Shooting board has me stumped.

[Blackswanwood]

When you check that the fence is square it is possible that the face you are referencing against is not the one that the plane registers against in use.

The plane blade will have created a small rebate over time leaving a small ledge that references against the plane body. It's this ledge and the fence that need to be square. Removing the ledge and allowing a new rebate to be created may solve the problem.

 

[Droogs]

When checking are you referencing the sqaure on the face the plane rides on and on the Leading edge face of the fence. This may be square but the trailing edge either in the fence or the bottom board may be slightly out and when lateral pressure is applied as you push the plane the whole fence and the board being trimmed are moving slightly backwards but only at the intersecting corner and creating a slightly obtuse angle.

hope that makes sense.

 

[SteL]

I think the above must be the most likely cause.

If you put a square on like...

I'm assuming you will see it is out of square?

 

[Chippymint]

Like others have said and before you go any further - ensure your square and set up is 100% square - simply find a flat reference, like a piece of wood properly squared and clamp it to a board or bench edge with a level surface. Stick a piece of A4 paper on the level surface that abutts the straight edge but does not overhang it. Place your square on the straight edge and draw a pencil line using the squares straight edge. Then turn your square 180 degrees. Make sure the square is accurately placed where the first pencil line was drawn at the bottom of the paper. Draw another pencil line the length of the square. Remove the square. If your square is square the pencil lines will be identical. If not do the check again. If the result is repeated and it shows the square is out, buy a new square. When you get another square repeat the check.
Assuming your square is square, check the shooting board for squareness. Adjust as required. Then back off the Planes blade, you use, place this on the shooting board (as you would when shooting) hold it firmly to the edge and place your square on the plane and check if it is square to the shooting boards fence.
This should tell you if everything is square or not. Assuming everything is square try shooting a board again. If you still have an issue then consider your technique and look to honing it.
Hope this helps.

 

[1275gt]

Would you look at that....

 

[1275gt]

I checked my square @Chippymint and the lines were identical.
I'm going to pare off the ledge formed and check again.
If it's still out I'll replace the fence with square set out as above.

 

[1275gt]

Thank you all for input so far. I'll keep you posted with results.

 

[Rob_Mc]

My best guess would be the workpiece progressively being pushed away from the plane as you push it through. I tend to only use shooting boards for squaring smaller section stock, with any wider pieces planed while held in a vice. While it's not impossible to shoot wider sections accurately you need a sharp plane, a light cut, and the workpiece prevented from being pushed away from the plane.

It's easy enough to check if this is the cause of your issue. Just firmly clamp the workpiece in place prior to planing, adjusting the position of the workpiece and re-clamping after each stroke of the plane. If the end result is square then you have your cause, and if not ... the mystery continues.

 

[ey_tony]

Coming from an organ building background, the first picture really says it all for me.
Those squares are adjustable and therefore prone to inaccuracy and were never considered a good enough tool for the precision work that was involved in organ building and back then, no self respecting organ builder would have used one in place of a precision square. They just weren't thought to be good enough.

Without wishing to offend anyone, the way I see it, they're good enough for what I'd consider rough and ready joinery, I even have one myself which to be fair is pretty decent but, for precision and where accuracy is to be repeated and essential, then a good quality square simply can't be beaten. I use mine as it happens for setting out/marking out much like a marking gauge for which they are very useful and even for unimportant/rough squaring but for precision squaring no, I have other squares for that job

The fact that they are moveable/adjustable means they have the potential to give false accuracy over the length due to engineering flaws or even the introduction of foreign bodies or failure to tension the locking mechanism correctly. There are so many variables which makes them potentially unreliable but that is just my view and others may argue differently.

We all have differing views on such things but if I was making a shooting board from scratch now, then I'd use a precision square to mark out a slot on the top board on which the timber to be cut sits, into which I'd let in a suitable piece of hardwood for the stop block at a perfect right angle. If the shoulder is even just one degree out it's going to transfer to the wood being trimmed so a precision square is an essential as a starting point.

I'd also have quite a low stop block (maybe 1/2"-3/4" protruding) so that more weight can be applied from one's hand heel with fingers hooked around the stop or placed on top of the timber being trimmed. One of the problems with using a shooting board for short pieces of wood is the wood being trimmed is often able to rock so a low stop block is better for getting more weight/grip onto the piece to hold it steady which pushing the plane. If the stop block is too high it restricts the amount of pressure one can apply from their hands and results in inaccuracy.

 

[Orraloon]

Just a quick for what its worth tip with squares. For setups and checking that things in general are squared and that includes other squares. Plastic drafting squares are very accurate(far as woodwork goes) and very cheap. I keep a 45 and a 60 as I sometimes still get out the old drawing board but they are also very good to make sure something is square. Humidity and weather dont affect them and even dropping them on the floor wont hurt all that much. Nothing wrong with a good engineers square either but you need to take very good care of it.
Regards
John

 

[Jacob]

Mark the workpiece with a pencil right angle line as close to the edge as you can get, clamp it, then plane it very slowly while you look at it as it cuts and it should be obvious what you are doing wrong