Arbor not aligned to guide holder

[markm]

I've had a BT3000 that I bought off craigslist for a couple years now. It's been serving me pretty well.

I have an issue, though. The splitter was missing when I bought it, so I bought one off a parts store. When I went to install it, the splitter didn't line up with the blade. I think this is because the arbor is out of alignment with the guide holder. From the perspective of someone standing at the table saw as if they're using it, the rear of the blade is pretty far over to the right, so it doesn't line up with the part of the guide holder that the splitter is bolted against. There are some shims where the splitter is installed that would help if I had the opposite problem, but nothing to help with my problem.

For a while, I went with the easy solution, which was to shim the blade to the left with a couple arbor shims that add up to ~30 thousandths (in addition to the .5" and .25" arbor shims). This isn't an ideal solution, because it reduces the amount of unthreaded arbor for the blade to seat on, but there is still enough and it has worked okay-ish.

However, I'd like to fix it. Having the blade that far out of alignment means that the miter slot table would need to be that far out of alignment, and I'd just as soon have the miter slot table register against the the saw table without any fuss. Has anyone else had this issue and fixed it?

[LCHIEN]

First of all, welcome to the forum. I approved your post.

Second,you might look in the BT3x00 discussion on this site and download by BT3 FAQ from one of the first posts of appropriate name.

Third, to address your problem, my first suggestion is that the splitters are soft steel and can be "persuaded" to lean right or left by just bending it slightly.
The first order of business is to stare down the blade and the splitter and make sure that the splitter is parallel to the blade and perfectly upright, by what ever means of persuasion you can use.
After that, aligning the splitter with shims in the guide holder bracket or whatever its called is next.
But many people have been folloed by what they thought was a splitter too far to one side or the other but really what they had was one slightly bent.

It is really necessary to get the splitter and shims lined up behind the blade and then worry about the splitter being vertical.

Oh, and maybe this is a stupid question but in addition to the .25 and .5" spacers on the arbor, you have the two arbor washers for each side of the blade, no?

Check those and get back to me.

[markm]

The splitter is vertical (when the blade is vertical), so a bent splitter is not the problem. I've taken out all the splitter shims and the blade is still too far to the right, thus I need the arbor shims.

However, the splitter is not inline with the blade, because the surface the splitter is bolted to is not inline with the blade. I put a straightedge against the blade and splitter and measured the gaps with feeler gauges. Here's the result: https://www.dropbox.com/s/ktefe96coz..._2197.JPG?dl=0

And yes, in addition to the .25" and .5" spacers (and the two additional spacers for .03"), I have the two arbor washers.

[capncarl]

Has the motor shifted?

[LCHIEN]

Well, I have not heard of such a thing. I believe the motor mounts to the back side of the locker bracket (the piece that goes up and down riding on the shims) and the splitter bracket is part of the locker bracket so unless the arbor was assembled with the bearings slightly off then I don't see how it couldn't fit.
Potentially you could put shims between the motor and the locker bracket to set the arbor tot he right and even correct non-parallelism of the blade/splitter system. But I have never heard of anyone having to do that.

[leehljp]

Is the splitter flat, or has it been checked for "flat", (i.e. not warped marginally)?

[markm]

capncarl, I'm not sure how to check if the motor has shifter, but nothing looks out of place... just a little misaligned. Hank, the splitter is flat.

I think it's okay if the motor is misaligned because the belt can make up for that. I'm guessing that either the arbor bearing was put in a little misaligned (or was bumped off alignment at some point), or that the splitter bracket was bent at some point.

When ripping, I've noticed the tendency for the splitter to pull the wood away from the fence, which makes me nervous about safety. Maybe I ought to start ripping with the fence on the other side of the blade.

[JimD]

My saw is a BT3100 and has shims on both sides of the splitter. It came that way. I thus think it is normal to have to shim the splitter away from the casting towards the clamping nuts.

[mpc]

What JimD posted about his splitter plate shims is how they should work - there should be shims between the casting boss and the splitter itself to make the adjustment. The remaining shims can either be stored in a jar somewhere or on the nut-side of the splitter.

The OP's issue sounds like a bent/damaged casting assembly or the arbor support bearing isn't properly seated in the aluminum casting parts. I'd take the splitter out completely and carefully examine the casting for any signs a prior owner tried to adjust it by filing it or something similar. It'd be easy to screw up the parallelism that way. Then check the arbor & its support bearing... A bit of sawdust could have been trapped between the bearing and casting the last time the saw was dis-assembled for example so the bearing is "tilted" in its mounting hole in the casting. That bearing can be a bit of a tight fit into the casting anyway - not quite a true "press fit" - but pretty snug so it'll get cockeyed and jam if it wasn't inserted & driven perfectly flat last time it was re-assembled. If the bearing is worn out then the arbor will have slop/free-play and that can manifest itself as a cockeyed blade too because the drive belts will pull the arbor shaft to some abnormal angle. With the saw unplugged, raise the blade and firmly hold it. Try to firmly move it left-right, up-down, etc. If there is any "clicking" sound, or any motion, then I'd suspect the arbor support bearing is kaput.

Then, take off the right side panel so you can see and reach the motor body. With the blade height set to about mid-travel, grab the back of the motor and try lifting moving it left-right (towards the front and back panels of the saw body). If it moves much, the motor is possibly loose on the aluminum casting pieces or more likely the shim adjustment setscrews are too loose. This shouldn't be the OP's problem because the arbor and splitter mount to the same casting - loose shims shouldn't affect that alignment I don't think... but this test can identify other factors that indicate an improperly adjusted/improperly assembled saw.

One thing I noted in the OP's original post: the sliding miter table (aka SMT) and the side/edge of the saw's top surface don't necessarily align. On the BT3, the body of the saw blade is the master reference item for all other adjustments (SMT travel path, miter fence, rip fence, etc.) since the blade parallelism angle relative to the tabletop can NOT be adjusted on BT3s like they can on almost all other saws. You adjust the SMT mounting clamps and table so the SMT table itself slides perfectly parallel to the face of the blade... and there should always be a small gap between the SMT table and the saw's top/edge. That gap may differ at the front of the saw compared to the gap at the back of the saw too. On most BT3s it will differ in fact... it's only by sheer luck when they happen to be perfectly matched on a particular BT3. You'll also discover the SMT table surface is slightly HIGHER than the top surface of the main saw body. That way any workpiece on the SMT moves above, instead of drags along, the top of the saw body.

mpc