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View Full Version : Biax 7/EL weird bearing and what I can replace it with (or is this still being made)



rmuell01
02-16-2013, 11:46 PM
this is my biax bearing and the balls escape from the retainer from time to time. Lots of gnashing with loud noises.
I did try to crimp the retainer but they continue to drop out.

http://i178.photobucket.com/albums/w243/rmuell01/20130215_153426_zpsfe961a5f.jpg

I know that Dapra/Biax does not have these for sale so I have to go to the open market.

I don't know how to describe it to do a search. any one familiar with this?

the armature has a bearing on each end.

this is a later biax that has the more common bearings (I 'borrowed' this pic from one of users on this board - thanks!)

http://i178.photobucket.com/albums/w243/rmuell01/Biaxfrontoff4_zps433b4e60.jpg

Rob

Richard King
02-17-2013, 12:31 AM
Rob if I were you I would take the motor to a small electric tool repair shop and have them repair it for you. That little plastic fan breaks so easily. That bearing is a standard size I believe. You can also call Ed Dyjak. He has been repairing those scrapers for years. He is a neighbor of yours in Milford MI. 248-684-4260. He is a DAPRA Distributor and used to be a repair station. Tell him I said hello.

EVguru
02-17-2013, 09:12 AM
Looks like a magneto bearing to me.

John Stevenson
02-17-2013, 09:39 AM
Yes definitely a magneto bearing which in fact is a low cost angular contact bearing.

Unfortunately these come in sizes that are not covered by easily obtainable normal deep groove bearings.

the scraper with the normal bearing more than likely has different bearing diameters.
An E6 is 6mm bore, 21mm OD and 7 wide
An E8 is 8mm bore 24mm OD and 7 wide
An E10 is 10mm bore 28mm OD and 8 wide.

rmuell01
02-17-2013, 02:47 PM
Rich, I'll contact Ed to see if he has these 'magneto bearings'

John and EVGuru, thanks for giving me the correct term. Searching on 'magneto' also showed that mcgyver had a post about these.

rmuell01
02-18-2013, 04:33 PM
Rich, I talked with Ed but no Joy on anything for my scraper.

Mcgyver
02-18-2013, 04:40 PM
John and EVGuru, thanks for giving me the correct term. Searching on 'magneto' also showed that mcgyver had a post about these.

they are still available, there's a place in the US, RC bearings or something like that that distributes them. they are one of those miserable organziations that insist you buy through their distributor who quadruples the price, or at least the canuck one does, so i've put it on the back burner. anyway point is you can get, keep googling :D

Richard King
02-18-2013, 05:36 PM
I would replace them with a regular ball bearing then. Maybe a double row sealed bearing. Measure the OD and ID and length and call a local bearing house or Bearings Inc in Chicago

TGTool
02-18-2013, 06:16 PM
Rob,
The last I heard Motion Industries still supplied them but it carried a different number system and I can't remember it. I've got a sheet of the crossover numbers used by different manufacturers for magneto bearings. What's the ID, OD and width of the existing one? Maybe one of these numbers will ring a bell with one of the suppliers.

rmuell01
02-18-2013, 08:43 PM
Rob,
The last I heard Motion Industries still supplied them but it carried a different number system and I can't remember it. I've got a sheet of the crossover numbers used by different manufacturers for magneto bearings. What's the ID, OD and width of the existing one? Maybe one of these numbers will ring a bell with one of the suppliers.

the measurements I took are 11.4mm x 18.4mm x 5.6mm (in/out/width) . mind you, I took this from the exploded bearing. and the shaft in the scraper.
When I get back from traveling this week, I'll take the good one to applied bearing.

rmuell01
02-18-2013, 08:50 PM
I would replace them with a regular ball bearing then. Maybe a double row sealed bearing. Measure the OD and ID and length and call a local bearing house or Bearings Inc in Chicago

I'm toying with that idea Rich, but the bearing retainers are molded (?) into the scraper.

the groove in the shaft is where the bearing goes which mates to a depression in the upper body of the scraper.

http://i178.photobucket.com/albums/w243/rmuell01/20130215_153412_zpsce52558a.jpg

John Stevenson
02-18-2013, 09:16 PM
No way, that's a loose inner.
To make it like that would be loads of work.
I did say in post #4 that magneto bearings do not have a readily available deep grooved replacement so you are probably stuck with them.
However a set of new bearing will probably outlast the life of the tool.

Tomorrow I'll find a tool I made many years ago for extracting the inner race, just like the one in the picture from magneto's, and post a picture.
These had the very delicate Bakelite slip ring behind the bearing so prising off was not an option.

If you get really stuck these people will post to the US.

http://www.arceurotrade.co.uk/Catalogue/Bearings/Angular-Contact-Ball-Bearings

TGTool
02-18-2013, 10:00 PM
Now I'm puzzled about the "magneto bearing" designation too. It ought to have a low shoulder on one side (angular contact) and the photo looks like a regular bearing inner. And if the dimensions are fractional metrics it wouldn't be a standard ball bearing either which should be based on metric numbers. Although, were you measuring the ID as the inside diameter of the ball race?

John Stevenson
02-19-2013, 05:04 AM
Magneto bearing have a full inner grove as in the pic, can actually go on either way. Cage and balls snap round the inner and the outer has the low shoulder on one side, far more open than an angular contact so the outer can only go on one way for the thrust to work.

Standard sizes are posted in post # 4 and the link in post #12

However there is an E12, E13,E15 and E20 not on that list.

Again none have a direct comparison to normal deep groove bearings because they are usually a lot thinner even if like the E12 there is a bearing with the same ID and OD.

Come on guys it's not rocket science, the question has been answerd

It's a magneto bearing just buy two new bearing - end of story.

EVguru
02-19-2013, 09:31 AM
Now I'm puzzled about the "magneto bearing" designation too. It ought to have a low shoulder on one side (angular contact) and the photo looks like a regular bearing inner.

The shoulder is entirely in the outer race. The inner race and ball cage simply fall out of the outer race unlike a conventional angular contact bearing.

TGTool
02-19-2013, 01:22 PM
Magneto bearing have a full inner grove as in the pic, can actually go on either way. Cage and balls snap round the inner and the outer has the low shoulder on one side, far more open than an angular contact so the outer can only go on one way for the thrust to work.



The shoulder is entirely in the outer race. The inner race and ball cage simply fall out of the outer race unlike a conventional angular contact bearing.

Great! You learn something on this board every day. I've taken them apart, put them together, heard about them, but that particular aspect just never settled in. Thanks.

Rich Carlstedt
02-19-2013, 08:43 PM
the measurements I took are 11.4mm x 18.4mm x 5.6mm (in/out/width) . mind you, I took this from the exploded bearing. and the shaft in the scraper.
.

This can't be right
You only show a 7 mm difference between ID and OD
Magneto Bearings ( e series) have at least 12 mm to account for both races and the balls !

Rich

rmuell01
02-19-2013, 09:37 PM
This can't be right
You only show a 7 mm difference between ID and OD
Magneto Bearings ( e series) have at least 12 mm to account for both races and the balls !

Rich

Rich, you may be correct. I have zero experience measuring this type bearing. here are my hand written notes.

http://i178.photobucket.com/albums/w243/rmuell01/20130219_203308_zpsfd645fe2.jpg

I was also in a hurry.

rmuell01
02-19-2013, 09:44 PM
just so we're all on the same page. the following scraper pic is not mine, but a later model that shows dapra did away with the magneto bearings.

http://i178.photobucket.com/albums/w243/rmuell01/Biaxfrontoff4_zps433b4e60.jpg (http://i178.photobucket.com/albums/w243/rmuell01/20130215_153426_zpsfe961a5f.jpg)

Rich Carlstedt
02-19-2013, 09:51 PM
My guess from your sketch is you have a E8
which has a of Bore 8 mm -OD of24mm and width of 7mm

Possible it is a a E 8-7
Which has Bore of 7 mm , but the same OD and width as the E 8
Just my guess

Rich

rmuell01
02-26-2013, 12:35 PM
An update on the magneto bearings.

I took the biax further apart, down to the gears. I noticed that the big helical gear was metal and not fiber. It's one of the reasons I tore it down in the first place, wanted to get the measurements. I don't know if all 4/EASL models are the same, but I thin I'm in good shape for now. no need to find one or get one made.

I decided to clean it all up and attempt to put it together. At this point I have two fewer ball bearings than the required 8. This particular Biax had always made a growling noise so I figured the bearings weren't seating correctly.

That's when I noticed the plastic fan had been jammed down away from the bearings making the pinion a little out of position. I snugged it up close to the bearings and reassembled the scraper.

Now putting the case together for the biax has always been a trial. it's got an outer tube that has threads at both ends (different threads) with about 2 inches in the center w/o threads. This is used to attach the bottom and top of the scraper. It also has a small detent and keyway to align the two halves. With the collar screwed all the way to the bottom, you still can't fit the top into the detent because the collar is in the way. So I worked at it until it was almost to tight and I rotated the top into the keyway. Tightened the the collar a bit and it was done.

I don't think the scraper was aligned correctly or tight enough and there was room for the bearing to move about.

I turned the scraper on and it sounds great (meaning no more growling), and this is on 6 of 8 bearings. I used it for a few hours with no noticeable increase of noise.

I'm ordering the 3 different magneto bearings (really? they couldn't use one size?) in the scraper and will replace them as they arrive.

On the bearings, I still don't know the exact sizes as Applied bearing (in my area) doesn't have any in stock. so I'm ordering a number of them and will return the rest.

Also per the bearings, there are bearing races installed in the biax that I couldn't remove (I didn't try that hard) so that would alter the sizes I quoted previously.

TGTool
02-26-2013, 04:18 PM
Do keep us posted with what you find works and the bearings the tool actually uses. Other owners are dying to know.

rmuell01
02-26-2013, 05:14 PM
Do keep us posted with what you find works and the bearings the tool actually uses. Other owners are dying to know.

will do.

Robo
02-26-2013, 07:45 PM
"On the bearings, I still don't know the exact sizes as Applied bearing (in my area) doesn't have any in stock."

Not sure where in Michigan your at but boy do we miss Detroit Ball Bearing......Applied bought them and closed the branch near me shortly after buying them. Detroit Ball was FANTASTIC!!

John Stevenson
02-26-2013, 08:36 PM
On the bearings, I still don't know the exact sizes as Applied bearing (in my area) doesn't have any in stock. so I'm ordering a number of them and will return the rest.



I don't understand this statement as whether they have them in stock or not a bearing book will tell you which ones they are.
All you need do is measure ID, OD and width.
I even stated some of the popular ones in an earlier post.

.RC.
02-26-2013, 09:02 PM
I don't understand this statement as whether they have them in stock or not a bearing book will tell you which ones they are.
All you need do is measure ID, OD and width.
I even stated some of the popular ones in an earlier post.


Come on John, cut them a bit of slack here, magneto bearings are metric.... The US has not developed as far as to embrace the superior measuring system yet... :D:D

rmuell01
02-26-2013, 09:04 PM
You provided good info. I took the measurements and they don't match any of those you listed.
my 1st bearing is 10mm bore, 18mm OD and 6mm wide
the second is 10 x 24 x 6
the third is smaller yet, but I couldn't reach it to measure.

Is it possible the Magneto bearings of 30-40 years ago were sized differently ? I think the motor was made by Fein.

An E6 is 6mm bore, 21mm OD and 7 wide
An E8 is 8mm bore 24mm OD and 7 wide
An E10 is 10mm bore 28mm OD and 8 wide

.RC.
02-26-2013, 09:55 PM
You provided good info. I took the measurements and they don't match any of those you listed.
my 1st bearing is 10mm bore, 18mm OD and 6mm wide
the second is 10 x 24 x 6
the third is smaller yet, but I couldn't reach it to measure.



ahh now we have something to work with....

A search finds very little in the way of those sizes except that there are options involving modifying the set up..

10X18X6 could be replaced by a 10X18X4 with a 2mm spacer made. or go for a 10 19 5 and bore the housing..

10X24X6 could be replaced by a 6901 12X24X6 with a bush made for the ID..

EVguru
02-27-2013, 05:18 AM
How are you measuring the bearing OD if you haven't removed the races from the case? Are you able to get a measuring tool in deep enough?

rmuell01
02-28-2013, 07:41 PM
Tomorrow I'll find a tool I made many years ago for extracting the inner race, just like the one in the picture from magneto's, and post a picture.
These had the very delicate Bakelite slip ring behind the bearing so prising off was not an option.

If you get really stuck these people will post to the US.

http://www.arceurotrade.co.uk/Catalogue/Bearings/Angular-Contact-Ball-Bearings

Thanks for the link John. I did place an order with them. 3 bearings w/delivery - $46. pretty good.

darryl
02-28-2013, 08:01 PM
Just a thought- you said the ball cage and races just come apart when the motor is disassembled. That tells me they are angular contact- not that this means much anyway. I have some like that, smaller than what you need, but that's how these work anyway. I'm sure some angular contact bearings don't come apart, but it's just the particular design. Not a good thing nor a bad thing- but good in the sense that they would be easier to clean and re-lube.

Have I missed reading some of the details given regarding angular contact bearings in general- in particular, are they made to a higher abec rating or to a higher standard of runout?

rmuell01
02-28-2013, 09:27 PM
How are you measuring the bearing OD if you haven't removed the races from the case? Are you able to get a measuring tool in deep enough?

Sorry EV - I didn't answer your post.
the races are stuck but two of them I could measure, kinda.

I ordered E5-E6 and E8. but it'll be awhile until I get them. I'll update if they are correct for this biax.

rmuell01
02-28-2013, 09:29 PM
Just a thought- you said the ball cage and races just come apart when the motor is disassembled. That tells me they are angular contact- .....

Have I missed reading some of the details given regarding angular contact bearings in general- in particular, are they made to a higher abec rating or to a higher standard of runout?

As John says, they are a lower cost angular type.