Set Screw Machined Using A Drill

I really like my little old Ryobi Scroll Saw, model SC162VS.

Unfortunately, I lost the "Plain Blade Set Screw," Ryobi part  #1130262, A60 in the exploded service part diagram, and the red thing in the drawing here. Actually, there are two such set screws to grip the blade at the top and bottom, and I lost both. What makes that really unfortunate is that a quick search on the web reveals the part is "Obsolete -- Not Available." Ever try using a scroll saw with the blade not held tightly?  :-(

It took me several tries to come up with a replacement. What worked was using a drill as a mini lathe to modify a "Socket Head Cap Screw." This Instructable should allow you to improvise your replacement part in one try....

Step 1: Stuff You Need

What you need is a set screw to fill the hole in the picture....  More precisely, you need two of them.

We'll make our improvised replacements using two "Socket Head Cap Screw M5-.80 x 16." That answers one problem I solved by trial and error -- this is apparently the correct metric thread for this part. The head is fit by one of the wrenches that came with the saw, although not the long one with the plastic handle. It cost me about $0.80 for two of these screws at a local store.

The catch is that the thread will not let this screw in far enough to clamp the blade. I don't know why, nor do I care. It screws in far enough to be very solidly held. So, what I did was to simply remove some threads from the end of the screw so it could go in all the way. I did that using:

* A drill press (or power hand drill that you can clamp to a table) -- we'll be using this as a mini lathe
* A metal file -- the cutting tool for our lathe

Comments

[pin]

A quick tip, anytime you are cutting off a thread it is good engineering practise to put the correct size nut on first, then after you have cut the bolt or filed the thread, by unwinding the nut off it will reset the thread. Hope this helps someone someday. Nice idea for a pillar drill tho.

[ProfHankD]

You are absolutely correct. I didn't do that here because I didn't plan ahead enough to buy a nut when I bought the screws.

[scionmiami]

You guys saved me a lot of grief. The part, as you say, was listed as "obsolete".
My hardware store had the M5-.80X16 cap socket screws. For 95 cents each I am back in business using plain metal cutting blades on my Ryobi SC162VS. I also used the nut to clean the thread. It pays to check the Internet. Thanks, again.

[gephardt]

Nice, simple approach. Anytime you can modify a commodity part for a special purpose, it's great. Reminds me of how I turned one of those disposable Allen wrenches into a hex bit for my drill...with nothing more than bolt cutters.

[Phil B]

Good job. It is discouraging when you can no longer get parts for older, loved tools. Another possibility is to use a grinding stone bit and a light touch with Dremel tool (assuming you have access to a Dremel). The file is a good idea, but if I put too much pressure on it, I might knock the screw off-center in the drill chuck.

[ProfHankD]

Thanks; good to hear it may help some others.

I find my Dremel very useful for free-form grinding and cutting, but have never had much luck doing precise machining operations with it. As a kid I used a jeweler's lathe to make model parts, and that would have been perfect for this, but a couple of years ago I gave it to a friend who actually makes jewelry....

The screw in this Instructable has a socket head, so the head has a fairly long cylindrical section for the chuck to grasp. It also doesn't take much pressure on the file, although keeping the file moving helps. The screw is held very firmly in place and, with an appropriate tool rest for the file, this seems quite safe. Of course, wear safety glasses and be careful.

I would NOT chuck an ordinary screw this way. If I needed to chuck a screw with a thinner head, I'd try chucking a jig holding the screw. Perhaps using nuts would provide a suitable chucking surface for some screws? In general, I'd really have to think about how to make a jig, but it would probably involve using a screwdriver bit with some kind of trap to keep the screw attached to it.

[Phil B]

You might find this Instructable interesting. A friend has a Sawsmith radial arm saw from the 1960s. The arbor requires a blade with a hole 1 1/4 inches in diameter. The man who sharpened his original blades went out of business. Using fairly common tools, I expanded the 5/8 inch center hole in a standard 9 inch carbide tipped blade to 1 1/4 inches and kept it completely centered so it runs free of vibration, wobble, or hopping.

[ProfHankD]

Yup, a jig like that is the way to get precision using a Dremel... building things with precision usually depends on making specialized tools/jigs.

[turbobug]

I bought one of these at a flee market and got another one from co worker (a bit older its made of steel and weighs a ton. I thought that it only held saws with pins in them which sucked because you have to drill 1/4 inch holes. Ridiculously large. my older scroll saw was missing a set pin on the linkage no problem and also the foot that holds down the wood made one out of a bracket. I got them for the pinewood derby along with some hand tools for the kids. I have to check those pins

[kelseymh]

This is a great little project, and falls firmly in the category of "Awesome tricks every DIY-er needs." Thanks for the great write-up :-)

And I agree with Phil. I'd be nervous about pressing a file up against the screw in a drill chuck. Running a Dremel against it, with almost zero force, seems slightly safer to me (but then, I don't have the best lathe technique).