Pm 1228-vf-lb Lathe Preparations

Take this with a grain of salt, as I am a complete neophyte with lathes in general, but I think
I know that the chart is trying to say. I believe one of the 30/35 tables is used if the final
gear in the change gear chain is the 86 tooth and the other is if the final gear is the 91 (90?) tooth.

I tried cutting a thread with the 86 tooth using a combination that had a listed pitch in
both sets of tables and then measured to see which I got. I then swapped the final gears
and repeated the process, and the results seemed to confirm what I was thinking. I say
seemed as my reference is a cheapie pitch gauge.
 
You could have something, Dan. But, I think there is a mistake on the thread chart on the second group of metric thread settings. Instead of both of them having 30 and 35, my guess is the second group should be maybe 50 and 60.

That's what the thread chart for the Grizzly G0773 indicates, as well as the chart for the Seig SC10. Although, Matt made some gear changes on his 1228. The PM1228 is built on the same framework as the Seig SC10, which is also the base for the G0773.
 
"That's what the thread chart for the Grizzly G0773 indicates, as well as the chart for the Seig SC10"
I think that's the answer, then. I really should just print their manual out, since this is about the third time I've run into issues with this one that were corrected on theirs (must be a revision difference). I'd love to see a list of what all is different on these machines from the SC10, because apart from the absence of an oil ball-port over the power-feed mechanism (mine just has a set screw staked in the hole) I haven't found one, yet. Mostly, our machines are simply missing useless add-ons like chuck guards and leadscrew covers (I think the tailstock might be slightly nicer, or at least a newer & larger model with the MT3 taper rather than the MT2 that had been shipping with the SIEGs)

One thing is for sure, though; my machine really doesn't like running with the 30 tooth change gear in play. I've decided there is a bad concentricity issue somewhere at the final drive gear which was causing my cutting issues ('waves' in the cut paths) and with the different gear in position, man does that gearbox howl every time it comes around the tight spot. Regardless what the thread chart says, I'll be doing something else to get this part to work (already did; I simply turned the thread grooves in the Aloris post like .001" wider at the same English pitch, and it now gets deep enough before binding for proper seating; it was like two threads away from the needed engagement, before. Apparently M14 is a place where metric/standard tolerances overlap)

Be advised, I've heard from two people now that the gears in these lathes (SIEG/etc.) have been known to have concentricity issues. Might be worth spinning the gear through its whole travel by hand to check for binding before you damage something. I know for sure my change gears are much, much tighter at the shaft-key slot, which causes them to sit slightly higher at that side of the shaft by the thou or so clearance of the bore.

FWIW, I read the chart as saying "G-Z91-Z90" vs. "G-Z91/Z86-Z90." This still doesn't make sense as there is no way to get the Z90 gear to mesh with the Z86 --the latter precesses around the former on the banjo without getting any closer. Closest you could get is "G-Z86/Z91-Z90" which is what I did to get the desired 1.4mm pitch (which I then found I can't use for worry of breaking the machine). Considering how the "Z91" depiction isn't even close to the same size in the two charts...I think there's a typo somewhere in there. I'm also not sure if it should be considered 'just a typo' for something so basic and crucial as the threading chart to be incorrect --that's simply low-rent crap, right there.

TCB
 
The manual that comes with the pm1228 is the same manual supplied by Sieg for their lathes. It even calls the lathe a SC10 in a couple places.

Matt said he made some gear changes for his pm1228, so info in the Grizzly G0773 manual may have some misinformation regarding the pm1228. Otherwise, it is worth the effort to download the Grizzly manual. It has lots of good info.
 
I just ordered a PM 1228VF-Lb yesterday, I would like to first thank Franko the photos and information in this thread have helped me a lot, I also ordered the stand for this lathe, and my question is has anyone mounted leveling legs to the stand to level the machine. When I talked to matt about it he said people were drilling and taping holes in the base of the stand and mounting legs to do this. I found some adjustable metal feet on a 1/2-13 stud and was thinking that would work. I was just wondering if anyone has done this.
 
Just received my PM 1228VF-LB this week and am in the process of cleaning it and setting every thing up.

After an initial cleaning I plugged it in to my garage's GFCI outlet and after I turned it on it ran only for a few seconds and then the GFCI tripped..arrgh ..off to the web.. I found other folks have reported this and suggested changing out the GFCI outlet for a new up to date one. (my is 20 years old) I did that today and that fixed the problem. I did how ever discover, to my dismay that I have only a 15 amp breaker feeding the garage and not 20 amps that I have always believed. I guess a visit from an electrician is in order to see how much it will cost to run a new 20 amp or perhaps a two phase 40 amp 220v line to my detached garage... It is always something. I have been running machines in the garage with no problem for 17 years now (only one at a time) but nothing that pulls as much as this lathe ( a new line would also allow me to get some badly needed heat! I do have small 1500 watt heater that I use in the winter time and must shut it off when O use my machines.....

I have a few questions I hope you folks can answer:

Does one need to remove the cross slide assembly to clean the shipping gunk off? I notice that there is some black gunk in the oil that comes out between the 45 degree guides. Is that left over from the lapping they did, and should it be removed and cleaned?

Also the oil port near the cross slide wheel oozes black gung(oil) when the cross slide is fully pulled toward the operator..

The cross slide hand wheel has a tight spot in it that makes it awkward to turn smoothly.. are there any adjustments?
The carriage hand wheel gets very hard to turn when the carriage approaches the head stock...any ides?

One last question: does one need to clean the drive gears where the drive belt and pulleys are located. They are covered with what looks like grease , but it could be shipping gunk?

David G.

Gaithersburg, MD
 
I have a dedicated 20 amp GFCI that was getting tripped by the machine. After making sure the machine does not have a short, I replaced the CFGI with a regular box. Everyone is happy now.

I also have black gunky oil coming out of some of the ports. I will at some point take the entire saddle/carriage/cross-slide/etc. apart and clean really well.

My cross slide does not have a tight spot, it turns smoothly. If I were you, I would open it and make sure you don't have something funny going on with the screw mechanism rather than the wheel itself.

One issue I have is that the dial attached to my cross slide is very tight. When I try to set it to 0 (or whatever else, but usually 0), I end up inadvertently changing the position too. It hasn't bothered me too much but I guess I could pop it off and give it a skim cut.

My carriage gets tight as it approaches the tailstock, maybe just the last 5" of possible travel. It hasn't bothered me, but I think someone got too happy with the bondo during manufacturing. The carriage actually rubs against the body of the lathe, just below the rack that the carriage pinion engages. Maybe you have the same issue but in a different position.

cheers,
Cosmin
 
Update as of today. The final part arrived today. It took a while, but I got it.
It's the revised thread chasing dial.
A few weeks ago, the 0.1" cross-slide/compound and tail stock upgrade arrived. I installed them without much angst. Straight forward enough for even me.

I don't have any further plans for upgrades or additions. I might get around to making a spider for it. I originallly thought I would want to put a DRO on it, but I don't think it would be that useful for the projects I tackle. The clutter doesn't seem worth the benefit. I've got some dial indicators if I need to be that precise.
 
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