(Dunlap) Scroll Saw Repair
I purchased this scroll saw at the same time that I got my joiner.
Much like my jointer, it was in need of some love. So in this instructable, I will show you how I went about getting this back in working order.
Supplies
Various drivers for nuts, screws, bolts, etc.
RAGS
Working mat
Something to clean oily residue (I used turpenoid)
Something to treat rust (I used household vinegar)
Something to neutralize rust (I used baking soda)
Something to clean rust (I used sand in a bottle), or a grinding wheel/brush
New cord, as needed
Machine Oil, as needed for motor wicks
Motor oil for reservoir, as needed
New blade(s)
Video of My Process and First Cut
Check out my video of the process and my first cut with the repaired saw!
Also, If you haven’t already checked out my instructable for how I restored that and sharpened blades, please take a look!
Breaking It Down
Most of the moving parts were slightly seized based on years of being stuck in a barn (this is literally where the guy got it from when I purchased it from him. That and the joiner…)
Another big hurdle was the fact that it didn’t have a motor and a workable blade.
A free manual that I found online said the saw calls for a 3/16-inch wide x 6-inch long 15 tooth per inch (TPI) blade and a 1750 rpm motor. Unfortunately, the standard size for scroll saw blades has changed since this was manufactured. Nothing a pair of snips couldn’t handle for what it’s worth. I also purchased a second scroll saw from an online marketplace in order to get a new motor and pulley. The price was right considering a new motor costs many times more what I paid for this second scroll saw. . .
I personally like to document when I take things apart because I will usually forget what piece goes where. The pictures above were taken from said videos and they did the job well!
I started by simply taking everything apart. I took the scroll saw blade rest, the spring, the bed, the bottom blade holder and the crank case apart (I'm sure the nomenclature of what I just described might not be exactly correct but hey, I am no expert).
Clean It Up
Now that the pieces/parts are off of the machine, I gave the body a thorough wipe down to remove any dirt, grime, wood resin, and oil.
I used turpenoid (if you ever watched Bob Ross, you may be familiar with this product. But mineral spirits would also work) to remove any grime from the metal pieces that I removed. This was followed by rust removal and in order to accomplish that I just soaked them in white vinegar for about four hours. The vinegar solution was neutralized with baking soda to stop any acidic attack on the bare metal. You could also just use a grinding wheel or an abrasive brush to remove any superficial rust. After most of the rust was removed, I put the metal fasteners and parts in a bottle filled with dry sand and shook it. This was my “sandblaster“ but you could just use a real sandblaster if you have one available. Even an abrasive pad would work, I’m sure.
Oil It Up
The crank case was filled with oil according to the manual. Mine, specifically, called for SAE 30 in the reservoir and SAE 20 for the pulley bearing.
Motor It Up
Pictured above is the motor that I procured from the second scroll saw. I would have loved to have started a true restoration for that one since it is older and it looks cooler (in my opinion) with the hexagonal bed, however, I came to find out later by testing that that one was coated with lead paint so I immediately stopped.
The motor actually fired up just fine with the electrical connections that I bought it with, but I was not comfortable with the amount of fraying in the old cord. The new cord is grounded and follows the same color scheme as most modern chords do in the United States. There were two pots on both ends of the shaft that I had no idea what they were for. It wasn’t until I was researching old desk fans (which, by the way, I have another instructable for, too!) when I found out that they were oil pots. The only problem with that was that the wick inside was dry and crusty. Yuck! So I promptly ordered new ones, filled them with machine oil, and reinstalled them. Now it fires up just fine. I am actually very happy with finding this old timey motor because I feel like with a little TLC it will last a loooooong time.
Build It Up
Finally, I built a stand out of some spare 2X3s. I made a base for the motor to sit on and, of course, the scroll saw itself is on top. This stand has some vibration since it is made out of wood, but I could just put in a brace and some added weight at the bottom and it would help. For my initial purposes, this will do and get the job done.
I am constantly needing a wrench to maneuver the blade so I added a magnet to the front to keep that and a metal bar handy.
Changing out the blade on one of these is quite easy. All I do is completely remove it from the top and loosen the bottom holder so that I can move it forward on the bed. I then insert the piece of wood and reverse the process. That being said, I ran into some problems with the original fasteners. They were nicked & needed to be filed/sanded smooth on both ends. Just five minutes worth of work helped tremendously to keep the blade secured while it oscillates with the motor.
Cut It Up
Once everything was ready to go I decided to reproduce a laser cut Texas that I made at Techshop years ago. And really, isn’t that what a scroll saw is all about? It’s basically just a “low tech” laser cutter. Hopefully I didn't anger any scroll saw enthusiasts...Either way, I think that it turned out very well for my scroll saw debut.
What do you think? How did my first cut go?
Thanks for checking this out and I hope it helps with a restoration you may have or get you interested in a scroll saw in general! Honestly, in my area, people are basically giving these things away, especially older models. Go grab one and give it a go. If you don't like it, you may be only be out a few bucks.