Basic Router Questions

[Paul Page]

I'm relatively new to using a router. I'm building a cherry half moon table. I've made a 3/4 in. MDF template of the top and am planning to use it as a guide for cutting the cherry top. I'm using a Triton 2 1/4 hp router with a flush trim bit.

So my questions are:

1. How much of an overhang should there be between the MDF and the cherry?

2. What size bit should I use?

3. What speed should the router be set at?

4. What direction should I go in?

Any other tips would be helpful.

Thanks,

Paul

[Prashun Patel]

You should make the overhang as small as is possible - between 1/16 and 1/8" is good. You want the trim bit to TRIM - not to have to remove a lot of material.

Assuming you're routing on the outside of the MDF (instead of in a hole in the mdf), you should route counterclockwise.

Note, however, that around corners, you can get chipping out, so either use a backing board or 'climb' into the cut just around the corners.

The wider the bit, the more stable the cut will be. Anything in the 3/8-3/4" wide range should be fine. The shorter, the more stable also, so unless yr planning to flush cut a lot of 2" stock, don't use a long one.

If you bandsaw or jigsaw fairly close to the line, flush trimming isn't a beefy operation, and you shld be able to run yr router around max speed.

Last, if you haven't bought yr bit yet, consider a spiral bit or at least one with shear cut flutes. It'll make for a cleaner cut with less tear out.

Be careful on the end grain.

[Tony Shea]

1. don't understand the question completely. The less material you have to remove the smoother the cut will be once the final pass is done. Get the cherry as close the the MDF template size as possible.

2. Whichever size you prefer. As long as it's a flush trim bit with the bearing in the right position (top or bottom). I'd say 3/8" or 1/2" but 1/4" or any other size will work for that matter.

3. What ever speed the bit is rated for. High speed for smaller bits and lower speed for larger diameter bits. It's dependent on the bit size.

4. The cutting blades of the bit should be going against the direction of stock feed just like any other blade. Table saw for example the teeth are running against the direction your feeding the stock. I believe that if routing the outside of a template that the router should be going counterclockwise and if your routing the inside of a template you should go clockwise. But double check this as I could be wrong.

The only peice of advise I can give is make sure you do not tip the router as your routing the edge as this will mess your cut up, which is pretty odvious. Others could probably give you a little better advise as there are some very talented artists/woodworkers here.

[Paul Page]

Could you please explain backing board and "climb into the cut"?

Thanks,

Paul

[Van Huskey]

Could you please explain backing board and "climb into the cut"?

Thanks,

Paul


He means using a piece of wood butted against the end of the cut so instead of cutting into the air you continue to cut wood past your actual top. Climb cutting would be going clockwise or left to right, the opposite of a normal router cut (chip cut), you don't want to do this over the majority of the cut since the router will try to pull itself through the cut instead of pushing against you.

Also call the table a Demilune if you want it to be more elegant... :D

[Greg Coleman]

One piece of advice I would give you is to put a continuous strip of painters tape along the edge of your template then route your first pass. Remove the tape and make another pass.

Cherry is notorious for burning. The tape will make your cut just a little proud. When you remove the tape you will only be removing a tiny amount of the cherry. Be smooth and consistent with this final pass. It will remove any burn marks created on your first pass.

[Troy Turner]

Looks like your questions are getting much the same response. One more I'll throw at you, how are you attaching the template to the cherry?

[Paul Page]

I was planning on clamping it.

Paul

[Don Morris]

Not sure how new you are to routers but just in case...Wasn't sure I saw a reference to the size of the bit. Whenever possible a 1/2" bit is normally preferred to the 1/4" bits for stability. Of course you're going to pay more for them, but that's the price of quality. Some small things can't be had in the 1/2" bit size. Be carefull of "climb cuts". They can "grab" the piece violently because your going in the same direction as the bit is turning. Normally your moving in the opposite direction of the way the bit is turning. When doing a frame for instance, on the outside diameter you would go clockwise around the perimeter. To go in the other direction would be going in a climb cut: dangerous, and extremely difficult to control. Remember, we won't believe you're doing the cherry thing unless you show us a photo of it after it's done. Happy wwing.

[Fred Belknap]

It might be a good idea to attach the template with double stick tape to keep the clamps out of the way. I think it would be a good idea to try on some scrap before attacking the real thing. Good luck.:)

[Bill Huber]

I would use double stick tape and I would get the tape form Eagle America, it is really good and strong but comes off with no left over sticky stuff on the wood.

Then you want to cut the cherry away all but the last 1/8 of an inch form the mdf, I use a band saw or jig saw for that.

I like shear type trim bits, they make very nice cuts and you get less burning with them. This is the one I like the best.
http://www.freudtools.com/p-176-downshear-helix-flush-trim-bits.aspx

[Rob Hough]

One piece of advice I would give you is to put a continuous strip of painters tape along the edge of your template then route your first pass. Remove the tape and make another pass.

Cherry is notorious for burning. The tape will make your cut just a little proud. When you remove the tape you will only be removing a tiny amount of the cherry. Be smooth and consistent with this final pass. It will remove any burn marks created on your first pass.

That is a great tip, thanks! I was having a problem with this on some maple the other day. If I wasn't moving fast, I was burning that stuff. Started driving me nuts.

[Troy Turner]

It might be a good idea to attach the template with double stick tape to keep the clamps out of the way. I think it would be a good idea to try on some scrap before attacking the real thing. Good luck.:)

That's where I was going with that. The clamps will have to be repositioned and you run the risk of maybe sliding your piece one way or the other. Even if just slightly, the router is not forgiving and will transfer that oops to your work. Double-sided tape or screws (if the holes will not show).

[Paul Page]

One last question (maybe) - should I do this on the router table or freehand? I have it clamped to a workmate, but in thinking about this I could actually screw the MDF and cherry together at some spots on the underside of the cherry that won't be a problem since it would be on top of the legs. I'm never sure of when it's better to use the table or not.

Thanks for all the help.

Paul

[Prashun Patel]

On a table of any size, I find it easier to feed a handheld router than to feed the wood at a constant rate. Also, my router table's not large enough to support a tabletop for flushtrimming.

[Troy Turner]

Freehand it. Screws would serve your purposes since you can cover then up. Even if it's on the underside of the table. Then you can clamp it to your bench or whatever you have. For future reference, if you're making a round top, you can make a jig to cut circles with your router (depending on how big you wanna go). You just use a centerpoint and make shallow passes.

[Dan Lee]

Think you got most of the answers. I would

cut to 1/16"

Router table

Double stick tape

Bit with top and bottom bearings this wiill allow you to cut half the profile with one bearing set up then flip the work piece and adjust for the other bearing. This ensures you are cutting with the grain and reduce chip out
http://www.leevalley.com/wood/page.aspx?c=2&p=51851&cat=1,46168,46171&ap=1

Like the tape idea on the template edge

[Mike Cutler]

You've gotten some really good advice, especially the tip on using tape on the template for the initial pass. I really like that one.Thanks Greg.

Pay attention to grain. If you are routing into the grain, on a radius you may experience grab and tearout. This is where climb cutting is your friend. That and on corners. Climb cutting is nothing to be apprehensive about, but you do have to pay attention. Keep the router moving and don't stop in one place.

[Myk Rian]

Bit with top and bottom bearings this wiill allow you to cut half the profile with one bearing set up then flip the work piece and adjust for the other bearing. This ensures you are cutting with the grain and reduce chip out
+1 on the top and bottom bearing.

[Jim Rimmer]

One last question (maybe) - should I do this on the router table or freehand? I have it clamped to a workmate, but in thinking about this I could actually screw the MDF and cherry together at some spots on the underside of the cherry that won't be a problem since it would be on top of the legs. I'm never sure of when it's better to use the table or not.

Thanks for all the help.

Paul
Freehand unless you have a really large RT. You don't want the top to tip.

[Eric Gustafson]

The last time I flush-routed to a template I used a few quarter sized dots of hot melt glue instead of double sided tape. I protected the work piece with 2" painter's tape and squeezed the glue there. I routed eight duplicates of my original template and found this method faster than double sided tape.

[Paul Page]

Thanks everyone for your suggestions. It's still a work in progress. I used just about everybody's ideas. Ended up doing it freehand. I've got to do something to the edges and then it's on to the shelf. Tapered legs, so it will be interesting.

Thanks again.

Paul

[glenn bradley]

Could you please explain backing board and "climb into the cut"?

Thanks,

Paul

Coincidentally I just came in from doing a backed cut. The backer was still in place so I just went out and snapped a pic. I was cutting a chamfer on the top edge facing toward the camera. The backer allowed the router path to continue past the right end of the cut.