WoodNet Forums: Re: Anybody want to build a UniSaw?

Well thanks for the kind words here and for all the emails (and even work) I have gotten from many of you. Thanks much.

I had an arbor bracket painted black and ready to go with pics before my trip, but I had a customer who needed one ASAP so I moved it down the line. Customer needs kept me pretty busy this past week and a half, including another arbor bracket rebuild that I shipped to Blankman today. With his permission (Thank You) I decided to kill two birds with one stone and take pictures of his rebuild for this thread.

Here We Go

That's a pretty sad looking bracket you sent me to rebuild, Blankman. The steel parts are pretty rusty, but we can save those. Unfortuneately the arbor bracket has been broken. See the gold color brazed repair. The pointed tip of the bracket has been broken off, was repaired at some point and then failed again.

This is a common place for this bracket to be broken. This tip of the bracket travels parrallel to the blade (obviously). When the saw is in the blade lowered position this tip is protruding through a slot in the front trunnion bracket. Attempting to remove the arbor bracket without having the saw in the furthermost UP position, can result in this break.

Another mistake folks make is that of removing the belts and assuming that the arbor bracket no longer has motor weight on it. This is not the case as they are both suspended on the same mounting shaft and still move together. Consequently, people will sometimes get the arbor bracket driven off it's mounting shaft only to have the motor come swinging down with some force, or forcing the arbor bracket forward into the cabinet body when it is halfway off.

Back to sad, but saveable. See how bad some of the parts were.

This is the retaining nut, rusted all the way down on both sides, but some time with the wire wheel and we can get it back on track.

Anyway . . . We have an Arbor Bracket painted and nearly ready

When we install the actual bracket that we are going to use, it will be black. But for this customer, we shipped a grey bracket. After removing the masking, there can still be some overspray. In particular I want to make one more pass to make sure that bearing seats are clean and ready to go.

I'm using a steel brush in this picture. I do NOT recommend this, it just happens to be the only one I had left that is small enough to clean these openings. As in sandblasting, we do not want to wear these ports out. Doing so increases the chance that we could more easily "spin" a bearing out.

One of the things I do often times, because I can, is throw the arbor in the lathe and check it. This arbor reads .0055 run out on the flange which is just over what I consider to be the specification range. If you want to discuss that number there are plenty of threads currently for you to discuss that topic.

Because this was a customer's arbor I dressed it on the lathe. For you at home, leave it alone for the time being, we are going to dress it later using some sandpaper, a block of of wood and your fence.

With the bracket cleaned up, the other parts already done, and the bearings with proper spacers on hand we should have everything we need.

Let's get the first bearing on the arbor. Start it by hand. The outside dimensions of the fine threads on the arbor tail should allow the press fit bearing to pass by more easily.

We can start it in the press. Sometimes if the starting position feels loose enough I will use a soft mallet to do this. The two things that I'm concentrating on here are:

1. Not bunging the threads up

and

2. Supporting the bearing inner raceway for the press operation.

Note in the picture above that as soon as the arbor begins to pass through the bearing and I can get support under the inner raceway of the bearing I do. But I wait until the threads have passed by so I don't inadvertently cleave off the tops of them.

I want to support the raceway so that I don't accidentally shear the bearing if it comes to a tight spot on the arbor.

Once the bearing is pressed up to the arbor flange, then the spacer and spring washer can be placed on it and set aside.

Let's get the other bearing in place.

Start it by hand and push hard with both your thumbs. You want this to be tight, so it doesn't spin out. If you think it's too loose, but you still want to proceed, try a few drops of the red or high strength loctite on the outer rim of the bearng.

This one is okay without that step.

If necessary I would move to the press to finish seating the bearing. BE CAREFULL. If this operation requires using a hydraulic press then you MUST support the casting properly to avoid snapping it off.

In this case we can seat the bearing by gently striking it with a soft mallet.

I'm not sure how long a thread I can post here so take a coffee break and we'll start a new post.

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I may be wierd now, but I'm saving to be eccentric.

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