Does anyone here OWN a MLCS pins and tails half blind dovetail and box joint jig?

Roger Tulk

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St. Catharines, Ontario, Canada
I am asking this very specific question because it is very specific to this piece of... er, jig. I bought this a very long time ago, and it has moldered on my shelf for years, until I made a trip to MLCS and got the parts I was missing in terms of guide thingies and router bits. So, I took it out of the box, and decided to do some ¼" box joints in ½" Birch Ply. This is a test cut, so I'm not fussy about the wood.

I read the instructions, as I have done many times, and slowly followed them one by one, leaving nothing out. I made up the setup boards clamped them under the front clamping bar, tightened the bar, and then went to move the edge guides so that the workpieces would be in the proper position when I took the setup piece out and put the workpiece in. I found I could not move the edge guides, because the screw and spring that hold the clamping bar put so much pressure on the setup guide that it is impossible to move smoothly, or at all.

Checked for a video that would show me how to set it up. There are none. There are no videos showing the thing in use. MLCS seems to have paid all its attention to the through dovetail jigs. Oh, I had to cut the ends off the knob to clear the template holding screw :rolleyes:.

Th photos below show the parts I have for the clamping bar, the edge guide in place according to the manual, the order in which I assembled the clamping bar, the setup piece in place, and why it is impossible to move the edge guide. If you have one, please tell me if this is how it is supposed to look, or if I am missing something. I got this for half price, as it was a returned item, and the person who had it first may have mis-assembled it.

For now, I have removed the springs, as it causes no issues with the clamping bar or the safety of the jig, and I was ready to cut my first box joints when a thunderstorm came up, so I had to run for cover and pack it in. I have looked at all three manuals that I have (¼" and ½" dovetails, and ¼" box joints.

As usual, TIA and all help much apprecieated.

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I don't have that jig but it looks very similar to the PC 4212 older model. I sure would like to see any pictures the owner's manual has. But for what it is worth, the side guides should not have to move much to get the side and ends in top to bottom alignment with one another. The bolt that you have the knurled nut on also clamps the template to the jig body. Put a piece of wood under the template. Place a playing card under each end to lift the template up a hair, specifically 1/100th of a hair. Tighten the nyloc nut to hold the template in place/ Wiggle the board and the playing cards out and you should be good to go. The locking bar has it own knob as you can see. For more details on a dovetail jig set up, see my book, Router Joinery Workshop. Or ask specific questions here illustrated with photos and I'll see if I can help.

That said, there are some DT jigs that don't work. I showed that at Burning Wood last year. Hopefully this is not one of them.
 
Thank you for that. YOu are right, but my problem was with the assembly of the parts that hold the front clamp bar on, and how they interact with the edge guides. The photographs in the manuals are not clear enough to see what is going on, and there are no instructions for assembling the clamp bar assembly. That being said, i removed the springs which seemed to be the cause of the problems I was having, and later today I am going to boldly try to cut box joints.

I'lllet you know...
 
The bar clamp assembly should not interfere or be dependent on the edge guides. Once the template and edge guides are locked into place, they stay that way until you change or move the template to accommodate different thicknesses of wood. The springs ought not to be a problem. In fact, they should help to keep the bar out to insert the next piece. To help keep the wood in place, I recommend you stick some PSA sandpaper on the inside of the bar. I use 120 grit. It helps keep the wood from slipping while you are tightening things up. Good luck.
 
Utter and complete failure, but I think I figured it out...

I tried to cut box joints today. It failed for two reasons AFAICS, 1> I was using ½" ply for a test piece, and it broke up, and 2> I was being a smartass, and tried to do two sides at once, and the left side slipped and failed to hold the workpiece properly. Lessons learned.

The problem I am having with the spring and the edge guide is probably because when you set up for a dovetail, you don't need the front clamping bar in place, so there is nothing to prevent proper setting of the edge guide. To set up for a box joint you do need the clamping bar in place, but the instructions don't deal with that. I'm going to give it another try, using real wood and doing one side at a time, and wihtout the springs when I am doing box joints. I'd go on to try dovetails, but I am determined to get the box joints right first. :mad:
 
The clamp bar is intended for use for both as far as I know. The edge guide sets the offset for both. The purpose is to cut an end and a side at the same time. And yeah, trying two corners at a time generally fails.
 
Not quite complete and utter failure

Well, actually I meant that when doing dovetails you don't need the clamp bar until after you set up the edge guides. With box joints you have to have the clamp bar holding the setup piece while you adjust the edge guides. Taking the spring out makes this possible. I found a little more information in the manual for dovetails. Apparently, I am setting up the clamp bar attachment correctly.

My next attempt was a little closer to correct, except that some enemy crept in and changed the depth setting of my router. :huh: This is the result. I was using a piece of red oak here.

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You can see that the fingers are too short, but they fit, more or less.
 

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Qualified success

I tried again, with the router bit set properly, and with sandpaper glued to the clamp bar as per Carol's good suggestion, so the piece wouldn't move, and came up with this:

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The fingers are not as clean as I would like, and I'm wondering if it may be a question of the quality of the router bit. I don't know it MLCS router bits are all that. I have a Freud spiral bit that I will try tomorrow. You can see that the fingers appear a little loose, although they seem to fit just fine. If this doesn't get better, I may go back to butt joints. :rolleyes:
 
Make a light pass just kissing the tips of the fingers, The corner of the dovetail bit will sever the long grain cleanly. Once those outer strands of long grain are cut then you can go back and do the heavy routing without tear out because the fibers that would tear out are already cut. I hope that makes sense. Oh, wait! You're doing box joints. Straight cutter. Well, same principle, But the very corner of you cutter would have to be pristine sharp. Just a light pass to get those first fibers sheared so they can't tear out.
 
a spiral bit will work better than a straight fluted bit for box joints, and a table saw jig like glenn bradley uses is very good at making box joints roger, as for DTails a jig of sorts is the easiest to use and if you could get a hold of one of the porter cable units you would be better off.. Carol this unit looks like a clone of brents..
 
You don't mean that HF mess! The template I saw in Roger's photos was not the same as Brent's clunker. But Brent has my PC model now.

But Roger, Larry is right. A spiral bit will give you much better results and that dedicated box joint jig Glenn showed is the cat's meow for making box joints. I think saw blades make better box joints than router bits, but then what do I know? :rolleyes: :D
 
Darn near perfect.

I tried again, this time with the spiral bit, and it seems to have made all the difference. As you see, the fingers are tight and square, and I'm quite happy with the result. I had to hammer the corner together, so maybe my spiral bit was a tiny bit smaller than the MLCS bit, but it is working. I lengthened the bit's reach a little, to allow the fingers to stand (as you Americans say) 'proud' of the sides. As this is a practice piece, I'm not going to sand it. It will just go in my firewood box, but I intend to make a decent box in the next few days.

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