I don't doubt at all that your bandsaw table is not flat; even with the bolt on the infeed edge in place and tight. Furthermore, I don't believe you can make it flat using ordinary means.
I have mine "shimmed" so as to be square (almost) with the blade but even with shims in place it can be seen that the table is not flat.
These pictures I believe are self explanatory but questions are certainly welcome.
Bandsaw Table Flatness 053.jpg (1.84 MiB) Viewed 6679 times
Bandsaw Table Flatness 054.jpg (1.8 MiB) Viewed 6679 times
Bandsaw Table Flatness 057.jpg (1.65 MiB) Viewed 6679 times
Bandsaw Table Flatness 058.jpg (1.77 MiB) Viewed 6679 times
Please note that all of these images are of a table that has been shimmed to be square to the blade. Without the clamp(s) the left front corner is never perfectly flat to the rest of the table.
The last image shows that the table can be forced flat. As previously stated, this is caused by the slit in the front half of the table.
"Making Sawdust Safely" Dusty
Sent from my Dell XPS using Firefox.
I hope that what I show here applies to your issue as well as it does to mine.
What I have here is a kludge arrangement but it did convince me that the table could be almost flat. It is certainly flatter than it was when I began this effort earlier this morning.
The single bolt in the middle just does not do what is needed.
Bandsaw Table Solution (flatness) 002.jpg (1.74 MiB) Viewed 6675 times
Bandsaw Table Solution (flatness) 003.jpg (1.83 MiB) Viewed 6675 times
Bandsaw Table Solution (flatness) 004.jpg (1.99 MiB) Viewed 6675 times
There are two untapped holes on the underside of the aluminum bandsaw table. I am contemplating tapping those holes and using them along with the one we have been discussing to draw the table flat
"Making Sawdust Safely" Dusty
Sent from my Dell XPS using Firefox.
Hobbyman2 wrote:I would take the table off and check it again on a flat surface , be sure you have all washers if any are required installed correctly under the table.
warped tables are not good !
The trunnions are secured to the bottom of the table in a location where I seriously doubt they could cause this warping. Besides, the trunnions are not all that stout. Shims installed at the trunnions will certainly serve to square the table but I doubt do anything to flatten it or warp it.
I spent a little bit of time today checking out the trunnions. With the table removed,I checked to see if the four mounting locations for the table were coplanar. They are not. This would explain why the table needs to be shimmed. I am going to attempt to develop a way to make the trunnion mounting locxations coplanar before I put the table back on (no shims).
Reassembled Less Table.JPG (143.53 KiB) Viewed 6666 times
I contend that the slot in the table for blade entry is the root cause for all of this.
Last edited by dusty on Tue Apr 18, 2017 8:11 pm, edited 4 times in total.
"Making Sawdust Safely" Dusty
Sent from my Dell XPS using Firefox.
dynabase wrote:The fence is fine. I checked it with a straight edge prior to taking pictures. It is definitely the left edge of the table. I used the same straight edge on the right side of the table and it was flat all the way across. Fence does not rest on left side of table but does on right side of table.
Please clarify.
Is the left edge of the table the infeed edge?
"Making Sawdust Safely" Dusty
Sent from my Dell XPS using Firefox.
Does anyone have a pair of bandsaw trunnions that are not mounted. If so would you check them one against the other to determine if they are exact mirror images of one another.
From one of my two bandsaws I have removed the table with two objectives. One was to determine if it was reasonably flat when separated from the trunnions and the other was to verify that there is a need to shim the table to make it square to the blade.
A Bandsaw Trunnion Set 6.png (54.44 KiB) Viewed 6645 times
With the table and blade removed, I laid a flat plate on the trunnions to ascertain that the plate made contact with all four table mounting locations. Mine does not. It appears to me that at least one of my trunnions is different than the others and may be the reason why I have had to shim to get the table square to the blade.
Last edited by dusty on Wed Apr 19, 2017 11:27 am, edited 3 times in total.
"Making Sawdust Safely" Dusty
Sent from my Dell XPS using Firefox.
Not having the AL table and not having any fence that bolts on I'm having trouble picturing what is going on. I can see in the photo's from Dusty that it doesn't look like he has a fence and use of a added support seems to fix his issue (somewhat).
However I have no idea how the fence system mounts or what effect that might/would/could effect the table. I guess it is not something I need to know as I'm happy with the cast iron top I have but I do like to learn things so if someone could back up and get some pictures with more things in them it would be nice.
Ed
{Knight of the Shopsmith} [Hero's don't wear capes, they wear dog tags]
reible wrote:Not having the AL table and not having any fence that bolts on I'm having trouble picturing what is going on. I can see in the photo's from Dusty that it doesn't look like he has a fence and use of a added support seems to fix his issue (somewhat).
However I have no idea how the fence system mounts or what effect that might/would/could effect the table. I guess it is not something I need to know as I'm happy with the cast iron top I have but I do like to learn things so if someone could back up and get some pictures with more things in them it would be nice.
Ed
Ed, I do not know how the Kreg fence mounts but my fence (a standard Shopsmith Bandsaw fence) is secured to both the back and front of the bandsaw table. The fence during normal operation is secured in the back; however, it is adjustable both front and back.
It is my belief that the fence cannot be a contributor to this issue because of the way it mounts.
"Making Sawdust Safely" Dusty
Sent from my Dell XPS using Firefox.
There is no need to check your bandsaw trunnions. Mine are perfectly fine. What I suddenly realized is that the trunnions are individually adjustable. Just loosen the table tilt lock and rotate the trunnions to wherever you want them. I clamped the trunnions to a known flat plate and then locked the trunnions in place (table tilt lock).
I then reinstalled the bandsaw table. The table contacts the trunnions at all four bolt locations (NO SHIMS). I set the table to be horizontal (square to the blade) and reinstalled my cheater bar across the front of the table.
Much to my pleasure, the table is square to the blade and flat.
I did two things differently than I have ever done in the past. I leveled the trunnions without the table in place. Then after installing the table, I installed the flattening bar across the front edge of the table. The table is flat corner to corner.
This is not quite all of the story but I will present the rest with a diagram of the flattening bar. But with what I have presented here, you can validate your bandsaw table just as I have done. This is not the "fix" it is only the "concept verification". The fix is in the flattening bar mentioned above.
It feels so good to be back in the shop even though I am yet to smell sawdust. You have seen my shop. Sawdust will not occur until after the downsizing effort.
"Making Sawdust Safely" Dusty
Sent from my Dell XPS using Firefox.
