Cutting Bodies By Router

[demonx]

I've tried this several times. Always get tear out if I use too big router bit. I eventually gave up and went back to hand cut/file.

I had tried different feed directions, working different curves of the body at different directions etc. I'd be going great then RIP and the body is flying through the air !!!

I've recently jumped back on the horse after buying a 5mm long router bit, works a treat, no tear out -but I have to do so many passes it's not funny.

So who here uses routers to cut and what are your experiences, secrets, tricks of the trade? Also what bits are you using?

[dpm99]

Wait - Are you rough cutting with something else first? I've typically rough cut with a jigsaw and then finished it off with the router. However, I've recently moved to the RoboSander, to avoid tearout.

[curtisa]

I'm using a router at the moment, but only by necessity as I don't yet have a bandsaw. Currently I'm using a two flute 19mm dia flush trim bit which has down-shear cutting blades. I find that the worst spots for tearout are around the tips of the horns and inside the cutaways. Usually I can minimise any nastiness by applying more downwards pressure on the workpiece and doing several lighter passes as I approach these areas on the router table (maybe compensates for less mass in the timber at those skinny points, less chance for chatter leading to the bit munching into the wood?), but I suspect that you've got a more sensible approach using a shallow bit in multiple passes. Any tearout I've had thus far has been manageble with a bit of careful sanding to reshape the affected area.

[jeremyp]

my advice (and I should listen myself haha)

prep work, don't try to cut more than the blade can handle, less than half the width seems to be a rule, some for 1/8. also good templates. I like atleast 1/2" thick templates for routing with

use multiple cuts, depending on the grain orientation you may need to approach the curve a certain direction. somewhere on stew macs site is a diagram of which direction to route from to avoid kicking and or tearout.

slow down! routing is fast but don't rush it, you just make mistakes. if you take your time, you probably won't mess up and have to start over (trust me I know)

practice!

this is

[Juntunen Guitars]

Don't take more than 1/32"-1/16" in a pass and you will almost never have tear out unless there is a defect in the wood. I like using routers with a half inch collet instead of a quarter because they can handle more.

[pauliemc]

Typicaly I use the band saw to rough cut the outline first. I try to get it about 2-3mm away from the marked body outline.

then attach the template & start to clean the edges with a hand router. I would not even bother to start routing unless i was almost right on the 2mm mark with the rough cut shape. The more you have to cut with the router - the easier it is to fook it up.

Go realy REALY slow aswell. Iv seen guys try get a strat profile cut in about 10 mins flat & they always end up as paint grade bodies with loads of fookin filler.

take yout time & only remove tiny amounts as you go. Friend of mine once told me to think of my router as a plane. thin slices is the way to go

Also. get the hardest cuting head you can & replace it often. they dont last, even carbide bits only get me 5 bodies Max.

[demonx]

Pauliemc:

Everything you wrote described how I did the last one, which was a success, however I just thought I was over thinking it all and was pretty sure everyone else must have a "better way" - apparently not!

Cheers

[dpm99]

Learning to do it correctly with the router is probably best, but then again...

http://www.luthiersfriend.com/robosander/robosander.html

[demonx]

I glued some scrap bits of Maple, Mahogany and Alder together yesterday so I had a bash this morning at routing.

I made six passes all up.

This is the only tear out I got which is a bummer, but it's minor and this guitar will be painted solid:

[curtisa]

Yep, that's exactly where I had my last mishap.

[verhoevenc]

Chris

[demonx]

Verhovenc: sure that easy section turned out fine but how many have you ruined trying it in one pass? (I'm nit attacking, just researching)

I've got a large big like that (not tapered) and I'm just thankful I still have my fingers.

I wonder if the taper makes much difference. If it does then the spiral cut bit should make one pass cuts even more pliable.

[verhoevenc]

Ruined= 0. Tiny bit of tearout= 1. Successes? More than I can count. I've ruined WAY more wood with big roundover bits, doing stepped cuts with smaller bits on a 1/4" shaft.

The shear cut makes a large difference. It means that that entire blade isn't hitting the wood at one time, so it's less jarring (which is one of the main reasons you get tear out). Yes, a spiral bit would be great too... but this works just fine and is a lot cheaper than I've seen spirals this size. This one's also a heck of a lot easier to re-sharpen (although I haven't had to yet and have done a good number of bodies with it).

Routers are one of the best tools you can use for electric guitar work, but like I told a friend of mine when I was showing him this, you can't be afraid of it! Respect it by all means, but don't be afraid. You need a firm grip, a smooth hand when coming into a new cut, etc. If you're scared, you won't have those and it'll grab and throw; any bit.

The other big key here, and I can't stress this enough, only leave about 1/16" to MAX 1/8" outside the template for the router to cut off!!! THAT is the biggest saver of tear out I can give. Don't make your bit do too much work! That rule applies to ANY bit. This big one, small ones, anything.

Oh, and don't waste your time with crummy bits. Stick with the quality names you trust. I go white-side and nothin' else.

Hope this helps,

Chris

[pauliemc]

+1 to everything Verhoevenc says here.

But I would add, the taller bits are great if you have a sturdy router table. 1/2 inch caul. If you are using a hand held router or a smaller table (1/4 inch caul) stick to the more shallow depth bits.

On some timbers like ash or sapele, I cut with 3 passes even if I am on the table with a tall bit. Overkill, but worth it with some of the more brittle timbers like sapele.

[verhoevenc]

Yeah, probably should have mentioned that this is a STURDY ROUTER TABLE method; as can be seen with the solid cast iron extension I'm using on my table saw.

Chris

[MiKro]

Router table = more control. A router table is not hard to build and will give you much better results. You don't have to have the latest and greatest, just a functional sturdy one.

Also remove as much wood with a bandsaw, rasp, even a jig saw with a good blade will work just do it slow with a jigsaw. Anything more than 1/8" is a problem and waiting for it to grab, preferably about 1/16". Good router bits, NOT cheapOs

I use CNC now, much easier but also harder from a learning curve standpoint and cost. I still use my router table though as somethings are just easier to do and faster than setting up for the machine.

[demonx]

I have a tritan router table. Not top shelf but gets the job done. My body template is 6mm thick plexiglas. I've always cut as close to the line with the bandsaw as I can first so the router is basically just cleaning up, but when it grabs it still tears.

After your comments I'm considering ordering the full depth carbide spiral bit and attempting single passes again.. From memory I think the one I was looking at is around $75 but it's prob been twelve months since I enquired so I'll need to look into it again.

In response to being scared of the router, if you don't give it the respect it deserves then you're crazy. A guy I work side by side with every day at the factory is missing a finger from a router table grabbing and pulling the timber at his previous job as a woodworker. Every time he points his stump it reminds me to respect the router.

I use a safety grip/handle to push the timber into the table and into the blade while my second hand steers.

[verhoevenc]

Notice I DID say respect it, but DON'T fear it. You NEED confidence when working with it. Respect involves knowing your tool and what it does. Watch the video carefully, and watch where my hands are. My right hand gets relatively close (it's actually not that close, angle makes it seem worse than it is), but look at where my other hand is! Far away holding the body firm! Two reasons why that hand is there and key:

1- Think about the direction of the bit. If it were to catch it would throw the piece TOWARDS my right hand. Hence why I feel more comfortable letting that one get slightly close, as it would be flung AWAY from the bit.

2- My left hand is the stabilizing hand, not the feeding hand. The farther away from the bit that is, the more torque I have with a firm grip to hold things steady. It's much easier to control and keep a firm hand with higher torque. Also, following rule #1, this one's the one that's nice and far away.

Respect and fear are two VERY different things.

Chris

[demonx]

It's basically the same thing I'm doing, except I have a safety handle in replace of the closest hand, I also wear safety glasses and dust extraction on the table router. I always wear them with nearly every power tool. I'm so used to wearing them at work that I don't even notice I'm wearing them in the shed and sometimes I'll lock up for the night and leave forgetting to take them off I'm so used to wearing them!

Thanks heaps for your input.

[verhoevenc]

No problem. Glad I could help.

And yes, I do realize I'm bad about eye protection (shoes in the shop too hahaha). One of these days I'll fix those.

Chris

[demonx]

I should elaborate on the safetly glasses, I'm either one of two extremes, a) wear them all the time and forget their on or have to have a pair sitting on every piece of machinery so I remember to put them on if I'm not already wearing a pair! Don't even know how many pairs are floating around my shed at the moment, probably about eight or so pairs compliments of work!

[verhoevenc]

That may have to be my new plan! The shoes should be improved soon though! As of today my shop is no longer in SC, and is now up here in MD with me. It's in the barn however, so shoes will be needed for venturing to it to start!

Chris

PS: Site fits on my screen just fine now

[Maiden69]

I'm guilty of doing this in my first guitars. I simply made a template and then placed it on the blank and with my plunge router took about 3/8" at a time until I went through the entire thickness of the blank. Now I use a long blade jigsaw, or a band saw if I can get a hold of one and just cut as close to the line of the body, and rout the last bit like Chris posted on the video. Even when I was doing the rout through I rarely got a tear out. I think only one guitar out of the top of my head that it occurred, but the piece came out entirely and I was able to glue it without showing much tear signs.

[Prostheta]

I have successfully used a small bushing to keep the bit offset from the body before a final cut with a guided bit. Can't beat a bandsaw though.

[dpm99]

Can't beat a bandsaw though.

I mean, sure, that's entirely true. But it takes some people years to get to a place where they can buy a good bandsaw. Until then, a jigsaw does the job nicely, and it's much easier to change a jigsaw blade than a bandsaw blade. I still use mine a lot.