Mini Block Plane Build Plans

This is a very detailed guide, along with demonstration videos that show you how to make this small wooden horn block plane.

I first restored a vintage version here and then made a prototype, then designed an even better version with a unique sliding dovetail body and made 3 of them, so this guide is definitely not half baked.

Download the Sketchup Plans (3D Model)

I am more than happy to answer all questions on YouTube in the video comments.

Video Part 1

Make the Sliding Dovetail Plane Body

You need 2 pieces of hardwood approximately 150 mm long. (for one plane body)

Exact dimensions are in the plans, note you need to start with a longer pieces so you can square the ends.

I used a length of merbau fence railing because it is cheap and incredibly hard and durable.

Due to the majority of operations being machined, it is safer if the length is longer and I suggest at least 300 mm so you can make two at once.

I thought I could stuff one up so used 450mm and made three planes in one go.

The plans assume you have a 4mm thick saw blade and you must ensure the saw blade is accurately set to 90degrees before starting

Cut the right hand side first

This is the pin side. (The male part of the dovetail)

Looking from the front, the right hand side needs to be machined

• 28mm wide or a bit more if you want a deeper dovetail.
• 60-70mm high (allowing for supportive material to be left behind for future steps)

The “exact” position and size of the dovetail is not critical as the block can be trimmed to final position it. 

From the front it looks best if positioned in the center of the nose but make sure it is no less than 10mm from the bottom so that it looks good inside the mouth.

With a dovetail bit in a router, cut up to the bottom of the pin

Then using the dovetail bit, same depth, cut the top of the pin and hog out the material above it.

This part with the pin should still have the excess material at the top left over to use as support.

Cut the left hand side next

This is the tail side. (The female part of the dovetail)

Looking from the front, the left hand side needs to be machined

• 23mm wide (allowing .5mm for sanding and clean-up)
• At least 50mm high (allowing for cut to size)

Position the dovetail tail in a spot that allows the top and bottom of the left hand plane body to be trimmed to match the pin side.

This joint needs to be tight so take several passes with the router and creep up on the final cut.

The two halves should push together and bind a bit. If it is a little loose, the gaps can be hidden with glue but if it freely slides or wobbles, then you will need to consider cutting another one. 

Cut out the internals

Cut the internal dimensions of the plane.

Set the saw blade to cut 16.5mm into the work piece for the left hand side and for the right hand side 16.5mm + the thickness of the dovetail. The right hand side will need support under the piece because of the protruding dovetail. If this is not possible to safely cut then consider making these cuts before cutting the dovetail.

Refer to the plans and measure 62mm from the front of the plane and make a 64degree cut, use a guide jig or mitre gauge. (Remember, we will trim both ends of the plane so scribe a reference line in a bit and measure from that, you can see these lines in the first video @ 3:18)

Then make a 90degree cut 60mm from the front of the plane.

This forms a little wall at the front of the mouth. It should be about 6 – 10mm high and can be filed back later if the mouth needs to be widened.

Then make a 45degree cut for the iron’s bed.

Line up the saw blade so that it cuts as close to the front of the mouth as possible without actually touching.

This makes about a 7mm wide mouth.

Then transfer the cut marks to the other side of the plane and repeat.

Note from this point onward, the bed is the reference surface and everything else needs to be fine adjusted around it as necessary.

As per the video, scribe a line on the top of the plane to ensure the next step produces a clean and square result. @ 3:34

Chisel out the waste between the saw cuts using the scribe line as a reference to keep the opening straight and square.

—–

Make the hollowed out wooden dowel

You could use just the brass pin but it has less surface area to lock in the wedge.

Also the wooden roller adds to the aesthetic appeal of the tool. The roller rotates to ensure a flat surface presses against the wedge and makes it more solid.

Cut the blank to oversized dimensions and drill a 6mm hole through middle.

Using the hole as a center, reduce to 12mm diameter in the lathe.

Flatten one side down to about 2mm thickness from the hole.

Cut to length (a bit over size is safer at this point) I filed mine down to exactly fit the plane it was made for. Be careful to file into it so as to not splinter it. You could also use a sander.

—–

Finish the Body

Label the plane halves (to keep them a matching left and right pair) and rough cut them off.

You should now have 2 or 3 plane body blanks.

If all goes well, the internal cuts on both sides exactly match, but if not the important thing is that the 45 degree cut (the bed for iron) is lined up and the alignment of the front cuts can be finessed later with a chisel.

Chisel out the internal waste and sand etc., careful not to damage or alter the 45 degree surface as this has to be perfectly flat for the iron. 

Line up the bed surface halves perfectly flush (use touch not eye)

Glue both sides together, if your wood is oily and dense, then first clean with spirits. A good choice of glues is be epoxy as it fills gaps

The sliding dovetail joint should be a tight fit, if not it will need to be clamped during glue up

Mark out the hole for the wedge pin and drill it all the way through.

Because the insides have been chiselled out, the drill could blow out the internal wall so pack out the centre opening with scrap wood.

Use a drill press to ensure the hole is drilled parallel.

Check the flattened and hollowed out dowel fits perfectly snug and can rotate.

Glue in the brass rod securing the dowel. The dowel should end up tight but rotate freely.

Be careful not to get any glue on parts that will bind the roller.

After glue is cured, you can:-

1. Sand down the brass pins
2. Clean up the front wall in case the halves are off centre (make sure it looks parallel)
3. Trim off the front and rear ends of the body to make the plane body 140mm long
4. Cut the 15mm square front ledge

—–

Make the front horn

The front horn is a dovetail fit and only looks complicated

The trick is to first cut the blank to size using the template.

This template can be printed out to scale using SketchUp or use the measurements.

Mark out the side profile and chisel away the wood to reveal the pin.

The important thing is to keep the parts that contact the plane square. The pin itself can be any wedge shape and at this point it is not critical because the tail part of the dovetail needs to be finessed to match this.  

Draw a 12mm circle on the top, where the horn peaks.

File and rasp away the waste, blending the curves to the top circle.

Sand smooth

—–

Video Part 2

—–

Fitting the front horn.

Place the horn on the centre of the top ledge and press down.

Scribe the outline with a marking knife

Cut down and hollow out a recess for dovetail

Sneak up on the joint focusing on the top where it inserts. Then when it is a tight fit, clean the hole all the way to the bottom keeping the walls parallel.

The internal corners of the parts can be paired away so they sits snug together.

Check it sits flush and square and lock it in place with glue.

I demonstrate this clearly in the video.

—–

Make the blade (Iron)

I used 3mm (O1 tool steel) which is readily available from places like RS components.  The o in O1 stands for Oil, meaning this steel is to be quenched in oil as part of the hardening process. O1 tool steel is reasonably priced so in the end each blade only cost about $10 and it is super easy to work, and you pretty much are guaranteed a good result.

The width of the plane interior is 33mm so cut the iron width just under that, (~32mm)

Cut the blade length and square it up.

Round off top corners to taste.

Grind a 25degree bevel

Harden

Temper

Sharpen

Done

All these steps are shown in the video.

—–

Make the wedge

Assuming the plane is made to exact dimensions, follow the dimensions in the plan.

However the dimension will need fine tuning to ensure the blade is firmly held, so essentially the wedge is custom made to fit *this* plane.

Cut the wedge to thickness (so it just cant fit under the roller) then add the taper that the roller pin rides against.

The important thing is to sneak up on the fit (I demonstrate this in the video)

Ensure the top face of the wedge sits flat on the roller (I used a feeler gauge to monitor this as I made it)

I added a rounded over block on the top of the wedge which is visually pleasing and gives a bigger target for the hammer.

Make the point of the wedge sharp because we don’t have a chip breaker but also make this angle not too acute and fragile. 

When the wedge is final size, this tip should be about 1cm from the tip of the iron

—–

Add chamfers and round over details.

Round over the rear of the plane body so it sits nice on the hand.

Round over the top sides of the plane to the same degree.

Add 45degree chamfer on the four corners,

In the video I used a file with two pieces of wood as a file guide.

Give your plane a final sand.

—–

Assemble, finish, and sharpen

Apply your favourite finish, I recommend a traditional finish –

• Boiled linseed oil and completely wipe off excess
• Wait a day and then shellac.
• Then finally some wax.

Ensure the blade is honed razor sharp.

I showed the steps how I sharpened my blade but my main tip is to first get the back of the blade polished first as this is the actual cutting edge.

And second tip, even though the O1 tool steel was milled from the factory, the back still needs smoothing and it is easier to smooth before the hardening step. 

I used a 25 degree bevel then a 30 degree micro bevel on the very edge tip during final sharpening.    But use your favorite sharpening technique and blade geometry or feel free to do some further research because this is a topic that everyone has a better method but essentially it comes down to what hardware you have to do the sharpening.

—–

Tune test

The iron is placed bevel down

The video demonstrates how to bang the back to release the iron and make a lighter cut and to tap the iron to make a deeper cut.

The wedge should be firm but not too tight.

Chips should not jam in the mouth or on the wedge

If the mouth needs to be widened, take into consideration that the smallest gap is best and you can’t make it smaller later. Also if you need to flatten the sole, then this widens the mouth over time.

The end of the wedge should be about 1 cm from the iron tip, if you notice it is jamming in this area then sand it back a bit.

Add a drop of machine oil on the blade to prevent corrosion.

—–

Finally

Share pictures of your creation, you can find and tag me using the social media icons at the bottom of the page and I will enthusiastically check it out and congratulate you.

I wish you well,

Matt Painter