Thursday, July 12, 2018

Wadkin Dimension Saw: Resurrection (Phase I), Part II

I’ve been too engrossed with project work to be able to make it back up to Rees shop in NH, however he has made a lot of progress on the machining work. In fact, the work is complete after nearly 40 hours. I asked him to take some pictures as he went and he kindly obliged.

The sliding table’s upper surface was one of the first things Rees tackled, and just a few passes with the planer shows the condition of the surface quite well:


The table was bowed up in exactly the last place where I could tolerate it, right next to the saw blade when ripping stock.

Just like hand-planing a piece of wood, you can reach a point where most of the surface is done, but the ends remain low and many passes are yet required to flatten things out:



After about 0.023″ (0.6mm) had been sliced off, there was at last a flat table top:


A bit more than that had to come off the underside of the table, along the runs where the linear rail assemblies are fastened. All in all, over 0.05″ (nearly 1/16″) was removed in correcting the surfaces, which was about the degree that things appeared out of whack with the table at my shop when it was on the machine.

Curiously, one of the underside rail supports was dead straight until the last 12″, where it veered off of parallel with the other rail by 0.005″. This would have of course contributed to the difficulties I found in getting the table bearings tightened  – it was not possible to get them adjusted properly, and I had to run the table such that it had too much play in the middle of the stroke and got slightly tight at the end of the stroke. Those bugbears are going to be problems in the past now, it would appear.

After the upper table was sorted Rees got to work on the support beam:


The support beam was decently straight, yet was improved to a higher standard than before, with about 0.012″ taken off.

One of the tricky parts was dealing with the linear rail support ribs, which have a sloped top and a curved bottom surface:


Rees also dressed the sides of the casting to clean them up:


The sliding table casting has also been cleaned up in the same manner.

Another view of the planing work underway on a linear rail rib:


With the two castings straightened out, the mitre fence was then worked on, and after that, the holes for the mitre fence in the table were redone. Both the main pivot hole, which had been heli-coiled previously as a repair, and the worn out detent holes for the various mitre positions were bored out, plugged, and redone. The detent holes are conical. The pivot pin threads were cut off and a Whitworth 1/2″x12TPI set screw was installed.

Here’s the primary mitre fence position after the re-working:


I had Rees add a second position of pivot and detent holes in the middle of the table, so that when I do obtain a back mitre fence to pair with the main mitre fence, it will be much more usable tool in terms of the sliding table being able to support the work:


In case you’re wondering what a back mitre fence is, here’s a picture from the Wadkin PP saw brochure showing it in use (see pic lower left):

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