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Forum topic by Coleby posted 04-13-2014 08:21 AM 905 views 0 times favorited 9 replies Add to Favorites Watch
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Coleby

29 posts in 1634 days


04-13-2014 08:21 AM

Topic tags/keywords: question router shaping arts and crafts

I want to build multiple car shaped beds for the familiy. I have a template for the side profile and want to know if there is a safe affective way to simply lay the template on top and use a router to cut the shape in one pass. Its 3/4” birch. I want to avoid using a jig saw and then flush trimming. This would save me an significant amount of time but what are my Options??

Thanks

Jonathan Dean

-- Dean, http://www.woodworkerColeby.com


9 replies so far

View Whiskers's profile

Whiskers

389 posts in 871 days


#1 posted 04-13-2014 01:14 PM

Yeah, this one is easy, you want a pattern bit. A pattern bit is a straight bit that has a bearing on the top or bottom that rides along another piece you do not want to trim, and cuts the part above or below it. Be sure to put a little light oil on the bearing before starting. Just use a jig saw to sloppily rough cut your sides a little larger than you want. Clamp or screw your template to it, than go at it with the router to trim it. Tricky part is getting that first piece cut just right and perfect to be the pattern. One way to approach that problem is to cut as close as feasible with your jig saw, being extremely careful not to undercut anything, overcutting a little is allowable. Than use a oscillating spindle sander to sand the edges into final shape. Much easier to sand to a line on a sander than to cut to one with a jig or band saw.

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JesseTutt

853 posts in 955 days


#2 posted 04-13-2014 01:31 PM

Make sure you attach the pattern piece to the plywood to be cut. Screw it in areas that will be cut away or use double sided tape, or both.

If you mean that the pattern is a piece of paper, then attach the pattern to a piece of 1/2 inch plywood and cut and sand the plywood to be the correct shape and then adhear the plywood to the wood to be cut.

-- Jesse, Saint Louis, Missouri

View Lee Barker's profile

Lee Barker

2169 posts in 1695 days


#3 posted 04-13-2014 03:18 PM

You won’t cut the 3/4 birch in one pass. Probably about 5. It’s still a great way to get what you want.

You’ll need:
A middle line router
A 1/2” shank top bearing bit
A sacrificial piece of something underneath…

And a large container for the chips!

Kindly,

Lee

-- "...in his brain, which is as dry as the remainder biscuit after a voyage, he hath strange places cramm'd with observation, the which he vents in mangled forms." --Shakespeare, "As You Like It"

View Shawn Masterson's profile

Shawn Masterson

1262 posts in 793 days


#4 posted 04-13-2014 04:13 PM

spot on lee I would say 4-5 passes. On the other hand with an good saber saw blade you could cut it within an 1/8” of the line and just flush trim it in 1 pass. I think the saber saw and flush trim will be faster with a cleaner end product.

View ChefHDAN's profile

ChefHDAN

513 posts in 1694 days


#5 posted 04-13-2014 04:26 PM

Coleby, Lee is right on the money, with the how too, but if you’re looking to save time, then the jigsaw cut and flush trim is the fastest method since you can flush trim in 1 pass if you’re just cleaning up an 1/8” off the edge, and you’ll have alot less mess to as Lee points out.

-- Sssshhhh, I'm pretending to be working

View NiteWalker's profile

NiteWalker

2710 posts in 1421 days


#6 posted 04-14-2014 04:59 AM

”I want to avoid using a jig saw and then flush trimming.”

You’d lose any time saved not sawing close to the line from having to take multiple passes as Lee mentioned.
Jigsawing close to the line, then flush trimming is the fastest method.

-- He who dies with the most tools... dies with the emptiest wallet.

View JaySybrandy's profile

JaySybrandy

78 posts in 421 days


#7 posted 04-14-2014 09:10 AM

how many are you going to make because I would just jig saw the flush trim in needed to

View Jim Finn's profile

Jim Finn

1847 posts in 1766 days


#8 posted 04-14-2014 03:08 PM

I would saw it then rout also. I would use a hand held jig saw with a metal cutting blade to reduce the amount of splinters caused by this cut.

-- In God We Trust

View bigblockyeti's profile

bigblockyeti

2041 posts in 565 days


#9 posted 04-14-2014 04:13 PM

I cut 3/4” plywood in three passes before and wouldn’t recommend doing it with any less. This was also done with a 3/8” bottom bearing bit so only 3/8” is being removed and the bit is not necked down between the router and the cutting edges increasing the chance of a broken bit when being overfeed. Precutting with a bandsaw or jigsaw and doing a final trim with a bit would greatly reduce not only the mess, but the strain put on the router and cutting bit.

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