Scroll Saw Vibration

[Insane Dust Maker]

I know this topic has been discussed before, but none of the discussion have the strange problem I sit with.

First a little back round I have a similar saw as your Wen that has been modified beyond its wildest dreams, I made a stand out of 1/8” x 2” angle steel frame, as I can’t weld it was bolted together spring washers were used and two nuts with Red Loctite applied to lock them in place to prevent any movement. 4” from the ground a shelf was fitted again ensuring the legs can’t move out, on the shelf is two 88 pound concrete pavers adding to the security of no movement at all. 
 

Now the coin test was done and the coin fell over between  3/4 and full speed which does not concern at all as I don’t cut at those speeds, so now I add a Foredom Foot Pedal, and the strange things happens, the saw is set to full speed, but when I use the foot pedal I have vibration, take the foot pedal out no vibration, so coming from the electrical industry ( heavy current) not understand electronics I started thinking even though the saw speed control is at full speed and the foot pedal is now controlling the speed is there no some form of conflict between the speed control devices. Removing the foot pedal and setting the saw speed to my preferred cutting speed which is between half and three quarter speed mo vibration at all.

So is thre anybody in the community that can throw some light as to what the problem could be.

[JTTHECLOCKMAN]

Never, Never, Never use a VS speed control footpedal with a scrollsaw that is VS speed control. You will burn the board out or possibly the motor.  Speed controller can not control a speed controller. Get a on/ off foot switch and set speed by way of scrollsaw.  I have always used the momentary ones where you need to stay on it to keep saw running. There are ones that is push to start and push to stop. But I found that just taking your foot off the footswich is faster than trying to panic and step on it again to stop for fear of stepping on it more than once and you now start it again. Especially when the blade breaks and the blade will break.

Edited March 17 by JTTHECLOCKMAN

[Insane Dust Maker]

That was my thinking, I don’t know if I can get a on off foot pedal here in South Africa, maybe I can modify mine to do that will have to open it to see if it’s possible. 
Thanks for this advice.

[Insane Dust Maker]

Okay so I have checked with the local electrical wholesalers and they do have a “Push to make Lift to break” foot pedal which will be ideal, it is sold as a light duty foot pedal maximum load 16A which is an over kill but I’m sure this will work fine.

Thank for your advice and assistance.

[NC Scroller]

On 3/18/2024 at 2:50 AM, Insane Dust Maker said:

Okay so I have checked with the local electrical wholesalers and they do have a “Push to make Lift to break” foot pedal which will be ideal, it is sold as a light duty foot pedal maximum load 16A which is an over kill but I’m sure this will work fine.

Thank for your advice and assistance.

What is most often used is a "deadman switch" foot pedal.  You push down and it runs.  You take your foot off it stops.

Like this one:

Coolneon Foot Switch Normally Off Press and Hold to ON 10FT UL Cable & Plug, Dead Man Pedal Momentary 15A 250VAC US 3-Prong Piggyback for Lichtenberg Machine Table Saw Scroll Saw Miter Power Tools | WantItAll

[JJB]

I agree. Deadman switch is the way to go if you are looking for a foot pedal. Personally my muscle memory is geared toward controlling the saw via the stock controls. I'm afraid I might mess up my rhythm with a foot pedal.