90° Magnetic Hand Saw Guide

UPDATE: After using this for a couple days, I've decided that gluing a thin piece of clear plastic or wood veneer over the magnets, and shaving a small relief at the bottom of the reference fence is something I will be adding to this project. It holds the saw set away from the fence just enough so it doesn't hit when you use the saw. This will save your saw set from potentially scraping the magnets which could dull or even break teeth. I am going to add this step to the I'ble as soon as I can get to it and take some pictures.

Most of my carpentry skills were learned on a construction site in my 20's. Chisels were used as scrapers and to open paint cans. And hand saws, well they sat at the bottom of my tool box untouched.

As I grow older and work more in my own shop, I'm starting to appreciate hand tools and their advantages. Some of those techniques now spill over into my rough carpentry and add quite a bit of value. Hand tool work is extremely rewarding, addicting even.

That's why I decided to make this project. I wanted a way that I could easily set up a small piece and cut it square. I didn't want to do much layout or fiddle around with anything else. I just wanted to be able to consistently cut a square edge on smaller pieces without any thought or time wasted. And that's where this 90° Magnetic Hand Saw Guide comes into play. Since I made it, I use it all the time. So let's build this thing.

Step 1: A 3D Model, the Tools, and the Materials.

Above is a 3D model I drew of the magnetic saw guide. It should give you an idea of all of the dimensions of the guide, and all the parts and pieces you need to make it.

Here are the tools that I used for this project:

Tools (In order of appearance)

• Utility Knife (Marking Knife)
• Combination Square
• Dozuki Dovetail Saw
• Gyokucho Hardwood Razor Saw
• Block Plane
• Drill Press
• 1/2" Drill Bit
• F-style Clamp
• Cordless Drill
• Impact Driver
• Engineers Square

And these are the materials I used:

Materials

• Scrap Wood (I used Cherry and Mahogany.)
• CA Glue & Activator
• 1/2" Diameter x 1/8" Deep Disc Magnets
• 1-1/4" Screws

You don't need all of these tools, and you can use any scrap wood you can get your hands on. So now let's get to the fun stuff.

Step 2: Layout the Saw Reference Fence.

I marked out the front and back of the saw fence with a utility knife. I don't have a proper marking knife, but this one works very well because I can snap off a dull edge and have a razor sharp knife whenever I need it. This piece of Cherry was cut to 5" long, 1-1/2" wide, and 3/4" thick. This will become the piece that the saw references while you make your cut.

Step 3: Cut the Saw Reference Fence.

Then I set the piece in my miter box, and cut it to the final 5" length. I've been using this miter box for a while and it works well, but if you're not paying attention you can easily cut your workpiece out of square.

Step 4: Layout and Rip the Workpiece Reference Fence.

Then I marked out with a pencil and ripped a piece of Mahogany that will make up the fence that references the workpiece. This piece, after I planed it smooth, came out to 6" long, 3/4" wide, and 3/8" deep. So make your cut a little bigger than that so you can work it down to finished size. I decided to use the Mahogany because it looked really good with the darker figure in the Cherry.

Step 5: Plane Everything Smooth, Square, and to Size.

Then using a block plane, that I picked up at a flea market for $3. And the Moxon Vise I built here, I planed all the sides of both fences. Making sure that everything was straight, square and smooth. If you don't get the pieces perfectly square and straight, it'll show in your finish cut when the guide is done.

Step 6: Lay Out and Drill the Holes for the Magnets.

Then I laid out the holes for the magnets. You can see the spacing in the 3D model above. I used a 1/2" drill bit to make these holes as deep as the magnets are thick. I would have preferred to use a Forstner bit, but I couldn't find my 1/2" Forstner bit.

The magnets were 0.47" wide, so there was a small gap surrounding them because the hole was exactly 1/2". It didn't make a difference, and the magnets were held in the guide really well with the CA glue.

Step 7: Drop Some CA Glue Into the Holes.

Then I put a dab of CA glue into the holes. I wanted enough so that when the magnets were placed into the holes, a little bit of glue surrounded the magnets in the small gaps. In my mind, this would add to the strength of the glue holding the magnets in the pockets.

This glue is a two-part "super glue". Once the glue is sprayed with the activator, it sets almost immediately and cures in 5 minutes. I love this stuff, it really is my secret shop weapon.

Step 8: Place the Magnets, Wipe the Excess and Spray the Activator.

Then I dropped the magnets into the pockets with the CA glue. I used (5) 1/2" x 1/8" thick disc magnets. They are very powerful and hold the saw securely to the fence.

Then I wiped the excess glue off and sprayed the activator. Once this glue is hit with the activator, it sets up almost instantly and is cured in 5 minutes. I let the glue and magnets set up for 10 or 15 minutes before I got them close to anything they would attract to because I wanted to make sure they were in there solid. I was really happy with how well the magnets were secured into the fence.

Step 9: Attach the Two Reference Fences.

This was the hardest part of building this magnetic saw guide, getting the two fences perfectly square.

I clamped them together and predrilled for the first screw. I checked for square again and drove in an 1-1/4" screw.

Step 10: Drive in the Second Screw.

Then I moved the clamp over the screw I just drove in, adjusted it square again, and predrilled the second hole. At that point, I could drive in the second screw to hold the saw guide square.

After this was done, I put a little bit of wax to protect it from fingerprints. You don't need to do that, though.

And then it was ready to use!

Step 11: Test Out Your Magnetic Saw Guide!

Then it was time to test the saw guide out. I threw a scrap piece on the workbench. Slid the guide up to it, and referenced on side. Placed the saw up to the magnetic side, and cut my workpiece.

I was really happy with how it worked, and it cut square the first try!

Step 12: Check for Square.

This isn't the best angle. But as you can see, the workpiece was cut square both ways.

And that's it, you're done with the magnetic saw guide. I'm really happy with how this turned out. It's going to add quite a bit of value in my workshop. I'll be able to quickly cut small pieces square without much layout or trouble. It does exactly what I want it to do, and you're sure to see it in some of my future projects.

Thanks for checking this out, let me know if you have any questions!

I'll see you on the next one,

— Adam

Comments

[Suthrngntlmn]

Adam, this looks like something I can use. I will definitely build myself one. Thanks for the information.

[Metcalf32]

What brand of CA glue is it that you used

[Yonatan24]

Fastcap CA glue, I think: http://www.fastcap.com/estore/pc/2P-10-Adhesive-c4...

[zposner]

Maybe cover the magnets and wood with a thin layer of some self lubricating plastic to reduce friction.

[Jobar007]

Use Teflon Tape instead of a wood veneer. It won't look as good, but it will last a long time.

[CHRIS11556]

To me it would be better if there were two magnets one at each end for less friction and a gap at the bottom of the face to allow for the teeth not to rub against the face. But I don't know if it would seem better to anyone else.

[CarlinC1]

That's a great tool, thanks for sharing the process!

[ElZorro]

I have been a carpenter for 40 years.
Proper sawing motion is at an angle with aggressive forward stroking with a rocking motion. Never is the saw blade flat with the stock. I only see the magnets as an impediment to proper stroking. As any one I grew up with would say, just learn to use a saw.
But nice looking work though.

[jwilliamsen]

For your slider surface/magnet shield, you might want to consider UHMW
or Delrin sheet - they're self-lubricating and tend to resist getting
gummy with friction. You'd have to double-face tape it on since I'm not
aware of glue that would work. Check with your local sign shop to see
if they might have some in their scrap bin - you might get lucky and get
what you need for free.

[Adam Gabbert]

That's an awesome idea. I actually have some UHMW off cuts from a project I did at a food processing plant last year, I'm going rip down a thin veneer use that. Thanks!

[Drake88]

You could make the magnets part of how the shield is held to the square. Just drill the holes through the shield and use flat headed screws that have the same head-size as the magnet holes. Then just allow two of the magnets to 'sit' on the screw heads.

[BarryS32]

Pretty simple Well Done ! Capt Barry47

[jimvandamme]

I have a lot of magnets from old hard drives. This would be great...

[GrahamJ12]

grajef

Brilliant instructable my next project I think.

[Adam Gabbert]

Nice.

Upload a picture if you get a chance. I'd love to see it.

[salwinks]

way to go. Good Idea. Will definetly try this!!

Sal Anderson

[DennisO22]

Now. That is a great idea.

[Lorddrake]

From the information in the video you stated that the magnets are flush with the surface of the guide. have you noticed any marring of the saw blade from contact with the magnets as it slides back and forth across them?

would it be better to recess the magnets a very small fraction of an inch a(maybe 1/64th) to prevent them contacting the saw blade but still holding it securely?

[TonkaHands]

Very cool project. Thanks for this. Doing joinery with the Japanese saws I always have trouble stopping at a consistent depth. This jig helps because it tends to hold the saw straight. I added a wooden spacer on top so that the spine on the back of the saw would come in contact with it at the proper depth. I worked very well.

[RonA24]

Great idea which I will put to use in similar projects thanks