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I am in the process of building a binding jig and the parallelogram isn't staying square as it goes up and down . Hopefully the pictures can show what's going on. Does anyone know what the problem could be? The only time it is square with the table is when it is straight.

I would suspect that your 4 bolts aren't evenly spaced on either then horizontal or vertical plane. If for instance one pair is set to 2" apart and the other is 2.125" apart, the parallelogram won't stay parallel to your bench surface.

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I think Chris nailed it. Off on either, or both planes, and it will do that. Just looking at the second picture looks like the horizontal spacing is off. You have to be the same from CL of bolt, to CL of bolt to the far edge of the wood. On both the top and bottom. And they have to match on the vertical

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Joe Beaver
Maker of Sawdust

Chris is correct, The upper and lower arms of he parallelogram must be identical.
The pivot points on the fixed side must be plumb.

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My memory is so good, sometimes I remember things that never happened.

i figured it was something like that. i dont have a drill press i just used my drill and tried my best to get them staight. i really dont want to get a drill press just for this so what should i do?

Make a drill guide by drilling two holes in a block of hardwood. Use it for both pairs of holes. A drill press in itself will not solve your problem. Yous still need one way or another to get the spacing. As for the drill press, find a friend, school wood shop, etc. Are you drilling through both at once?

You will likely find an inexpensive bench top drill press on CL for $50 or less.
It is invaluable. There will be many times when you wish you had one.

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My memory is so good, sometimes I remember things that never happened.

One way of drilling a fairly straight hole with a handheld is to carefully mark both sides of the board, center punch the marks, drill holding the motor as straight as you can but only half way through, flip the board over and do the same but drill on into the other hole.

In that manner any error will be only half of what it otherwise would have been.

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Joe Beaver
Maker of Sawdust

Suggestions

http://www.popularmechanics.com/home/ho ... ght-holes/

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Ken Cierp

http://www.kennethmichaelguitars.com/

The first two are pretty slick, Ken!

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

The bolts in the main slider frame are vertically closer, than the bolts on the laminate trimmer platform IMHO. To fix it, dismantle and then plug the top holes with a glued in dowel.
Sand smooth, then without the two horizontal plates bolt the two together at the lower holes then redrill the top hole after clamping the tops over each other using the trimmer base as the spacing template. Also if you use only one pair of holes on the laminate trimmer base as a master set, you can check both sides are spaced the same.
A drill press is not required, you seem to have the the holes straight enough that it assembles

you have a fatal flaw in your design. Your grain is in the wrong direction in your arms. They can crack . You want the grain running so the holes will be drilled across the grain.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Also if the two pieces were longer you will get less error for the same vertical movement (I think).

Buy a Craig's list drill press. Or, a grizzly bench drill press. Not expensive and you will use it endlessly. My drill press (it's a powermatic) is the third most used tool in my shop.

Edit: before I could justify buying such tools, I used a local community wood shop that has all the major tools. I built all my jigs then, including the one u are building. Maybe u have a resource like that in your town?

What John said. If you rebuild you might consider using 3/4" birch plywood.

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Steve Smith
"Music is what feelings sound like"