I sanded my benchtop. 80 grit followed by 120. I used a flat reference then marked the high areas and worked to blend them in. I also cleaned up the center glue line/offset.
The bench is roughly 21.75W x 2.75thk x 84L. I got a few sticks of extruded aluminum 60mm square tubing (85 inches long) that is quite flat according to a tight piece of monofilament. I laid the aluminum stock lengthwise and diagonally on the top. I am seeing about .016 - 0.025 inches gap longitudinally at the center of the bench - the center of the top is slightly lower than the ends. I measured at all parts across the bench lengthwise, parallel to the edges and diagonally.
Measuring crossways, the bench is fairly flat (0.016 or less) except at one end, which is dished about .03 inches or less. The dished area is about two feet in length and only a few inches wide. This was the result of a glueup issue and a slight difference between stock thicknesses. :eusa_doh:
The bottom is likely flat enough to do it's job.
I would never accept this tolerance for frame pieces on fine furniture but am wondering if it's close enough for a workbench. I will always know which area is a little bit off, right? My concern is that in further pursuit of perfection I'll screw it up worse than it is! :lol: :lol:
I could probably rig a base for a router flattening jig using the aluminum rails, and that's the reason I borrowed them, but now that I've looked it over and measured the problem areas I am wondering if it's worth it or not. Is there a potential problem I could run into in the future with this condition that I'm not aware of or is it good enough?
The top is no longer very portable. I can roll it from side-to-side but cannot carry it safely.
If the router sled idea will improve flatness and is doable with some planning I may try it. It will involve drilling holes through the assembly table to fasten down the frame and maybe a few hours constructing a sled. I have read up the details of this technique and printed out some pics. Maybe I just need a kickstart? If I use the router trick, how much cleanup will be required?
Opinions are appreciated.
Chuck
The bench is roughly 21.75W x 2.75thk x 84L. I got a few sticks of extruded aluminum 60mm square tubing (85 inches long) that is quite flat according to a tight piece of monofilament. I laid the aluminum stock lengthwise and diagonally on the top. I am seeing about .016 - 0.025 inches gap longitudinally at the center of the bench - the center of the top is slightly lower than the ends. I measured at all parts across the bench lengthwise, parallel to the edges and diagonally.
Measuring crossways, the bench is fairly flat (0.016 or less) except at one end, which is dished about .03 inches or less. The dished area is about two feet in length and only a few inches wide. This was the result of a glueup issue and a slight difference between stock thicknesses. :eusa_doh:
The bottom is likely flat enough to do it's job.
I would never accept this tolerance for frame pieces on fine furniture but am wondering if it's close enough for a workbench. I will always know which area is a little bit off, right? My concern is that in further pursuit of perfection I'll screw it up worse than it is! :lol: :lol:
I could probably rig a base for a router flattening jig using the aluminum rails, and that's the reason I borrowed them, but now that I've looked it over and measured the problem areas I am wondering if it's worth it or not. Is there a potential problem I could run into in the future with this condition that I'm not aware of or is it good enough?
The top is no longer very portable. I can roll it from side-to-side but cannot carry it safely.
If the router sled idea will improve flatness and is doable with some planning I may try it. It will involve drilling holes through the assembly table to fasten down the frame and maybe a few hours constructing a sled. I have read up the details of this technique and printed out some pics. Maybe I just need a kickstart? If I use the router trick, how much cleanup will be required?
Opinions are appreciated.
Chuck