PRECISION MATTHEWS LATHE TEETHING -2
ฝัง
- เผยแพร่เมื่อ 6 ธ.ค. 2021
- Part two of what went wrong with my new lathe and the simple fix.
Part one is here: • PRECISION MATTHEWS LAT...
Disclaimer:
This video is for entertainment purposes only. Due to factors out of the control of freeidaho, we cannot guarantee against improper use or unauthorized modifications of this information. There is no warranty written, expressed, or implied for accidents, injury or damages that may result from using any information in this video. Freeidaho assumes no liability or responsibility for property damages or injury incurred as a result of any information contained in this video. Use this information at your own risk. Any injury, damage, or loss that may result from improper use of tools, equipment, or from the information contained in this video is the sole responsibility of the user and not freeidaho. Be safe!
Hi! I think your guess about bottoming out the cross slide and locking up the drive train is correct. This happened to me once, and in my case it broke the cross slide leadscrew nut. I’ve spoken to others who have had various other parts of the drivetrain break when this happens. In your case, the leadscrew got locked up which is why that keyed bushing snapped, and the cross slide bottoming out is a common reason for this. The leadscrew has a brass shear pin in it that is supposed to prevent damage in any crash, but everyone I’ve talked to says they never do their job on this machine. I’ve crashed it twice (carriage and cross slide) and neither time did the shear pin break like it was supposed to. Anyways, this is an older video so maybe you figured all this out already. Just in case, maybe this will help.
Yes, you are so correct.
I actually own this lathe because of you, and your video on hobby lathes. Thank you! It was a great choice for me, and like you, with some care it can make great parts. I originally wanted a CNC lathe to match my Tormach 1100, but gave up because of the cost of them. I love creating new things, but when it comes time to make a second one, I have little interest so CNC suits me fine.
I'm a regular viewer of your videos. Thanks for all the teaching. I'm loving the switcher. I like projects that move.
I appreciate you taking the time to make and post these two lathe fix videos. I’m also looking to order a PM lathe today. Cheers from CA!
Thank you!
Very educational series. I’d like to see the disassembly and cleaning of the machine too, as I’m about to contact them in a few weeks to order that same lathe. Great work!
Thank you Sir!
I like how methodical and patient you are. Reminds me to do the same!
Thank you!
Well done and very humble of you to come to the self-inflicted breakdown. If I had a nickel for every time I've broken a tool, I'd have at least $1.25;-) I too 'am about to pull the trigger on the 1022V and thank you very much for your time and expertise.
You Sir are very welcome. Hope you can get one fairly quickly. The container ship snafu seems to be easing.
New subscriber, thumbs up on the video. Thank you for posting videos of fixing your (then) new lathe, well explained process and owned up to potential mistake in operation. Kudos and respect to you! I also enjoy riding motorcycles, fabrication, and training dogs, cheers!
Thank you!
Nice video, I enjoy your candor, honesty and well deserved respect towards PM. . I noticed in your video prior to disassembly of the gears that the large middle gear had the recessed side out, and you installed it reversed. You did note that with your added text bubble, I assume you did correct that. Not sure what exactly the difference is, a clearance possibility? Also, I, as a welder when seeing the broken bushing I immediately said to myself, "weld it back together". You have a mill so the weld can certainly be cleaned up. But then I thought about this bushing as possible sacrificial piece, and perhaps the weld would make it too strong to break and thus cause damage to the gears (spelled big trouble more expense). Kinda like the auger pins on a snowblower saving you the larger expense of a new auger or shaft breaking instead. But, alls well that ends well, you had the extra piece (thank you PM) and were able to correct the problem. I'm happy to see this video, I myself would probably not have realized the actual cause was the carriage already at the end of its travel... Subscribed and looking forward to more videos on your channel! mike
Yes, I think you are on to something. That little bushing is probably the equivalent of a fuse. Thank you Sir!
So far the lathe has been working great!
Thanks for sharing. I'm thinking about purchasing this lathe. All this info is helpful.
Thank you!
Thanks for the effort you put in making the video, I'm sure many people will appreciate it. I own a very similar version of this lathe (Canadian Busybee) and had similar issues after crashing it but it was a bent shaft in the apron that was the issue. Blondihacks has a video showing her repair of yet another different bent apron shaft on her 10x22 lathe so there are multiple things that can go awry.
Great insight into this lathe. Mine is a very similar Craftex 10/22 available in Canada. I haven’t broken it yet ha ha. Thanks for posting.
Thank you!
I'm awaiting a PM1022 lathe- coming this summer. This was very informative- keep up the videos
Thank you! May the shipping gods be with you!
@@freeidaho-videos Somewhere in the Pacific
Did you check the gears for burrs. Some times "breaking" the edge of the gear teeth with a small file will improve gear engagement
Good Tip. I have only looked at the three gears on the match right now, but the gear teeth were excellent. I still have over a dozen other gears to look at.
Thank you!
When I saw you pull the bushing apart my first thought was that the cross-slide hit the limit and broke the bushing. I am surprised that the drive clutch did not prevent that from happening. That drive clutch tension is adjustable on my lathe (PM1340GT) and is right where the leadscrew comes of the gearbox. Basically, if the carriage hits a stop it prevents the gears from driving the power feed. Looking more closely at your lathe is appears the power feed is driven via the lead screw (which is not the case on the PM1340GT) so maybe they don't have such a feature.
Glad to see you got it fixed, I'd definitely keep a spare of that part. When replacing I would focus on reaming the bushing rather than modifying the shaft at all.
No drive clutch, which would have been nice.
When the keyed bushing wouldn't fit, the first thing should have been using a micrometer to measure the bushing, then measure the bore in the gears. Hammering them together, good luck getting them apart. If the bore was tight, a reamer and some patience using it would have cleared that up a lot faster than trying to polish the stud down. The bushing should be a slip fit, made to be changed, but you're going to need a press to get it out now. Or, to be blunt about it, you bought a Chinese machine that must be considered a kit of semi finished parts. Also, milling the cross slide, the nut is now ten thousandths low, it may bind when the slide is pulled back. I know this is a year later, but I was considering one of these, but decided on LMS instead. Chinese with one nameplate is probably not much different than Chinese with another name plate. Not seeing the gears in person, I may be wrong, but they're probably made with powdered metal and not machined. But for now, my old Harbor Freight is doing most of what I want it to, and while I have a new one from LMS in the garage, there's no big rush to get it set up and in use. Not my first trip with an import lathe, having it and being ready for use are two different things. Until I have it set up, my old HF 9 X 19 will continue to serve my needs. I doubt the LMS is going to be a lot more useful, just half a percent more convenient.
Several changes later, no problems.
The drive nut is in exactly the same position as it was originally. It bolts to the surface I cleaned up, which rides on the base of the cross slide which is untouched.
Good luck with your LMS.
Is there a published amount of backlash for the change gears? I think some backlash is better than no backlash. Thanks for the video! 🙂
Since you're a PM guy and there's some PM guys here, I'm considering the 1022. However I need to get it into the basement myself. Is this doable for 1 person with a handcart, or by skiing it down the stairs? I think I could get it on a dolly myself once I get it down there. Any advice for moving a machine like this is appreciated!
This is a tough question but I will try to help.
Are you young and strong, or have young and strong help?
Do you have wide stairs and are the entry and exit straight shots?
If it were me, I'd make a cardboard or wooden model of the lathe, and see if it can reasonably go down the stairs space wise. The weight will be a lot lot more. You will likely have to remove the lathe from the wooden box to reduce its size.
If it seems plausible, I'd recruit a couple of young brawny guys to help.
I hope this helps.
It would make sense thar the cross slide would be cranked in all the way for shipping to make the lathe as narrow as possible to fit in the crate. I’m guessing that it would be unusual to have it in that position under normal operation.
Thank you!
You don't need to drive the insert into the gears it only will be a light press fit.
The key here is "supposed to be."
So after a year how do you like? Would you have purchased the Taiwanese models if you had to do it over again?
Yes, definitely! I'm not making space shuttle parts. But on the other hand, a good machinist can hold a few tenths on this machine.
Given my budget, it was the choice of no lathe at all or picking the best of the Taiwanese. Thanks to Blondihacks, since she helped me find a good brand.
I have the same lathe... I wonder if it siezing is what broke the key.
I don't know for sure, but I might have tried to drive the crossfeed further than its travel. That would surely stall the whole drive train. At least that is a theory I am going with for now. Since I wasn't cutting a part, I wasn't paying much attention to where it was in its travel.
Generally, particularly on these small lathes, the keys are made from zinc, or a soft (very soft) steel, and are designed to break with too much stress, so that the rest of the machine doesn’t crunch. They’re mechanical circuit breakers. If the machine is overdriven, they protect the entire drive train.
If everything were correct, the bushing should have been a slide fit in the two gears so they can be easily taken apart, which will need to be done for some cutting and threading operations. The short axel for the gears didn’t fit because when you pounded the key in, it caused the ID to contract. The first question should have come when the key didn’t slide in.
Yeah, maybe, but on any of the other gears that came with the lathe, they all fit pretty much the same. No slidey, light pressure to fit. Maybe your lathe is different. I have others using a dowel to do the same thing.
Did you put oil on the bushing?
Of course.
What size is your lathe?
It is a 10x33, PM-1033 is the model number.
This is what happens when you buy substandard Chinese machines. Gone are the days when they were made in the USA like South Bend and Clausing. I’ve been a machinist for 40 years and it’s hard to believe that in this and age people buying machines from China are always fixing them because they are made so poorly. You would never do this if you were to buy a new car. It’s depressing to think that the machine made today are worse than they were in the past yet here we have the most advanced CNC machine-tool technology and engineering yet no amount of it is helping the Chinese make BETTER machines. They also look like they were made by disgruntled workers. What a disgrace this is. There’s no way in hell I would buy a Chinese made machine. I’d rather buy an old Clausing or South Bend and restore it.
Whoa, there big fella. That is a pretty high horse you are riding.
It turns out like I explained, this was my fault, and would have broken any lathe.
When you start paying your own money for machine tools, it sometimes goes like this. Either buy something perfectly capable but not excellent, or have nothing at all.
This is a Taiwanese lathe, a big difference from one from China. The quality is great for the price point and can regularly hold 0.0002" with a skilled machinist running it.
So I chose to have it, instead of nothing.
@@freeidaho-videos The point I was making is that we in the US no longer have any regard for making machines as we did in the past. The problem you had with the keyed (broken) bushing reminds me of my Clausing lathe. It was specifically designed with a well known safety feature: A 0.093" sheer pin on the lead screw in case an operator either cuts too much in one pass or accidentally runs the cutting tool into a shoulder. Repairing it is just a matter of replacing the pin. Whether your Taiwanese lathe had the same intentions with the keyed bushing, I doubt it. Be that as it may, I hope all the best for you and your projects.