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I hope this FAQ sheet answers all of your questions, but if not do not hesitate to let me know. You can Email questions to me at Greaser info
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Description and Basic Operation: (and ....More than you wanted to know about grease, oil and bearings :) |
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"The Greaser" consists of 3 main components: Part 1. The body is about 2 1/4 dia. by 2 1/2 tall. This
is like a hollow tube with a closed bottom. It holds the grease. Click the pic to see "The
Greaser" in use Part 2. The plunger, (about 2" dia. X 2" tall) fits inside the body. The plunger is solid with a hole through the center and one O-ring groove on the lower O.D. The top groove is a grip groove to remove the plunger as well as a marker indicating an empty "Greaser". A cone shape is machined in the top end. This taper holds and seals the outer race of bearings, from about 5 mm (.210) o.d. up to an o.d. dia. of more than 24 mm. Part 3. The probe-cap. The probe is used to seal the inner
race, depress the bearing and the plunger, all in one motion,
forcing grease through the hole in the plunger into the bearing
around the "shield gap", through the bearing, and then out
the other side of the bearing. The bearing is then lifted out of
"The Greaser" and it is ready to grease the next bearing.
This all takes place literally in seconds, .....only when using
"The Greaser". |
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| Add- 12/12/02 To Grease or not to Grease: Economics: First things first: I am trying to sell Greaser's. But I also sell bearings. Some that will tell you don't bother to do anything. Some say just oil them. Some will suggest that it is a waste of time to take care of your bearings. Before you buy into any of those lines of thinking, read this FAQ and think about this: I, as do most dealers, actually make more money by selling bearings than I do selling "The Greaser". Most dealers make anywhere from 10% to 40% on bearing sales. Buy 10 bearings at 6.00 ea = 60.00 cost to to you. 60.00 @25% =18.00 profit to the dealer....over and over. Your machine may have upwards of 50 bearings in it. Keep flying = keep buying. Your dealer can count on you to buy bearings and buy bearings and buy bearings. You buy "The Greaser" once @ 45.00 all up, your cost....once. The dealer gets to make all of 15 %-20 -ONCE (6.00). There is not much thinking needed here. Anyone who handles "The Greaser" is as concerned, if not more concerned, about customer satisfaction than profit- period. This next statement is a direct quote from a seller of bearings-"Why should I sell them your "Greaser" product, when I can sell them a pile of bearings over and over. Do you know how much I make a year on bearings? I would be nuts to handle your product" (end quote) I have a test machine -Intrepid- that I ran 275+GALLONS of fuel through in a little over one season. Hard 3D. (go to Pete's Pages-Videos for a sample of that). Greased all bearings once with "The Greaser" and I had one bearing go bad in the heli through all of that running. I replaced, in that time, - the pinion bearing (it turns same rpm as engine, about 16,000). (Tail thrust bearings were greased every 10-20 gallons of fuel) Using "The Greaser" will extend the life of the bearings in your machine and reduce maintenance chores and costs. |
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| How does the grease get into the bearing using
"The Greaser" ? You will note near the inner race is
the "inside" edge of the shield. I call this meeting point
the "shield gap", the line where the inner race
"Almost" meets the shield. It is this area where the
grease actually enters the bearing. "The Greaser" will also grease some sealed bearings, but it takes considerably more force to do so. |
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| How Often Should I Grease The Bearings? As to long term maintenance, my recommendation would be: If you used "The Greaser" and the Union 76 grease, don't worry about them until you repair, rebuild, upgrade. The exception would be the tail thrust bearings. Their respective components are turning upwards of 7000-8000rpm on some machines. Although the bearing itself, in rotation, is doing little, maybe 60 degrees total rotation, its environment calls for greasing often. The centrifugal force at 7500 rpm simply slings the grease out. There is considerable thrust load on these bearings as well. As they are last bearing in the stack up (most out board), and not much to stop grease exit, they are the first in the machine to be without grease. The second would be the head thrust bearings for the same reasons. The design of this bearing will have some effect on its longevity as well. It is the "cage" design that can help. The cage separates the rolling element in a bearing. If you inspect the cage closely, you will see, on some thrust bearing designs, that the cage lip is formed up. This creates a reservoir for the grease. When installing this type of thrust bearing, place this "reservoir" facing inward.
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| How much drag is added to a greased bearing? Any grease added to a bearing will increase the drag slightly. The U 76 did not create what I felt was excessive drag on the bearing either. Note that the bearings will feel a little draggy compared to a new bearing, but "The Greaser" greased bearing will expel excess grease to its own "operating equilibrium" for the condition it is used under. In other words a bearing in a clutch support block turning at 10,000 rpm, will expel more grease than a main shaft bearing turning at 1700 rpm. A bearing with no grease will have very low resistance....for a while :) same for an oiled bearing. A greased bearing that has grease that stays in it, at an adequate amount, will out perform an improperly lubed bearing, both in longevity an smoothness. | ||
| How much grease is in a new bearing? Most new bearings seem to have a minimum of grease and a very light duty grease as well. Keep in mind that the bearing manufacture has no idea where that bearing will end up, so it is my feeling that a middle of the road, low viscosity grease is used. These "stock" greases are "gone" in some instances on our heli's, in a matter of minutes of running. In other areas they are diluted easily with fuel residues and also cleaning fluids we use on our heli's. The U76 grease has worked well in all of these instances. | ||
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| What about wiping the excess grease from the
bearing after running my heli? Clean the excess grease from bearings after the first two flights. Thereafter try not to wipe the bearing areas when cleaning the machine. The small amount of grease that is expelled around the shield will collect dust and "crust" over. This can actually act as a barrier that keeps dirt out of the bearing itself. You can also pre-spin the bearings before installation. This will force out most of the excess grease. 600 RPM is sufficient. |
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| Type of Grease: I use Union 76 Multiplex E.P. #2 Grease. The E.P. is for extreme pressure. The grease is lithium based and has a dropping point of deg C=270, Viscosity=152. It is green and it is kind of a smelly grease, fortunately we don't have to handle it much when using the "Greaser" :)I use this grease for all of my bearings, even the smallest of them. Although these bearings don't have any significant rpm to deal with, some are subjected to heavy loads from cyclic inputs etc. Small bearings on flybar mechanisms, as an example, are subjected to centrifugal forces from the rotating components they are attached to, even though they may not rotate as a bearing more than a few degrees. This can cause the grease to fly out of the bearing. The U76 grease seems to stay put under these types of conditions, better than any I have tried. It should be noted that I have not tried every grease out there, so there may be something better. |
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You can go to the Union 76 web site to get the specs
for this and other grease available from "Tosco
Corporation" "Tosco
Corporation - 76 Lubricating Greases"
This grease can be found at Union 76 truck stops. You can purchase this grease in tubes from Pete's Hobbies, if you are unable to locate it A 14 oz tube is 3.50 + ship. |
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| What about other types of material base grease,
other than Lithium? I had done some early testing with Aluminum Oxide based greases(#2 category), Teflon grease and Silicone grease. I had poor results with them. They tended to disappear quickly from the high speed, high heat and high centrifugal force bearings. In some instances it was gone in a matter of a few tanks of fuel. In other checks a gallon or 2 and there was no sign of it or most was gone. Some of these results may have been due to low viscosity alone. One grease I tried, at 14.00 for a couple of ounces (Teflon grease), I expected to be there at the very least after a short run. It was gone as well. The failure rate of the bearings seemed about equal or only slightly better than bearings that were stock. These were classified as #2 greases, Marine grease, Waterproof grease, etc. I quit testing and using these and others like them as well as any grease that seemed to have a low viscosity. There just was nothing left there whenever I tore the heli down. I had an instance where I had left a bearing in the clutch support bearing block that had been greased with a red Aluminum Oxide based grease. It failed at about 15 gallons of fuel. The replacement, greased with the U-76 now has 40 plus gallons on it. I do plan on testing some other greases, and have just added U76 NASCAR Grease with Moly, as well as another grease with a polarizing additive to the top of the list to be tested. This testing takes time, so don't expect to hear anything on these for a while, But I will add any new info here as soon as I feel it is credible. New info or updated segments will be color coded to identify new additions. |
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| What about Slick 50? I have just finished some
preliminary testing of Slick-50-one. It should be noted that this
grease contains what I believe are PTFE solids. I called Slick-50
direct to get some input and when I mentioned use in small bearings
as in our helis', they basically blew me off. They said they had no
test data on using their grease in the small bearings we use. They
said that their grease works fine in cars and trucks, but we were on
our own as it pertains to our particular use. No, they do not have
any plans to do small bearing tests in the future. My concern with using a grease with solids is this: Depending on what size and shape (solid balls, hollow spheres, flakes), the solids could possibly cause the balls to skid, causing flat spots on the balls. It is also possible that they would cause no problem, if small enough or large enough. The person I talked to at Slick-50 agreed. I did do some testing with "Slick-50 0ne Grease" and found, as have others, the bearing felt "gritty". I ran a main shaft bearing in the lathe at 2500 rpm for six hours. The outer was locked in place. The inner was locked on a main shaft. After the 6 hours the bearing felt a little better, but still had the "gritty" feel to it. For these reasons I cannot recommend using any grease with solids that you can feel in the grease. For those who have used this grease, I would not worry about it and I certainly would not take my heli apart to replace it. I would change it when I had to do a repair etc. It is possible that after more extended running the solids will be mashed into the race, or pulverized into the base grease and could end up being a benefit. If any one accumulates any run time info on using this grease let me know. |
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| What about oiling the bearings? I don't recommend oiling the bearings that have been greased as this would tend to wash out and also lower the viscosity of the grease in the bearing, allowing/causing it to be expelled from the bearing much more quickly. Rev. 01/19/03 Oiling the bearings while in the machine will inevitably wash dirt into the bearing as well. It's Simple-"If" you can get oil into the bearing, you are also getting dirt in at the same time. Another down side to oiling bearings is there is little or no "seal" formed by the oil. Problem associated with the "oiling" method of maintaining your bearings: How do you know when to oil them? Can you be sure your bearing is lubed properly in the middle of a flight? How do you get to all of them? Note: Part of the rating on grease has to do with it's "sealing" capabilities. The exception to greasing here would be the one way clutch bearing (Torrington bearing). For the present I have settled on oil for this particular bearing. The rolling element here (needle bearing) only moves for a very short duration, on engagement and disengagement. Its function depends on the bearings moving freely "up" individual ramps in the outer race, forcing the needle bearing to wedge against a shaft. Disengagement requires the "needles" to let go and return "down" the ramp. Friction and force are what make this "bearing" work. Grease could interfere with this action, if it impeded this action in either direction. A few sticking needle bearings could leave all of the load on engaged needles and their ramps, causing ramp failure. The Reverse can be true as well - a bearing that does not release. I will be looking into the Torrington bearing further, as soon as I get the chance :) As a side note, (or two) I use WD 40 on the tail rotor output shaft to clean it. This removes the grit and grime and lubes it for the day. I usually do this every session. I also "lightly" oil the main shaft around the washout hub and swashplate with any oil I have handy. Also, I do lightly grease the plastic main gear. I have found that it reduces the running temperature of the gear. (Checked by point and shoot Raytec sensor) (didn't really know where to stick this item :) |
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| What size bearings will "The Greaser"
accommodate? This tool will grease bearings from 4.5mm(.220") O.D. to over 24mm (.950) O.D. "The Greaser" will actually accommodate any bearing where the INSIDE Diameter of the bearing inner race/"shield gap" is 25mm or less, but the o.d. of the bearing is much larger. This covers ANY bearing in RC helicopters and RC cars as well as roller blades, skate boards, roller skates, inline skates, fishing reels, and other equipment bearings. Some bearings can be greased while still in their component parts. Examples: - bearings in some main shaft bearing blocks, clutch bells, swash plates, and several other components. On a large bearing that is "out of its part", as long as the "shield gap" diameter is smaller than the largest dia. of the V-chamber, the bearing will take grease. This even if the rest of the bearing overhangs the V-chamber. |
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| Why bother to do Small bearings - like those in
bell mixer arms etc. Some considerations for using Union 75
Multiplex E.P. #2 in the small bearings: These bearings can be subjected to fuel residue from flying, fueling, etc., as well as cleaning solvents. All of these things can lower the viscosity of the grease in the bearing. A low viscosity grease, which is what seems to be in new bearings, will tend to break down to an even lower viscosity when subjected to all of this. This can also lead to dirty residue "seeping" into the bearing. The higher viscosity of the U76 grease appears to slow this process down. I have re-greased bell crank bearings that had been on my Intrepid for 20 plus gallons of 30% nitro fuel. These bearings had initially been greased with the U76 grease. I found that when re-greasing, the expelled grease was clean for the most part. This means that I observed more discoloration from dirt/impurities further into the bearing, when the bearing had been greased with the low viscosity greases I had tested. Keep in mind that these are my observations and that I did no "scientific" tests. It can be somewhat subjective in its analysis, as we are talking very small amounts of contaminated grease that are observed when re-greasing a bearing. That initial layer that comes out of the bearing, that has some impurities in it, is mighty small. Also keep in mind that a "fancy" light colored grease will tend to show the impurities easier than the darker grease. |
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| Can the bearings be damaged by using "The
Greaser"? The actual use of this tool to pack your bearings
will not damage the bearing in any way. Packing used bearings that
are dirty could force dirt into the bearing. This of course, would
not be good. Take time to clean the outer of the bearing prior to
greasing. If the bearing is extremely dirty, clean with solvent as
noted in "Cleaning" and "Cleaning Used Bearings"
elsewhere in this FAQ sheet. Excessisve force when greasing can break very small bearings. Go easy. Let the Greaser do the work. I have had a couple of bearings pop the shield out when greasing. |
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| What about cleaning the machine after Installing
greased bearings? When cleaning, try to avoid getting your cleaning agent on exposed bearings, whether you have used "The Greaser" or not. These cleaners can "cut" the grease and lower the viscosity of the grease, which leads to quicker loss of grease, as well as washing dirt into the bearings |
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| Bearing Descriptions There are many types and grades of bearings made from many materials including stainless steel and also Ceramic. The bearings we will deal with here will be steel and/or stainless. Bearings are open, shielded, or sealed. We will deal with mainly shielded, which is what the majority of the bearings in your heli are. If you examine a bearing closely you will see that the bearing has the inner race, a shield, and the outer race. Shielded bearings are covered on both sides with a thin cover that is held in place near the outer edge of the bearing by a clip or the shield is "staked". The inner edge of this cover is not a tight fit to the inner race of the bearing. It's a close fit, but small particles can get through. It will keep out rocks :) Sealed bearings can have a metal cover with a plastic cover under it, which then seals against the inner race, or it may have a plastic cover only. A sealed bearing will have more drag when new and when the seal wears enough, it becomes a shielded bearing :) Some machines may have one or 2 sealed bearings and sometimes open bearings can be found in gear boxes. |
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| Gritty, Notchy, Notchy/Springy, Bumpy bearings,
what's the diff? While on the subject of not so good feeling bearings, lets agree on a couple of terms. Gritty: a bearing that has contamination such as dirt or grit, (PTFE solids fall into this category) in the lube. Can cause balls to lock and skid and could cause flat spots on the balls. Can usually be solvent cleaned and eliminated. Notchy when out of the part: usually caused by flat spots on one or more of the balls. This can be from lack of lube, skidding caused by contamination, and as in the case of main shaft bearings, high impact load such as blade to ground strike or a even a boom strike. This can put a flat spot on the ball. And of course there are other causes -poor material used for the balls and races, etc. Cannot be salvaged by cleaning/greasing. If it is notchy after thorough cleaning and re-lubing -trash it! Can cause mild to severe vibration. Notchy/Springy when in the part: When the part is moved slowly, the part will "spring" back or ahead at certain points of slow rotation. Caused by over tightening of components, or bore diameter is to small, actually "squeezing" the bearing out of shape. Disappears when parts are loosened or bearing is removed from the part. Can also be caused by an over size bearing outer or under size bearing inner. The race "groove" can be narrowed by over tightening a bolt that passes through the bearing inner to hold the part on. The bearing feels notchy/springy because the balls in our bearings are not perfectly round or exactly the same size. When they are moved in the narrowed race one will pass freely and the next will not pass freely through, resulting in a notchy/springy feeling. If the "groove" is freed up early enough and the tightness is not severe, usually there is no damage to the bearing. If severe binding is present, especially in very small bearings, the race or cage may break, destroying the bearing. Bumpy: This usually comes from bearings that have not moved in quite some time. The oils have dissipated leaving the base material behind. Imagine it as hardened wax in the race. Soaking in solvent to clean and re-greasing usually salvage this situation. Note that when a bearing is cleaned of all lube, it will feel "Notchy". Lube the bearing after cleaning to determine if it is any good. |
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| SAFETY Cleaning Solvents and Drying Bearings: I use mineral spirits for initial cleaning when bearings are used and need to be totally cleaned, and then electric motor spray to finish cleaning. Use with adequate ventilation, wear safety glasses to avoid getting solvents into the eyes, and never use compressed air to blow the bearing into high speeds. This can cause the bearing to expel the balls as high speed projectiles and can cause great harm. The electric motor spray dries very quickly and cleanly so air should not be needed. | ||
| Cleaning New Bearings: New bearings should be
wiped clean with a lint free cloth on both sides before greasing.
The expelled grease should be discarded so as not to contaminate the
grease you want in the bearing. Grease that is on the bearing from
the V- chamber side of the bearing can be returned to "The
Greaser", if you know it is clean. Discard the grease expelled
from the "probe" side. "The Greaser" very
efficiently forces the original grease out of the bearing. A slight
twisting motion as you grease the bearing will insure that all the
"stock" grease is forced out. |
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| Cleaning and Greasing Used Bearings: Used
bearings can be greased after wiping carefully on both sides. If the
expelled grease looks clean, and the bearing turns smoothly, bearing
performance is usually satisfactory. If in doubt-solvent clean the
bearing. Discard the expelled grease and the grease on the V-chamber
side of the bearing when greasing used bearings. New or used bearings may be solvent cleaned, dried, and then greased. If using electric motor spray as the final "rinse", the bearing will be ready for new grease in a few moments, as most electric motor spray solvents dissipate very quickly. It is important that all components be thoroughly cleaned when doing used "component" type of greasing, i.e. - parts that still have the bearing in them). This will insure that dirt and/or contaminated grease from in-between the two bearings, for example, is not forced into a bearing along with new grease. |
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| I want it to be clear that I do not profess to be an expert on all of this and that all of my tests are "informal". Having said that, I do prefer the U76 grease for all bearings in my machines, over any other greases that I have tried, including some purported "Heli" greases. I will be doing testing on other greases and will post results here. | ||
How to grease bearings still in parts: You can
grease many components with the bearing(s) still in them by placing
directly into the V-Chamber. For some parts, such as a bell crank
with double bearings in it, you will need to fashion a plate to fit
over the V-chamber. This plate can be made from any stiff material. Click the pic to see parts being
greased with the bearing still in place This plate will need a hole in it large enough to see the bearing inner race. You could use a large servo wheel, thin plywood 1/8" or so, flat fiberglass, plastic, or G-10 sheet, for example. The plate needs to be large enough to cover the V-chamber of "The Greaser". Make a hole in your flat stock. The hole needs to be large enough to see the inner shield edge or ("shield gap" (see ref "How grease enters bearings") where it meets the inner race. Place the plate on the V-chamber, place the part with bearing on the plate so the center of the bearing lines up with the center of the hole in the plate, then use the probe/cap to press everything in the normal manner. |
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| Parts with 2 or more bearings These parts need
to be turned over after grease appears on the bearing closest to the
probe and done again, if the "bottom" hole was not
plugged. You can do parts with 2 bearings, in one shot, if you plug the center hole (bearing I.D.) of the bearing that will be closest to the plate. I use cork plugs from the hardware store. By plugging the lower bearing center hole, you will force the grease to go through the shield into this bearing and on to and through the second bearing. Many other components can be greased this way. |
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| Parts that need no adapter Some components will fit over the "Greaser" without using an adapter plate, like the swash plate and clutch bell. These components will need to have the center bearing hole plugged from the "bottom" side as well. The side that is going to be closest to "The Greaser" This again, will force the grease to go through the bearing by way of the shield gap. When doing a clutch bell that has a ball type bearing in it, even when being very careful, you may get some grease on the clutch lining. Just wipe the excess off with a dry paper towel, then use a paper towel wet with acetone or alcohol to clean the residue from the lining. I prefer to spin the bearing up after greasing, at about 600 RPM. This expels most of the excess grease from the bearing. Some components like the bearing in a torque tube support bushing can be done by placing the whole component into the V-chamber, with the bearing up. Then press with the probe as usual. | ||
| Accessories for "The Greaser" As to
accessories for "The Greaser", I am in the process of
getting adapter plates for the parts with bearing still in,
available. They will have various size holes, with some blanks for
making your own, but they are not ready yet. I am still testing
different materials for both usability and keeping costs as low as
possible. I am also developing a kit for cleaning bearings that will have a bearing clean in a matter of 30 seconds or so. Initial tests are excellent but this also is not yet ready to bring to market. |
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| RC Car Bearings: As to the bearings in your RC car-If you soak them in a solvent-mineral spirits as an example, then clean them with electric motor spray, you will find they come quite clean. They then can be re-greased with "The Greaser". For RC cars the grease choice would be different in some cases, depending on the end use of the RC vehicle. If I were off-road running it I would tend to use the U76 grease. If on a clean environment and racing, I would look to a very, very low viscosity grease. "The Greaser" will quickly and efficiently grease any bearings found in equipment. | ||
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Added:1/15/03 |
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Revised: February 13, 2003