View Full Version : cutting circles

02-04-2008, 12:02 AM
is it ok to make a full cut right through the mdf right away with a router or make small cuts at a time?

02-04-2008, 12:04 AM
i use a jigsaw, just steady. I do make more than one cut though

02-04-2008, 12:13 AM
i mean go all the way around but do you want to take out like 1/4" at a time or is it alright to do the full 3/4" right away

02-04-2008, 12:14 AM
Do multiple passes.

Doing it all at once is a good way to toast bits.

02-04-2008, 12:15 AM

02-04-2008, 12:15 AM
I usually do 3/4 MDF in either 2 or 3 passes...normally 3.

02-04-2008, 01:42 AM
I'll say 3 passes for 3/4" MDF. I've snapped bits trying to do it in 2.

02-04-2008, 10:32 AM
1/4" at a time is how I do it as MDF is pretty hard on bits...

02-04-2008, 11:04 AM
Awww.... the joys of using Trupan. 2 passes works well for me. But, seriously, the more passes the better. Not only is it bad on your bits, but its bad on your router as well.

02-04-2008, 11:12 AM
Can you guys explain passes? I have a feeling I've been cutting my holes incorrectly. *shoots himself in the face*

Wait, I think there is more than one thing here. If talking about a router, that is what I do too. But if talking about a jigsaw, are there passes?

02-04-2008, 11:14 AM
Using your plunge router, you simply lower it a little more every pass, until you've gone through the material...

02-04-2008, 03:31 PM
Yea, you cant make passes with a jig saw. I think most of the people here were talking about using a router.

02-04-2008, 03:40 PM
yea i was refferring to a router

02-04-2008, 03:42 PM
Roto Zip with home made circle Jig FTW!

02-04-2008, 09:16 PM
i usually go 4 passes with a 1/4'' spiral bit seems to not make the router scream so much.And im hoping for a little longer life out of the bit

02-04-2008, 09:24 PM
I use nails and a really big hammer.

02-04-2008, 09:37 PM
I use nails and a really big hammer.

I just give the piece a mean look and it cuts a hole in itself in fear. :cool:

That or i call up Chuck Norris and he'll give it a hefty roundhouse kick if the box is a little too stubborn.

02-04-2008, 09:37 PM
roto zip has a circle cutter attachment that goes up to 12 inches. that's what i used to cut my holes.

02-04-2008, 10:52 PM
That or i call up Chuck Norris and he'll give it a hefty roundhouse kick if the box is a little too stubborn.

I thought this was the preferred method :fyi: lol

02-05-2008, 01:05 PM
I use a Rotozip and a wooden yard stick and I take all 3/4 in one pass. Starting from two inches on the yard stick where I have a hole that I use as a center; I just drill a small hole the length of the radius I need to cut. Then i stick a pen in the hole and rotate it around to make a perfect circle.

I'm pretty dam good with the Rotozip. I touch the line (but not take it) all the way around and only vary about 1mm. The bits eventually break but Lowes has a warranty on them so when they do I just take them back and get new ones.

02-05-2008, 04:35 PM
I usually just use an upcut spiral bit and just do 1 pass... it has worked well so far and nothing has been broken, still sharp too.. i might just try doing a few passes next time but my question is...

if you do 2 or 3 passes doesnt it makes the tip of the bit really dull as that is the only part touching the wood as apposed to the whole bit doing work?

02-06-2008, 12:02 PM
does anyone use double sided tape or anything to hold the piece down, cuz i would think that once your almost done the center piece will start moving

02-06-2008, 12:23 PM
If you have problems with the center piece moving you could just save the last inch for a jig saw. But a steady hand and patients towards the end should could work too.