[4]

New-to-me HF 7x10. Few Questions Re Set up and Tools

[3]
[10] Like what you see?
Click here to donate to this forum and upgrade your account!

willysp

Swarf
Registered
Joined
Sep 8, 2018
Messages
6
Likes
2
#1
Hi all,

After a few years wondering if I should buy a mini lathe, I found one on the web for a really good price so I decided to buy it. My background with lathes if pretty sad: I have used big lathes but always the owner would set it up for me and I would be cutting. So I don't really know much about lathes.

Anyways, here come the questions:

1- The lathe has never been used and has the thick grease that was packed with. What should I use to clean it? I have a lot of denatured alcohol. Can I use that? I am planning on taking apart all the parts that are covered with that thick grease and then put it together. What should I use to lubricate: white lithium grease or motor oil? When I am doing the cleaning, is there anything I should look for? I have read that it is a good idea to check that everything is straight (for lack of a better word) but I am not sure what to look for...
2- quick change: I found on Amazon a quick change for 31 dollars. The tool post is aluminum and the holders are steel (I believe). Do you think it is worth it? I am on a tight budget so something like littlemachineshop has for 130 is out of the question.
3- I bought the 6 piece cutting tools from harbor freight. My experience with HB is that consumables are not good so I was wondering if I should buy HSS blanks and make my own tools. If so, what blanks do you recommend?
4- I used the lathe today and I noticed that the carriage was moving backward when using the auto feed. Is that common? is there a way to fix it besides using a carriage lock?
5- drill chuck: should I buy the harbor freight one or the one from little machine shop (or any other supplier)?
6- videos or books: is there any book or youtube video out there that you would recommend that starts from zero? for example, I have watched several videos but none explaining the types of cutting tools and the position they should have (all say that they should be aligned with the center of the piece though)

Anyways, pretty excited about my new toy/machine and looking forward to starting my first project.

Willy
 

Z2V

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
May 10, 2017
Messages
633
Likes
587
#2
Welcome to H-M first off. Congrats on your new lathe.
If denatured alcohol cuts the grease them use it. As for the QCTP I would hold out and go with the Little Machine Shop offering when the funds were available. They are a good source for tools for the smaller machines.
There is a great thread on grinding your own HSS cutting tools here
https://www.hobby-machinist.com/threads/models-for-grinding-hss-lathe-tools.62111/
@Mickey does a great job explaining the grinding process and how the different angles all come together to make a cutting tool.
There should be a lever to change the carriage feed direction
As YouTube video go, pick a topic and you will find multiple videos. Tubalcain, this old tony, Joe Pieczynski, just to name a few, all offer great instructional video.
Show us some pics of what you have, we all like pics!!
 

The_Apprentice

H-M Supporter - Gold Member
Staff member
H-M Supporter - Gold Member ($25)
Joined
Jun 14, 2017
Messages
246
Likes
122
#3
What should I use to clean it?
For my mill, which was far better greased than my lathe, I used paper towels, scotchbright pads, and WD-40. No issues.

white lithium grease or motor oil?
Depends where you are lubricating. Generally, oil is for the ways, and grease is for those inner areas near gib strips (but not always).

I have read that it is a good idea to check that everything is straight
Well, you can start with the rollie-dad's method. Plenty of videos on youtube showing this.

I found on Amazon a quick change for 31 dollars.
I found one on Amazon like that a year ago, and it was a scammer who took people's money and RAN with it. Had to file a complaint to Amazon but did get my money back. Later I ordered the same one from AliExpress. Just haven't got around to installing it (yet).

I was wondering if I should buy HSS blanks
Sure, you can buy those dirt cheap from HB as well. I'd use the ones you bought for now, and after you do enough research, feel free to cut your own blanks and see the difference. A really good cut HSS will work better than your carbide. But there is no rush...

I used the lathe today and I noticed that the carriage was moving backward when using the auto feed.
I'm not too sure what this means, as it can be interpreted in different ways. Could you clarify it first? Backward is to where, how is it backward, and continuous?

drill chuck: should I buy the harbor freight one or the one from little machine shop (or any other supplier)?
You can buy from anywhere, I have both the HB and another version from Amazon. I think I wish I had the one from Little Machine Shop, as it's very hard to find those SHORT arbors. But you can always CUT off some of the length on a standard arbor if you need.

6- videos or books:
As mentioned, Tubalcaine has tons of educational vids for machineshop on youtube.

And if you look on Amazon, there are a bunch of mini-lathe books, I have a few.
 

royesses

H-M Supporter - Sustaining Member
H-M Platinum Supporter ($50)
Joined
Aug 23, 2014
Messages
645
Likes
554
#4
Welcome to the forum.
1: I use mineral spirits to clean the protective grease off. Paper towels or rags to wipe clean and dry.
2: The LMS QCTP is high quality all hardened steel. The low cost one of aluminum may be ok for light cuts on soft materials, or may be all you need.
3: The 1/4" indexable carbide tools from HF are decent and are made for aluminum. They will work on steel but may chip or wear sooner. HF also sells a set of round and square HSS blanks in 1/4". You would need a 1/16" shim if you use the original tool post. The machine uses 5/16" tools at center height. LMS has many HSS blanks and pre-sharpened tools.
4: I'm not quite sure what you mean. There is a lever in the rear to change the carriage feed direction when using auto feed. If the carriage is moving out from the chuck the lever needs to be moved to the opposite position. 3 positions are forward, neutral and reverse. A carriage lock will prevent any movement of the carriage. You can make one or buy one. It is not used when using auto feed.
5: The HF drill chuck works ok for most drilling. So if it save you some money get it. I use one all the time.
6: Tubalcaine video's. The Sherline web site has some good info. There are many good books and manuals on the forum in the downloads section.
Mickey and the other members here are a wealth of information also. Read through the stickies in the beginners sections.

Roy
 

Latinrascalrg1

Registered
Registered
Joined
Dec 9, 2016
Messages
90
Likes
40
#5
A heat gun or hair dryer and paper towel will do a great job removing the bulk of the protective shipping grease. Then use the alcohol to clean up the residue that remains before applying the proper work lubricant to the correct areas.
 

mikey

Active User
H-M Supporter - Gold Member ($25)
Joined
Dec 20, 2012
Messages
4,108
Likes
4,441
#6
Welcome to HM, Willy!

Just wanted to add on to the great advice you already got here. Your tool post has to sustain the forces when cutting so you need a decent one. Aluminum QCTP work fine on really small lathes like a Sherline or Taig. Above that, a steel tool post will be better and it pays to get a decent one. I think the LMS steel post would be fine for your needs; I put an OXA on a Emco Compact 8 lathe and it works really well.

I would agree with using HSS on your lathe. You just don't have the speed, power or rigidity to use carbide tooling well. It will work, but not as well as a good HSS tool.

As for the carriage moving backwards in auto-feed, I assume you mean that this happens when the tool contacts the work piece. The only thing I can think of that will allow that kind of movement is a loose or warped cross slide gib. It might be a good idea to take it out and have a look to be sure it is flat. If it is, put it back in and adjust it properly. @royesses knows these lathes well and can give you some good advice on how to do that.

I do understand that you're on a budget but keep in mind when choosing tooling that there are some foundational pieces for any machine that should be chosen with care. Your QCTP holds your tooling and has to sustain all the cutting forces the lathe produces. Aluminum has 1/3 the modulus of elasticity of steel and while an aluminum post won't break, it may not hold under load as well as a steel post will. Your drill chuck is another important piece of tooling. I don't think you need a Jacobs Super Chuck or an Albrecht keyless chuck but you can find a used Rohm Supra keyless chuck on ebay for under $60.00 that will work really well on a mini-lathe. Most important is your choice of turning tools. I highly recommend you learn to grind and use HSS tools; they will allow your lathe to work to its full potential.

I'm happy for you, Willy! That lathe is going to open up all kinds of doors for you - enjoy!
 

willysp

Swarf
Registered
Joined
Sep 8, 2018
Messages
6
Likes
2
#7
Thank you, all, for the advice. I tried denatured alcohol and works great. Regarding the tool post, I will wait and see. I asked about the carrier moving backward. what I think was happening is that with the vibrations, the handle was moving but I am not sure if the carrier was actually moving. I will clean everything, put it back together, and report back.
I don't have any pics. I have the lathe in my shed, which does not have power so I don't have lights.
Thank you again, you will hear back from me soon.
Willy
 

homebrewed

Registered
Registered
Joined
Jul 28, 2017
Messages
124
Likes
63
#8
I own a 7x12 lathe, which is just a slightly scaled-up version of yours. If I'm doing some operation that doesn't require moving the carriage, I lock it in place by engaging the half-nuts. This might seem like a futile effort because the OEM lead screw+mounting blocks have some slop that allows the lead screw to move back & forth a bit. However, just like compensating for backlash, it can be accommodated. If it really bothers you, you can make or purchase a carriage lock.

Above all, have fun with your new lathe!
 

willysp

Swarf
Registered
Joined
Sep 8, 2018
Messages
6
Likes
2
#9
thanks, homebrewed.
So I took apart the chuck, tailstock, the compound and cleaned them. There was a lot of sticky thick grease.
I noticed two things: one is that the spring that goes inside the dial and hold in place the feeding screw ( https://littlemachineshop.com/products/product_view.php?ProductID=1773 ) likes to jump and disappear... luckily I heard where it landed and was able to find it.
The other thing I noticed is that both gibs are not straight. They are 5 dollars each (plus shipping I guess?) but I am not sure if they should be totally straight or they can be a little bit bowed and the adjusting screws can take care of the issue.
What are your thoughts? buy new ones or adjust them the way they are?

Willy
BTW, if found this page with very good pics on how to disassemble/assemble the lathe: https://www.arceurotrade.co.uk/machineguides/C3-Mini-Lathe-Dismantling-and-Reassembly-Guide.pdf
 

homebrewed

Registered
Registered
Joined
Jul 28, 2017
Messages
124
Likes
63
#10
thanks, homebrewed.
So I took apart the chuck, tailstock, the compound and cleaned them. There was a lot of sticky thick grease.
I noticed two things: one is that the spring that goes inside the dial and hold in place the feeding screw ( https://littlemachineshop.com/products/product_view.php?ProductID=1773 ) likes to jump and disappear... luckily I heard where it landed and was able to find it.
The other thing I noticed is that both gibs are not straight. They are 5 dollars each (plus shipping I guess?) but I am not sure if they should be totally straight or they can be a little bit bowed and the adjusting screws can take care of the issue.
What are your thoughts? buy new ones or adjust them the way they are?

Willy
BTW, if found this page with very good pics on how to disassemble/assemble the lathe: https://www.arceurotrade.co.uk/machineguides/C3-Mini-Lathe-Dismantling-and-Reassembly-Guide.pdf
Hi Willy,
It's not uncommon for the gibs to be warped. If they aren't too bad, you can try reversing the bend to flatten them out. Then smooth the running face on sandpaper -- thoroughly clean it so no grit remains to wear the dovetails. I have read that you don't want to totally remove the machining marks because they help retain lube. It also has been said that the gib material is on the brittle side, so you might find yourself needing to buy a replacement anyway. Fortunately they are not all that expensive. If you have a mill, you also could try making your own gibs. Fignoggle has a design for a gib holder you can download for free.

I'm glad you were able to find the dial spring. It is infamous for disappearing into nowhere!

Good find on the pictorial guide from arceurotrade. It looks pretty good.
 

willysp

Swarf
Registered
Joined
Sep 8, 2018
Messages
6
Likes
2
#11
So I put together my lathe. It was not hard and I learned a lot about it. The finish is much better now than the first time I used it, even though I am sure that with practice and learning about set up I might be able to get even better finishes. Having said that, I do not expect miracles with this little guy but I am very pleased so far.
Question: the cutting tools are the HF carbide tips; what speed should I use for aluminum? I know that carbide cuts faster but I am wondering if I can use the same speeds than for HSS cutting tools.
The other question I have is how much you can shave each pass. I am cutting 6061.
Oh, the cutting tool is a hair low so I will need to shim it. I am thinking about buying a cheap feeler gauge, that way I can raise the tools little by little.

IMG_3900.JPG

IMG_3898.JPG
 

mikey

Active User
H-M Supporter - Gold Member ($25)
Joined
Dec 20, 2012
Messages
4,108
Likes
4,441
#12
Cutting speed for turning 6061 is about 500-600 sfm for HSS and about 2800 sfm for carbide. To get RPM, do a simple calculation: RPM = Cutting speed for the material in sfm X 3.82 / diameter of the work piece.

So, for carbide, 2800 sfm X 3.82 / guessing 3" OD = 3565 rpm. In other words, run it as fast as the lathe will go. If using HSS, you would run somewhere close to 600-650 rpm.

As for depth of cut, it depends on the quality, type of insert and the nose radius of the insert. Your lathe is not very rigid or powerful but it should be able to take a 0.030-0.050" roughing cut. You have to try it and see how the lathe responds. With a good HSS tool, I would guess you could take a 0.100 depth of cut easily if the tool is ground for aluminum.

EDIT: I just looked at your pics again and noticed that the tool is red. Not sure if that is HF inserted carbide or HF brazed carbide. If the former, see above. If the latter then it probably doesn't have a chip breaker and no top rake angles at all - it will just be flat. Brazed carbide tools typically are not that sharp as supplied and will cut much better if you hone the edges with a diamond stone first. They also do not usually come with a nose radius and a very small nose radius would be beneficial if this is the case so stone that on, too.

As for speeds and depths of cut with a brazed tool, I would slow the speed to a little faster than for HSS to start and see how the lathe responds; use as much speed as is needed to get the tool to cut well. Brazed tools with flat tops cut with much higher cutting forces so don't be too aggressive at first. I would go small with the depth of cut and increase a little at a time to see what the lathe and tool want from you. A good starting depth is 0.020" deep (0.040" off the diameter) and then go up from there in 0.010" increments. You will reach a point where the lathe will slow or chatter and that tells you the limit for that set of gearing when using that tool bit. You can either slow the speed, increase the feed or change the angle of the tool bit (turn it slightly more toward the chuck). This always works but you may find that your motor lacks the torque to handle deep cuts. That's okay; you've just learned the limit of your lathe with that kind of tooling.

Part of the fun when learning to run a lathe is sorting out how your tools work on your machine. Play with speeds, feeds and depths of cut. Be observant; watch it run, feel it run, listen to it and the lathe will tell you what it wants. You may not understand it in the beginning but eventually you'll tune into it and things will go much better. You are about to learn that a very small lathe like yours will cut with a carbide tool. When you are ready to go further, look into grinding HSS tools to really wake it up.
 
Last edited:

willysp

Swarf
Registered
Joined
Sep 8, 2018
Messages
6
Likes
2
#13
Yes, those HB cutting tools are brazed carbide. I am turning a 2 inch aluminum bar and the speed is 1000 rpm. I ended up with a depth of 0.015" and the lathe was doing well. I noticed that at some point the chips were accumulating between the tool post/cutting tool and the piece of aluminum so the lathe started to slow down. I changed the tool and its angle and I stopped having that problem. Having said that, I needed to stop the lathe to clean the chips after each pass.
I cannot imagine how many little variables are for each material, cutting tool angles, etc. For now, I want to keep it simple. Having said that, I already have HSS blanks and a 30 min video to watch...

This is how much chips I get after each pass:

IMG_3903.jpg


I switched to this cutting tool (I do not know the name...) and I was not having many problem with chips anymore (let me know if I am still doing it wrong!):
IMG_3904.JPG

I noticed that the tip has some aluminum deposits. Is that common? I will look into honing my cutting tools though.
Another thing I noticed is that the top slide has too much play sideways even though I adjusted the gib strip. I bought a replacement (the original is bowed) so I will work on it.

Wilson
 
[6]
[5] [7]
Top