Thread: Slowing down this scroll saw

If you have the ability and equipment, you might prefer to make something like this

New marquetry tool/machine

It worked quite well though I haven't done much with it since making it due to there being too many other things to do

Cheers
Arron

Elegant simplicity! However, I can't see the power source in the picture. Was there just the one picture? Is it hand, or somehow, foot- operated? Drawerslide connected to a foot pedal? Do you have any more information as it does look doable, just not enough detail for me to fill in the blanks but very excited to find out more. While looking for a link I saw the dreaded amazonawes posing as a marquetry website and almost clicked on it so be warned anyone who's following this thread. (Ransomware trojan)

Arron, I look forward to more info if you could provide it or a link. Thank you, Jen

EDIT, nice inlay!

Hi Arron,I have never owned a scroll saw so I can't comment on their effectiveness for cutting marquetry.
It is possible to build quite an effective marquetry cutting fretsaw on a small budget.

The one I built as pictured probably took 2-3 days or so and is built around an old stainless steel hospital trolley and various bits and bobs.
It can accomodate large projects as it has a throat of around 60cms.It is completely hand powered,I got used to steering the work around with one hand.
The pictured marquetry piece was cut on this saw.

One thing often over looked when running a motor at reduced speed for periods of time is the reduced cooling effect from the fan. If you half the fan sped you reduce the air flow by four times. If the motor is supplied with a speed control hopefully the designer has taken this into account. If you slow it down even further you run the risk of over heating.
not sure of the design but if you could mechanically half the speed then use the electronic speed control.

Originally Posted by Cleokitty

Elegant simplicity! However, I can't see the power source in the picture. Was there just the one picture? Is it hand, or somehow, foot- operated? Drawerslide connected to a foot pedal? Do you have any more information as it does look doable, just not enough detail for me to fill in the blanks but very excited to find out more. While looking for a link I saw the dreaded amazonawes posing as a marquetry website and almost clicked on it so be warned anyone who's following this thread. (Ransomware trojan)

Arron, I look forward to more info if you could provide it or a link. Thank you, Jen

EDIT, nice inlay!

There should be plenty of information on this saw on the web, as many people have made versions of it.
This guy even sells plans for it : http://www.wood-veneers.com/j-home.htm
I'm not sure what information you need though so if you have any questions about how I built mine then just ask.

and yep, its hand or foot powered. For hand powered, just use the little cabinet handle you see in photo 1. For foot powered, I initially just attached a loop of string to the drawer slide so it nearly reached the floor. You provide the downward motion with your foot, and the spring provides the upward motion. I refined that later by adding a foot pedal.

Anyway, you can see from my post and from Mark David's that its not too difficult to make a human-powered version of the scroll saw. Just as it was made and without any fine tuning mine was more accurate and less inclined to break the stock then a scroll saw (which is not saying much really).

cheers
Arron

Also, if you haven't done so already do this search on chevalet (as used for traditional marquetry) :

chevalet marquetry - Bing images

All look a bit too complicated and time consuming to make to me, but worth looking at.

Thanks dinosaur. That's the main reason I want to get the appropriate piece of equipment to plug into. Fan speed controls etc. won't work and I don't want to damage the motor. It's designed for 400 - 1400 spm. I was hoping to ask a TAFE or QUT faculty member but they're on holidays still.

Thanks again, Arron, for the additional information. I had another look at your photo and this time spotted the spring. I had thought that was some kind of shiny bolt and couldn't make sense of it. I have also looked at the chevalets before, and agree, far too complicated, they're works of art in themselves, as is Mark David's classy suggestion. I like that his appears to be cat-powered. I have two of those so would have a spare.

I'll give your design some thought as I like the simplicity and we have everything on hand, except possible a suitably stretchy spring. Do you have a picture of the foot pedal you made? I've come up with some ideas but have a concrete floor in the shed so can't bolt it down to keep it on the floor against the recoil of the spring.

Here are some free plans, but again quite complicated. I may not do much after I finish the project I bought the saw for so don't want to invest too much more time and money than I already have. Jen

Furniture

Originally Posted by dinosour

One thing often over looked when running a motor at reduced speed for periods of time is the reduced cooling effect from the fan. If you half the fan sped you reduce the air flow by four times. If the motor is supplied with a speed control hopefully the designer has taken this into account. If you slow it down even further you run the risk of over heating.
not sure of the design but if you could mechanically half the speed then use the electronic speed control.

There is generally a fair bit more cooling leeway available for even standard motors. The power generated and temperature of the motor depends mainly on the load. Free running a 1Hp motor only draws about 0.5A (125W 1/6 HP). Only when the motor is loaded by the work will the motor draw it's full 3A or more which the motor fan will usually accomodate. On a scroll saw I can't imagine a lot of work being performed at full motor power especially on thin stock so I doubt their motors would get that hot anyway. If a VFD is used, half speed also means half power so it can't get as hot but loaded up it still out heat the cooling capacity of the motor fan. I have 9 machines on VFDS in my shed and have not had any heating problems at slow speeds. One way around the potential overheating problem is to use a motor that develops more power so it rarely runs at full power anyway. The other way is to add an independent cooling fan. On small motors even a 4" computer style fan provides a lot of cooling.

Thanks BobL. More to think about. At the volume of cutting I expect to do it shouldn't get too hot. Where did you get your VFD's? I did send an email to a supplier but probably won't hear back till after the weekend. Jen