Hi to all. So I checked my pro plus table and found the same problems. I clamped a straight edge on the table directly above the 3/4" table mount strip and drilled two more holes into the frame and inserted 1/4" bolts. Worked great. The table is flat on both ends. However I now see that each individual table slat has it's own idea of what flat is lengthwise. They are not attached together and can flex, so when you clamp your work down, the work piece can actually be forced downwards as pressure is increased (assumes that the clamp is on a different table slat). So I'm going to try using a couple hardwood strips that span the width of the table as spoil boards and set the work piece on top, then clamp everything together so the spoil boards span all the slats and are forced to the same flat plain. Let you know how it works!
Scott
Pro Plus Table Flatness
Moderators: al wolford, sbk, Bob, Kayvon
Re: Pro Plus Table Flatness
Yes on the individual slats reacting, well, individually to the clamping pressure. If the supplied clamps are used they must apply pressure over the same slat that they are mounted on or you can get a major deflection from two adjacent slats. I guess that's why so many have come up with different clamping methods.
Perhaps adding a slip fit filler strip in the slot created between two slats would cure that nicely?
Still thinking of replacing the plastic slat support with an aluminum angle.
Perhaps adding a slip fit filler strip in the slot created between two slats would cure that nicely?
Still thinking of replacing the plastic slat support with an aluminum angle.
My table is now flatter.
I had a .080" hump in the center of the table. I was able to reduce it to .025" in the middle of the Y travel, but some of that is probably the result of the gantry support bars deflecting. Here's what I did:
I replaced the (quite flexible) plastic bars that the T-tracks are bolted to with pieces of 1 1/2 x 1 1/2 x 1/8 x 18 1/4" long aluminum angle. The angle that went on the Y drive end had one flange notched 2" wide by 7/16" deep to clear the Y drive motor. I drilled holes in the angles using one of the existing plastic bars as a template. The plastic bar was tucked into the corner of the angle for the 2 mounting holes, and spaced away from one flange 1/4" for the T-track mounting holes, to make it easier to turn the nuts. I then drilled out the track mounting holes to 9/32" and the 3 of the angle mounting holes to 5/16", leaving one mounting hole in the track with the notch at 1/4" diameter. The oversize holes were to permit me to move the angle until it was absolutely parallel to the router travel. I also drilled three 3/16" dia. holes in the angle flanges that are used for mounting to the base, one near each end and one near the center.
I mounted the angle with the notch at the Y drive end, and got the top surface to within .002" (corrected--original post was .02")of parallel to the router travel, using a dial indicator. I then drilled through the 3/16" holes and the base and put 3/16 x 1" steel dowels through the holes to hold the angle in place. (I had to pull up slightly on the middle as I was drilling to get a zero indicator reading there.)
I mounted the angle for the other end, and laid a piece of T-track across both angles. I fiddled until the top of the second angle was at the same height as the first angle all the way across. Again, I drilled through the 3/16" holes and inserted dowel pins.
I bolted a piece of T-track on top of the angles on the X0 side, and used the dial indicator to make sure it was parallel to the Y axis.
Lastly, I bolted down the rest of the T-track. The end result was that the table is within .003" across both ends. However,the dial indicator shows the all of the T-tracks as being about .025" high in the middle as you travel down the Y axis. I loosened them, and rechecked, and still got the .025" hump with loose bars. I even turned one over to see if it was curved, but I got the same results. I suspect that the table isn't high in the middle, but that the gantry support bars are sagging this much from the weight of the gantry.
Note: If the gantry weighs 50 lb, I calculated that the deflection of the two 1" diameter bars would be about .010". So this is not all of the problem. But my table is a lot flatter now.
I replaced the (quite flexible) plastic bars that the T-tracks are bolted to with pieces of 1 1/2 x 1 1/2 x 1/8 x 18 1/4" long aluminum angle. The angle that went on the Y drive end had one flange notched 2" wide by 7/16" deep to clear the Y drive motor. I drilled holes in the angles using one of the existing plastic bars as a template. The plastic bar was tucked into the corner of the angle for the 2 mounting holes, and spaced away from one flange 1/4" for the T-track mounting holes, to make it easier to turn the nuts. I then drilled out the track mounting holes to 9/32" and the 3 of the angle mounting holes to 5/16", leaving one mounting hole in the track with the notch at 1/4" diameter. The oversize holes were to permit me to move the angle until it was absolutely parallel to the router travel. I also drilled three 3/16" dia. holes in the angle flanges that are used for mounting to the base, one near each end and one near the center.
I mounted the angle with the notch at the Y drive end, and got the top surface to within .002" (corrected--original post was .02")of parallel to the router travel, using a dial indicator. I then drilled through the 3/16" holes and the base and put 3/16 x 1" steel dowels through the holes to hold the angle in place. (I had to pull up slightly on the middle as I was drilling to get a zero indicator reading there.)
I mounted the angle for the other end, and laid a piece of T-track across both angles. I fiddled until the top of the second angle was at the same height as the first angle all the way across. Again, I drilled through the 3/16" holes and inserted dowel pins.
I bolted a piece of T-track on top of the angles on the X0 side, and used the dial indicator to make sure it was parallel to the Y axis.
Lastly, I bolted down the rest of the T-track. The end result was that the table is within .003" across both ends. However,the dial indicator shows the all of the T-tracks as being about .025" high in the middle as you travel down the Y axis. I loosened them, and rechecked, and still got the .025" hump with loose bars. I even turned one over to see if it was curved, but I got the same results. I suspect that the table isn't high in the middle, but that the gantry support bars are sagging this much from the weight of the gantry.
Note: If the gantry weighs 50 lb, I calculated that the deflection of the two 1" diameter bars would be about .010". So this is not all of the problem. But my table is a lot flatter now.
Last edited by FixitMike on Sat Apr 30, 2011 1:35 am, edited 2 times in total.
Re: Pro Plus Table Flatness
Mike,
Nice job. My table mapped out a little different than that with about half the table, X0 to X14 within .020, and X14 + gradually falling off to a minus .060. But I do like using the aluminum angle to get the flatness across the X. I got the indicator and the angle and some time tomorrow to try it out.
Thanks for your detailed description. I'll let you know how I make out. Meanwhile cut a few more small jobs on the left side of the table all coming out great.
Nice job. My table mapped out a little different than that with about half the table, X0 to X14 within .020, and X14 + gradually falling off to a minus .060. But I do like using the aluminum angle to get the flatness across the X. I got the indicator and the angle and some time tomorrow to try it out.
Thanks for your detailed description. I'll let you know how I make out. Meanwhile cut a few more small jobs on the left side of the table all coming out great.
Re: Pro Plus Table Flatness
So I had improvement with the extra bolts and spoil board clamp to achieve respectable results. Another observation I made was that the base piece has a crown in it when you sight down the length (y). This could indicate that the gantry slide bars are slightly to long. That could cause the two ends to not be at right angles to the table, so when you tighten down the table bolts it could force the table slats to conform and make them bow upwards. Just a thought....
Scott
Scott
Re: Pro Plus Table Flatness
Here's what I did so far:
I decided to use a square aluminum extrusion, 3/4" x 3/4" x 1/16 wall. The square shape makes it very stiff and it was easy to drill. Also, it fit over the Y-motor with no alteration. After I bolted it to the slats with it clamped to the base, my indicator told me I needed to raise the right end .035", which was a big improvement over the initial indicator reading with the plastic bar. I used brass shim stock and the table indicated starting on the left zero, rose over the next 4-5 inches to .010" stayed there for about 15 inches then dropped at the end back to zero. I put the original plastic bar over it with two hex bolts in their original track locations and the .035 shim and used it to locate the holes for the two mounting bolts to the frame. After every thing was tight, I got the same result as above which I'm happy with.
Now I will do the back the same way.
The removed plastic bar showed a lot of deformation. First at the bolt holes on the bottom, and every where on top that lined up to a slot in the track. I think this had a lot to do with the bad readings before. The plastic was also very hard to remove, I had to pry the plastic bar at each bolt to free it.
Here are a couple of pictures.
I decided to use a square aluminum extrusion, 3/4" x 3/4" x 1/16 wall. The square shape makes it very stiff and it was easy to drill. Also, it fit over the Y-motor with no alteration. After I bolted it to the slats with it clamped to the base, my indicator told me I needed to raise the right end .035", which was a big improvement over the initial indicator reading with the plastic bar. I used brass shim stock and the table indicated starting on the left zero, rose over the next 4-5 inches to .010" stayed there for about 15 inches then dropped at the end back to zero. I put the original plastic bar over it with two hex bolts in their original track locations and the .035 shim and used it to locate the holes for the two mounting bolts to the frame. After every thing was tight, I got the same result as above which I'm happy with.
Now I will do the back the same way.
The removed plastic bar showed a lot of deformation. First at the bolt holes on the bottom, and every where on top that lined up to a slot in the track. I think this had a lot to do with the bad readings before. The plastic was also very hard to remove, I had to pry the plastic bar at each bolt to free it.
Here are a couple of pictures.
- Shim under table end, aluminum square
- Aluminum square bolted in place
- Removed plastic bar hole deformation
Re: Pro Plus Table Flatness
Thanks for the responses and your findings.
As I previously stated, I am a Mechanical Engineer, so I took some measurements, made some assumptions, and did some calculations. Here's what I got.
Measurements: The two round steel bars that go across the gantry (X direction) are 31 inches long and are 20mm (0.788 inch) diameter. The two round bars in the base are 29 inches long and also 20mm diameter.
Assumptions: The Gantry package weighed in at 48 pounds. Subtracting out the packaging, control box, cables, software boxes, clamps, etc. Assume the Gantry assembly with router installed weighs 40 pounds. Assume the router carriage with motor, shafting, router, etc. weighs 10 pounds. Assume the threaded rod carrys no load. Assume at the center both steel shafts share the load equally.
I did standard deflection calculation for the shafts with the assumed loads and under their own distributed load.
So here is what you should get, or close to it.
Across the front or back in the X direction a perfectly flat table you will see a rise in your indicator of 0.0084", which is really the deflection of the bars at the center. As previously reported, I indicated .010" after making the install of the aluminum square and adding the brass shim.
At the very center of the table, due to deflections of the four steel shafts under load, you should see a maximum deflection of 0.0285" if your table is perfectly flat.
Remember, the aluminum track will also deflect, so Mike's measurement of 0.025" at the middle completely corresponds to this.
If your table then maps out at about 0.030", there is nothing you can do to get it flatter, it is flat, your seeing normal deflection. If your table shows .080" like Mike's or .090" like mine you can get it to .030" making the improvements like we did.
Two things that did my table in were the use of the plastic clamping parts as previously reported, and what appears to be a machining error that made the right side of the table about 0.035 too low. I think Next Wave can control this better and deliver tables that consistently map out to about 0.040" total which would give them a reasonable tolerance.
Thanks.
BillK
As I previously stated, I am a Mechanical Engineer, so I took some measurements, made some assumptions, and did some calculations. Here's what I got.
Measurements: The two round steel bars that go across the gantry (X direction) are 31 inches long and are 20mm (0.788 inch) diameter. The two round bars in the base are 29 inches long and also 20mm diameter.
Assumptions: The Gantry package weighed in at 48 pounds. Subtracting out the packaging, control box, cables, software boxes, clamps, etc. Assume the Gantry assembly with router installed weighs 40 pounds. Assume the router carriage with motor, shafting, router, etc. weighs 10 pounds. Assume the threaded rod carrys no load. Assume at the center both steel shafts share the load equally.
I did standard deflection calculation for the shafts with the assumed loads and under their own distributed load.
So here is what you should get, or close to it.
Across the front or back in the X direction a perfectly flat table you will see a rise in your indicator of 0.0084", which is really the deflection of the bars at the center. As previously reported, I indicated .010" after making the install of the aluminum square and adding the brass shim.
At the very center of the table, due to deflections of the four steel shafts under load, you should see a maximum deflection of 0.0285" if your table is perfectly flat.
Remember, the aluminum track will also deflect, so Mike's measurement of 0.025" at the middle completely corresponds to this.
If your table then maps out at about 0.030", there is nothing you can do to get it flatter, it is flat, your seeing normal deflection. If your table shows .080" like Mike's or .090" like mine you can get it to .030" making the improvements like we did.
Two things that did my table in were the use of the plastic clamping parts as previously reported, and what appears to be a machining error that made the right side of the table about 0.035 too low. I think Next Wave can control this better and deliver tables that consistently map out to about 0.040" total which would give them a reasonable tolerance.
Thanks.
BillK
Re: Pro Plus Table Flatness
I used 1 1/2" aluminum angle as "ledger boards" and mounted 1" thick x 3" wide x 36" long "1030" extruded bars to form a table top.
The pro plus uses a similar extrusion that is slightly thinner.
each section can be individually shimmed if required, and the angle is bolted to the machine frame at numerous points using "t" nuts to maximize clearance inside the machine frame. There are adjustment bolts on the corners to assist in getting the angle level to the gantry before tightening the angle to the machine frame.
very strong and easy to make. I probably overdid the bolts, but it is very flat and quite strong.
The pro plus uses a similar extrusion that is slightly thinner.
each section can be individually shimmed if required, and the angle is bolted to the machine frame at numerous points using "t" nuts to maximize clearance inside the machine frame. There are adjustment bolts on the corners to assist in getting the angle level to the gantry before tightening the angle to the machine frame.
very strong and easy to make. I probably overdid the bolts, but it is very flat and quite strong.
- Attachments
-
- extruded table sections fastened to frame
Re: Pro Plus Table Flatness
Been awhile since I posted to these forums. Been frustrated with the trying to carve simple lettering as the table moved away from the router as the x-axis increased. Did not have the resources for replacing the bar as previous posters have done which I do like.
I took off the slats, put an old bit in upside down and then using the jog, I ran it along the plastic base from left to right to see how much it went down. Then I used metal tape until it was level.
I tried to do the same for the back, but the router of course does not travel that far back. I improvised by tieing a long pipe cleaner onto the router and then jogged it until it almost touched. I found the back side was level to my naked eye.
I then carved a pattern 1/16" deep in some scrap pine and it still seemed off. However, thinking it was the wood, I ran it through a thickness planer and ran the pattern again. It was the wood. I don't see any change of depth along the x-axis now.
Now maybe I can get back to the enjoyment that I thought I would have when I got this thing.
I took off the slats, put an old bit in upside down and then using the jog, I ran it along the plastic base from left to right to see how much it went down. Then I used metal tape until it was level.
I tried to do the same for the back, but the router of course does not travel that far back. I improvised by tieing a long pipe cleaner onto the router and then jogged it until it almost touched. I found the back side was level to my naked eye.
I then carved a pattern 1/16" deep in some scrap pine and it still seemed off. However, thinking it was the wood, I ran it through a thickness planer and ran the pattern again. It was the wood. I don't see any change of depth along the x-axis now.
Now maybe I can get back to the enjoyment that I thought I would have when I got this thing.
Re: Pro Plus Table Flatness
After reading the posts here, this is what I did because I was seeing some inconsistincies when doing v-carve letters.
I removed the aluminum table top and used the router in jog mode and shaved the plastic "bars" that the table mounts to. I had to turn the gantry around (being very careful not to lose the height adjustment I used on the front) to do the far side and then turned it back around to original position.
It only routed to about 3/4" from the ends of the bars and I finished those off with a sanding block and 80 grit sandpaper while repeatedly checking my progress with a dial indicator that is made for checking the side clearance of saw teeth. ( I was once a tool sharpener)
Through various means I determined that I removed about 12 thousandths more on the right side than the left side on the front bar and only a couple of thousandths difference on the back bar.
My results are much better now, though not quite perfect. I don't think this machine can accomplish perfection. To the trained eye I mean of course, not true perfection. I have been making quite a few v-carved signs and the results are acceptable. Just barely from my point of view, but definitely a saleable product. I haven't sold one yet, but I've only had the machine for a few months and there has been a rather steep learning curve. We are designing some awesome architectural elements though (porch brackets and such) and my hopes are high to sell them to lumberyards. We think have some rather unique designs that could really take off.
Wish me luck!
Wayne Van
I removed the aluminum table top and used the router in jog mode and shaved the plastic "bars" that the table mounts to. I had to turn the gantry around (being very careful not to lose the height adjustment I used on the front) to do the far side and then turned it back around to original position.
It only routed to about 3/4" from the ends of the bars and I finished those off with a sanding block and 80 grit sandpaper while repeatedly checking my progress with a dial indicator that is made for checking the side clearance of saw teeth. ( I was once a tool sharpener)
Through various means I determined that I removed about 12 thousandths more on the right side than the left side on the front bar and only a couple of thousandths difference on the back bar.
My results are much better now, though not quite perfect. I don't think this machine can accomplish perfection. To the trained eye I mean of course, not true perfection. I have been making quite a few v-carved signs and the results are acceptable. Just barely from my point of view, but definitely a saleable product. I haven't sold one yet, but I've only had the machine for a few months and there has been a rather steep learning curve. We are designing some awesome architectural elements though (porch brackets and such) and my hopes are high to sell them to lumberyards. We think have some rather unique designs that could really take off.
Wish me luck!
Wayne Van