PDA

View Full Version : Router speed control


coogrrr
Mon 01 October 2007, 15:13
Since this is the router area I use a Hitachi that has a dial speed controller. I think that the milwaukie and the hitachi are the same btw ;) Can I wire that dial speed controller in the top of the hitachi/milwaukie to the electronics of my cnc?

Thoughts?

Coog

Gerald D
Wed 03 October 2007, 09:55
Out of curiosity, could anyone sketch a typical scenario where they want the router to make speed changes while they are not near to the machine?

Bill McGuire
Wed 03 October 2007, 11:18
"...want the router to make speed changes..."
This may not help, but Harbor Freight has a variable speed router control (http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=43060)for twenty dollars. I don't know if it can be adapted for this use...
Bill McGuire

Gerald D
Wed 03 October 2007, 11:29
Folk must be aware that reducing the router's speed with the typical speed controller, leads to a very significant drop in torque. The only way to recover torque at low speed is with belt pulleys or gears. You can't leave your car in top gear and then try to drive at 10mph by using the gas pedal as the only controller. Spindles almost maintain their torques at low speeds - but they do loose HP (power)

coogrrr
Thu 04 October 2007, 06:55
using an electronic speed controller is for a couple of things. 1 is to set the speed in the gcode for the material selected and 2 is to turn on/off the router at the beginning and end of the gcode also.

It would be nice to get control completely in mach3 is all.

Coog

Greg J
Thu 04 October 2007, 09:18
One quick input, then I'm gone for a week to the mountains :D.

I still don't see a reason for speed controller speed control. Maybe your cutting one material, and then transition to another material of different density. It seems like allot of work for a little return. Just thinking out loud.

using an electronic speed controller is for a couple of things. 1 is to set the speed in the gcode for the material selected and 2 is to turn on/off the router at the beginning and end of the gcode also.

Coog

Gerald's original question - could anyone sketch a typical scenario where they want the router to make speed changes while they are not near to the machine?

Gerald D
Thu 04 October 2007, 09:42
using an electronic speed controller is for a couple of things. 1 is to set the speed in the gcode for the material selected and 2 is to turn on/off the router at the beginning and end of the gcode also.
It would be nice to get control completely in mach3 is all.

1. Yes, you need to set the speed for the MATERIAL selected. GCode does not select the material. You select the material while you are right at the table. Well then, since you are there, why not turn a knob? You could even tweak the knob for the cutter sharpness, or for the knot in the wood that the cutter is about to pass through - the gcode knows nothing about the sharpness and knots, so it can't make an informed pre-programmed choice.

2. "turn on/off the router at the beginning and end of the gcode" That is something completely different to a speed control - that is a simple relay, that function is already built in.

An automatically speed controlled router makes sense if you have an automatic tool-changer, but you havn't mentioned this so I don't think you really need to go all trouble to twiddle a pot (2 ports, driver, etc.). Bear in mind what I said before - you loose lots of torque. So you might want to go for a VFD controlled spindle . . . . . . .

Gerald D
Fri 05 October 2007, 04:00
Pot Driven by stepper Speed Control Board
(http://www.cnc4pc.com/Store/osc/product_info.php?cPath=25&products_id=149)

DMS
Fri 22 February 2008, 10:14
Copied from another thread:

Thanks Gerald,
One more question, I think I am not bothering you.
Should I go for Makita 3612 C (2300watt (3hp) Eletronic control) or Makita (60mm plunge depth, 1,850 watts (2.5hp))

http://www.makitaindia.com/beta/description.php?model=3612C&category=5
http://www.makitaindia.com/beta/description.php?model=3612BR&category=5

I am asking you because I have read in forum somewhere that Electronic control should be removed while mounting router.

Regards.

Gerald D
Fri 22 February 2008, 10:34
We use the 3612C (with the handles removed) - it starts okay with normal relay or contactor. I don't know if a Solid State Relay (SSR) will start it. It is a good, tough router.

DMS
Fri 22 February 2008, 10:43
Thanks Gerald,
If the Dial up variable speed:9000-23000rpm is usable of this router in Mechmate ?:o

Gerald D
Fri 22 February 2008, 11:22
I don't know if I understand your question. You definitely want to have variable speed. I don't see how it can work with one speed only. Cutters have a big range of diameters - small ones turn fast, big ones go slow.

DMS
Fri 22 February 2008, 18:38
Gerald.
Like spindle one can set rpm while cutting (while gantry moving) through VFD if cutting speed doesn't look satisfactory for a particular job. But since electronic contol of router is on router itself, how one can set rpm while cutting job is going on ?
rpm of router can be set before job work starts, but if it is not slow or fast enough then how to set router rpm again - (1) pause - set rpm - resume. (2) or any other method.

I don't know if it is a dumb question, I asked because right now I don't know and I don't want to regret later if I am shy away.

Regards,

Gerald D
Fri 22 February 2008, 21:03
Speed control during cutting with the router will be as you are thinking - stop the cutting, change the speed, start the cutting. Unless you can reach the control on the router with your hand (seldom easy).

For the spindle, Mach has got a facility to change the speed from the keyboard. But, if we use the parallel cable and PMDX-122, we cannot use that facility. You need diffent hardware to get the spindle speed to work from Mach3.

However, with the spindle, it is easy to reach the VFD's control while the machine is cutting.

cobra427mnsi
Fri 22 February 2008, 21:32
I have had several variable speed routers apart, over the years, to change bearings. I remember the speed control as being a separate electronic device incorporated into the router body. I wonder if it is possible to remove the speed control and install it in a remote (from the router) easily accessible position. Don't know if it is possible. Just a thought.

Paul

DMS
Sat 23 February 2008, 02:36
If speed control unit is separable than there is a possibility that this can be mounted with push buttons on gantry.

Gerald D
Sat 23 February 2008, 02:50
One can buy general purpose speed controllers for small power tools (similar to light dimmers), but there could be a huge difference in quality between different types that may result in damage to the tool.

. . . . . had to say that before the classic discussion on speed controllers starts all over again :)

Sharma, I don't know if the Makita controller can be moved easily - will you let us know? ;)

Gerald D
Sat 23 February 2008, 02:52
Paul, the Milwaukee controller uses a feedback signal from a speed sensor on the shaft. But there is a company that does a special remote speed control for the Milwaukee.

DMS
Sat 23 February 2008, 03:05
Gerald,
Right now I don't have one. When I have one I am definately experimenting with it.:)
Here is exploded view of 3612 C, part no. 3 is control unit, which can be extended upto gantry side.
Any comments ?