New Table Saw Fence – Fine Adjustment Test

I’ve gone and bought a new table saw fence. It’s an upgrade for this type of machine albeit the Charnwood variety. The fence I currently use could never span the full distance of the extension I built, and in a previous video you can see me having to clamp the fence down to make a simple top mitre cut.

 

The old fence was actually sold as an upgrade for bandsaws and I was also never quite happy with how it connected to the cast iron top. This new fence is supposedly an upgrade for this type of table saw, although mine is a very old Axminster variety without soft start and breakings. I aware that Draper and Scheppach also sell similar machines, but the newer versions doesn’t seem to have this lip at the front of the cast iron top.

So in this video I’m going to install the fence and do a few other modification to the saw to keep it running a bit longer. I start by dismantling the old fence and hoping I don’t need to put it back on to make any cuts. After holding the front rail in a few positions, I decide the best thing to do is get my apprentice to work on this. Only joking, I’m a one man band, a lone wolf, no one wants to be my apprentice anyway.

It’s quite a heavy piece of aluminium.

I decided to take a few pieces of scrap 20×20 aluminium extrusion and test the positioning. I have three mountings holes to work from, but I start by installing two pieces and resting the front rail on top to check the fence will sit in a good flat position.

After a bit of chin scratching I decide to cut the aluminium profile down using my trusty cross cut sledge. I’m going to install the aluminium profile with some leftover t-nuts from my CNC machine build.

The half attached to the cast iron gets screwed down from the top, while I need to punch and drill holes into the profile for the machine screw which will hold the front rail.

I bolt the pieces first to the table, and after adding the t nuts to the opposite ends of the extrusions, I slide the front rail into position. I then slacken the machine screws at the cast iron top, and use the square to make sure everything is at 90 degrees while tightening everything.

To set the fence parallel to the blade, there are four machine screws at the T of the fence which can be slackened and adjusted. I do this by eye, looking at the shadow created along the mitre channel in the top, and then moving the fence looking at the spacing at the front and back of the blade.

I prematurely added the measuring tape which was supplied with the fence before realising the fence face was not square to the cast iron top. So I will have to come back and sort that out.

If feels super sturdy. With that other fence I’m going to fit it to the back just so I still have the option of using the router table.

So that’s 15.5 and that 15.46.

The old fence has a clever method, using an eccentric spacer to adjust the face of the fence so it is square to the cast iron top. Unfortunately the new fence doesn’t have such a mechanism, and when I was checking its face was square to the top, I realised it wasn’t.

I’m just checking how square this is, and it’s definitely isn’t square. This thing isn’t square.

I decided to take the new fence apart, drill a few extra holes into the joining piece, and then adding a length of aluminium c-beam to use as a fence. This was an extra piece I bought again while making my CNC machine.

Ok the fence is looking pretty good but I want to add something to the face here just so that I can avoid these gaps, especially when I’m doing mitres. And what I’m going to use is this quite thick piece of melamine MDF.

I’ve just set the depth stop up here.

So the fence is a lot better but the problem I have now is the ruler is not aligned with the face.

I just cleaned this with a bit of turpentine and re-sticking the tape back on.

I then got a little optimistic, designed a fine adjustment mechanism to move the fence. This was a prototype which I partly 3D printed and partly milled on the CNC machine. The rack which I could make from aluminium profile once my larger CNC machine is complete, bolts onto the underside of the front rail, and the pinion or gear is held at the correct position in a mount with a bearing. This is bolted onto the underside of the fence near the clamping handle. When I pull the rotation knob back the gear engages with the teeth of the rack, and I can rotate it moving it along, and when I don’t want it to engage I can just push it forward.

You can see the mechanism working here. I think the teeth need to be a lot finer or the rotation knob a lot larger to get that delicate movement you’d really need, so I’ll stick with knocking the fence with my knuckles for now.

And the real problem is I just can’t lift the fence up, I have to slide it to the point where there is no track and then… even then I can’t lift it up.

It also occurred to me that the channel in the c-beam which I’m using for the fence could be really useful for dust extract. I think I’ll work on consolidating the router table and table saw fence into one things, but I’ll save that for another video. I hope you found that interesting, thanks again for watching and you’ll see me in the next one.

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