Router question

[shmokes]

I've just finished cutting out one of my side panels.  My plan is to sand the edges and make the rounded corners nice and round -- I stuttered a little with the jigsaw so they're currently more like rounded edges from, say, Virtual Fighter 1 -- But once I've got it perfect I was planning to clamp it down to another board and use it as a router guide to cut the other one out so they will be exactly the same.  Here's my question:

Are flush trim bits okay to use in the same way one would generally use a straight bit?  My straight bits have no guide bearings on them and I don't have, nor do I know how to use template guide bushings.  I do have a 3/8" flush trim bit with a guide bearing, but I'm afraid that it's made to cut trim rather than 3/4" melamine.  Is there any validity to my concern?  Should it be fine to just cut it in a couple of passes or should I perhaps do it in like five or six passes just shaving off a thin layer with each pass?  Or should I bite the bullet and buy more equipment?

[HeadRusch]

I'll go one better:

Are the sub-$100 routers from Lowes/HomeDepot acceptable??  Reason I ask is because the Router is the one tool that eludes my comfort zone.

I received a router from a relative but its missing its guide, and so its like this flat router with a bit..and I'm like "this thing will kill me if I try to use it"....so I'm thinking of buying a router for my own.  However I'm not sure exactly what kind to get.  

Routers are basically Milling Machines, aren't they?  You set up a jig or use the routers edge guide to determine how far "in" from an edge (if you are doing an edge) you want the bit to cut in, and then you set the depth of the cut itself, yes?  If you're just routing out material from an inner section thats referred to as a plunge cut and you're looking for a flat-ended router bit in that instance....(yes???)...

I hate to piggy back this question on Schmoke's inital question...but I figured if you can kill two birds with one stone.....

[shmokes]

You're pretty much correct about all your impressions of routers.  The plunge cut would ideally be done with a plunge router, but can easily be accomplisted with a fixed-base router.  If you are going to put a recess in the bottom of your control panel to mount a joystick in for example you can just drill a hole into the spot where you're going to recess that is big enough in diameter to slip the router bit into and deep enough that the base of the router comes into contact with the surface of the wood.  Then you can begin routing as though it were not a plunge cut, since I guess it is no longer a plung cut...  Also, if I am not mistaken (and I very well could be as I have only just used a router for the first time last night) you would generally want a fluted bit rather than one that was flat on the bottom for a plunge cut.

I hope that made sense.  

Edit (this next part is kind of long, no need to read it if you aren't new to routers):  

By the way, since I just used a router for the first time last night I am in a unique position to give you my first impressions.  It was far easier to use than I expected.  Simple to control and gave EXTREMELY nice results.  I wasn't using a real big router (1 3/4 HP).  The only thing I would tell you (as I had read so I was prepared for this) is that when you first turn it on the motor instantly wants to spin that little bit 20,000 - 30,000 RPM's.  In actuality, though, the motor would just as soon spin the unit and have the bit stay where it is, which it tries to do (a combination of both really).  So for about a tenth of a second when you first turn the router on it will give a pretty good jerk counter-clockwise, but then it becomes smooth and you could easily hold the router with only one hand while it's running as it no longer requires any force to keep it steady (not recommended -- always keep both hands and both eyes on such a powerful tool if it's on).  The jerk is really not too bad, but would startle you pretty bad if you weren't expecting it.  The power switch on mine is placed within reach of the handle so I have the luxury of having both hands on the machine when it does this, but it shouldn't be too bad even with only one hand -- just be aware of it.  Also, DO NOT use a router without a dust mask (and goggles obviously).  You don't need anything fancy, just a cheap $2 thing from ACE or Home Depot.  You have to see how much ultra-fine saw dust these things make on even the smallest cuts to believe it.  You don't want to breath that stuff in.  For the same reason don't even think about just laying down newspaper or something and making cuts somewhere like a living room or kitchen.  You will never, EVER, be able to clean up all the dust.



So....anybody possibly have the answers to my original post???  

[mpm32]

You want to use a pattern cutting bit.  One with a top bearing would suit your purpose better. Like this;

http://www.mlcswoodworking.com/shopsite_sc/store/html/smarthtml/pages/bt_patrn.html

Use the first piece as your pattern, trace the new piece with a pencil.  Use your jigsaw to rough cut the new piece approx 1/4" outside the line.  Clamp the pattern piece on top of the new piece, and use your router with the pattern cutting bit to clean up the cut.  You could use just the router to cut the piece initially but it will take longer and your bit will last much longer if you do it as I described.

[Wienerdog]

You want to use a pattern cutting bit.  One with a top bearing would suit your purpose better. Like this;

http://www.mlcswoodworking.com/shopsite_sc/store/html/smarthtml/pages/bt_patrn.html

Use the first piece as your pattern, trace the new piece with a pencil.  Use your jigsaw to rough cut the new piece approx 1/4" outside the line.  Clamp the pattern piece on top of the new piece, and use your router with the pattern cutting bit to clean up the cut.  You could use just the router to cut the piece initially but it will take longer and your bit will last much longer if you do it as I described.

You can also use your flush trim bit.  In this case you are using your 3/4" piece as your template, so if you compare a 1" flush trim bit with a 1" pattern bit, it won't make a difference.  With the flush trim bit the template goes on the bottom, with the pattern bit the template goes on the top.

Next time, or even this time to make it easier for yourself, cut a template on 1/4" fiberboard.  Cut it with your jigsaw and then sand it down to exactly how you want it.  Then use that template to cut your two panels.  Just think about that tonight while you are trying to sand 3/4" melamine... lol.  I've made that mistake many times.  1/4" fiberboard sands like nothing and it is very easy to shape (also not that durable, so be gentle with it).  Oh, you can still use either bit, but the template bit is easier when you are using a 1/4" template like this.  If you use a flush trim bit, you have to set the depth of the router to 3/4" plus the width of the bearing.  I've done it before, but it's a little more work.  If you don't do much of this type of work, I would just use the bit you have and spend the extra time adjusting the router right.

[ErikRuud]

You cand use the flush trim bit.  There is no need to go and buy a pattern bit if you already have the flush trim bit.

I used a flush trim bit on mine with no problems at all.

When you get your first side sanded smooth, lay it on top of the next piece to be cut.  Trace the outline with a pencil.  Remove the first piece and then rough cut the second piece so that it is about a 1/4 inch to large.  Clamp the first piece onto the second piece. Make sure the good piece is on the bottom, and then trim away.  The rough cutting will save a lot of wear and tear on your trim bit.

[HeadRusch]

Great replies, great replies.

Question: the pattern-cutting bits have the bearing on top as that is what "rolls" along the edge of the pattern while the bit cuts the stock beneath the pattern, yes?

If you dont use one of these bits, you must then use either a self-made jig, or whatever guides your router might come with......yes?  The router sits on the stock and you use your guide or jig to stay on track/straight line...yes?

[ErikRuud]

HeadRusch,

Yes & Yes.

A pattern bit has a bearing on the top that rides against the pattern and makes an exact copy of the pattern.

A flush trim bit has the bearing at the bottom the rides against the pattern and makes an exact copy of the pattern.

There pattern bushing that ride against a pattern, but usually the pattern needs to slightly smaller (or larger if the cut is to the inside of the patter) than the finished piece.

You can also make a pattern for the edge of the routers base plate to ride against.  This pattern would need to be quite a bit smaller(or larger) than the finished piece. You would need to measure the distane from the edge of the base plate to otermost edge of the bit to find out how much smaller to pattern would need to be.