You can use the trammel with a fixed-base router, but circle cutting is generally easier with a plunge router You don't have to flex and twist the trammel to keep the bit free of the work as you start the router. You don't have difficulty plunging die bit to start the cut. And changing the depth of cut between passes is easier to accomplish, too. So I'd recommend a plunge router.
1. Lay out the cut. Because the trammel has a nearly 2-inch-diameter pivot hole, it's dam hard to set the cutting radius using a tape measure. You need to lay out an arc of the intended cut. set the pivot base, and adjust the trammel to position the router on the layout line. You don't have to do the entire cut, just enough of an arc to set up the trammel.
So mark the center of the arc, which will be the pivot point, and scribe a bit of the cut arc.
2. Set up the router. To do this, select the bit for the job and tighten it in the router's collet. Next, set the plunge depth. Finally, connect the router to the trammel. You ean roughly adjust the cutting radius.
3. Set the pivot base. Because the pivot base is a square, it can be positioned accurately on a phot point. All you have to do is delineate the point with crosshairs penciled on the workpiece (and of course they m ust Ix: at right angles to each other). Align die base so each corner is on a crosshair line.The pivot axis will be exactly on the desired pivot point.
With the vacuum hose on the base's vacuum fitting, and the base properly aligned, pull the vacuum. The base will be firmly fixed in place.
4. Adjust the cutting radius. Adjustment of the cutting radius is accomplished by loosening the locking knobs on the adjustment bar. Then the router can be moved in and out in relation to the pivot.
Hook the pivot plate over the base's pivot collar. Plunge the bit to the surface of the workpiece (with the router switched off, of course). Loosen the locking knobs and move the router in or out as necessary to align it on the laid-out arc. That done, tighten the locking knobs, plug in the router, and you are ready to cut.
To mount the trammel on the pivot base, hook the pivot plate around the vacuum hose, as shown, and settle it onto the pivot collar.
5. Rout the arc. Switch on the router, plunge the bit about '/» inch into the work, and feed the router counterclockwise. If you are cutting completely through the work, plunge the bit deeper at the end of the first lap, and make a second lap. Always feed the router counterclockwise
To set the pivot base, scribe crosshairs on the workpiece. marking the desired pivot point. Line up the corners of the base on the lines, as shown, which will place the axis of the pivot collar directly over the desired pivot point. Turning the valve on the vacuum pump will pull the vacuum, sucking the base to the work.
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You were a geek in junior high school, weren't you? Come on. admit it. In the cafeteria, you'd impress your friends by sucking a drinking cup onto your face. You'd hold it over your chin and mouth and suck all the air out, and it'd just hang there. Oh, man! Don't you remember how impressed thev all were?
Well, now you can impress your woodworking friends with a similar bit of magic. Use vacuum pressure to hold a workpiccc while you rout it.
"Gee, Mr. Wizard," you're saying just now, "what's the trick?"
No trickery, just simple science. The woodshop principle involved is the same one that prevailed in the junior high cafeteria. Remove the air between the workpiccc (that cup) and the workbench (your face), and they will stick to each other. let the air seep back between the two, and they separate. In the workshop context, it's usually callcd vacuum clamping.
Look at the most straightforward vacuum-clamping device, the vacuum plate.The plate is a thick board with a hole drilled through it. A vacuum hose is inserted into the hole.Then special tape is applied around the perimeter of the board, forming a very shallow recess. You lay the work-piece on top of the plate, completely covering the recess and turning it into a "chamber." Suck the air out of the chamber, and it becomes a vacuum chambcr. Allahkazam! The workpiece and the plate will be stuck together.
Because you don't need C-clamps or hand screws or any other mechanical clamps to keep the two pieces bonded together, the router's got a clear pathway to do its work. In this regard, vacuum clamping is in the style of using carpet tape, hut it doesn't require you to prv the pieces apart with a chisel when you are done, and it leaves no sticky residue. Consider these possibilities: You can make
• a plate to hold a workpiccc in place on a bench (on the horizontal or vertical) so you can rout dadoes or gn>ovcs into the surface, or rout a profile on the edge;
• a T-square that attaches itself to the work without router-obstructing mechanical clamps:
• fcatherboards and other hold-downs that attach themselves almost instantly to a router tabic (or other power-tool worktablc);
• a trammel whose pivot attaches to the work without j nails, screws, or sticky tape:
• templates that stick firmly to the workpiece or that hold the work tight to a bench, leaving the edges unob-structcd;
• push blocks that pick up and hold a workpiccc until you arc ready to let go of it.
This is a pretty intoxicating variety of vacuum-clamping ! jigs. And 1 repeat that you make them yourself, customizing | them to your job, your tools, your work habits. You do have to be selective about the materials you use for the jigs, and you do have to buy some special equipment.You can't make the device that produces the vacuum, for example: you have to buy it. You need to buy "plumbing" to link the vacuum
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There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.