How slow can you go....slowing down a PC 7518.

[kfitzgerald@graphicmetalsinc.com]

We need to run a large cutter (for cutting rosettes) in our PC 7518. The cutter is rated at a lower speed than the router can go. Question: how do we slow this puppy down? Can we add an external variable speed control? Or?

Regards,

Kevin Fitz-Gerald
Project Manager

Graphic Metals, Inc.
P.O. Box 31
715 East Perry Street
Bryan, OH 43506
Voice 419-636-5757
Fax 419-636-6404

kfitzgerald@graphicmetalsinc.com (mailto:kfitzgerald@graphicmetalsinc.com)

[toys]

IF you knew someone who knows how to read a scematic and isn't afraid of tinkering you could
take out the speed control provided with the router and then add an external speed control.

Or you could buy a new single speed router and add an external speed control.

[sheldon@dingwallguitars.com]

There was an article in Fine Woodworking a couple of years ago about someone who was killed trying to use a rosette cutter in a router - flying knive I assume.

If someone forgets to set the speed before firing up there could be trouble.

What about piggy-backing a 1/2" hand drill?

[papadaveinwy]

Kevin do you have a lathe? if so chuck your rosette cutter in that and make a holder for the block of wood then feed that into cutter if you dont have one get one from Grizzley.com for about 150.00 MUCH SAFER!!!!!!!!!
I HAD TO DO ABOUT 75 2 1/2" ones for my house down in Colorado while I was building it belive me you don't want to use a large cutter like that in a router. David in Wyoming P.S. when you chuck it in the lathe you use a drill chuck on the stationary end and the wood doing the spining, then with the hand crank move the cutter into the wood slowly

[gerald_d]

When you use an electrical circuit to slow down a motor then you lose torque - and a big cutter needs more torque. Sheldon's proposal is the best - get a motor (drill) where the armature turns full speed and the output is geared down to reduce speed and increase torque.

[ron_cleaver]

If I had to do a large number of rosettes, I'd make a jig and use the cutter in my drill press.

Whatever you do, don't use a router for the cutter.

[rookie432]

What about not using a rosette cutter and actually using router bits to do make the rosettes
I have had fairly good luck making rosettes using Ovolo bits(plunging roundovers) pointed roundovers and decorative plunging bits. May take a couple of passes but I end up getting a pretty smooth cut. I'm sure drill pressing the rosette cutter is faster but I've never used one so I'm not sure how well they work. However, I can load a 4" wide by 8' board and let it go.
Just a thought.

Bill

[graphicmetals]

Believe me, this is not my idea. The boss wants to load up a table full of rosette blanks and let the SB cut them unattended. We already make them on a drill press, but someone has to stand there and operate it.

I've thought pf Bill's idea, but we have stock profiles that cannot be duplicated efficiently with router bits.

-Kevin

[rgbrown@itexas.net]

I've made the rosetts with "logos" in the center, mainley College and sports logos.

Ron

[rookie432]

Kevin,

To re-create your profiles there are several manufacturers out there that will custom make cutter heads for you. There is one just 30 min north of me called Herco Tools that specialize in making cutters for the CNC. They also have a great price on diamond endmills. About $250 FOR A 1/4" straight bit. Talk about and endmill that lasts.
Their website is http://www.3d-diamond.com
I've met with them before and they state that they can manufacture any cutter you want just give them a drawing.
Another Idea

Bill

[rookie432]

P.s.
I see you are in Ohio too. This company is in New Comerstown Ohio 20 minutes south of New Philadelpia/Dover. Always good to see a supplier and another botter in the same state.

Bill

[jkforney]

Kevin
Rosette cutters are rated at between 1800 and 3000 rpm depending on the type wood used. To put them in a router would be very dangerous. If you attached a small tefc motor to the z axis that would go the rpm you want it would be a lot safer. ShopBots will work with what ever size motor you can find a way to attach. You might try Grainer for a motor that would work. There are many 1725 rpm motors. With two z axis and two cutters in routers you could, as Ron pointed out, make some nice rosettes.

John Forney

[gerald_d]

Hi John, nice to see you here again! TEFC motors are normally brushless and give years and years of no maintenance life. Unfortunately, they are also very big for a given power output. A 2 horsepower 1725 Rpm TEFC motor is a beast. Would still go along with Sheldon's 1/2" hand-drill proposal - also because it already has a chuck.

[papadaveinwy]

If your Boss is head set on this I would have him spring for a machine shop to to make up a spindel holder for the cutter then run a reducing pulley setup from the router to the cutter both with pullies kind of like running an engraving head that way you don't have to change between a router and something like a drill. the spindel holder of course would have to be attached to your z but this would work.

[graphicmetals]

Thank you all for your input, especially those regarding safety. I am going to "highly recommend" that we cut these with conventional and/or custom made router bits. Thanks again.

-Kevin

[Curt]

Kevin,
I have a 1/2" Makita drill(about 15 years old).
When I bought the drill,Makita made a small drill press for it to mount into(about 20 inches high total). I didn't have a drill press at the time, so I bought the drill press stand. I am a finish carpenter and bring it with me on the jobs, I use it for making wood plugs and also have drilled rosettes with it.

I don't know if Makita sells this drill press anymore, but the way the drill mounts into it I think it could be adapted to fit the shopbot.

The way the drill mounts into the drill press is
1) the drill slides into place
2) the drill has a perfectly round area that is 1/2" wide right behind the chuck, this slides into a collar on the drill press and the collar can be tighten with a lever to hold the drill in place.

3) the press has a small bar that that holds the drill in place. by turning the bar and pushing it tightly against the top of the drill(back of the handgrip), it can then be tightened and the drill will not push upwards when trying to easing the drill into wood for your cuts.

There must be some way to mount this on the shopbot in this manner, one thing I would be concerned with though is if the rosette is not perfectly perpendicular to the surface of the wood you wouldn't get a clean cut.

[Curt]

Kevin,
I found a picture of my Makita drill press stand on the web at www.atoolforyou.com/makita/makita_drill_access1.html

[sheldon@dingwallguitars.com]

Kevin,

I know you are rich in suggestions at this point, but here's one more. We piggy-backed an air spindle next to our router. The collets, or in your case the collet and the drill chuck would be at the same height. That way the drill can be permanently mounted and as long as there is no bit in the chuck, it will not get in the way of routing. Remove the router bit and then you can use the drill. The only thing you need to do is figure out the offsets.

I can post a photo if you like.

[jkforney]

Gerald
Always been here. Just so many right answers from people no reason to post.


John Forney

[gerald_d]

Keep an eye on us John, we make the human type of mistakes too!

[csbrads@comcast.net]

I am trying to cut rosettes on the shopbot using two different router bits. I have a dxf file but the divisions on the rosettes do not appear to be equal and I do not know how to fix it. Would someone be willing to help me fix this file?

Thanks,

Carroll Bradshaw

[bjwat@comcast.net]

Carroll,
Send me an e-mail attachment and I will give it a go.

-Brady
bjwat@comcast.net (mailto:bjwat@comcast.net)

[jkforney]

Carroll
Are you saying that the right/top is not equal to the left/bottom? If so, simply, split the design in half, delete the half you don't want and copy the balance and connect. The program you use will determine the steps necessary to effect the above.

If that isn't what you mean, perhaps a bit more information would help so we can help.

John Forney