Sintered bronze bushings for the classics

[Killerbug]

For those who can't get it strong enough, these bronze bushings will outlast and outcast anything.  I run bronze bushings in my Amb 5500 since 1980, and it can still outcast any ball bearing tuned Ambassaduer in my arsenal.

http://shop.lundgrensfiske.com/product.asp?product=13523

[inhotpursuit]

how do they hold up against salt water?

[Makule]

For those who can't get it strong enough, these bronze bushings will outlast and outcast anything.  I run bronze bushings in my Amb 5500 since 1980, and it can still outcast any ball bearing tuned Ambassaduer in my arsenal.

http://shop.lundgrensfiske.com/product.asp?product=13523

I'm confused.  If it's stronger, smoother, and can outcast and outlast BB reels, why did Abu convert to BB?  Bushings should be cheaper.

[Irish Jigger]

I would think that sintered bronze bushings would be more expensive to manufacture than stock Chinese bb's.

[Makule]

I would think that sintered bronze bushings would be more expensive to manufacture than stock Chinese bb's.

It's essentially only a sleeve, and the Chinese should be able to make it cheaper than their BB (only 1 piece with nothing to assemble).

[Ken_D]

Once sintered bushings are worn in, for the average baits and spoons, they are quieter, cast further than, and do not corrode and sieze up like ball bearings are prone to do if ignored.  They can hold up to 20% of their weight in oil, and are defeated if greased. 

[GulfOfBothnia]

For those who can't get it strong enough, these bronze bushings will outlast and outcast anything.  I run bronze bushings in my Amb 5500 since 1980, and it can still outcast any ball bearing tuned Ambassaduer in my arsenal.

http://shop.lundgrensfiske.com/product.asp?product=13523

Is the price 179 SEK per one bushing or a pair?

BTW was it this site that was selling AR posts?
I can not find them any more...

[GulfOfBothnia]

Once sintered bushings are worn in, for the average baits and spoons, they are quieter, cast further than, and do not corrode and sieze up like ball bearings are prone to do if ignored.  They can hold up to 20% of their weight in oil, and are defeated if greased. 

How long it takes for those to wear so that they became to full operation? 100 casts? 1000 casts?
Can the process be speeded up by polishing the bushings? Or would it possibly ruin them?

Is it really so that these would cast longer than high quality bb - including ceramics?
I am a little bit suspicious... is there any "hard evidence"? But this really sounds interesting.
Are there distance casters / surf casters in here to convince us - or at least me?

[Nuvole]

Are you trying to tell us that bearing are invented for no purpose, and all engine & motor should revert back to bushing?

[Alto Mare]

 Penn had it right in the biginning. Bushings will last forever and they only get smoother with usage, no worries with friction there.

[JGB]

Lets inject some conceptual info on sintered bushings.

Sintered bushings are manufactured by pressing powdered metal into molds and heating it where the powder granules fuse where they contact each other. This produces a  matrix  (kind of like foam) that will absorb oil onto the spaces by capillary action. The metals are soft and have some natural lubricating qualities (zinc, copper, lead). Stored oil will migrate from the bushing to the space between the bushing and the shaft (provided the gap is small) through capillary action ( this why grease will not work in a bushing). Sintered bushing require a smooth shaft and are limited in radial load performance. Under light loads they are capable of producing a fluid bearing type performance. In order to get high radial load capability they need to be pressure fed  oil at which point they become a babbot style bearing like those used in main bearings in a gas engine. The sintered bearings resist corrosion as they are saturated with oil. One issue with bushings is they do wear and can wear unevenly. When they wear the shaft begins to move radially even though they still have low friction. In a spool bearing this can cause the spool to rub.

Ball bearings provide low friction by changing sliding motion into a rolling motion (just like when man invented the wheel). The friction losses come from sliding friction on the ball cage (the part that holds the balls evenly spaced) and sliding friction between the balls and the edge of the races (this occurs only when there is a axial load present). Ideally the ball bearing is near perfect but only if the surfaces and the shapes are perfect on the bearing. Other losses include inertial losses when the bearing changes speeds and losses that occur from bumps ( like running over a smooth road vs speed bumps and produces sound and heat). Ball bearings excel in supporting large radial loads but do not provide for axial and radial motion at the same time like bushing is capable of. Most lever drag designs use the inner bore as a bushing for axial motion (this works but is of low performance). Ball bearings also are susceptible to particle contamination (dirt, salt, rust etc.) that will severely impact it's performance.


Bushings work very well in light high speed load applications and where low maintenance is important. they will also work well in low speed applications with larger side loads if the bearing is made long. I like to see bushings on the main gear shaft and handle knobs as well as in low maintenance spool shaft bearings.
Ball bearing work better in high performance medium to high drag capable reels for supporting the spool but will require maitinance to perform well over time.

Jim N.
 

[Irish Jigger]

Penn had it right in the biginning. Bushings will last forever and they only get smoother with usage, no worries with friction there.

x2 Agree there Sal.
Never had a problem with bushed Penn 3/0 Special Senators until the Chinese put ball bearings in them. 
They now rust just like their big brothers.

[Makule]

After putting more thought into this question, I did recall having some old Penn reels that had bushings worn enough to be visibly out-of-round.  These were not small reels, but like 12/0 and 14/0 sizes, and used under severe drag settings with very large tuna.  Whether lack of maintenance were factors in these cases, I don't know.  There were also some old Pfleuger Templar reels that had bushings so worn that the spools would badly vibrate on the cast.  These were maintained but saw a great deal of use.

I started converting one of the old Templars to BB because the bushing was so worn, and because reels with BB did cast much better (longer casts) than those with bushings if the right lube was used.  It also became clear that under high loads, BB had less friction than bushings (it seemed the lube would literally be squeezed out between the bushing and the shaft and there would be metal to metal contact).  With bushings some "drag" could be felt while with BB that "drag" wasn't noticed.

The fact remains that with either, bushing or BB, lack of maintenance and/or using improper lubricants will damage both while degrading performance in the process.  Jim N's description of how sintered bronze bushings provide a fluid bearing surface explains why it may be superior for light loads.  His discussion also points out why BB function better under high load conditions.

[redsetta]

Thanks Jim - that's a great breakdown.
Much appreciated.
Cheers, Justin

[Nuvole]

Thanks Jim for the explanation.

I've 3 abu 6500 ct, two from the 80's and one custom made.
The 80's ones with bushing always seems to cast a bit further, but in my mind its difficult to accept the fact that some cheap brass bushing is better than bearings.