My design of wheel axle is slightly different than the WoodSmith plans consequently making the storage unit slightly wider. That in itself is not a problem but an opportunity for increased storage space! My shop can cope admirably with a storage unit a couple of inches wider than the plans.
|View from rear of drill press showing nesting of both mobile bases|
I measured the resultant drill press mobile base width and changed my Sketchup drawings accordingly.
|Exploded view of the storage unit mobile base|
Again construction of this is utilising birch plywood and construction lumber. The sides and front of the base are rabbeted and are glued/screwed to the top. I decided to use pocket hole construction to augment the glue and rabbets.
The wheel blocking again was made from construction lumber but this time a cover plate was added. This covers the wheels but allow a full axle pin to be inserted from the outside and through into the side plate. This has a pair of washers, one either side of the wheel faces to provide a bearing face. Sufficient clearance is given by carefully measuring the washer and wheel assembly combined thickness and planing the blocking to that thickness + a few thousandths of an inch.
The axle holes were drilled with an drill guide of the correct diameter. This ensured that the holes were exactly drilled at rigt angles to the face of the boards. The holes were drilled blind into the plywood to about 13mm (1/2") deep. Then this hole had a 4mm through hole drilled into it. This ensures that the axle pin does not push through but still can be extracted, with a small diameter pin punch, for maintenance.
Then the top plate is notched out to suit the column of the drill press.
The fabrication was then rounded over with a router round over bit where necessary. Then it was finished with General Finishes Exterior 450.
The axle pin is held in place with a grub screw bearing onto a filed flat on the axle.