# PM1236 lathe Compound Slide Dial.



## Ratz (May 10, 2014)

As I did not want to hijack Morgan RedHawk “Holy cow, my PM1236 shipped!”</SPAN>
located here:</SPAN>

http://www.hobby-machinist.com/showthread.php?t=22392</SPAN>

I am starting new thread of PM1236 lathe Compound Slide Dial.</SPAN>

Will. Thank you for your spectacular documentation of your PM1236 Lathe dials, and here are my results. I think I ordered my PM1236 right after you as I recall your postings and attempted to do a lot modifications you did. I purchased my PM1236 in March 2011.</SPAN>

Would others please verify the accuracy of PM1236 top slide micrometer dial.</SPAN>

I have to use the red scale for imperial measures and black scale for metric.</SPAN>
Other words the little sticker is backwards. I was wondering why I had to keep taking more and more material.</SPAN>

For those who are unable to see pictures I posted the PDF file of all pictures on the server located here:</SPAN>

http://www3.telus.net/oceanready/compounddial.pdf</SPAN>


Cheers,</SPAN>
Radek


</SPAN>


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## pdentrem (May 10, 2014)

Did you notice that Will's dials have the colours reversed compared to yours? Look at the divisions spacing. Maybe all you will have to do is remove the dials and repaint in the other colour and reinstall.
Pierre


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## darkzero (May 10, 2014)

Ratz said:


> While on the subject of metric and imperial, would anyone please verify the accuracy of PM1236 top slide micrometer dial.
> I have to use the red scale for imperial measures and black scale for metric.
> Other  words the little sticker is backwards. I was wondering why I had to  keep taking more and more material. The imperial scale graduation is  actually 0.0008”, if my memory serves me right. See the first photo.
> The cross feed dial is correct, black scale is imperial and red scale is metric.
> ...





darkzero said:


> Did you verify with an indicator? Mine is nothing  like that but I did notice before I had a DRO that mine are off when in  the 50 thou area.
> 
> At 10 thou & 100 thou, the cross slide & compound dials are  pretty accurate. But at 50 thou they are off about 2 thou. It used to  drive me nuts sometimes until I figured out what was going on. After I  put the DRO on I don't compensate anymore as I only use the dials now  for DOC when roughing or threading. My tail stock is only about a 1/2  thou off at 50. Not sure about metric though, never bothered to check  & I almost never use metric, if I do it's on the DRO.
> 
> ...





Ratz said:


> Thanks Will, for a quick answer and all the photos. Yes, I did check it with a dial gauge way back.
> As you, I do not really use metric and if I do as you said is readily available with one button on the DRO.
> As I said, all is well except the compound slide dial. Not having a gauge (DRO) there, I am relying on the dial. Yours looks different, for sure. I am going to recheck everything right now and post my findings.
> 
> ...



Moved from other thread


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## darkzero (May 10, 2014)

Sorry if you saw the chaos. I was trying to move the posts from the other thread but they move in chronological order so it put them before the first post. Instead of doing it that way I just quoted those posts I wanted to move & inserted them here above.


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## darkzero (May 10, 2014)

Ratz said:


> I think I ordered my PM1236 right after you as I recall your postings and attempted to do a lot modifications you did. I purchased my PM1236 in March 2011.



I purchased my lathe in Nov. 2009. My PM1236 thread here is copied/compiled from it's original thread on a different forum.

Not important but I have yet to run into someone online that has the same exact variation as I do. Mine has quite a few minor variations than all the others before & after.


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## darkzero (May 10, 2014)

pdentrem said:


> Did you notice that Will's dials have the colours reversed compared to yours? Look at the divisions spacing. Maybe all you will have to do is remove the dials and repaint in the other colour and reinstall.
> Pierre



Good eye Pierre!

Radek, look at the divisons on my dial for imperial, they are smaller than the metric divisions on my dial where yours is the opposite. I suspect what you have is the dial for the metric version of this lathe. Also notice on my dial for metric, there are only 6 divisions before 0.


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## Ratz (May 11, 2014)

Thanks for your response Pierre. I do not understand the reverse colour part, but the idea of reversing ring is a clever one. The only difficulty I see with that is that graduation marks would then be on the other side of the index line causing parallax error.

Now that I am used to it and know the error it is manageable, but it drove me crazy before I discovered this error.

Will, now that you pointed it out I see on your picture there is 127 graduations per turn on the metric scale. I can not see the imperial scale but I am summing there is a 100. What ring the bell is that I have a 127 graduation on tailstock scale. I am going to see if they got reversed during assembly providing the diameter is the same (wouldn’t that be something?). I see there is unbroken paint on the tail stock wheel so It had to come this way from the factory.

I am going to check it out and let you know.

Radek


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## JayBob (May 11, 2014)

Hey Ratz,

I'd just like to point out that your inch scale (labeled as the metric scale) only has 79 graduations.  I suspect that you have the metric screw and dials, but the imperial "sticker".


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## Ratz (May 11, 2014)

JayBob, you are correct, metric scale has only 79 graduations. You are also right that screw, dial and sticker are mismatched. I never noticed the 79 graduations. The dial was never right since the beginning and I just put it to the lathe being a low cost machine. Every once in a while I really got messed up. Well now I know why.
<O</O
<O</O
Thanks to you all, I now have it all fixed up as I revisited this issue with pictures from Will and all comments provided.
<O</O
About 2 or so years ago, I decided to try the milling machine attachment 400V by Palmgren for the PM1232. Since the lathe was almost new I did not want to use the existing slide for fear of wearing it out with this heavy attachment.
<O</O
I called Matt at QMT and asked him if I could purchase a new slide. Matt was very helpful and said he had a complete used compound rest I could buy from him. I told him I did not care what it looked like. Price was OK so I received new compound rest. I was pleased as I could not find anything wrong with it except it had no turning degree scale and no dial index sticker.
<O</O
I was happy and used this compound exclusively with milling attachment. Although good for small jobs, I quickly outgrew the milling attachment and so it but kept the compound rest portion.
<O</O
Last night I found this old compound rest and realized it had the same dial scale as one in Will’s pictures.
<O</O
I dismantled them both, kept the body and dial holder from the original with the stickers but changed guide screw with nut and index ring (I called it scale in the past). Assembled it and checked it with the gauge. I could not be happier. ) After having to compensate for error over the past 3 years I now have an accurate compound dial.
<O</O
What is kind of ironic, is that I purchased the part which should have come with the PM1232 in the first place. I am not holding it against Matt, I am just amazed how these machines can be messed up. 

Radek


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## Ratz (May 12, 2014)

For anyone interested in the pictures of metric (well half metric) and imperial tool compound.

Thank you all for help.
</SPAN>
Radek


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## JayBob (May 13, 2014)

Thanks for the pictures!


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## tino_ale (Oct 9, 2014)

Hey guys,

I have a new PM1236 in metric, with DRO.

I've also noticed the dials gradiations are off. I think the problem is the screw pitch not being precise. I'll recheck tonight how much the DRO shows for one full revolution (actully, I'll probably do 10 revolution for the sake of precision).


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## Ratz (Oct 9, 2014)

Thanks for letting members know about your difficulty. Please post, and let us know how you getting along.</SPAN>


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## tino_ale (Oct 9, 2014)

Ok I checked my Y axis : over the course of 30 full dial rotation, I get a linear error of 0.035mm (0.0013") as per my DRO. Thats 0.07mm error in diameter.

Error in diameter is 0.002mm per 1 full dial turn. I don't worry about that as I'm relying on the DRO anyway.


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