How to clean your circular knitting machine

Wondering how should you clean your circular knitting machine? Here is an article I found explaining exactly what to use to lubricate and clean your Sentro or Addi knitting machine.
The circular knitting machine factories say that this machines should not be opened and that the grease or oil they use should last many years, but I’ve seen people that have problems and noises since day 1, so I’m not too sure if some of us are just lucky or they are produced with different quality control.
Plus when the machines start making noises is almost impossible to keep working, so it’s definitely necessary to grease and lubricate every part that needs it.
I was using a lithium grease, but I’ll give a dielectric grease a try, and the reason why is because the second doesn’t have petroleum components in it, also, I was reading in a socks machine website Dean and Bean that the perfect product for it is first give it a nice clean with wet alcohol cloths, then apply the ceramic or dielectric grease and after you spray the needles with wd-40 NFTD Dry, which will give the needles an extra lubrication.

I have tried most of the lubricants and the dielectric grease for me was the one that worked best, I tried machine oil on the first time and the machine was still noisy after, so one week later I had to reopen . This next time I used the white lithium grease, and it actually worked fine, but after a while, white greases started to come out through the needles and to mix with the work, which I didn’t like very much, plus it’s not recommended for plastic anyway, lithium grease lasted about 2 months and them my machine noises started again…
So I decided to do a little research, since it’s hard to get any answers from the Chinese factory, and the article above is what I found:

Bellow is the full article on best products for plastic

Q: What lubricant (if any) should I use on plastic bearings and gears?

Wherever possible, you should lubricate plastic components to reduce friction and wear, and increase component life. Tests show that lubricated plastic sliding bearings last up to five times longer than non-lubricated ones.

Even self-lubricating plastic materials, such as PTFE (Teflon), benefit from lubrication. At speeds over 1 rpm, friction for a non-lubricated Teflon sleeve bearing increases, whereas it decreases for a lubricated bearing.

To optimize lubrication of plastic components, you should abide by one basic guideline: choose a lubricant that is compatible with the plastic material. Compatibility must be verified under all anticipated adverse conditions of load, speed, and environment. Incompatible plastic-lubricant combinations often cause operating problems such as stress cracking or failure of the plastic component.

Q: What affects the compatibility between lubricants and plastics?

A: Compatibility factors include the lubricant’s chemistry (base oil, thickeners, and additives), viscosity, and aging resistance.

Chemistry. Typically, lubricants based on silicone, PFAE (perflourinated), most synthetic hydrocarbons (SHC or PAO), or mineral oils work well with plastics. Lubricants based on esters or polyglycols are generally not compatible with plastics, although there are exceptions depending on the type of plastic.

Incompatible lubricants cause plastics to lose dimensional stability or structural integrity, or become discolored. To check for compatibility, manufacturers test physical properties of the plastic material including volume, weight, elongation, strength, and hardness. Each manufacturer sets limits on the allowable change in these material properties, typically 7 to 10%. In evaluating such tests, be sure they reflect your worst case conditions. Both lubricants and plastic materials are more prone to changes at higher temperatures or in adverse environments, especially with high dynamic loads.

Additives sometimes cause a lubricant to react with plastic. For example, solid additives, such as graphite or molybdenum disulfide (moly), can penetrate and weaken a plastic component and should generally be avoided. On the other hand, PTFE solid additives are useful in specific cases such as reducing startup friction or providing dry lubrication.

EP additives used in lubricating metal parts are not recommended for plastic parts. Moreover, large amounts of corrosion protectors or metal deactivator additives used with metal parts are also unnecessary for plastics.

Viscosity/NLGI grade. High-viscosity oils, generally ISO VG 100 or more, are less apt to penetrate and adversely affect plastic materials. For greases, an NLGI 1 or 0 consistency reduces friction and grease-induced noise (grease slap).

Aging resistance. As lubricants age, they are more likely to attack plastic. Therefore, long-term plastic applications call for synthetic lubricants, which have a high aging resistance. Outgassing byproducts of plastic, such as formaldehyde or styrene, accelerate the lubricant aging process.

Recommendations. Mineral-oil-based lubricants don’t attack most plastic materials and offer excellent performance for the dollar in general plastics applications.

However, with the trend to higher operating speeds, higher temperatures, and longer operation, companies are turning to synthetic lubricants, such as hydrocarbon (PAO) types, for plastic bearings and gears. PAO’s offer high aging resistance, compatibility with most plastics, and long-term lubrication within a temperature range of -60 to 320 F.

PFAE lubricants are one of the most compatible types, even with hard-to match plastics. Similar to PAO oils, they offer a good balance between adhesion and wetting of plastic surfaces. Probably their widest use is for extreme temperature applications, up to 500 F. Because of their high cost, use PFAE oils only where necessary.

Silicone-based lubricants also show excellent compatibility. They are suitable for low load applications and a wide temperature range (typically -90 to 425 F).

I also found this in another website:

“Dielectric grease is easy to find (auto parts stores, electric aisle at a hardware store), is silicone based, and should fit your needs. While its primary purpose is for electrical connections, it was a recommended lubricant for plastic gears in copiers and laser printers from several different manufacturers (back when I used to repair that kind of thing for a living).
Whatever you do, stick with silicone and avoid PTFE or lithium based greases. They will react with the plastic, where silicone based greases will not.”

So I had to purchase the Dielectric grease online, and it took a week to be shipped, while I was waiting I wanted to finish a new pattern but I couldn’t because I felt it was going to break, so I went to the hardware store and bought WD-40 silicone spray and WD-40 PTFE dry (that was recommended by Dean and Bean sock machine, also made from plastic).

I will be posting the video as well, but the silicone spray was the worst option of all the other ones I tried, the machine would not move…. But, luckily the grease turned up the next day, so I reopen everything again, and without cleaning this time I applied the grease where there was oil before, when you first open your machine you can see where there’s oil.
One more thing that is good to open and clean is the hand crank, it was the first time I did after 6 months and I found even my hair in it, so I cleaned and greased the bearing inside as well.
It’s been a week since I cleaned and it’s going better than before with the dielectric grease that they also use for printers, which makes sense to me because they have a high load and movement, same as the circular knitting machines if used a lot.
I will be posting the video soon on my Youtube Channel, so Subscribe here and stay connected!



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