Tailstock scratching ways

[Dabbler]

I found an inexpensive stone in 4000/10,000. 1" X 4" - I think I paid 12$.

Now an old school tool and die maker will say that there is no need for a 10,000 stone, but the point is that there won't be any large grit making the surface uneven. You can buy Precision stones in a pair for a couple hundred, but the little stone seems to work better than my precision stones for finding burrs.

 

[matthewsx]

That’s a good analogy. Thank you for taking the time to post this.
Well, your only problem was that it was a tecumseh... lol.

I’m just enjoying the discussion at this point. I enjoy the conversation, as much as completing the objective. It helps me hearing from everyone else, no matter how redundant.

On a side note, would you be interested in giving me some small engine advice? Send me a message if you have the time, or interest for that matter. I have a particularly interesting project I’m building, similar to a racing go-kart.

If the project isn’t secret just post it up on here, we have a whole section dedicated to things that move on their own.

THINGS THAT MOVE ON THEIR OWN

www.hobby-machinist.com

John

 

[Hellkell]

I try my best not to buy Chinese. I check most things I buy. I’m sure most people do the same here. We are sealing our own demise.
Taiwan is a different story but unfortunately probably next on the chopping block. It’s probably worth it for many reasons to spend the extra money and buy their products.

 

[Richard King 2]

Now that Dabbler said it is OK to discuss things. I have a question. Was the scratch on the bed when you cleaned off the Cosmoline? Did you use the machine and then saw the scratch? I see PM has a 3 year warranty, does it cover this?

 

[FTlatheworks]

Now that Dabbler said it is OK to discuss things. I have a question. Was the scratch on the bed when you cleaned off the Cosmoline? Did you use the machine and then saw the scratch? I see PM has a 3 year warranty, does it cover this?

No, I have been watching these scratches appear sliding the tailstock carefully. I noticed light scratching and thought it was chips, so I ignored it. I noticed new one here and there. I cleaned the ways and called it good. I went to do some drilling in a square piece of plastic after the cleaning and slid the tailstock back faster than usual, but being sure to push from the base. This was when this long scratch appeared. I immediately took it off and checked for chips, there were none. This is when I looked at the day one pic of the tailstock, and took a new pic to compare. I noticed no differences, just a poor finish which I was aware of.

 

[Dabbler]

@FTlatheworks I'm sure that there are two factors causing your problem, but I'd love to be near to test them out. I really like to measure these things for myself, not because I don't trust anybody, but as I measure in person I might notice things sometimes missed by other guys.

One factor is that the tailstock isn't perfectly flat, as you alluded to above (this is easier to fix than you might imagine). The second is that there are inclusions in the casting that contain carbides - all grey iron contains carbides, but there is a tendency for carbide clusters to be created near inclusions that contain excess carbon.

By taking a flat stone and lightly stoning the tailstock surfaces, you might very well discover one or more of these areas. This thing isn't directly Matt's problem at PM or at the factory. When I refurbish 80 year old 'best of breed' machines I have to be careful of this as I rebuild them. If you find one, take a diamond hone and relieve it. even if you go a little too far, it won't hurt your tailstock, and will eventually result in wider contact area. Even if it doesn't, you should still be okay.

Note that a few scratches isn't harmful to you lathe bed. They will even hold a little oil which can be beneficial - they just look bad.

WRT to the shape, each shape, (convex, concave or random) has a different strategy that I'm sure @Richard King 2 can give you some pointers about, but that is a very long post indeed. It isn't rocket science, but the strategy has to be appropriate to the situation.

P.S. Taking a stone to the tailstock finish will help take out any sharp peaks, will make the movement feel smoother anyway.

 

[Richard King 2]

What does PM say? Can you return it and get a new one? If I were you I would do that. It doesn't say on their web-site what the 3 year warranty covers. Ita new and it should not have scratches. I was also thinking what sort of lubrication does it have? Did they send a container of oil with it? Did they tell you what oil spec to use? Did you use the oil? If you decide to keep it I have a few idea's for you.

 

[FTlatheworks]

What does PM say? Can you return it and get a new one? If I were you I would do that. It doesn't say on their web-site what the 3 year warranty covers. Ita new and it should not have scratches. I was also thinking what sort of lubrication does it have? Did they send a container of oil with it? Did they tell you what oil spec to use? Did you use the oil? If you decide to keep it I have a few idea's for you.

I haven’t asked for another. I mentioned the situation to them in an email and tech said it’s harmless. I have never told them I need them to replace anything, but I have brought up issues to see what they would do.

Maybe, I’m being sensitive, but I get the feeling that they are tired of hearing from me.
I haven’t asked for new anything. I’m not an expert when it comes to lathes. I can rebuild Diesel engines, auto transmissions, and paper presses that are much more intricate, so I went with my experience from that. This helped in deciding what to bring up with them. I got responses that indicated to me, “we deal with this all the time and we aren’t going to replace anything unless it is absolutely necessary”. I was hoping they would say “ya that’s not right we will send you a replacement and salvage that one, you can send the replacement back”, or something along those lines. I don’t want to be that guy that complains over and over again and strains a relationship I would like to keep happy, so I can continue building my list of machines with them.
Even on this forum, half the people are saying just hone it, the other half are saying they should send another. I was in constant contact with Matt and PM until I bought , then Matt was on vacation for a week, then two weeks. I gave up on calling after this became a pattern. I know I could probably make demands that would be met, but I make sure I’m informed before I make that choice.

I use vactra for ways, I use universal hydraulic/tractor oil for the gearboxes. I oil every time I use the machine. Probably wasteful, but we have high humidity lately and our other machine have had rusting issues. I keep it coated at all times to avoid this on my lathe.

you may notice in a pic the wrong looking oil on the top slide oiling sites, but this was one time I mixed up my oiling cans.

 

[benmychree]

I think that there is just a difference in quality due to the lower price. I have a lot of cheap imported tools that just don't work but kind of live with it, since the price was so low. In this case, I would just try to find the high spot and find out why it is scratching. It may just be a hard spot in the casting, and can be gently persuaded to not be so sharp and proud. I wouldn't return the product. It's a really good lesson, and one that you can well afford to repeat. Just try to make things sort of work. I have posted a few examples, and I'll report some of them here. I bought some Harbor Freight diamond cutoff wheels. I discovered that they would only cut a tiny bit on their perimeter before the thin layer of diamond grit wore away. The disks had plenty of diamonds on their faces for the customer to see, but those did no good for cutting. They were there for cosmetic purposes only. At least the cutters can be used to do some tool grinding, but there aren't really enough diamonds to do much good. I thought the mandrels could be repurposed, but the cheap screw stripped out immediately. I'll never buy these again, but I won't return them. This will cause me to repeat unwanted behavior. I bought a carbide tipped dead center for my lathe from Ebay. I ended up getting sent a mild steel tipped dead center. I know it is mild steel since I gingerly did a file test. I complained to the seller, and they insisted that I send lots of photographic evidence including the file marks. When I sent the photos, they asked me if I would be happy if they returned $1. I said OK. These lathes can do a lot of good work, but as a lot of people on the Internet say, they have shortcomings that need some refinement by the consumer.

Soft dead centers are made to be used in the headstock of a lathe so that they can be trued up with a cutting tool when necessary; often they are marked with a V groove on the big end near the 60 deg. taper

 

[Richard King 2]

How old is the machine? Is it still under the 3 year warranty? You don't have to be a Machine Rebuilder to see and know those scratches are not normal. If you just bought a new Diesel engine and it came with a big scratch in the wall of a piston What would you do? I would think Matt would do anything not to see this inside his sponsored forum. I have also never heard a person call leaving the tailstock domed> Can you slide in a .0015 feeler gage under it? I see your south of KC. I might be driving to Tulsa later this summer. I could stop by and look at it. I would also ask Matt did they forget to install way wipers on the tail stock?