Cross cutting Plywood- Techniues

[skysharks]

Thinking out loud in the Shop today, after screwing up a piece walnut plywood. What whys do other use to croos cut panels of plywood.

I have not problem ripping plywood on the table saw, however cross cutting is a different story.


For years I have been laying it flat on my table, measureing it out then cutting it with a guide, and a circular saw. Until I get it down to manageable pieces that I can take it to the table saw.
But then I might have an edge that I need to be square, and it could be off by a bit.

Problems that I get with this is that I can be out of square at times by a 32nd or more. a 32nd over a longer distance of course grows.
It just ticks me off, I know there has to be a better way.

Oh yeah, I don't have the money for a panel saw I think.

Looking for suggestions and techniques, thanks

 

[JimmyC]

John,

The panel saw may not be as far out of you reach as you think here's one for $799 that is also portable and can be taken to job sites ( if it's a big job)...

http://www.rockler.com/product.cfm?page=6240&filter=panel saw

Or you can build one by plans and kit for about $350 ( plus wood and circular saw), either way the take up wall space in the shop)...

http://www.rockler.com/product.cfm?page=5311&filter=panel saw

Personally I use the same method as you(circular saw/tablesaw for initial cuts) because I don't cut enough panels to justify saw and space useage.

:eusa_thin I forgot about the last method, you could always buy a panel saw like a FELDER or something:rolf:.

Hope it helps.

Jimmy

 

[Nativespec]

One trick I use is to put masking tape (tightly) accross the grain where the cut will be (I use it on both sides). This will keep it from splintering.

David

 

[newtonc]

I have been holding on to plans from American Woodworker for making your own panel saw.From memory,I don't think it would cost much more than $150 or so.
If your interested,PM me your email.I'll dig it up and scan it and email it to you.

 

[McRabbet]

I use a large crosscut sled on my table saw for cutting or trimming any panel up to 32 inches -- it is big, but accurate. I agree with Mike's techniques, too, plus using blue painters tape to avoid any splintering of the face veneers.

 

[SteveColes]

I use a large crosscut sled on my table saw for cutting or trimming any panel up to 32 inches -- it is big, but accurate. ...

Me too

But it is so big and heavy, I use a hoist to get it out of the way

 

[BillPappas]

Sliding table on the table saw.

Bill

 

[sapwood]

Me too

But it is so big and heavy, I use a hoist to get it out of the way

8-O8-O8-O Dang Steve, your shop is really looking organized. Peg board hangys and chisel rack are super :icon_thum

Roger

 

[Gofor]

To add to what Mike said:
A good quality circular saw with a cast shoe as opposed to a stamped metal one, and a 40 TPI or better blade can give you good cut. I use a home made cutting guide that the saw rides on, with the edge being the cut line (made out of a 10" wide piece of MDO with a 2" wide piece of MDO on top for the sole plate to ride against. This gives a back edge of 2+" to clamp to without getting in the way of the saw motor after you run the saw down it to get an exact edge.) That way I don't mar the surface with the saw as it goes across and the edge works like a ZCI to prevent tearout. I use it with my PC saw and a 40 tpi DeWalt blade to square (both across the board and through the thickness) to get a good edge close to the finish width. After that, It is easy to reference the good edge against the fence on the TS, either to cut off the remaining waste, or if the piece is narrow enough, to put the keeper stock against the fence. When setting up my guide, I use a carpenters square to ensure it is square to one edge which I mark so I don't lose track of the squared edges.
I have found you can no longer rely on the sheet being square or the edges straight as bought.

Go

 

[DaveO]

To add to what Mike said:
A good quality circular saw with a cast shoe as opposed to a stamped metal one, and a 40 TPI or better blade can give you good cut. I use a home made cutting guide that the saw rides on, with the edge being the cut line (made out of a 10" wide piece of MDO with a 2" wide piece of MDO on top for the sole plate to ride against. This gives a back edge of 2+" to clamp to without getting in the way of the saw motor after you run the saw down it to get an exact edge.) That way I don't mar the surface with the saw as it goes across and the edge works like a ZCI to prevent tearout. I use it with my PC saw and a 40 tpi DeWalt blade to square (both across the board and through the thickness) to get a good edge close to the finish width. After that, It is easy to reference the good edge against the fence on the tablesaw, either to cut off the remaining waste, or if the piece is narrow enough, to put the keeper stock against the fence. When setting up my guide, I use a carpenters square to ensure it is square to one edge which I mark so I don't lose track of the squared edges.
I have found you can no longer rely on the sheet being square or the edges straight as bought.

Go

To add to what Mark said:
I do exactly as he mentioned, with the straight edge jig being the easiest, cheapest & simplest to make and the most utilized jig in my shop. I also have a 4' x 8' sheet of blue foam board insulation that I set my sheet goods on. That also the sheet to be fully supported, acts as a ZCI on the bottom side (I just cut into the foam board a little bit) and best of all allows me to crawl across the ply sheet keeping better control over the circ. saw, instead of leaning over and extending the saw out 4'. I can get finished edge cuts that way. But generally use it to break down the sheet into pieces that are easier to handle on the TS. Most of the time I am cutting several pieces to the same dimensions, and the TS is more repeatable than the straight line jig for specific dimensions.
MTCW,
Dave

 

[Gotcha6]

We sometimes have to cut off doors @ work to fit an irreglar threshold or sill. I made up a fixture from masonite siding and a 1x2 cleat. It works similar to the one mentioned above. I score the door veneer where I'm cutting it. The fixture is the same width out from the cleat as the shoe edge to the blade face & it can be clamped to the door behind the cleat to clear the motor. The masonite is soft enough to not damage the door finish. It's the same principle for plywood - just a longer fixture.

 

[charlie s]

The Festool system will make working sheet works a piece of cake. I back my truck up to the saw horses, slide the plywood onto the saw horses and use the track to cut the sheets to the exact dimensions I want. It will give a cut as smooth as any table saw and sure makes it easy to handle large sheets by yourself.

Charlie S

 

[adowden]

John,

I made a really useful router jig to square up slightly off pieces of wood and plywood. I got the plan from Jim Tolpin's book "How to Become a Professional Cabinet Maker". It has some great jigs in it. You lay this jig on top of your wood or plywood and line it up with the edge. You can check it for square and if it is slightly off, just clamp it to your plywood and use a flush trim bit in your router to square it up. It is very quick and easy. I will try to post a picture later today.

Amy

 

[Nativespec]

I agree with Charlie. I have the Festool saw and rails (table too). You clamp the rails to the plywood and the saw runs down the track. You can buy an additonal rail and join them together and cut the 8' length. By using this system, I can avoid changing blades on my table saw and leave the rip blade on it.

David

 

[Gotcha6]

For ripping I use the AccuRip. Goes up to 24", attaches to the circular saw & has a scale you can really follow. My only complaint with it is the fence foot is too short & you have a tendancy to slew the last few inches of your rip. Gotta work on that.....

 

[skysharks]

I want to thank you all for your response.
I have been using some/all of these techniques minus a few.

I would like to build a jig/cross cut sled for panels etc.

AMY- I would really like to see that router squaring up jig, that would be great.

Like I said in my original post ripping is fine it's the cross cutting that can be a problem at times.

Thanks for the links to the panel saw link.

Festol system, I'm not familiar with, I'll have to research that one.

MAC

 

[adowden]

Re: Cross cutting Plywood- Techniques

Mac,

Here is a picture of the router jig.

It is really simple. You can make the side piece from plywood, but the bottom should be solid wood jointed or ripped with a really good edge. Jim Tolpin made his jig 58" long including the overlap with the plywood piece. You can clamp it on the plywood and piece to be squared as well as on the right side of the solid wood and the piece to square. Use a bit with the bearing on top so that it rides against the solid wood. I love this jig when I am close but not perfect.

Here is a picture of my circular saw cutting jigs. I wish I had made these years ago. If you use the same blade, the edge of the thin plywood is your cut line, just plop it on you line and clamp it down. The long one is for ripping, the short one for crosscutting. Ideally it is better to have the whole circular saw supported with the plywood, but my old craftsman circular saw has a rivit that would interfere. Instead I double stick tape a piece of the same thickness to the part of the saw off the jig so it cuts square to the piece I am cutting.

Here is a great link to a similar jig from FWW.com. This is what I want to do next.

http://www.taunton.com/finewoodworking/ToolGuide/ToolGuidePDF.aspx?id=2659

Amy

 

[Mark Fogleman]

Prior to getting my Festool saw and guides I would have the place where I bought it make a couple of cuts with their panel saw and then clean it up with a finetooth blade on a Skill saw with straight edge. Pre-planning required when you get it cut in advance!

 

[Travis Porter]

I crosscut my plywood on my sliding tablesaw. Very easy and very accurate.:yes::tinysmile_classes_t

All the comments you got on crosscutting in general are right on. Cutting plywood is one of the reasons I wanted to go to a sliding saw. It can be made easier, but it is still a hassle. Several people commented on Festool, and it is some amazing stuff, but it costs an amazing price. You might want to check on some of the eurekazone stuff as a cost effective and comparable alternative.