Best way to cut mortises with OF1400
- Thread starter bdog01
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fpsnyder
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I'd use the MFT. You might be able to line them all up under the guide rail together and cut one of the four shoulders in a single pass. Then just rotate all of them 90 degrees, and cut the next shoulder, repeat. Does this make sense? WHOOPS! You said mortises...I'm thinking tenons. For mortises on 1-1/2" legs...where are the mortises? On the ends or on the faces? If on the faces (which would make sense), I would use the edge guide and sister up some wider material of the exact thickness next to your target piece for support. I suppose you could do the same with the MFT and then you could use the stops on the rail to make your mortises the same length. Though you would need to make sure that your workpiece is perfectly parallel with the guide rail. It would be a LOT easier to borrow someone's Domino for this task...it would take you a fraction of the time.
John Stevens
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If I had to use a router, I'd use a "right angle jig" like the one I discussed (and posted pics of) on this thread:
http://festoolownersgroup.com/index.php?topic=221.0;all
I have some pics showing it being used for this purpose, but the file size is too big to post here. I won't have access to the software I need to re-size the pics until Monday, but if you look at the pics I posted on that thread and use a little imagination, you can figure out how to clamp a leg horizontally with an auxiliary support beneath it.
I've all but gotten rid of the jig because I'm no longer interested in making joints with a router, but if you're interested in that sort of thing, a right-angle jig will enable you to make mortises, tenons and sliding dovetails. The only thing I would do differently would be to extend the top surface out beyond the clamping surface and cut a window in it, as Pat Warner does with his tenon and DT jigs. (A pic of one of Pat's jigs is posted in the thread I referred to above.)
The reason for this modification was that the guide rails of the router flexed just a little bit while plunging. While that did not affect the accuracy of mortises and tenons, it did cause a gap of about 1/100 of an inch to appear in sliding dovetail joints. It didn't affect the strength of the joint, but it was clearly visible to me, and therefore unacceptable if the joint was to be seen. That was a big problem because, IMO, the value of a sliding DT is cosmetic--if the joint is to be hidden, there are many others that are at least as strong but take way less time to make.
Hope this helps.
Regards,
John
http://festoolownersgroup.com/index.php?topic=221.0;all
I have some pics showing it being used for this purpose, but the file size is too big to post here. I won't have access to the software I need to re-size the pics until Monday, but if you look at the pics I posted on that thread and use a little imagination, you can figure out how to clamp a leg horizontally with an auxiliary support beneath it.
I've all but gotten rid of the jig because I'm no longer interested in making joints with a router, but if you're interested in that sort of thing, a right-angle jig will enable you to make mortises, tenons and sliding dovetails. The only thing I would do differently would be to extend the top surface out beyond the clamping surface and cut a window in it, as Pat Warner does with his tenon and DT jigs. (A pic of one of Pat's jigs is posted in the thread I referred to above.)
The reason for this modification was that the guide rails of the router flexed just a little bit while plunging. While that did not affect the accuracy of mortises and tenons, it did cause a gap of about 1/100 of an inch to appear in sliding dovetail joints. It didn't affect the strength of the joint, but it was clearly visible to me, and therefore unacceptable if the joint was to be seen. That was a big problem because, IMO, the value of a sliding DT is cosmetic--if the joint is to be hidden, there are many others that are at least as strong but take way less time to make.
Hope this helps.
Regards,
John
John Stevens
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Here's a pic as promised. The block of wood under the far end of the work piece is for support. There's a "stop" at the near end of the work piece. In conjunction with two stops on the guide rail, it allows the user to repeat the same mortise on successive identical work pieces. Edge-mortise 'til ya drop.
EDIT: The two round circles serve as a fence for end-routing the tenon, or end-routing a mortise in the mating piece if floating tenons are to be used. I left them there after finishing the end-routing because...well, just because on a jig that big, there's plenty of room to leave it set up for end routing and edge routing at the same time, just in case you need to go back and repeat an operation. Just for cheap thrills, I've attached a second pic showing the jig set up to rout mortises in the mitered ends of two work pieces simultaneously, a frill to have when working on pieces that are mirror images of each other.
Regards,
John
EDIT: The two round circles serve as a fence for end-routing the tenon, or end-routing a mortise in the mating piece if floating tenons are to be used. I left them there after finishing the end-routing because...well, just because on a jig that big, there's plenty of room to leave it set up for end routing and edge routing at the same time, just in case you need to go back and repeat an operation. Just for cheap thrills, I've attached a second pic showing the jig set up to rout mortises in the mitered ends of two work pieces simultaneously, a frill to have when working on pieces that are mirror images of each other.
Regards,
John
Brice Burrell
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John, you have some of the coolest jigs.
Brice
Brice
Hey John,
Do you find that the Festool clamps come loose somtimes? This morning I had somthing clamped down on the MFT useing three clamps, while I was tapping small finishing nails into the part that was clamped, the clamps popped off one at a time.
Are you having any problems with the router bit vibration and the clamps loosening off?
BTW i love that jig you made.
Mirko
Do you find that the Festool clamps come loose somtimes? This morning I had somthing clamped down on the MFT useing three clamps, while I was tapping small finishing nails into the part that was clamped, the clamps popped off one at a time.
Are you having any problems with the router bit vibration and the clamps loosening off?
BTW i love that jig you made.
Mirko
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- Mar 19, 2007
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Mirko,
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Mirko,
Sorry about the blank post my mouse locked up.
What I meant to ask was if you were using the screw style or the quick clamps. The screw clamps do come loose on me especially when really sanding heavy grits with the rotex.
Chris
Sorry about the blank post my mouse locked up.
What I meant to ask was if you were using the screw style or the quick clamps. The screw clamps do come loose on me especially when really sanding heavy grits with the rotex.
Chris
John Stevens
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Mirko said:
I never had any problems with the clamps vibrating loose while routing, sanding, or whatever, and that was one of the reasons I chose that method of clamping for the jig. Come to think of it, I'd been using a pair of those clamps to hold my benchtop table saw to a table top, and they were still tight as ever when I loosened them yesterday to move the saw for the first time in over a year. Maybe I'm just lucky?
This may sound crazy, but you may find they hold better if you clean the dust off them and then apply some light lubricant to the threads. "White Lightning" is a brand of petroleum-based wax in a fast-evaporating solvent: it's sold in bicycle shops for use on bicycle bolts, but equally useful around the shop. Lubricating the threads is standard procedure for bicycle bolts, because it allows the threads to slide against each other better as they're tightened.
Maybe if Greg Mann is reading this he would be able to say whether lubricating the clamp threads is a bad idea.
Regards,
John
John Stevens said:
So I'm now the resident expert on anyone with a screw loose? Well an observation or two from the professor: ;D First off, in John's fixture, the clamps are captured in an aluminum track, which I would think is an optimum circumstance. They should be aligned by default, making it less likely there is any skew that would allow the clamp to creep a little. Personally, I have not experienced creep on the MFT that I can recall. As far as lubing the threads; what this accomplishes is simply more squeeze with less torque needed. As an example, do you know that unless otherwise specified, torque specs are for clean dry assembly conditions. We have daily applications of some pretty high torque assemblies where I work, on the order of 538 ft.lbs on a 22mm bolts with 2.5mm pitch. The wrenches are six feet long. If we lube the bolt we will stretch the bolt, sometimes to the point of failure, before we meet that spec. I guess the inference I would draw to Mirko's question would be to lube the thread a little so that you can get more squeeze with the same effort. I would use a dry lube so that dust does not stick to it. I also doubt that the screw is backing down. As the clamp starts to cinch, a little wiggle to help seat it square might help. Of course this assumes you are not making a delicate clamping that would be disturbed. I also agree with Chris that the rapid style clamps may loosen but that is probably a function of the optimum pressure falling between the notches and being one short of really tight. Is that professorial enough John?
John Stevens
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greg mann said:
Everything you ever wanted to know about screwing, but were afraid to ask.
Regards,
John
