Shaping wooden coachwork

[RonA]

Ive finally bitten the bullet & started replacing the wooden coach work (aluminium skinned a la Morgan cars) on my 1934 Wolesley Hornet special. Most of the timbers although they look straight have subtle curves. Although a friend was kind enough to lend me a large (almost commercial) bandsaw, I find it difficult to stop the blade wandering leaving a less than perfect square edge.
I had already purchased a clarke (MM) combined disc & belt sander to assist in the rebuild. Whilst it is brilliant on sanding flat surfaces & external curves, I found it to be useless for maintaining a square edge while sanding long internal curves.
After pondering the problem for a while I came up with idea of fabricating a square edged guide for the roller end of the belt sander. This has proved to be a great solution to the problem. I now cut the curve on the bandsaw close to the line & then finish off with the guide on the belt sander.
Above are pictures of the fabricated guide fitted on the sander & the rear woodwork on the car, the top rail on the panel appears to the eye almost straight but has a subtle radius on it of approx 110 ft. Fortunately I have the old bodywork to guide me.

 

[Parm]

Its these simple little jigs and fixtures that are an absolute god send when doing work like this, great stuff and good luck with your project !!

 

[RonA]

Its these simple little jigs and fixtures that are an absolute god send when doing work like this, great stuff and good luck with your project !!

Thank you for that.

 

[RonA]

Forgot to mention, most of the joints on the woodwork are half laps, some quite long as the timbers join at an angle. Original joints are absolutely perfect & I would guess machinery made at the factory.
I have borrowed a technique my next door neighbour ( a keen woodworker) came up with to remake them.
The joint is marked out & the two pieces of scrap wood clamped either side level with top of workpiece. A router is then used to cut the half lap to the correct depth, producing a perfectly flat bottom to the joint. The edge of the joint is guided by a small angle iron tee piece clamped so the router base runs along it, producing a nice square edge.
Photo shows general idea, sorry not the best sketch in the world but I'm sure you'll get the idea.
RonA

 

[Parm]

That's a sort of tennoning jig, very effective

 

[rmac]

If the bandsaw is set up correctly the blade should not wander of the line you are cutting. There should be guides either side of the blade, one attached to the moveable guard and one set below the table. There will also be a blade support to the rear of the blade again one attached to the guard and one below the table. These guides are essential due to the width and thickness of the blade plus the forces applied as you are cutting curves. They are set just off the blade to keep it running true as you follow your line

 

[RonA]

If the bandsaw is set up correctly the blade should not wander of the line you are cutting. There should be guides either side of the blade, one attached to the moveable guard and one set below the table. There will also be a blade support to the rear of the blade again one attached to the guard and one below the table. These guides are essential due to the width and thickness of the blade plus the forces applied as you are cutting curves. They are set just off the blade to keep it running true as you follow your line

The bandsaw certainly has two plastic guides (one side on & the other angled ) on the top support, both of which are properly adjusted & I have set the top support to give minimum amount of unsupported blade. Will check the bottom of the blade tomorrow in case the bottom guides have "slipped".
I will still need to sand the rails as I will be cutting from nothing on one end.
RonA