Encad 850 new carriage bushes - 'humming'

[bob_5793]

Hi,

I bought some new bushes for the carriage assembly (6 in total), the carriage was cleaned and no lubricant was near the bushes, once installed and after about 5/10 minutes printing the bushes start to 'hum' slightly- which is obviously some form of vibration/friction. I can spray silicon onto a cloth a run that along the rail, let it dry and it cures the problem - but only for about an hour, but as we do many hours unattended printing,, we can come back to the machine and the humming/friction is not at a good level, I am concerned running the machine like this will damage something.

We bought the bushes from LZ Sourcing, and wonder whether they are impregnated correctly ? anyone else experienced this problem ? We have allowed them a fair period to 'bed in', I assume this shouldn't be happening with 'new' bushes.

 

[Techman]

the rails have ink on them. You cannot see it but it is there in a very thin film. I use a few drops of Rapid Remover on the rails to get that mud off the rails and out of the bushings. I have not replaced a bushing in so long that the spare package of bushings on the shelf have dust on them.

Once your new bushings get a few hundred passes on them they will seat in and run fine.

 

[bob_5793]

Hi, thanks, I will give it that a try, I assume the 'mud' is more than just a water soluble 'film' despite the inks being 'water based'.
I have already cleaned the rail with Iso Prop, but not the inside of some of the bushes - I will have a more thorough go when I am servicing next week and need to take the carriage assembly off, I also assume 'mud' gets onto the bearing areas of the bushes, not just the rail.

 

[OldPaint]

iso alcohol? hummmmm was it RUBBING ALCOHOL? 70% or 91%?????? if iam not mistake, somewhere in my ENCAD 736 manual, i think it said not to USE ALCOHOL to clean the rail.............................

 

[CP Signs]

We had the 1000i, and manual said to use Windex.

 

[Techman]

those bushings are sintered brass. There are millions of poors in it that allow junk to get into them. The ink is microscopic plastic breads. That junk cakes up and gets sticky. Water based products may get the junk out but it is very slow going. It never really worked. One day I had a carriage failure which usually meant changing the bushings. I had to get the job done so I dropped a few drops of Prep on the rails and behold. The junk was washed out and the printer ran just fine. And has done so for the past 6 years on the same bushings. A good solvent such as rapid prep seems to get into the poors and release that junk very fast. Yet it does not dray instantly which allows the rapd prep to carry the junk away from the bearing surfaces. That junk builds up at the end of the travel where you can wipe it off.

That is my theory. All I can tell you is that since using the Rapid Prep for the past 6 years I have not had any problems with the bushings. I just drop a few drops on the rails when the head is moving back and forth.

 

[bob_5793]

For years I've suffered this problem !! hopefully I now have a solution (excuse the pun) ...

In my Encad 850 ref manual I'm sure it refers to using just 'water', and in my 850 service manual 'Iso Prop Alcohol' is recommended (which I've been using) ...

I guess although the ink is water based, it must have 'carriers' that are not, and they are what is getting glued up inside the bearings pores, and on the rail. I assume by using all these solvents to clean its going to wash out any impregnated lubricant - if it is in fact still in there ... but hey if it works then thats all I need to know.

Thanks.

 

[bob_5793]

Bought a small bottle of rapid remover, few drops on the bar seems to have cured the issue, many thanks.

 

[bob_5793]

I want to resurrect this thread.

The problem has actually persisted with carriage axis failures and the printer crashing out regularly.

These were new bearings on, that hummed on the first use, by pouring a combination of chemicals on the rails and bearings I have limped through with erratic success.

Could it be that by not using the rapid remover first on the rail before running the printer up with new bearings, and then using a combination of ISOProp alcohol, WD40 and Silicon Spray I have contaminated the bearings ?? I understand the encads Sintered Brass bearings only have a life of 300hours, and should be replaced at these intervals.

Bear in mind that I only use GX water based inks, so not sure why the Rapid Removier seems to help, if momentarily.

Any thoughts from anyone appreciated.

 

[Techman]

wd 40 is not a lubricant. it is a fish oil based water displacement formula. Silicone is not a real lube either. Both place a microscopic amount of slip that rubs off within a few slides of the head.

Clean the rails really good. As I said above I use Rapid Remover.. to clean. Also I use rapid prep to degrease the rails. The ink overspray will build up in minute amounts and gum up the works.

Then drop about 4 drops of mineral oil onto the rails on each side of the head. Run the head back and forth through the oil. Let the oil soak into those bushings. It does not take much. A couple of drops will make a huge difference. Those are sintered brass bushings. Oil will soak into them. I know every one will scream no oil. The reason some say no oil is because too many people put some manly sized drops on the rail and it will drip all over. And some oils will collect dust and dirt causing other problems. However, this is a machine and it needs some kind of lube. Mineral oil is natural and does not get gummy. It is used in fine machines such as sewing machine etc watches.
Some off shelf bushings have grease in them and it will get gummy or sticky or turn into hard scale.

As I posted above. I have not changed my bushings in years. I just clean the rails every third use with rapid remover and then a couple drops of mineral oil. This encad is heading towards 10 years of usage and it runs great.

 

[bob_5793]

Hi Techman - thanks for the advice, yes I always wondered why the 'no lube' ideology, just wasn't sure which one was right to use though, I did try plumbers grease - which is a silicone based grease - but after one job I simply got the same 'carriage axis' errors - guess that must have caused the gumming up.

It can get dusty in the working environment, I guess key is to keep the rail clean, I even put a few drops of rapid remover on the actual bearings and let that soak in, I'm assuming all the 'gum' also works its way under all the bearings, so a good flushing out, once dry then apply the lube.

I found a tiny bottle in my Wahl Clippers box - and just bought some 'Singer' sewing machine oil - will try that.

I have also bought 6 new bushings from LZsourcing on ebay - a cheap chinese supplier - any one have any experience with these bearings ? I have bought the cartridges from them and they seemed better than most.

 

[bob_5793]

I bought a bottle of Singer Sewing machine oil, problem sorted.
I guess I must have been flushing out any oil from the bushings with the Rapid Remover or Iso Prop thinking I needed to flush out any 'mud', and the thick plumbers grease didn't soak into the bushing.
The bushings were fitted as new, but I should have soaked them in the oil first before fitting.
All the other combinations of fluids/lubricants suggested and tried only had a brief success - ending up in the humming noise/vibration, I now understanding what a sintered brass bearing is and how it is lubricated
Thanks for the replies to get that one sorted, even if it did take a while to get to the bottom of it.

 

[Techman]

great to hear it.
I will be running a print jpb tomorrow to wrap a trailer to act as a display at the side of a parking lot. And will be running some small pieces to place under the open hood of a car to display to the road. Still running those same bushings that were in the old encad starting in 2005.

In fact its the same old encad I got from signmaniac long ago.