Drill Press Table Not Square to Bit

reible · Post by **reible** » Thu Aug 07, 2014 1:28 pm

Dusty I think you are getting in to a worse situation by shimming the table.

We have had discussions before on what happens when this is done, I will not go into that.

You are far better off using piece of mdf on the table top and shimming that to your satisfaction.

I didn't check the math but assuming it was done correctly you are not off by much. So the next decision can be based on what the hole is used for. If it is for a bolt to go through, or the likes then simply drill a hole that is slightly larger, as one example. This is what is most often done, a clearance hole for 1/4" bolt is a letter "F" drill.

Ed

Gene Howe · Post by **Gene Howe** » Thu Aug 07, 2014 6:16 pm

That is essentially how I handled it. May have gone a bit farther with the added fence and stop block, though.

reible wrote:Dusty I think you are getting in to a worse situation by shimming the table.

We have had discussions before on what happens when this is done, I will not go into that.

You are far better off using piece of mdf on the table top and shimming that to your satisfaction.

I didn't check the math but assuming it was done correctly you are not off by much. So the next decision can be based on what the hole is used for. If it is for a bolt to go through, or the likes then simply drill a hole that is slightly larger, as one example. This is what is most often done, a clearance hole for 1/4" bolt is a letter "F" drill.

Ed

dusty · Post by **dusty** » Thu Aug 07, 2014 6:36 pm

reible wrote:Dusty I think you are getting in to a worse situation by shimming the table.

We have had discussions before on what happens when this is done, I will not go into that.

You are far better off using piece of mdf on the table top and shimming that to your satisfaction.

I didn't check the math but assuming it was done correctly you are not off by much. So the next decision can be based on what the hole is used for. If it is for a bolt to go through, or the likes then simply drill a hole that is slightly larger, as one example. This is what is most often done, a clearance hole for 1/4" bolt is a letter "F" drill.

Ed

Thank you for the warning and recommendation. I know the table is not flat. In fact I have three tables that are all somewhat non-flat. One has a high corner, one has a low spot in the middle and then this one. All are very serviceable for nearly all operations.

I'll not pursue this here on the forum. I can see that the consensus is not in favor of a long discussion about my table top.

"Wild Bad Bob" · Post by **"Wild Bad Bob"** » Thu Aug 07, 2014 9:10 pm

My question, thought was this morning, WTF are trying to do that needs that accuracy??

skou · Post by **skou** » Fri Aug 08, 2014 4:07 am

Especially with wood?

Bob, he's trying to hone out the holes on a 2000 HP dragster bellhousing. (Maybe.)

That is some precision stuff. (Dusty, you should have a Model 10 for this.

)
steve

dusty · Post by **dusty** » Fri Aug 08, 2014 7:47 am

rbursek wrote:My question, thought was this morning, WTF are trying to do that needs that accuracy??

What are you trying to do?

Drill holes in multiple pieces that all line up when I'm done!

The original question was how much error will my .3° out-of-alignment table create. How accurate do the holes have to be to line up?

If close enough for Government work is the answer then I don't even need a drill press. I can do that with a hand drill. Just move the pieces around until the holes are "close" and tap the bolt through with a hammer if they are not perfect.

Ed in Tampa · Post by **Ed in Tampa** » Fri Aug 08, 2014 9:37 am

Actually I am interested. My first question is why is shimming not a good idea? I don't recall the discussion on the topic.

And secondly I wonder why the tables don't come from Shopsmith flat to start with. I would think the surface was ground after casting and I would think it would be perfectly flat. Although I do know I received two tables that were not flat. I complained on both and they finally sent me a flat one.

On the drill press issue I thought you (dusty) was the one that came up with a coat hanger idea where we bent coat hanger wire into a z and chucked one end into the drill chuck and used the other end at a indicator to show and high or low spots on the table as we turned the chuck by hand.

I leveled my table that way and it worked like a charm.

"Wild Bad Bob" · Post by **"Wild Bad Bob"** » Fri Aug 08, 2014 9:46 am

Dusty, see your point if matching something up, dowel joint, ect.

dusty · Post by **dusty** » Sat Aug 09, 2014 8:33 am

I am still working on the initial question in this thread but one of my searches brought me to this thread(again). Many will find it just so much about nothing but I found it very interesting and helpful too better understand the dynamics of Main Table Alignment.

algale · Post by **algale** » Sat Aug 09, 2014 10:41 am

Ed in Tampa wrote:Actually I am interested. My first question is why is shimming not a good idea? I don't recall the discussion on the topic.

And secondly I wonder why the tables don't come from Shopsmith flat to start with. I would think the surface was ground after casting and I would think it would be perfectly flat. Although I do know I received two tables that were not flat. I complained on both and they finally sent me a flat one.

On the drill press issue I thought you (dusty) was the one that came up with a coat hanger idea where we bent coat hanger wire into a z and chucked one end into the drill chuck and used the other end at a indicator to show and high or low spots on the table as we turned the chuck by hand.

I leveled my table that way and it worked like a charm.

I think the answer is blade-heel (maybe we should call it table-heel since it is the table that tilts on the Shopsmith rather than the blade). When the table is shimmed to be perfectly level in drill press mode, there is heeling when the table is tilted in table saw mode.