Jim, the 3mm ID is for most all the axles. The 6 mm OD would necessitate drilling a 6mm hole in the journal. It's been reported that when the Aristo inserts are removed, the 6 mm fits right in. This unit has a flange with will keep it in the journal right nicely.
I've used some without the flange and if you don't drill the hole at the proper depth, the bearing did not work properly.
In the recent past, I've done away with all the ball bearings in the journals and just run straight metal wheels. Mostly Bachmann with very good success.
Jim, Stan is correct these are the perfect fit in Aristo trucks the ones on the book marked page that I posted. And as Stan said just remove the the plastic bushing using a drywall screw. Screw it in a turn and pull it out, simple. 99% of axles work better and track better because the shoulder takes some of the slop out wheels, same as adding washers but if you what they are easy to flush mount using a counter sink bite one rotation does it. They go thru switchs better going forward or backward with the shoulders out and you can fit an electrical eyelit on first pushing the bearing thru it into the truck if you need addition power pickup, great for tenders or cabooses for better lighting with now flicker. lI have never had to lube these even on the cars that are left out 7x24. Buy 8 and try one car for 8 bucks you will be back for more. On my heavyweigths my new Pacific could only pull 7 before I got slip on some curves, but after adding these I had one Pacific (New edition) pull all 8 of my PRR and then added my 5 Sante Fe heavyweight coachs. Only problem I have run into is if you get an uncoupling going up a grade the back of the train will roll to the low point no matter how far away it is. I stoped the train to add some cars uncoupled them turned to pick up couple cars and when I turned back half my train was a runaway and boy did it run. Jake
The bearing mentioned (3x6x2.5) works very well in the Aristo Bettendorf trucks, depending on whose
axles U use, U may have to polish them down a little to go thru the bore of the bearing... They can also
be fitted to Aristo's Barber truck very nicely, but its a good bit more work an I don't think its worth the
trouble or expense because the factory bronze bushings R quite free rolling the way they they R...
For the moment, put aside whether or not the Aristo ball bearings (#25529411 tube of ten) will fit this or that truck. For those of us who have been using them in conversions, what came in the mail to me today may be of interest, regarding the first post of this thread--
Last fall, I ordered a couple of tubes of the Aristo bearings from my favorite dealer, at $20 plus change per tube. Last month, I ordered five more tubes, along with some other items; the shipment came only including two tubes of bearings, at the same price. Today, the other three tubes arrived--with sticker shock! Now, I am aware that Aristo raised prices 20% at the first of the year, but here is what I found:
Aristo sticker price-$39.00
Favorite dealer's store sticker--$33.15
Favorite dealer's on-line site price--$24.57
Same product from online bearing vendor--$10 for 10
I want to give my business to My Favorite Dealer, but guess where my future bearing orders will be placed--hint--reread first post of this thread.
Is there really a huge advantage to ball bearings? When I lube the wheels in the plastic journals they spin pretty freely. I can see in a heavyweight, that makes sense. but those of you who use them--do you really notice a large improvement?
Unfortunately I just checked the site and the bearings in question are on backorder with no estimated arrival. You know, these guys are buying them from somewhere and reselling them. If we could figure out where they are getting them we could get them even cheaper.
Lownote-- I agree, for typical rolling stock. I model in 1:20, and the Bachmann freight cars roll just fine with a drop of lube on each journal. However, I am installing BB's on my hoppers because they are used in actual ballast service, with a 5# load of crushed quartz in each of four cars. Even with the stock "friction" bearings, they roll well, but I want to reduce drag when loaded and in a long train. As for the AMS J&S passenger cars, they rolled like cement blocks until being retrofitted with BB's. Also, an AMS caboose that is being fitted up as a RC/battery car has them installed because of the weight. When poor performing trucks or very heavy loading are involved, BB's are definitely worth the effort to install them.
rpc7271--I have no objection to a hobby provider making a reasonable markup when repackaging items like these to make them readily available to us, but I have to balk when it is taken to an extreme, as this case seems to be. Aristo is probably getting them at the same bulk price as the on-line guys selling them for a buck or so, and they must be making a profit at that.
Not that its any big deal, but I personally buy wheels with BB on the axle. one side or both. because that frees the wheels (independently) to go different speeds around curves , thus reduces drag. That on my heavy cars is where its important.
The "real" trains don't have as tight of curves as we do.
I would not spend the money on the other unless I can find a reason for it.
Oh, I agree BB wheels are the best but it is an issue of econmy with some of us. I have Aristo roller bearing trucks on most of my rolling stock but now that the price on them has gone over $22.00 a pair I can't afford as many as before so I have to look for alternatives. Then even with ball bearing wheels I find that the axles still rotate in the truck frame. The ultimate setup would be double ball bearing wheels with bearings in the truck frame. When i win the lottery I will do just that.
Marty, I agree with what you said about using the bearing wheel set. But I can do an entire car (8 bearings) for less then what you pay for one axle. This gives me more to spend on cars or engines. Do you need them Yes and No, if you are pulling a train with 1-30 cars No but more than that with any kind of curves or hard grades mixed in and you will notice with the more you add. I have a 1st run u25 with no additional weight and it will max out at 20 cars on my layout with no bearings. Now the same engine will pull up to 70 cars before the same effect starts showing up. Now do I always use it with 70 cars, No its usual train is 15-25 cars so why the bearings well why maintain your car engine to make it last and be trouble free. I have a laser temp sensor when the engine make 4 loops on my 1200' of track roll the engine over and the temp. is 109 deg. Now the same engine the same 4 loops but the same number and types of cars but with bearings and the temp comes in at 89 deg. Remember the basics, heat is the enemy of electronic devises and motors. So yes do I need them now No but do I want to have the engine for the long haul, Yes. I am an Electrical/Mechanical Engineer and work for one of the largest utility company in the US and these practices apply whether you are dealing with an Aristo motor or one that lifts a elevator with 40 people 50 or more stories. "Less heat longer life, Less maint." Jake