Question about table saw alignment

[woodhead52]

The newbie here. Here's the background. I set out yesterday to do all of my main alignments using the Dial Indicator Gage I purchased from Shopsmith and my Nick Engler Critical Alignment DVD from Shopsmith.

For clarity I have the older non magnetic strip 520 Pro Fence system.

I feel very good about all of my alignments except that of the aligning the Saw blade (axis of rotation) to the main table, so I'm looking for advice. Try as I might the best I was able to achieve after several hours was 5.5 thousandths (0.0055). Is this good enough or do I need to go back to the drawing board.

On the Critical Alignment DVD Nick is able within the 20 minute plus video to align the rotation axis to the table to 0.0015, side to side. Not for lack of trying, I never got close to that. I followed his instructions to letter, many times, , but couldn't get it done.

Somethings I did discover while doing the alignment for which I see no work around are this. Two problems really. First while the front trundle (in feed side) has slightly over sized bolt holes for wiggle room, the rear trundle (out feed side) does not. Both holes are just large enough for the bolts to slip through allowing next to no wiggle room. Secondly, there is a table railing nut directly up against the Headstock side of the rear trundle which further restricts movement on that side.

Yesterday I only used Nick's way, loosening all of the trundle bolts then snugging the rear right (opposite the Headstock) to act as the pivot. This morning I awoke wondering if maybe I should try again but snugging rear left bolt (headstock side) instead since this is where the railing nut interferes with the trundle anyway.

Or, should I quit while I'm ahead?

Pete

[algale]

I think .005 is acceptable. As to the trunnion bolt holes, this has been discussed before. Shopsmith'a position is that this is a manufacturing defect and if you call them they will authorize a return and redrill the smaller holes to match the larger. Alternatively, several of us have done the fix ourselves. I can verify that alignment got much easier for me after I redrilled my trunnion.

As to the railing nut interference, I don't have a recall of any such issue on my 520.

As to which trunnion bolt to leave snug, I don't think it matters.

[beeg]

I think ya ought to get it aligned to .0001. That should drive ya CRAZY.


Now in reality, .0055 should be okay. It'll get easier for each alignment ya do in the future.

[woodhead52]

... Alternatively, several of us have done the fix ourselves. I can verify that alignment got much easier for me after I redrilled my trunnion.

As to the railing nut interference, I don't have a recall of any such issue on my 520.

As to which trunnion bolt to leave snug, I don't think it matters.

Please share with me what I need to do to enlarge the holes myself I've heard it takes SS two weeks just to send me an order, not sure I want to wait for something like this.

Thanks Pete,

Here are pictures of the railing bolt/nut issue.

[ATTACH]23281[/ATTACH]

[ATTACH]23282[/ATTACH]

[ATTACH]23283[/ATTACH]

[dusty]

The newbie here. Here's the background. I set out yesterday to do all of my main alignments using the Dial Indicator Gage I purchased from Shopsmith and my Nick Engler Critical Alignment DVD from Shopsmith.

For clarity I have the older non magnetic strip 520 Pro Fence system.

I feel very good about all of my alignments except that of the aligning the Saw blade (axis of rotation) to the main table, so I'm looking for advice. Try as I might the best I was able to achieve after several hours was 5.5 thousandths (0.0055). Is this good enough or do I need to go back to the drawing board.

On the Critical Alignment DVD Nick is able within the 20 minute plus video to align the rotation axis to the table to 0.0015, side to side. Not for lack of trying, I never got close to that. I followed his instructions to letter, many times, , but couldn't get it done.

Somethings I did discover while doing the alignment for which I see no work around are this. Two problems really. First while the front trundle (in feed side) has slightly over sized bolt holes for wiggle room, the rear trundle (out feed side) does not. Both holes are just large enough for the bolts to slip through allowing next to no wiggle room. Secondly, there is a table railing nut directly up against the Headstock side of the rear trundle which further restricts movement on that side.

Yesterday I only used Nick's way, loosening all of the trundle bolts then snugging the rear right (opposite the Headstock) to act as the pivot. This morning I awoke wondering if maybe I should try again but snugging rear left bolt (headstock side) instead since this is where the railing nut interferes with the trundle anyway.

Or, should I quit while I'm ahead?

Pete

If you have it aligned so that the blade is parallel to the miter slot to within .005", I would "quit". You'll not get it much better.

Since you have a trunnion that has been declared "out of spec", I would call Shopsmith and negotiate a replacement (with the defective one to be returned to them). If they will go along with that, you have no down time.

I too have a table rail nut that is very, very close to the trunnion but it does not interfere with alignment.

I have neither seen the .0015" tolerance called out (I do not have the video). Why is side to side alignment to the axis of rotation critical? It is not, in my opinion unless you are in the drill press mode and then it is not critical that the table be that precise (side to side). I may be out of order on this because I am not certain which alignment we are discussing.

[dusty]

Please share with me what I need to do to enlarge the holes myself I've heard it takes SS two weeks just to send me an order, not sure I want to wait for something like this.

Thanks Pete,

Here are pictures of the railing bolt/nut issue.

[ATTACH]23281[/ATTACH]

[ATTACH]23282[/ATTACH]

[ATTACH]23283[/ATTACH]

Just remove the two rear trunnion bolts and slip the rear trunnion off of its shaft, drill out the two holes, reinstall and align.

Be careful when drilling the holes that the trunnion does not get away from you. Unless you have two Shopsmiths or a drill press, you will likely need to drill the holes using a hand drill. That can be done; I did it with one of mine. The hole location is not critical and it has already been determined. You just need to enlarge the hole. If doing it by hand, I would suggest sneaking up on the final size.

[algale]

When I drilled mine I used the shopsmith in horizontal boring mode. Remove main table and detach offending trunnion. Place on aux tableau the right side and in front of this connect a floating table with the connector tubes (this is to bridge the gap over the carriage. Now back up the trunnion with the rip fence and some scrap wood. Line up your holes with the spindle with using a drill but that fits the existing hole exactly. Once aligned for horizontal boring, clamp trunnion down and replace bit with one sized to match holes in trunnion with larger holes and drill. Won't take much pressure.

[algale]

When I drilled mine I used the shopsmith in horizontal boring mode. Remove main table and detach offending trunnion. Place on aux table on the right side and in front of this connect a floating table with the connector tubes (this is to bridge the gap over the carriage. Now back up the trunnion with the rip fence and some scrap wood. Line up your holes with the spindle with using a drill bit that fits the existing hole exactly. Once aligned for horizontal boring, clamp trunnion down and replace bit with one sized to match holes in trunnion with larger holes and drill. Won't take much pressure.

[beeg]

You just need to enlarge the hole. If doing it by hand, I would suggest sneaking up on the final size.

And I'll add. Go slow on the drilling and CLAMP the table down so if ya get a catch, it won't spin the table into YOU.

[woodhead52]

After I enlarge the holes, do any of you think the rail bolt/nut against the left side of the trunnion will still be a problem? As it is, it certainly minimizes travel to the left.

I can also check on the hole issue with SS, but I did buy this rig 2nd hand.