07 May 2012

St. Peter's Cross-1st, failed attempt.

When my son & I built our Roubo bench, we added a parallel guide to the bottom of the leg vice.  Information on an alternative, the St. Peter's Cross, was discussed when the Benchcrafted prototype was recently introduced.

In haste we made an attempt to make one using 25x6mm steel flat bar.  

1st we cut grooves in both the inside of the leg vice & the bench leg to accommodate the steel bars.

Halfway up we notched a space to fit the nut and bolt (6mm) which hinged the two bars in the centre, thus forming the cross.

We rounded the ends of the bars to prevent them from catching the wood:

We fitted the cross with 6mm threaded rod on the two top pieces and the bottom pieces were not attached in any way.

Our St. Peter's Cross didn't work for the following two reasons.  1.) The steel flat bar is only 6mm thick, so the vice has play from left to right when being loosened or tightened.  This seems like a minor problem that may be fixed by thickening the ends of the two bottom pieces (with a short bolt & nut I guess), thus making the fit inside the wooden grooves snug.

2.)  The second problem is the major one.  When the vice is tightened, the cross ensures that the vice moves in parallel to the bench leg.  But once the piece of wood being held in the vice is engaged, then the bottom of the vice keeps on moving in.  In other words the leg vice does not remain parallel when engaging the workpiece.  And as far as I understand, this is the main purpose of the Cross.  It seems as if the two bottom pieces of the cross are slipping and riding up the groove.  This then puts the vice out of parallel, which loosens the grip on the workpiece being held. I attach a short video to demonstrate this.  So far I have no solution, so if anyone can help, it would be appreciated and shared. (Please note the video was taken sideways in order to better fit the long leg vice.  So the bottom of the vice is on the right of the picture-that's where you should pay attention).

05 May 2012

Temporary Handplane Cupboard

I had a choice.  Either keep my handplanes in my existing steel cabinet where they were hard to reach, and kept bumping into the steel top and each other every time I took them out.  Or wait a few years before I had the necessary skills to make a proper hand-tool storage cupboard.  The third option was a plywood open box assembled with rebates and glue. The shelves rest on cleats which were screwed into the sides.  I may or may not put a door later.  If I put a face frame, it will only be for the practice.  It took half a day to assemble, my planes are not touching each other and easy & quickly accessible, so as to allow me to get onto the real thing-making furniture.  I must say it does look ugly, so I do prescribe to the aesthetic thing when it comes to some tools as well as tool storage.  But I do have instant gratification with this cupboard.  I suppose finding that balance will always be necessary.

In terms of classification, I put the two jointers on top as they are too long to fit into the space.  next come the block and shoulder planes.  then the fore planes-scrub, fore and #5.  Then all the smoothers and scraping planes.  Finally the plough and rebate planes are at the bottom.  I have used up 60% of the cupboard so I may put a drawer and a lower compartment for storage later.