# PM932 headstock gib adjustment  and PM 1236 taper



## RockwellHardness (Nov 20, 2013)

I  have finished the first round of set up on the the PM 932 mill and  PM1236 lathe.   I have only had a slight bit of time on a friends Bridgeport,  and no lathe experience,  so you know I am starting from square one.

Checking the taper on the lathe,  with a 1.3 inch diameter bar between  the tailstock and the chuck, there was only 1 thou difference in the diameter over 22 inches.  I think that is pretty good,  any thoughts ?   


On the mill,  I had previously aligned the spindle to the column,  and then got the column close  ( 3 thou tilt  diagonally  in one plane in a 16 inch span) in the alignment with the  table, and was able to square up a 1x2x3 block of aluminum to with a half a thou,      so now back to fine tuning and  trying to  understand more clearly what all is going on with the mill as far as being all squared up and what  affects what as far as squared up is concerned,  and getting it squared up as perfectly as I can within  the limitations of my tools and the machine.  

It was such a good feeling to make some chips.   Both machines work incredibly well.   Matt and his manufactures got the important things right.

Gibs:   The table gibs are easy to figure out,  and I tried to achieve the balance I wanted,  understanding the tradeoff between  accuracy & repeatability  to ease of cranking the handles.

The Headstock gib I am not sure about.   hard to feel anything cranking the heavy  headstock, so much friction with that drive train.   First,  I am not all that positive I have the direction of the gib taper figured out.   I measured the width  and thickness of the gib top and bottom as best I could,  and I got the width to be the same,  around 1 inch,  but the top of the gib  was about 1/10 inch thicker.    If that is correct,  then screwing in the top adjustment will make things tighter. 

I loosened the bottom adjustment set screw,    screwed in the top adjustment  the same amount or so until it felt right,  then cranked up and down.  I did this until I thought  I could discern the effort to crank was changing,  and stopped adjusting the gibs when I thought the cranking effort  " felt right" .

The gib on the  headstock ended up poking out 1/2 inch below the structure,  and with the adjustment  screw head,  the chip shield will not go back on the upper right corner,  and now  is held on top by only the left and socket head,  and tilts at an angle.  

With the dial test indicator  ( by the way,  I found this really neat shop,  Long Island Indicator service, http://longislandindicator.com   They have allot of good information you would be hard pressed to find anywhere else.   They compare the different  types of equipment and the companies that make them.  

They also sell them,  and  they have some of  the  Interrapids on sale at the moment,  and are just about the lowest price when I  price checked.  I will pay  a certain amount more to support good businesses,  especially  pros like  Long Island Indicator  who have provided such good  info, :soapbox: though this time it was the lowest price except for one place,  and that just a few dollars.  

I had busted my cheapy one,  please do not ask how 

 It shipped the next day,  so they are quick.   They of course can service most of  the  tools worth repairing. 

Hopefully I will not break this one !!   According to the Tool and Die Guy,  the Interapids are worth paying more for.   He has a good video on You tube. )   hung off the spindle and  checked the change when I locked down the headstock.  There was a lot of movement.  Since then I have moved the headstock up and down allot,  and last night I checked again,  and locking down only changed the table 1/2 thou  at 8 inches from the spindle.   Is that pretty good?  The gib must have worn off its high spots.  And I am thinking that with the light cuts in aluminum I am going to do,  no need to lock the headstock ever?  

I have noticed that the table cranks  allot easier now.   So the gibs needs some working in time apparently.   And it could be aided by the lubrication method I employed.   The screws and sliding surfaces are all accessible on the mill,  and after cleaning,  I coated everything liberally with my favorite lubricant,  Fel Pro C5-A Anti Seize  ( copper paste )  This is my favorite mainly because there was a lifetime supply left in the shop when I bought it !!!  

Anyway I think it works,  and you can tell where it is and is not because of its color.   Any thoughts on using this lube?  I will still apply oil to the crank handles and other non reachables.   Do those  oil cans that came with the mill and lathe work,   what do you use in them ?  

Should I post this in the General Section as  most of my questions apply to all mills and lathes ? 

Thanks,

RH


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## Plas62 (Nov 20, 2013)

I have a new PM932 mill myself and had similar questions. I found from a post, I believe on this forum that the the Grizzly G0755 mill is mechanically a very close match to the PM932. I downloaded the manual from the Grizzly wepage and it answered a lot of my questions. I believe the two mills to be mechanically very similar, but the electrical on the two mills are totally different. I have attached a copy of the pdf manual. I am sure Ray and others with my more experience than I will be along soon to weight in.

Jim

View attachment g0755_m.pdf


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## RockwellHardness (Nov 20, 2013)

Plas62 said:


> I have a new PM932 mill myself and had similar questions. I found from a post, I believe on this forum that the the Grizzly G0755 mill is mechanically a very close match to the PM932. I downloaded the manual from the Grizzly wepage and it answered a lot of my questions. I believe the two mills to be mechanically very similar, but the electrical on the two mills are totally different. I have attached a copy of the pdf manual. I am sure Ray and others with my more experience than I will be along soon to weight in.
> 
> Jim
> 
> View attachment 64734



High Jim,  

Thanks for answering,   the Grizzly sight was the first place I went,  even before the mill came.  They do have a very close match on the mill.   I just looked again,  they talk about tightening the gibs,  but do not say which ends are the fat ends.  I Think I have it right,  the top on the headstock gib is the fat end,  just was looking for confirmation I had measured correctly and made the correct deduction.  

I am not sure how we lived without the Internet,  I have learned in one month what would have taken years.  Besides help on this site pertaining to the specific machines I have,  the general machine shop knowledge,  like how to tram.    One thing I picked up was aligning the spindle to the column prior to tramming.   That is not mentioned in the Grizzly manual,  or many other places.   If one looks at 20 different you tubes or writings on one subject,  you pick up something that was left out of the others.   

Any issues with your mill ?      

I just got through calibrating the vise  to the  table with  a mag base and dial test indicator.      The  75 dollar vise from PM is just about perfect after I  took  it all apart, cleaned,  smoothed, and  lubed it.   One thing  I do not understand,  they get the important things right,  but then leave sand in the gear boxes,  crud in the  precision vise,  stuff that does not take much time,  something their most unskilled of laborers could do,  what would that add to the cost, 20 bucks per machine ?   I am not complaining, it is what it is and I knew that ahead of time,  I am just puzzled.  It is the same way with all machines from China in this price range.   I am definitely happy with  capabilities and precision for the price.  With PM I have much more for allot less money than Grizzly.   

I yesterday Matt replied with answers to some  questions I asked,  here they are:

Torque  for the mill bed bolts   and the  column  bolts on the 932,   and the bed bolts on the 1236 lathe ? *There is no spec on that, but just snug, I would say about 40-50 ft lbs should be good for those.

*I used brass shim stock under the column,   any problems  with brass  under the column?  No, thats perfect.​How important is is to change the gear oils on the lathe and mill ?  Are the gear boxes really full of sand from the casting process and metal shearing off the gears?  Not sure how it would come out anyway by just draining.  And do not want to  open up the gear boxes. *Yes, I would change it after about 10 hours of use, for sure

*Grizzly sells some molly lube,   what is your opinion.   *To Expensive, not worth it.  For the lathe headstock, use something like Mobil DTE HEavy Medium, OR Tractor Trans/Hydraulic oil, like this*: http://www.tractorsupply.com/en/store/travellerreg;-universal-tractor-trans-hydraulic-fluid-2-gal *For the mill, a lot of people have been using sae 75W90 or something like that, it works great.*​


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## Plas62 (Nov 22, 2013)

I have not had any real issues with my mill, but I did go through and checked the electrical connections in the control box, junction boxes and the pecker head on the motor. I found some connections that I got 1/2 to 3/4 of a turn out of. 

I would recommend that you do this it can prevent premature failure of your electrical components, definitely do the pecker head on the motor I found several loose connections in there. Make sure you unplug your mill before doing this.

When I changed my gear oil I flushed the head with mineral spirits, I filled it up with mineral spirits rotated the quill by hand through all the gear settings then drain it out and blew it out with compressed air and then filled it with the new gear oil. I used 75W/90 from Advanced Auto Parts. I got quite a bit of crap out of there I'll probably do the same each year when I change gear oil.

Matt was great to work with and I would definitely buy from him again. Your right the internet is a great resource. That's where I've got most of my machining info since getting my mill.


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## RockwellHardness (Nov 23, 2013)

Plas62 said:


> I have not had any real issues with my mill, but I did go through and checked the electrical connections in the control box, junction boxes and the pecker head on the motor. I found some connections that I got 1/2 to 3/4 of a turn out of.
> 
> I would recommend that you do this it can prevent premature failure of your electrical components, definitely do the pecker head on the motor I found several loose connections in there. Make sure you unplug your mill before doing this.
> 
> ...




Hi Plas62,  

I do not have the mill in front of me,  what is the pecker head on the motor?   I did indeed go though and tighten anything I could  see, and there was some things that needed attention.   

I too have been  thinking of flushing, though using  kerosene,  but mineral spirits sounds like a better idea,   should not hurt the seals I would think.  And from my experience with paint thinner,  if left in the pail long enough,  if separates out and the  it can be used again. 

RH


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## Rbeckett (Nov 23, 2013)

Generally  speaking Matt does a darn good job insuring the QC inspections on his machinery is valid and that all the nuts and bolts are properly tightened.  Fit and finish on the PM machinery is and has been pretty darn good and remarkably issue free.  Ray or Matt can help you with your initial tramming and can answer any technical questions you may have too.  Congrats on the new machines and don't forget to show us all some pics of the first project when you get started with it!!! I know in the long run you both will be very happy with these machines and their capabilities.  I know when I was considering a new machine it was a case of selecting the PM I could afford and have the specific capabilities I was searching for.  Those machines are available with so many different levels of options that I was all bogged down trying to decide which options I had to have and which ones were negotiable.  For the money I found very few of the options were negotiable since the enhanced machines were not signifigantly more expensive than the base models when you compared adding the same features to a Grizz, or South Bend.   

Bob  

Bob


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## Plas62 (Nov 23, 2013)

The pecker head on the motor is slang for the electrical connection box mounted to the motor. I've heard them called that for long I didn't think about using the correct term.


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