Imroved Fence for Fox 5/8" Morticer

[OPJ]

I must say that I've really been impressed with this machine since I bought it before Christmas. For only £130, stick a decent set of chisels in and it will serve you very well indeed. One thing I do not like though is the fence. It's neither square to the bed or parallel (vertically) with the chisel, so I decided I would try and do something about it this week.

First up, here's a shot of the existing set up. The MDF bed is sturdy enough, but it doesn't make up for a poor quality fence, which can easily offset your mortices if you're not careful (DAMHIKT)!

I began by cutting two sheets of 18mm WBP ply to 400mmx200mm each. If I was going to make a new bed then, I decided I may as well make a second one to sit on top when it comes to morticing narrower workpieces which the hold-down would not otherwise be able to reach. The jig here is based on Roy Sutton's design from his DVDs. After reading the latest British Woodworking however, I think I've a replacement already! :wink:

The secondary/"riser" bed sits on top of the existing one and fits in place over four 10mm dowels, so it cannot move anywhere. Keep reading and you'll soon see what the T-track's for... :wink:

I added a couple of 10mmx5mm Rare Earth Magnets to the base so it will hold to the morticer's bed. A couple more might do the job even better.

This is designed so that it replaces the MDF bed and so that it clamps over the existing fence. This means I'll be able to keep the fine adjustment of the back and forth movement. The "pressure pad" design is borrowed from Steve Maskery's Short Rip Fence idea. In this case however, it doesn't quite work as well as I'd hoped. I could have set the Bristol levers lightly lower but the back face of the fence is also tapered slightly, which doesn't help. Anyone have any thoughts on this?

Here you can see what I have so far - and also why I needed to include that T-track! We all hate having to hold the workpiece against the fence and it doesn't help your accuracy when the fence is all over the place either! I noticed Rutlands now stock these excellent Roller Guides and knew they'd be ideal for the job!

...Okay, if I'm being honest, this isn't entirely my own idea... Have a look at Bill-e's Idea.


I haven't given it a try yet but the MDF fence is already looking much squarer (?) than the existing one and I haven't looked at shimming it yet. I'm confident it will work well but I'd appreciate any feedback and thoughts from anybody reading this?

Especially if you have any ideas as to how I can secure the fence? I might buy another set of Earth Magnets and see how that goes...

I may also make something similar for my pillar drill now. :wink:

Thanks for looking,

Olly.

 

[Steve Maskery]

Hi Olly

When you say that the pressure pads don't lock as securely as you'd like, what exactly is the problem? Do you mean that the fence slides from side to side? Or you simply can't tighten the levers enough?

If the problem is that no matter how tightly you clamp the levers the table is still not tight on the original fence, it's probably the material you have used for the jig (MDF by the look of it. It's not stiff enough to resist the force you are applying. You have just two screws holding it together, by the look of it.

I had just that problem with the MK1 version of my short fence. I overcame it by making the sides higher, high enough to put a web between them. It improved the rigidity considerably.

If that's not the problem, but the tapered casting is not allowing the pressure pad to make contact all the way over its area. simply drill out the dowel holes to make the pad a looser fit. It will then be able to conform. You could also try gluing on some non-slip mat material. This is good stuff, but if you come a cross a god way to actually glue it to anything, let me know.

I think you basic design is sound, and I am planning something quite similar for my new drill press, as the old one doesn't fit very well and has some weaknesses of its own anyway.

Cheers
Steve

 

[OPJ]

Hi Steve and many thanks for replying.

My main problem is that I can still easily lift the whole assembly up and off the fence with the Bristol levers tightened. As I tighten them, the MDF pressure pads start to tilt to match the angle of the casting but the fit isn't tight enough to stop me from removing it. There's no problem with sideways movement as I've got a pretty tight fit! :wink:

I think you could be right; the MDF isn't strong enough. I've only screwed this together with no glue so far, but there is quite a bit of flexing, yes.

Sorry Steve, I'm not clear on what you mean when you say you put a "web" between your MkII fence? Would that be a thin piece of material to sit on top of the fence and prevent the sides of the jig from flexing?

I do like the idea of drilling out the dowel holes, thanks, so I'll give that a try before I go much further. I've also got a couple of non-slip router mats so I could lose a few inches off one edge. As for gluing it, I really don't know... I think I've seen some self-adhesive stuff on eBay somewhere but I guess you could try holding it with large-headed clout (felt) nails?

Thanks again for your thoughts on this Steve.

 

[Steve Maskery]

...you say you put a "web" between your MkII fence? Would that be a thin piece of material to sit on top of the fence and prevent the sides of the jig from flexing?

Essentially yes. I don't have a picture, I'll see what I can do, but I'm a bit pushed for the next couple of days.

Have a look at my Ultimate Tenon Jig in the last issue. I have a similar web on that to maintain perpendicularity.

If lifting off is the problem, I wouldn't bother with clamps at all, I'd drill and tap the fence itself.

S

 

[OPJ]

That's alright Steve, I'll have a look back through a couple of your articles and see what I can do from there.

Interesting point one drilling and tapping the fence... I've spoken to a couple of other members who own the same machine and the fences on their morticers are already pre-drilled?! :shock: If I decide to go down that road then, I imagine a HSS bit will drill it quite easily.

 

[Steve Maskery]

Yes no problem, and in fact, you wouldn't need to tap, would you? Just fasten into an embedded nut in the upstand of the new fence.
S

 

[Steve Maskery]

HI Olly this is my MK2 version. It's more resistant to splay becasue of the webs and it holds a ruler, spanner and the like, keeping them to hand but out of the way.

Cheers
Steve

 

[OPJ]

Thanks very much for the photograph Steve, sorry I haven't replied sooner.

I decided to take your other suggestion and drill through the existing fence to allow for some M6 bolts to secure the MDF sub-fence. This seems to work very well although I do need to take some photographs...

Don't worry though, you're efforts having gone entirely to waste as I could use your webbing idea to improve my bandsaw fence I made, which is also based on your table saw fence design. :wink:

 

[OPJ]

Okay. It's done! I've found what I've been looking for and I'm happy to say this setup seems to work very well indeed.

You can see in this first photo' how I've secured the MDF fence to the old one by drilling a couple of holes to take some M6 bolts. I did have the MDF fence fixed to the plywood base with screws but found that as I shimmed out the fence to get it square and parallel vertically, it had a tendency to pull the base out with it. So, I glued some 8mm dowels in to the bottom edge of the fence and drilled matching holes in the new base. This ensures that the ply base will always be flat against the machine's bed and, therefore, square to the chisel.

I added two or three strips of masking tape to the old fence in order to shim the new one in to square as the bolts are tightened with wing nuts from behind.

And here's an action shot for you! :wink: The roller guides really do work very well. You have to hold them tight to the workpiece when you tighten them, otherwise they will move away slightly as you turn the knob. You still have to move the timber from left to right but I'm no longer straining myself by having to hold the timber tight to the fence!

I hope someone else finds this to be of use at some point, thanks for looking.