Anyone know how to use a router table?

[Sunder]

Not the type that forwards internet packets, but the type that has a high speed cutting bit poking through the surface.

My one looks a heck of a lot like this:

I am trying to get a straight cut out of it, but here's my problem - the fence (Black wall at the back) only goes 2" back from the cutting tip, which means I can't use it to cut a width wider than 2".

The mitre guide (black thing to the left) slides and won't hold the acrylic still.

I am trying to make a custom battery box, but I can't get a nice smooth finish that they get at the factory - in fact, I can't even get it to cut a straight line.

My next thought is to remove the fence (and unfortunately that means the clear safety guard as well), and bolt on a plank of wood with 2 G clamps to use as a guide, but that seems quite extreme.

Anyone actually know the best way to get a good clean cut on a router?

 

[friedwires]

it sounds like you might be better off useing a table saw instead a router.

 

[dogman dan]

I would say table saw a rough but straight cut first. Idealy with a triple chip blade. Of course, you likely don't have the table saw, and triple chip blades cost a weeks pay.

So you end up doing this. Rig a guide to make a straight but rough cut with a skillsaw, 1/8 to 1/4 inch wider than your intended cut. Then rig the router table to trim off that excess. Your fence will be set to 1/8 or whatever you need on the feed side. On the discharge side, you use a shim that equals the amount you are taking off. So the work feeds in straight, and is supported by the fence on both sides of the bit. Go slow and easy, so you don't jerk the workpiece around feeding it in.

Do any final smoothing you need with a sander.

 

[dannyboyohyeah]

router tables such as this one are designed to have the cutting head's profile burried partially under the fence....so that you always are cutting the edge of the board (profiling it) that is against the fence. The adjustment (2") is to allow for wider cutting knives used with wooden spacer. These are not intended or recommended for any kind've ripping. Only for profiling.
If you are desiring a perfectly straight rip...best to make a ripping guide for your skillsaw...if you don't have a tablesaw. In order to accomplish this, you'll need a perfect straightedge, the length of your rips. First, cut a piece of plywood 3/8" or 1/2" that is of good quality...cut it 4" wider than the width of your skillsaw's bottom table (plate). Now, also rip a 3" wide piece of ply that will become your cutting guide, glued and screwed to the wider ply along one of it's edges. Lay it on there, and use the straightedge to make sure it is positioned perfectly straight as you screw it down. Also, make sure that your skillsaw's bevel angle is set at perfect 90degree cut (check with square). After the glue dries, you can remove the screws...especially if they are protruding abit through the other face.
Finding the perfect straightedge is the trick I guess....only GOOD quality ply has a nice straight edge these days...so that first rip cutoff may become the sacred piece to use as your straightedge.
Ok...so now you have a jig that is 1" wider than your skillsaw's tablebase. Carefully set your depthguage for the depth that will allow you to cut through your stock and add about 1/4" more depthcut than that. Mark this depth on your saw with magic marker so you can always find it when using this jig. (Many cheaper skillsaws will vary slightly in cutting widths as you raise and lower the depth). Carefully make your first cut through the jig's lower and wider piece of ply. Now you have it...that will ALWAYS be your perfect ripguide....just place the jig on your cutting stock...aligning it's edge with marks on your board (it is clamped to the board below at each end) and away you go. perfectly straight rips, with a skillsaw.
ps....I always keep a piece of the lower ply exposed behind the straightedge so that I can use small clamps that are tucked lower....this will allow your skillsaw to pass over the clamps without hitting, when it's depth is set deep and there's not much space to the saw's body. Good luck~~!!
If you need for me to send a photo, let me know...but I don't currently have one've these babies made up....but I've used them quite abit. They are really helpful. Another ps...when attaching your narrow ripping guide to the lower ply...use at least a 4' level as a guide to screw it down straight. Whatever the rigging guides' accuracy is...that will be every piece you ever cut with it.

 

[kriskros]

NEVER GET A WORK PIECE squeezed BETWEEN THE FENCE AND THE ROUTER BIT!!!....in that position the bt will be spinning away from you, 20,000rpm at a coup[le of hp and youve got a dangerous projectile .... for your application raise your STRAIGHT bit about 1/8"higher than the workpiece....bring the fence forward so that only about 1/8", or less, of the diameter of the bit is cutting...the fen ce is your guide... hold the work piece flat on the table and firmly against the fence... feeed the work INTO the rotation of bit... feed steadily at a speed that doesnt stall the bit or burn the worpiece...getting a feel for the right speed takes practice .... varies with the depth of cut ,router speed and hardness of the material... a router is the most usefull peice of equipment in a workshop... i have built roll top desks using router joinery...no screws or nails in the whole desk .....P>S> only use carbidetipped bits..cut cleaner,stay sharp longer and last MUCH longer tham high speed steel...good luck

 

[Sunder]

Thanks for the advice guys.

I'll try to dismiss the pieces of advice that I can't take. I'm sorry if you wrote something detailed that isn't practical for me.

Firstly, I can't go table saw. I actually went to buy a table saw yesterday. The basic model was $112, but had been on backorder with 30+ units waiting for 7 weeks. Every store within a reasonable distance drive was the same. I wasn't going to get it any time before Christmas. The next model up was $579, which I thought was too much, considering I'm buying it to build hobby parts - I'm not even a handyman, let alone a professional, which that unit was built for.

However, the guy asked me what I was doing with the table saw, and I told him. He said for smaller cuts, a router would be fine. Normally, I just ignore the advice of sales people until I've had it independantly checked out, but about 5 years ago, a mate of mine - an engineer, used a triton work bench with an inverted router to cut me 2 speaker mounts in 15 minutes from acrylic. A handful of very quick cuts, a drill in the centre to spin the piece around to round the edges, then to cut some 6" holes for the speaker. He made it look so easy, I thought it would be the right tool to do it with.

Reading these responses and another from a case modding forum, it appears my options now are the G-glamped guides, or freehand cuts using the fence to finish. I will be trying both with scrap later today, but have family events on for the next few hours. I do have one question which about 6 or 7 people have warned me about, but I'm still unclear: (I'm spatially challenged, it appears - when working on a bolt from the underside of my car, I always have to mimick the movement from above before getting back under the car to figure out which way I'm turning!). This is my question:

If I was looking directly down on the router table, do I feed from my left to my right, or the other way? If I needed to feed back and forth, do I feed from the back towards me, or from myself away from me?

Thanks.

 

[dogman dan]

Good question, but I'm not sure of the answer. Router tables suck so bad, I never used one one single time in 30 years of construction, trim carpentry, and cabinetmaking. Used freehand routers though.

On a real professional shaper, table saw, or planer, you feed the work with your left hand towards the fence, with your body facing so you are looking down the fence. Guess the idea is that the left hand could spare more fingers. :lol: I'm not sure if it's the same on a router mounted upside down.

But here is how to figure it out. A router or shaper bit is intended to cut down and into the work. Not cut from the inside to the outside edge, which would cause wood to splinter off. So if a router table works like a shaper table, the bit would be spinning clockwise.

 

[Thud]

Routational cutting tools are fine for cutting parts...you Just need to re-think the set up.

I would not use the inverted router set up in a table...too restricting for my taste (profesional wood worker/paternmaker/modelmaker for the last 29 years)
I cut conferance tables (boats,elipse's,trapazoids) using nothing but hand held routers for years. Large enough cnc's didn't become cost effective till the early 90's in the furniture industry. (since the average 16' table was still run on manual shapers for edge profiling)

Get your self a good straight edge (a pc of pywood works as well as anything) & a couple of clamps & you can use your router to cut to any line (or curve if your getting fancy) I would rather clamp my work pc down & handle the tool for controll. (the router has those handy handles )

I normaly guide off the edge of the base for straight line & very gentle curves. just measure form the edge of the base to the cutter & off set the cut line acordingly.

you can even use a cheap hand saw for roughing....like any hand tool, its the operators skill that will determine the end results.
good luck & show us your results.

Edit: i see i was a bit re-dundant after re-reading your last post router
to answer your question.
if your cutting a rabit on the edge of a board or a light mortise on a router table you would feed from right to left (cutter force pushing material into guide fence)

rippin on router with a long fence to trap the work is begging for:
#1 your finished part being pulled away from the fence by the rotational force of the tool
#2 having your part thrown in an attempt to hand feed a "climb cut".
(wood trapped between the fence & cutter really launches, we call it sudden catostrophic accelration in the industry)
the table is for puting some details on an edge, or non thru operations such as mortise work & such....that is a guide, not a rip fence.

 

[TylerDurden]

NEVER GET A WORK PIECE squeezed BETWEEN THE FENCE AND THE ROUTER BIT!!!....

+1
A router-table is not like a tablesaw, the work should not be between the fence and the bit. A router table fence is mostly for profiles on edges.

If you are cutting off pieces of acrylic in a straight line, score it and snap it.

If you are using a router for making irregular cuts, use a guide clamped to the work and not the table.


haha... Thud got in just before me. Still, you can't be too safe, uh... too careful.

 

[Sunder]

Okay, had a few more practice runs last night. Things I found:

1. Using a clamped square as a guide, feed from right to left to have the tool push the work piece against the square.

2. Using the fence to trim the edge, feed from left to right, to have the tool push the work piece against the fence.

3. Feeding at no more than 1mm per second (About 2.5inch per minute) gives the best finish - though I still get chips near the start and end. I am trying to steady my hand to avoid that. I've heard of people feeding at 10+ inches per minute as the "right" speed, but maybe they're using a different type of tip. I'm using a single flute, 4mm, tungsten carbide tip at 40k+ unloaded rpm. (Max speed on my 850W router).

Will simply have to keep practicing.

I'm actually thinking for my first box, rather than try to cut precisely and mount everything flush, I should over cut, glue precisely, then use a flush cutter to make the box look neater. I guess I'll experiment and see how I go.