I’ve taught this bowl-turning undertaking to greater than 500 starting woodturners over a twenty-12 months interval, and I’m proud to say my college students have had glorious success with it. If you’ve by no means turned a bowl, this undertaking is an effective one to begin with; you’ll form the bowl utilizing solely scrapers, and no chuck is required—only a faceplate, which comes with most lathes. It’s true that scrapers are likely to trigger extra tearout than a gouge, however in case you are simply getting began, the scraper could be much less intimidating and less complicated to make use of.

Choose the Wood

Preview of tiered cuts in bowl turning blank

Since the shaping of this bowl is completed with scrapers, select a hardwood, comparable to maple, walnut, cherry, or oak, that has been dried to a moisture content material of 14% or much less. Scrapers don’t reduce wooden successfully in inexperienced or partially dried wooden. They additionally are likely to tear out the endgrain of sentimental woods comparable to cedar.

Start with a spherical clean about 10″ (25cm) in diameter and a couple of-1/4″ (6cm) thick. This is an effective measurement for a purposeful bowl.

Attach Faceplate

Always examine your clean earlier than mounting a faceplate to it. Consider the grain, defects, and determine. Try to think about the form of your accomplished bowl and the way it might finest match within the cleanest elements of the clean. Consider you can flip away minor defects throughout the shaping course of, so long as they don’t impede on the realm that can develop into the completed bowl.

I exploit a 6″- (15cm-) diameter faceplate to mount the work to the lathe. Mount the faceplate to the facet that would be the high of the bowl, as you’ll flip the underside/foot first. Find the middle of your clean, and use that middle to position a compass level and draw a circle barely bigger than the diameter of your faceplate. This helps to middle the faceplate.

Mounting lathe faceplate on bowl blank
A faceplate is screwed to the bowl clean.

While holding the faceplate in place, drill a 1/8″- (3mm-) diameter gap about 1″ (25mm) deep in one of many faceplate’s outer holes. I exploit a self-centering bit, which ensures the holes are positioned correctly. Four 1″-long screws will safely maintain this clean throughout turning. It is ok to initially drive the screws with a drill, however all the time end by hand-tightening every screw with a screwdriver and double-checking that there isn’t any motion within the faceplate earlier than mounting it on the lathe.

Sharpening a Scraper

Edge Up or Down?

Classic scraper sharpening method
The typical methodology is to current the scraper innovative up.

Most turners sharpen their scrapers with the innovative up—so the grinding wheel strikes the highest of the instrument first. I favor the alternative method, with the innovative down. In this orientation, the course of the grinding wheel naturally produces a burr on the underside of the grind, which on this case is the innovative. It is that this burr that produces the reduce on the wooden, so there isn’t any have to hone a scraper. Try presenting the instrument to the grinder each methods, and see what burr you favor.

Sharpening a scraper with the edge downwards
The writer takes the alternative method and prefers the burr produced on this method.

A standard scraper has one bevel. Adjust the grinder’s toolrest angle to supply your required bevel angle (usually 70 to 85 levels). For a sq.-finish scraper, gently press the bevel into the wheel, then glide it throughout the remainder utilizing mild strain from the again to take care of contact.

Adjusting scraper on sharpening stone
The roundnose scraper should be swung 180 levels in a fluid movement.

For a roundnose scraper, you have to to face again out of your grinder far sufficient to move the instrument deal with in entrance of you. With the grinder off, apply swiveling the instrument 180 levels with out pausing.

Using finger to press blade edge on grinder
Press the instrument flat on the toolrest utilizing your finger.

The key strain level is the tip of the index finger, which helps maintain the instrument flat on the remainder. Then strive it with the grinder on, conserving the instrument in touch with the wheel always.

The Story of the Sparks

Sharpening side and corner of scraper blade

How have you learnt when you’re accomplished sharpening? The sparks inform a helpful story. If the highest of your instrument bevel shouldn’t be touching the wheel, the sparks will go down, below the instrument. Use this as in indicator: when the sparks start to come back excessive fringe of the scraper, you’ll know you make contact with your complete bevel, high to backside. Inspect your instrument after every move. When you’ve achieved a single side on the bevel, from backside to innovative, you might be able to get again to the lathe.

Rough It Round

During preliminary roughing, I set the lathe velocity to about 500 rpm. If your lathe has a pulley-and-belt system, quite than digital velocity management, use the slowest setting doable to begin. A small quantity of lathe motion, or vibration, is regular when the clean shouldn’t be but trued up. Nonetheless, by no means stand within the direct line of the mounted clean; stand on the foot or head of the lathe when turning it on, and have your hand on the cease button, simply in case the vibrations are too nice. Having a properly-rounded clean and a centered faceplate will assist scale back preliminary vibration.

Using scraper to true bowl blank edge
The work is mounted on the lathe, and the periphery trued utilizing a roundnose scraper.

Set the toolrest barely beneath the middle of the wooden, and use the tip of a bullnose, or roundnose, scraper to make tiny cuts alongside the clean’s periphery till you might be chopping wooden constantly with no intermittent gaps. Stop the lathe every so often and examine that the instrument marks made by the scraper cowl your complete width of the sting’s circumference.

Now convey the toolrest to the underside of the bowl, at a top that places the tip of the scraper on the middle of the clean, with the again of the instrument barely elevated. Starting from the middle and chopping outward to the left, make mild passes alongside the underside face. Cut a bit of deeper with every move, till you might be chopping all wooden with no intermittent gaps. Now the clean ought to run true, so you possibly can improve the lathe velocity to 1000 to 1200 rpm. This greater velocity will produce a a lot cleaner reduce. If your lathe vibrates too aggressively on the greater velocity, nevertheless, scale back the velocity to a protected stage earlier than continuing.

Form a Rough Foot

Marking bowl foot on center of blank
After truing up the face of the clean, the writer marks strains to alleviate the foot.

Mark the skin fringe of the foot by measuring out from the middle. My rule of thumb for a purposeful bowl is to make the foot barely smaller than half the diameter of the bowl. So for this 10″ bowl, I marked a 4-3/4″ (12cm-) diameter foot. Then add one other line 1/4″ (6mm) exterior the foot mark. This second line will develop into helpful later, when shaping a clean transition to the foot.

Marking edge of blank to cut down foot

Next, draw a line on the outer fringe of the bowl, 1/4″ from the underside floor. Using half the blade of a sq.-finish scraper, or a few 1/4″ of the blade, make a sluggish mild plunge reduce into the underside floor, as much as the 1/4″ depth.

Starting cut for making bowl foot
Use a sq.-finish scraper to make plunge cuts as much as the pencil strains.

Continue making cuts like this, working towards the middle, till you might be simply shy of the mark for the foot. Try to maintain your cuts constant and flat.

Cutting foot down to pencil lines

A plunge reduce with a sq.-finish scraper ought to start slowly, with mild however constant strain from the precise hand. Just because the reduce nears the underside, sluggish your feed fee and end simply because the unused a part of the blade touches the wooden.

Rough within the Rim

Marking side of bowl blank to create bowl's rim
Draw pencil strains to alleviate the bowl’s rim.

Bring the toolrest again round to the outer fringe of the bowl. Always attempt to set the toolrest so you aren’t working at its ends; making use of the instrument as near the middle of the toolrest is finest, as that’s the place you’ll have most help.

Measuring width of bowl rim before marking

Mark a line on the periphery 1/2″ down from the highest floor. Then draw a line on the underside floor 7⁄16″ (11mm) from the periphery.

Using scraper to cut down bowl rim
Use a sq.-finish scraper, approaching from the periphery.

Starting on the backside, use a sq.-finish scraper to make a collection of plunge cuts into the periphery, 1/4″ deep. Work your means towards the rim, till you might be simply shy of the 1/2″ line.

Measuring out rim area on bowl blank
Remove wooden from inside the pencil strains.

Wood is way more immune to chopping or scraping on this orientation, and you’ll discover this in your plunge cuts. Take a lesser reduce, don’t push as onerous, be sure your instrument is sharp, take heed to what your lathe is telling you, and discover a glad place.

Shape the Bowl’s Profile

Using roundnose scraper to begin shaping bowl
Begin shaping the skin profile of the bowl.

To form the skin of the bowl, we are going to join the 2 components you simply outlined—the sting of the foot and the underside of the rim.

Rounding out area around bowl foot
With the foot and rim outlined, use a roundnose scraper to spherical off the bowl’s profile.

Use the tip of a roundnose scraper to start rounding the profile. These are sweeping cuts, and dealing from the bowl’s backside to the highest works finest. After just some cuts, your toolrest might be too far-off from the reduce to be protected; cease the lathe and transfer the toolrest as wanted, conserving it about 1/4″ from the wooden.

Shaping bottom of bowl blank rim
Again, the roundnose scraper is used to ease the transition to the foot and below the rim.

The subsequent step is to spherical off the foot and rim. Start on the backside of the foot’s edge, and interact a reduce about 1⁄16″ into the wooden. Carry the reduce from foot to rim, all alongside the bowl’s form. When the sting of your instrument begins to chop the rim, ease off and pull the instrument away. A few cuts like this, and the strains of the foot and rim will mix into the bowl easily.

Rough turned bowl blank

The great thing about the roundnose scraper is you can reduce any a part of the bowl in any course and not using a catch—so long as the instrument is introduced flat on the toolrest, with the deal with slighted elevated, and moved with mild strain.

Cut Foot Recess

Cutting shallow recess inside bowl blank foot
A roundnose scraper is used to kind a recess inside the foot.

Mark a line 5/8″ (16mm) contained in the foot rim. Using a roundnose scraper, press the tip firmly into the middle of the clean. The instrument ought to start to create a gap. Stop pushing however keep the depth of reduce, then drag the instrument to the left to widen the outlet. Stop chopping simply shy of your 5/8″ line, and repeat this course of till you’ve reached a depth of 1/4″ (6mm).

Using skew chisel to create lip in bowl foot interior
The outer fringe of the recess is outlined by utilizing the lengthy level of a skew chisel, introduced flat on the toolrest.

Now use a sq.-finish scraper to flatten the underside of the recess. When the underside is flat, use the lengthy level of a skew chisel to make the final reduce on the exterior edge. Strive to make this reduce sq. and in a single push, stopping simply as you attain the underside.

Checking flatness of final cut bowl foot
Ensure the underside of the foot is flat, as it can develop into a short lived glue joint when the bowl is reverse-mounted for hollowing.

Use a sq.-finish scraper to show the foot flat, and use the sting of a small ruler to substantiate flatness.

Sand the Outside

Scrapers are straightforward to make use of, however it will probably’t be denied that they don’t shear the wooden like a gouge. As a outcome, scrapers are likely to tear endgrain and, in doing so, create the necessity to start sanding at a coarser grit. The most necessary factor to find out about sanding is that tough grits like 60, 80, and 100 form wooden and take away defects like torn grain. Grits 120 and finer are finest for eradicating the marks that the shaping grits create. All the torn grain and gear marks should be eliminated with the coarse grits earlier than transferring on to the finer grits.

Start with 80 or 100 grit. Tear a 2″ (5cm) strip of sandpaper and fold it to raised insulate your fingers from the warmth that can develop throughout sanding. Always hold the sandpaper in movement on the wooden, sand with the lathe turning at a sluggish velocity, and use your fingers to bend the sandpaper to the contours of the bowl.

Turn the lathe off earlier than you proceed to the following grit. Spin the bowl by hand and examine your complete floor. When you see solely the strains from the present grit and no tearout, transfer on to the following grit. Proceed in the identical vogue via the grits, as much as 220. The remaining sanding must be accomplished with the lathe off and within the course of the grain the place doable.

Sand your complete exterior of the bowl, however not the very backside of the foot. That floor ought to stay completely flat, and hand-sanding might spherical its edges.

Reverse-mount for Hollowing

Marking out wood blank to create a mounting block
With the bowl faraway from the lathe, a wasteblock is mounted. Transfer each the inside and outer diameters of the bowl’s foot.

Since we’re making this bowl and not using a chuck, the best way I reverse-mount the bowl for hollowing is to suit the foot’s recess onto a tenon turned from scrap wooden. The trick is to use glue to solely the underside floor of the foot (no glue within the recess). After you hole the bowl, it’s straightforward to half it from the scrap wooden.

The scrap wooden I exploit is a 5-1/2″ (14cm) size of dimensional 2″ × 6″ lumber. I exploit my bandsaw to chop off the corners. Mount a faceplate onto the scrap wooden, then mount it on the lathe.

Cutting mounting block lip with square scraper
Use a sq.-finish scraper to “part in” to the road from the periphery.

The object is to show a peg, or tenon, that matches snugly into the recess within the foot of the bowl. Start by truing the face of the scrap block, then switch the diameter of the foot’s recess and the skin diameter of the foot to the scrap block.

Cutting tenon on mounting block with point of scraper
Form a shallow spigot or tenon.

From the periphery, make plunge cuts with a sq.-finish scraper, as much as the outer foot line. Now draw a line on the periphery, 1/4″ from the entrance floor, and half all the way down to this line, ranging from the periphery and dealing towards the within pencil line. Ensure this space is flat, as will probably be the mating floor for gluing the wasteblock to the underside of the foot.

Final tenon cut on bowl mounting block
The tenon will match into the recess on the bowl’s backside.

To kind the tenon that can match into the foot’s recess, convey the toolrest to the facet and use a parting instrument to progressively form the tenon to a slight wedge. Now check match the bowl foot on the wedge.

Glue surfaces on mounting block and bowl blank marked
Apply glue solely to the wasteblock, on the floor that can mate with the underside of the bowl’s foot. Note that the writer has utilized oil within the recess of the bowl’s foot, so it is not going to adhere to the tenon on the wasteblock.

You need simply the highest of the wedge to slot in the foot’s recess. Now mark the purpose on the wedge the place the recess turns into too tight to advance any additional. Cut squarely from this mark to the underside of the tenon and retest the match. If the bowl doesn’t seat to the underside of the tenon, use 150-grit sandpaper to fantastic-tune the match. This will guarantee a cosy match of the bowl on the tenon.

Bowl blank and mounting block on lathe
The writer makes use of the lathe as a clamping system, urgent the bowl onto the wasteblock tenon utilizing the tailstock.

When the bowl matches on the tenon with no motion facet to facet, it’s time for glue-up. But first, I apply a coat of oil (on this case, Minwax Antique Oil) contained in the recess, each to the underside and the sidewalls. This will stop any extra glue from adhering to these surfaces and can enable a straightforward parting of the bowl later. I exploit 5-minute epoxy and apply a beneficiant layer to the scrap block round however not on the tenon. The thought is to use glue solely to the underside of the foot. Press the items collectively utilizing agency strain.

Hollow the Bowl

Drilling to the depth of your bowl
A Forstner bit is used to drill a depth gap.

When the leftover epoxy within the mixing cup is difficult, the bowl is able to flip. Confirm this by making an attempt to twist the 2 parts aside. If all the pieces feels stable, it’s protected to proceed.

Marking diameter and depth of bowl turning blank
Lines are drawn to point the depth and diameter of the primary “step.”

To decide the depth the bowl must be hollowed, measure the space from the highest of the foot to the highest of the bowl. Mine is 1-7/8″ (5cm). I would love the partitions of the bowl to be 1/4″ thick, so I subtract that from 1-7/8″ and decide I have to drill a depth gap 1-5/8″ (4cm) deep. I do that utilizing a Forstner bit with a chunk of masking tape on it to point the depth.

Marking for outer edge of final bowl shown
A sq.-finish scraper is used to plunge to the indicated depth at middle.

With the lathe operating, peer excessive fringe of the bowl on the lefthand facet, and use a pencil to mark the skin fringe of the bowl, minus the width of the rim. Then add one other line 1/2″ inside that mark. Mark the within of the middle gap at 1/2″ deep.

Wood shavings and progressive cuts in bowl blank
Then that depth is carried outward by making successive plunge cuts to the pencil line.

Start the plunge reduce on the fringe of the outlet, and carry that depth to the innermost line close to the rim. Now make one other 1/2″ mark on the edge and inside the middle gap and repeat the following plunge reduce, carrying the brand new depth from middle to the road close to the sting. When you attain the underside of the middle gap, go away the indent from the drill bit for now. This course of ought to have created a collection of “steps” main all the way down to the underside of the bowl.

Stepped tiered cuts made in a bowl blank
Make further depth and widening cuts till you attain the underside of the middle gap. A collection of “steps” ought to outcome.

Now swap to a freshly sharpened roundnose scraper to show away the tops of the “steps” till they’re all stage with the bowl wall. Stop the lathe and pinch the wall up and all the way down to really feel the thickness. Don’t simply look into the bowl—peer over it to gauge the form of the skin relative to the within. Strive to make the 2 contours comparable.

Smoothing out tiered interior bowl cuts
Use a roundnose scraper to take off the corners of the “steps,” leading to a clean curve from rim to backside.

You can transfer the scraper in both course contained in the bowl—from rim to backside or backside to rim. Make the highest of the bowl wall a thickness that feels proper to you, then carry this thickness to the underside. Once the partitions are near their completed thickness, reduce away the indent left by the drill bit, mixing this space with the sidewalls. It is necessary to cease chopping the underside as quickly because the indent is gone.

Final rough cut interior of bowl blank
A few gentle passes with a freshly sharpened scraper will dramatically scale back the quantity of sanding wanted.

Again, since we’re utilizing solely scrapers for this undertaking, some coarse sanding could also be required to take away tearout. Sand via the grits, as you probably did on the skin of the bowl.

Alternate Foot Design

Bowl blank with inlaid foot

Here is an alternate foot thought that appears nice when utilizing contrasting woods. It could be produced simply, with just some variations from the fundamental bowl course of.

Cutting inlay circle in base of bowl blank

Separately (not proven), flip a hoop in a contrasting species. Rather than forming a foot with a recess within the center, make a groove to simply accept the foot ring you’ve turned.

Mounting bowl on lathe using inlay as tenon

Ensure your chuck jaws will match into this groove. Mount the bowl for hollowing utilizing a chuck, both in compression or growth mode.

Installing contrasting wood inlay into turned bowl

Hollow the bowl as described within the article. Glue the ring into the groove for a chic foot.

Part Bowl from Wasteblock

Preparing to remove bowl blank from mounting block
With the bowl hollowed and sanded, half the bowl from the wasteblock.

To take away the bowl from the wasteblock, it’s a easy matter of parting via the glue joint on the foot. But this must be accomplished slowly and punctiliously. I convey up the tailstock with a big cone middle, wrapped in electrical tape, to help the bowl with out marring it.

First parting cut between bowl blank and mounting block
First, half in simply to the left of the glue line. Then, with the tailstock supporting the bowl (not proven), make a remaining parting reduce angled inward to take away the glue joint.

Use a parting instrument to start eradicating scrap wooden from behind the bowl, below its foot. Remember, the foot is 5/8″ huge, so these cuts should go not less than that deep so as to separate the bowl from the scrap. Sneak up on the glue joint, in order that the ultimate skinny reduce simply removes the glue line the place the bowl and scrap meet.

Inner edge of bowl marked for removing from mounting block
Finally, take away the tailstock and pull the bowl off the tenon.

Guide the instrument in at a slight angle towards the bowl, leaving the skin of the foot a bit greater. Once you see the foot of the bowl finish and a tiny little bit of the scrap emerge, cease chopping. The bowl can now be faraway from the lathe by retracting the cone middle and pulling the bowl off the tenon by hand. The oil contained in the foot’s recess ought to have stopped the tenon from adhering to the bowl. I like to make use of a hardening oil, comparable to Minwax Antique Oil, as a bowl end. In this case, an oil end is finest since I had already utilized oil within the backside recess.

Scott Belway is a woodturner based mostly in British Columbia, Canada.

Source link


Please enter your comment!
Please enter your name here