Pattern routing -- what went wrong?

Hard to say for sure since your photos aren’t coming up, but from your description I’m guessing the problem is the word untrimmed.

When pattern routing, the blank should be trimmed with a bandsaw to the approximate shape so that you are not taking off too much material with the router. Trying to take out large chunks of material with a pattern bit will result in grabbing and tearout.

-- Charlie M. "Woodworking - patience = firewood"

Try taking smaller passes and not all at once.

The piece could have also had a crack already.

Also pay attention to the direction your router bit rotates.

-- Gary, East TX -- The longest journey begins with a single step.

what He (Charlie) said. also good for your router bit as it’ll prolong it’s life as it doesnt subject it to heavy impacts, and make it take light passes, and obviously less material to pass by it’s blades.

compare that scenario with a jointer… now consider that you’d lower the infeed table to 2” below the cutterhead (theoretically).

you can argue that you’re taking light passes each time. but it only takes 1 bite of the bit to grab onto the wood deeper, and it’s too late.

-- When in doubt - There is no doubt - Go the safer route.

i would also add insted of clamping your pattern or templet to the piece use good double sided tape to keep it from moving

-- I buy tools so i can make more money,so ican buy more tools so I can work more, to make more money, so I can buy more tool, so I can work more

All good approaches besides destroying your work its dangerous not to due what Gary,Charles,purp and doyou said

-- Jim from Heirloom Woodshop, custom furniture ,maker, woodworking school, heirloomwoodshop.com

Definitely trim to within 1/16 or so of your line, but one thing which has not been mentioned is grain direction…..make sure you are routing downhill….sometimes that means switching bits from top to bottom bearing or vice versa…..

JC

-- Somewhere, something incredible is waiting to be known. -Carl Sagan

what Gary said is crucial, your router bit is rotating AGAINST the wood fibers.

-- Francisco Luna, San Francisco Bay Area.

i see some bandsaw marks ? that is good to remove as much stock as possible leaving cut proud ( over ) by
1/16 to 1/8 then use router .
it also appears that you routed 1 side and then put pattern on other side to compleat ?
. a router bit spins in a clockwise direction when held by hand looking down ,
but upside down in the table it spins counterclock wise . if you clamped your pattern to the piece you could not get it close enough to the end because of the table . when you route curves ,youhave to watch for grain changes .
climb cutting is when you have to push the router into the work ( prefered) and downhill cutting , when the cutter wants to pull itsef along the work ( this is not good , unless under firm control ) .
the chip that broke was because the bit was climbing across the grain , and at the end it broke the wood with no support . 1, shape ends first and redimension to remove splinters
. 2. make multiple passes with bit a little at a time
. 3. clamp sacrifice board on sides for bit to follow , then remove
. 4 attach patern with nails / screws and fill holes later .
.
personaly i hate working with oak for these reasons and it also splinters in my hands , i hope i didn’t confuse to much , im getting tired and grogy . good luck and safe woodworking

-- david ,new mexico ,allheart

Sounds like I’m going to have to get another bit—I’ve got a top-bearing 2” bit (the feet are 1 1/2” wide) and I guess my jigsaw could get me pretty close to the layout line since I don’t have a bandsaw yet.

I strongly believe that the chip that broke loose (but not completely detached) from the top can be glued back into place—is there a good way to get glue in there without further damage?

There really is a lot to remember—thanks all for not making me feel like a moron!

(I tried to figure out how to paste in the photos from Flickr but I couldn’t for the life of me get them to embed. And I’m a software engineer by day!)

-- Bret, Colorado

Just squeeze the glue in there. It doesn’t have to get all the way in just as much as you can. Then clamp it for a couple of hours.

-- Gary, East TX -- The longest journey begins with a single step.

Okay. I repaired the damage and got some carpet tape at Home Depot to affix my template to the block. Took my jigsaw out and trimmed the foot close to the template. Re-routed the damaged side using a pattern bit instead of the flush trim bit I used on the other side. Worked like a charm.

Then I went to remove the template and realized that the carpet “tape” I had wasn’t tape at all—it was a thin layer of rubber cement-like substance with some fibers in it for structure. I got it all off the template, but does anyone have any ideas how to get it off the workpiece without damaging it? I thought about goo gone and other solvents but wasn’t sure whether they’d damage the wood. I tried using a putty knife to scrape it off and that didn’t work so well. I tried rubbing it off and that kind of worked, but I was concerned that I might be forcing something into the wood that would interfere with later finishing.

What would you all try to get this gook off? (I’ve ordered some proper double-stick tape from a woodworking supplier online and will be using it, not the carpet tape, in the future).

-- Bret, Colorado

try mineral spirits ( let it work for a bit ) then sanding ?
we learn patience in woodwoorking .
don’t teach the wood ,
let it teach you .

-- david ,new mexico ,allheart

First I would try mineral spirits then denatured alcohol after that maybe acetone.

-- //FC - Round Rock, TX - "Experience is what you get just after you need it"

...and don’t forget to use your scraper, it’s the hand tool gem of the shop!

-- Never board, always knotty, lots of growth rings

usually most of it just peels off, and if any goo is left – a scraper will take care of that without damaging your piece (on the contrary – it’ll leave it glass smooth)

-- When in doubt - There is no doubt - Go the safer route.

The scraper worked like a champ. I hadn’t gotten around to picking one of these up, but a quick trip to Woodcraft and $15 solved that dilemma.

Thanks!

-- Bret, Colorado

I was unable to bring up ypur photo’s but it sounds like you were trying to remove too much material at a time. A patternmaker’s bit needs to be no further than a eigth of an inch from the pattern (I prefer A sixteenth) and you can get there with a bandsaw or a jig saw. Also when you get to the end grain, you might need to “back rout” to prevent tear out.
Good luck,
Kimball

Did you have the same side of the piece against the table for both cuts? If so, when you did ‘the good,’ the counterclockwise rotation of the bit (as viewed from above down on a table-mounted router), you were making cuts that went from the middle of the piece out toward the end, slicing through the grain, but not lifting it. If you flipped your pattern upside down, clamped it to the other side, and tried to cut that side for ‘the bad,’ now your cuts were chopping from the edge of the board toward the middle, lifting up the grain, tearing pieces away. It shouldn’t happen if you flip the piece over, so the right side is now on the left, and the opposite face is against the table, as now you’d be cutting it the same was as ‘the good,’ over on the right, with the router bit making slices through the grain without lifting it.

That’s my guess. Did it make sense?

-- Gary, Los Angeles, video game animator

I thought I would add my 2 cents worth here on pattern routing..I know exactly how you feel when the cutter grabs the piece.. I have it do that to me at times when I’m coming around to the end grain of the part.. so I feed it backwards.. hard to explain.. as for attaching the template to the piece..I used to use double stick tape for years.. would have tape residue all ofer the floor at the end of the day..So when I started to ask others how they got their templates to stay on the piece..Sam was actually the one who told me how he does it in his shop.. he nails it on with small 7/8 brads then just fills the tiny holes.. I check his work out and could never find the holes..LOL he uses 3 or 4 brads depending on the length of the template.. I started to do this also and it’s been faster.. no mess or tape to scrape off and it works well.. but we also shave our pieces to within 1/6th of the final line of the piece and then use the shaper with a spiral cutter to finish it off.. hope this somehow helps.. if not..I’ll be quiet now..LOL

-- Randall Child

HEY WAIT!!! if that’s you in the picture by your name.. you stay away from routers!! does your mom know your playing with your dad’s tools like this?? LOL

-- Randall Child

Ha! No, that’s my son, Ben. He’s much better looking than I am.

I’m now switching the bit halfway through the piece and flipping it over. Bit of a pain since I have only one template, though I supposed I could use that one to route several more and then each blank would get its own template. It’s working much more smoothly this way.

-- Bret, Colorado

Ok.. now I gotta ask you.. is the guide bearing for your trim bit on the top..or bottom of your cutter? if it’s on the bottom.. you don’t need to flip the pattern over..since you routed the lower half of your piece already and it’s flush with your template..just raise the heigth of the cutter and the bearing will roll and use your piece as it’s guide

-- Randall Child

Bret
Looking at your photograph I see that you are feeding the material into the router bit inserted in the router table and removing the full height of the material. You are obviously working with a ‘male’ template. My suggestion is to make a new template ‘Female’ and rout with the aid of template guides. This way you can take small cuts and produce a better surface.

Have you ever considered the use of Guides (Guide bushes)?

-- Getting more from my router with the aid of Template Guides

I’m not sure how to build a female guide for this particular piece, or maybe I just don’t understand what you mean by female. The guide I’m using is the exact shape I want the finished piece to be. I’m using a piloted bit (two, actually, one top and one bottom-piloted, and I switch bits when I flip the workpiece. Even after trying to make a close trimming cut using my jigsaw, I still try to make multiple, thin passes on the router table now so that I sneak up on the template rather than trying to get there all at once.

I thought about guide bushings, but don’t have any yet. Would they take the place of the bearing on my bit, allowing me to use a single bit? It seems like the bit would have to be removed to change the guide bushing, which seems like it would take more time than what I’m doing now. I’m not opposed to taking more time, as long as there’s a tangible benefit. I guess I just don’t see what that benefit would be. Can you enlighten me?

Thanks!

-- Bret, Colorado

Oi! And I missed that you were an Aussie. I lived in the Alice for almost 5 years, just returned to the US back in 2006. My wife (also American) keeps bugging me to try to find a way to go back again, so I may be returning one day. It’ll be a good excuse to go shopping for all new tools rather than trying to rework all the motors for new voltages.

We really enjoyed the few times we made it over to the west coast—Margaret River, Broome, Perth, Freeo. Is Little Creatures still brewing in Freeo?

(Sorry for the off-topic post!)

-- Bret, Colorado