Bearing spacers for 320/520/521

[mklotz70]

I've been talking about making these for awhile now and I finally got some done. Anyone that has read up on the disc brake threads for the 521's probably knows that the stock inner bearing is NLA. The 320's and 520's use the same unavailable inner bearing. I have previously posted that the 620 drum bearing is readily available and will work if a 2mm(approx) spacer is used. The problem was that there were no spacers available. Well, here they are.

 

 

The DRO on the lathe sure made it a lot easier to make duplicates. Are they perfect? No. Do they need to be? No. They are withing a couple of thousandths of each other and for what they are doing, 10-20 thou wouldn't matter. It just wasn't worth the setup cost to have them CNC'd for the small amount that will be sold.

 

 

This is the 521 spindle with the collar and NLA bearing (32KB02).

 

 

This is the collar. It can be removed by breaking it loose with a pipe wrench or carefully using a hammer and chisel tapping between the boss and the collar. The wheel seal rides on this surface, so if you think you might use it again, remove it in such a way as to not damage the surface.

 

 

With the collar removed, the "cup" of the spacer will register over the boss at the base of the spindle.

 

 

With the 620 drum bearing (Set A24) on the spacer, you can see that the race is at the same distance from the spindle....which means the hub will be right back where it started.

 

 

Just a closer look.

 

 

 

To use this spacer, you will have to modify the backing plate just a bit. The hole in the backing plate fits the boss at the base of the spindle. It will have to be opened up to allow the spacer to sit down over the boss. The backing plate comes almost up even with the boss, so there would not be any way to register the spacer if it did not have the "cup" on the backside. The radius at the base of the spindle stopped me from registering the spacer to the spindle itself. If you don't want to modify the backing plate, good luck finding stock bearings. :)

 

For those of you running Beebani's disc bracket, you'll have to check to see if the center hole is big enough to clear the spacer. You may need to open up the center hole. The spacer is approx. 2.4" OD. Using the stock, NLA, bearing is the only downfall to his and Fineline's setups. That's no longer a problem. :)

 

 

 

 

Place the spacer over the spindle to mark how much needs to be removed.

 

 

Mark the backing plate.

 

 

It's only about an 1/8".

 

 

I used a die grinder and a carbide bit. It took about 5 min and that included cleaning up the edges with a file.

 

 

It doesn't have to be perfect, no one will ever see it! I could have put it in the mill and got it perfect, but I wanted to show it in a way that most guys could duplicate.

 

 

The hub clears the spacer just fine.

 

 

I guess the big question now is price. Thanks to the DRO, I was able to make them fast enough to keep the price pretty reasonable. At least, I think so.

 

They will cost $20 for a pair plus $2.00 for 1st class shipping. Paypal is definitely preferred, but Postal Money Orders would work too. PM me for email or mailing address.

 

You should be able to buy the bearings locally or online at any of the typical sites. You will want bearings for a '74 620. Yes, the year ranges from '72.5 to late '77 or so, but let's keep this simple. :)

[mklotz70]

Okay...now that the big post is out of the way.....

 

I have 11 sets made up right now. A few of them are already spoken for, but I have material to make more. I think I have enough to make about 20 more sets. I didn't want to get carried away until I found out how much interest there was.

 

 

Here's the deal......I have not put any of these prototypes on a vehicle yet. They check out just fine on the bench and there's no reason to think there will be any problems in actual use. It simply spaces the bearing away from the boss. It doesn't bear any load or vehicle weight. There's no reason for it to spin unless your bearing race starts spinning on your spindle.

 

So....the first two guys to get them mounted on their rig and post pics(in this thread or sent to me directly) of them on the spindles, with the backing plate in place will get their money returned to them....including shipping. There's no way to know or predict who will actually put them on first, so this is the only way I can think of to give away free ones.

[fisch]

I have no idea if and when i might need these but man I can breath a little better knowing they are out there. M, you rock and are a saint for doing this for the community.

[BEEBANI]

Mike, once you know for sure there are no problems, you should post these on ebay, a lot of my bracket customers are on there. There are a ton of 521's in the cali area who would definitely need these. Many of them haven't came to this forum like I've urged them to and may not see these any other way.

 

If that's too much hassle, then I'll link this post to each guy I sell to.

[mklotz70]

Bee....that's pretty much what I was thinking....hence trying to give some incentive for some guys to put some on soon :)

 

Looking at the pics of your brackets, I'm not sure they'll fit in the middle hole. What's the diameter of that hole.....I might be able to trim my OD down to lessen how much needs to be clearanced. I probably can't take much off since I chuck the spacer by the inside of the cup to finish the outside....don't want it to warp.

[mklotz70]

Fisch.....thanks. I'll try to make enough to have some on the shelf, but if they run out, there's no guarantee I'll be around down the road to make more. I'm sure you're pretty safe for the next couple of months :)

[slodat]

Big congrats Mike! This is something you have been wanting to get out the door for a while now. Looks good!!

[mklotz70]

I just got back from Office Depot and the PO. OD had a clearance sale on 6x9 bubble wrap envelopes and the PO wanted less than I thought for the 48 states....so it comes to a whopping $2 for shipping. I already edited the posting above, but most people won't go back and reread that.

 

Thanks Slodat. Looks like you'll get some nice arms from Bee a lot sooner than I could have done them. :)

[dat521gatherer]

mike you are a pillar of creation. i'll pm you soon.