How to Make a Wooden Straight Edge for Woodworking

Joshua Farnsworth shows how to use hand tools to make a wooden straight edge, one of the most important tools in a workshop...see the full tutorial, tool brands, & photos here:

[darrylportelli]

One thing to mention is how you can check the straightness of your edge WITHOUT using another straight edge .. this is a precision tool that you are going to rely on so you need to test it frequently (espeically since it is made of wood and can move) ... To test it, place it on a flat piece of wood, like a piece of mdf, and strike a line with a marking knife using the straight edge ... Then flip the straight edge as if you are flipping a page if a book and align the edges of the straight edge with the knife line using the knife itself to help location and restrike the line ... Any deviation from the original line means that the straight edge is not perfectly straight ... The maximal point of deviation is twice the error .. for example if for an 8 foot straight edge that you made, there is 2mm deviation between the knife lines that you struck, it means that your straight edge has a 1mm concavity over 8 foot ... It is then up to you to determine what level of tolerance is acceptable ... Cheers

[ardvarkkkkk]

Make two strait edges at once. Put them side by side then plane them both together. Check straightness by sighting down the edge. Put them face to face to check flatness. This doubles the error. Keep planing and checking until no, or very little, light can be seen between  them when face to face. No measuring tools or strait edges needed to make one. For even greater accuracy, you need to make three at a time. The three strait edge method will get you strait and flat withing millionths, so is not applicable to woodworking. The arc and the other cuts should be done before planing the strait edge. Cutting the back can release stresses in the wood causing it to warp. Rather have it warp before the important part.

[duncescotus]

One commenter said make two. Actually you need to make three, and compare them to each other 2 at a time, 1-2, 1-3, 2-3, rotating every piece, until no light shines through the crack between the edges when any two are compared. With two pieces it's possible they could be curved and still mate up, but with three it's impossible. You can use some kind of powdered abrasive and on a flat surface like a piece of granite countertop or the tablesaw surface keep rubbing the edges together. Flip them over and every which way. It will take down tiny high spots until they're perfect. It will also make the edge perpendicular to the face. Keep "candling" them until not a trace of light can be seen. With this method and some aluminum you can get machinist grade accuracy. For wood they don't have to be perfect. Actually the commenter below is right, but the mathematics are such that 2 isn't enough. With three you can keep them all straight forever. He's right that you should relieve the back first, and that you can get them better than 1/10 thousandths accuracy. Quartersawn is good, but use split stock that's as close to straight to begin with. The curved back is good because it makes the bar stiffer in the center and keeps the edges a bit lighter so that weight doesn't sage them much. This is more important with steel than wood.

[djpenton]

Nice. Simple, too. I follow many woodworking folks on youtube, but Joshua often gives me the most understandable instructions. I used quartered white oak. I used my Lee Valley aluminum straight edge as a reference. I also tried just flipping the piece 180 degrees, which I think is simpler.

[styleden]

Great job! I plan on teaching and this may be my first student project.

[Finewoodworkingofsc]

Great video and information Joshua concerning the making of a wooden straight edge.

[junkyoumailtube]

IMO, a drawknife would make quick work of the curve on the back, rather than the time-consuming relief cuts and bow-sawing action. I would check squareness after cutting the curve, since the relieved stress might cause it to go out of square. Also not a bad idea to seal the end grain to help prevent movement. Nice tools in this video :)

[MrRichot]

I recently bought a very old wooden joiner plane (jack plane)? 14inchs long. Cleaned it up manage to sharpen it up pretty good. I couldn't believe (after a fair bit of practice) what it could do.
I can now for the first time plane lengths of board that can be joined WITHOUT gaps !!
Joshua, this vid made my day. I'm very sure I could now make a PROPER straight edge !!!! As a great little project.  The plane cost £5   I think Its between 80-100yrs old.
I've even made a special mahogany shelf for it !  
Thank you ....happy days.  (subbed)

[robertbrunston]

Very nice! You should be making more videos! Thank you.

[craigperry]

how long have you been doing the video's and working with hand tools. Great straight edge i will try this  

[MakeSomething]

Well done and explained! Your video production is fantastic.

[jimray]

Awesome!  Thanks for the post.  I have some well seasoned Cherry up in the loft that Id like to use for this.  Not sure if its 1/4 sawn or not but I will see if I can find a piece with tight horizontal grain to use unless you think differently.  Thanks again.

[JeffPeachey]

Do the shaped ends have any functional purpose or are they purely decorative? These types of curves seem very common in wooden European straightedges across many crafts.

[kirwanwoodkraft]

to check for straight lay the straight edge on its side and trace a thin line then flip it over and to the other side of the line if the line doesn't look straight the straight edge isn't.

[Snooze-vyyo]

Nice edge. Has down tho, nothing beats a good quality metal edge. They last forever and if stay true. For the most part, when dropped the will most likely stay true.

[MrMeanderthal]

when you are planing the "straight edge" it's better to put the plane on it's side and use like a shooting plane,  that way your  edge is straight AND square face.. planing on top like you did makes it almost impossible to be perfectly and continuously 90 degrees to the face.

also, the stability of the wood does not need to be perfect.. all you need to do is check it and reshoot if it has become a bit curved over time..

I use wooden straight edges all the time but I do not make curves on the back or fancy ends and I do not use hand tools to make them.. all I do is joint the face and edge of a board, rip a piece off of and re-joint the narrow edge to make sure it's straight after ripping it off the board.. mine end up in the scrap bin after the project is done

[anthonybeers]

my straight edge says Stanley on the cap iron. I just use the side of my long jointer.

[mikewest]

what tool did you use to cut out the length of the curve?

[MrRichot]

When you marked out the "curve". I thought. Oh here we go over to the Band Saw and I nearly clicked off. If I had a band saw in  my 8ftx6ft shop I would have to kneel on my bench to use it and then climb over it to get out of the shop !!  Hand tools Yeah :) 

[whittysworkshop]

A lot of the time here the planing was going against the grain :P