Ripping Accuracy with Vertical Panel Saws

Tips for making accurate panel rips, and a discussion of equipment tolerances and various quirks. March 25, 2007

How well does a vertical panel saw rip sheets? I am looking at a Safety Speed Cut 6400, and it looks like a pretty good saw, but it had me thinking about ripping. Sometimes I get sheets of plywood in that are not straight along their 8' length. Sort of banana shaped along the edge. I was wondering if there is any way to correct this on the panel saw. On shorter length cuts I would imagine you crosscut first, then rip either on the vps, or go to a traditional table saw.

I want to get a vps as I have limited shop space, and want an easier way to cut up sheet goods than how I do it now, which is on a Unisaw, ripping first, then crosscutting on a sled on the saw. I have to use a circular saw for any panels that remain wider than 26". I have read everything I can find on the site here, and most seem to prefer sliders, but I just don't have the room for one.

Forum Responses
(Cabinetmaking Fourm)
From contributor A:
I have a Saw Trax and I like it. I use it to rip full size sheets for only a few things. We got a CNC so only use it a few times a month. But before the CNC, it worked its butt off. To rip a straight edge, I would assume you would have to set the sheet in some sort of support. Maybe a 2" strip of oak so the material rides on the oak and the oak rolls on the rollers.

The only thing I would caution you on is when you rip, the upper portion you are ripping tends to slowly transfer weight into the kerf as you cut the material. At the end of the cut, with 6 inches or so, most of the weight is in the kerf and tends to slightly bind the blade. Not an issue for me, but might be for your shop.

From contributor J:
I have the SawTrax and am not quite as happy as I know many others are with it. Could be I just got too comfortable using a Striebig at my last job. Anyway, they do work fine for the money I guess; I just use mine to break sheets down and then finish up on the table saw.

As for sheets with a wavy edge, I would keep a piece of ply 4 or 5" wide, and dead straight, that can be screwed to the bottom of any wavy edges. Then you can run it through for a perfect edge. I don't see too many edges that bad from my supplier, so it's not an issue.

Lastly, contributor A is right about the saw binding on rip cuts. Keep a couple of shims nearby for whenever you're cutting on the panel saw. As you start cutting, stick a shim into the kerf, then when you're near the end of the cut, put in another shim. This will keep the top piece from binding and dropping on the blade, both of which cause a lot of heat, which will quickly destroy a carbide blade.

From contributor Z:
Another thought is this… I also rough rip, then TS. I made a vertical frame like a VPS but I clamp the top edge to the frame so it doesn't drop into the kerf. This way I have both hands free for the cut.

From contributor J:
On a SawTrax or SSC, you cannot clamp the panel to the frame as the stock is pushed past the blade. The only saws I know of that the blade moves over the work are the bigger Striebigs and Holz-Her style machines which don't require two hands to operate. What kind of machine are you using where you can clamp to the frame?

From contributor Z:
Pardon my stupidity - you are right. I made a frame similar to vps but I stand my sheets on it, clamp straight edge across and rough rip. Because of that I can clamp the top of the sheet since it is stationary and I use a skillsaw. I do not have enough room to move a sheet, so I had to go the other way - move the saw.

From contributor J:
Contributor J, I think you made a good choice. I bet you get better accuracy on your shop built frame then I do on my SawTrax.

From contributor A:
My Sawtrax is spot on. It cuts square, straight, and, provided we get the saw on the mark, very accurate. I bought mine off the show floor at a woodworking show and it had all the bells and whistles at the time. I had them remove the x and y measurement scales (should have kept them) but kept everything else. I also like it because it's a very safe saw. My part timer can use it without me worrying about it.

All in all, one of my better investments to this day. Paid for itself many times over. And for around 2K, it's easily affordable. To this day, the sales girl that works the shows knows me and we always talk. She gives me stuff, too.

From contributor J:
I wish they would give me stuff! I called them awhile back and explained the accuracy problems I was having with it, and they want me to buy additional parts to get it cutting square again! There's nothing broken, mind you - it's just an attachment they want me to buy. But it is safer and quicker than the circular saw and I'll keep using it until I can afford a slider. At least yours is working good for you.

From contributor A:
If the saw does not cut square, it's easy to adjust. At the bottom, in the center, there is a bolt that fits into a series of holes. If I remember correctly, moving the bolt one hole adjusts the square about 1/32 of an inch.

But I'm curious… What about the saw is not square and what were they trying to sell you? Nothing I've ever seen that they sell effects the squareness of the saw.

From contributor J:
I know about the adjustments – I've spent far too much time tinkering around trying to get it just right. The problem I have is with the frame of the machine. I can adjust it so it crosscuts accurately with the panel on the left side of the blade, or the right, but not both. I ran an 8' straightedge across the bottom and found that not all the support wheels are perfectly in line with each other. Which means if I crosscut an 8' long sheet, I'll get a different result than with a 4' sheet - all depends on which wheels are making contact. And there is no adjustment for these wheels.

To resolve this issue they want to sell me some sort of bolt-on frame attachment. The fact that they have such an attachment ready to go leads me to believe I'm not the only one with this problem.

Additionally, I have the older model PC saw, which is crap. The chances of getting a square edge with this thing are minimal. I still find it hard to believe someone actually thought it was a good idea to use such a flimsy saw. So that needs to be replaced also.

Someday I may get motivated enough to spend the time and money to fix this thing up (I should say this is only 3-4 years old), but for now it just breaks down the full sheets to smaller sizes so I can run them on the tablesaw. Unless I hit the lottery first, in which case I'll be rolling in a nice new Striebig compact.

From contributor R:
I've often wondered if it would be possible to use a Festool saw on a SSC or Sawtrax. Seems to me you'd get the best of both - an awesome cut and the ease of use of the frame.

I'm in a similar position of desire. My back and shoulders are just not up to humping sheet goods (I've got an Excalibur on my General), but have pretty severe space constraints, and don't do enough to justify a mainstream panel saw. I've read about the SSC and Sawtrax, but even their lesser cost is cause for pause. My current thinking is a Festool with a homemade frame setup - a square alignment tool like described above, and a series of support mounted to an interior wall that allow the sheet to be held vertically.

From contributor G:
The way to get rid of the wavy edge is what is called a dust cut, something that is done all the time for those of us that use melamine for cabinetry rather than plywood. If the saw is square, then the cut will be straight for all your rips. When doing your cross cuts, same thing - dust cut the end so it is square, then make the cut for the size of your panel. And yes, a couple of shims to stick in the saw kerf when cutting keeps the rip from binding on the blade. Best if you can find some made out of polymer, as they are less likely to wander away from the saw.