Straighten plywood edges

[mike]

I am a beginner woodworker and I am looking to make a rip jig for circular saw. I have a scrap piece of ply with both long edges crooked. Any ideas to get straight edges? I was thinking of attaching straight 1x3 to ply edges, with 1x3 running along Tablesaw arm. Hopefully this would create new straight edges.

Any other suggestions?

[Jens Jensen]

How wide is your plywood? What you can do is take a 1x3 and screw it down to one edge of plywood then take the saw and lay the base plate to the edge of the 1x3 turn on your saw and cut the bad edge off and then you have you cut off jig  if it is really wide enough put the 1x3 inboard from edge and do the same  that way with the edge that is not cut off you can use that for clamping your jig to whatever u plan on cutting

[Onno Kok]

It is possible to guide the crooked piece though the table saw if It is fastened to a straight board. The straight board would need to be wide enough to support the board with out it rocking. Overhang the crooked edge over just enough to remoe the waste, while the straight edge rides along the rip fence. Once one side is done remove the straight board and run the other crooked edge through the blade. This will insure both faces are parallel.

Having said that it might be easier to find a piece of ply that has one factory edge to work with.

Onno

[Ken Darga]

Shop made circular-saw rip-cutting guide/jig:

Base 1/4'' hardboard---10-12'' wide

Guide 1/4'' hardboard x 4'' wide---(width to minimize warping and facilitate clamping)

Guide needs one edge with a straight cut along the saw base.

Guide clamped and glued to base.

Alternate guide:  1/2'' plywood---

screwed from underside, using flat head screws---

counter-sunk slightly.

Make 1 for cutting 8ft sheet goods and another 4ft long for cutting shorter pieces.

    

[mike]

I will give it a go. I will start with crosscut guard. I will start with crosscut guide jig.

Thanks

[Jens Jensen]

.The question was how to make a ripping guide for circular saw .So to do it correctly you need to rip it with accordance to width of base plate of saw. You dont do that on a tablesaw without measuring from your fence to saw blade ,so just screw a board on your plywood and make your cut and it is all done with .hope his clears matters up

[mike]

Yes, I understand. I will get it done this weekend and report back. I have a 1x3 straight high quality piece of wood, and was wondering if I could use this as guide to attach to plywood?

[Onno Kok]

Yes, is the simple answer. Attach your straight 1x3 to the crooked plywood insuring that the distance from the 1x3 to the edge of the plywood is greater than your circ saw width (distance from base edge to blade). That way when you make the first cut your saw will be guided by the 1x3 and trim the plywood straight. after that you can use it as a rip guide, just align the edge of the plywood to your layout line, clamp in place and saw away. This helps prevent chipout as well, but it's still a good idea to cover the cut in masking tape first if you want a clean cut.

Onno 

[David Dean]

if this well help Jen helped me with this one.I got a 4' and a 6'

[Ken Darga]

Personally, I've found a 4'' wide birch plywood guide to be less likely to distort.

6" wide stock is even better.

Store ''FLAT'', (horizontal), when not in use.

[mike]

Dumb question. Why don't most people use a 1x12 instead of plywood as base. Is it a matter of cost? Just curious.

[KregRep]

Plywood or hardboard makes a much better base because it is stable. A 1x12 is very likley to bow or warp over time, leaving your saw guide inaccurate.

KregRep

[mike]

Thanks for answering.