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## TOOLMASTER (Jul 2, 2013)

I will as soon as they get more in..pita till then...i'm mainly just wanting to know if a 39mm-4 fits on a 1/2-8 tpi


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## itsme_Bernie (Jul 2, 2013)

Searching...



Bernie


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## TOOLMASTER (Jul 2, 2013)

the spindle is 1 1/2....just trying to figure out if they sent wrong one or if it is just oversized..

i just don't have a 39mm to compare with

- - - Updated - - -

shars


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## kd4gij (Jul 2, 2013)

the ID of the threads on my back plates are 1.348 to 1.355


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## TOOLMASTER (Jul 2, 2013)

i got 1.500 on spindle

plate is 1.515


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## kd4gij (Jul 2, 2013)

Ok it sounds like you have a 1 7/8-8 back plate
http://www.tools4cheap.net/proddetail.php?prod=178back


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## dsh1001 (Jul 4, 2013)

TOOLMASTER said:


> i bought a 1 1/2 8 plate for my lathe but it is very loose..i am wondering if i received a 39mm -4...
> 
> would they both screw on or would one not fit the other at all?



I doubt that a 39mm  4mm (1.535" x .1575") would fit a 8tpi (1.5" x .125") mating thread and if it did, I doubt it would be loose. If they mated up at all, that difference in pitch would tighten things up pretty quick and would probably make the face-plate mount askew. 

P.S., type the word askew into Google and see what happens.


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## TOOLMASTER (Jul 4, 2013)

dsh1001 said:


> I doubt that a 39mm  4mm (1.535" x .1575") would fit a 8tpi (1.5" x .125") mating thread and if it did, I doubt it would be loose. If they mated up at all, that difference in pitch would tighten things up pretty quick and would probably make the face-plate mount askew.
> 
> P.S., type the word askew into Google and see what happens.



thats more or less what I was thinking...I was just trying to give them the benefit of the doubt...so basically this  shars adapter sucks


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## itsme_Bernie (Jul 4, 2013)

I had some bad luck with a Shars backplate recently- big void in the casting- machining it nearly fused the darn thing to my spindle because I had to "load" the spindle with a rag in my hand to keep my backgears from banging.

Besides that, I've had good luck with Shars.

Bernie


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## TOOLMASTER (Jul 4, 2013)

i have one on the way from another vendor, we'll see


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## iron man (Jul 4, 2013)

All of my chucks on both of my lathe's screw on tight to the thread and still connect with the shoulder just fine. Ray


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## TOOLMASTER (Jul 4, 2013)

The lathe came with a plate that i couldn't find a matching chuck for.. unfortunately i cut it dow to make a tool..but it did fit fine.:angry:


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## mclarenross (Jul 5, 2013)

dsh1001 said:


> P.S., type the word askew into Google and see what happens.



Hahahahahahah!! Google has a sense of humor.


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## TOOLMASTER (Jul 6, 2013)

GOT IT NOW...the first one was junk:angry:


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