# Help with Edge Grain Cutting Board - Thickness and Suspension



## Tool Agnostic (Aug 13, 2017)

I could use some advice for the design of an edge grain cutting board. 

BASIC REQUIREMENTS:

I would like to build a nice cutting board that will fit across a farmhouse sink and not fall in. The farmhouse sink has a single basin like a small bathtub. The cutting board should be able to slide left and right while fitted across the sink. When pushed against one side or the other, the cutting board should be level with the granite counter. The granite counter partially covers the top edge of the sink on three sides.

The cutting board will be 12 inches wide by 18 inches deep. The granite counter is 2 centimeters above the top of the sink. The sink is approximately 30 x 18 inches.

The cutting board should be flat and stable when suspended across the sink or if placed on a countertop. Depending on the design, I would make some kind of feet with rubber inserts. 

DESIGN PROBLEMS:

* Weight?
I originally wanted to make a thick, massive cutting board until I realized how much it would weigh. My spouse won't use it if it weighs too much. Now I wonder how thin I can make it (2 cm?) and still be strong and stable.

* How to Suspend the Cutting Board over the Sink? 
I thought about trying a cove cut on the table saw for the front and back of the sink, so that the solid cutting board would curve over the front and back edges of the sink. Another option would be to attach thick wood strips to the bottom of the cutting board. They would press against the inside front and inside back of the sink, and could hold the rubber feet on the bottom. (It just occurred to me that I could rabbet the bottom edges as another solution, but it might not look as nice, and a thick cutting board might weigh too much.)

* How to match the curves of the sink edges?
Related to the above. When the cutting board is pressed against the left or right edge of the sink, it must thin to 2 cm on the edges, to accommodate the sink/counter interface. 

* How to match the wide flat corner curves of the counter?
How do I copy the wide corner curves of the counter, so that the cutting board corners fit perfectly.

* Can I get by with my existing tools? ... or does it make sense to buy something?
I have a great table saw with a superb Forrest blade. I like to think that it cuts nearly as clean as a jointed edge. I also have a nice 8 inch dado set. 

I do not have a bandsaw, jointer, planer or router table. I have a very sucky, 1970s Craftsman 1-speed handheld saber saw. It is hard to control. I have an old, cheap 1970s Craftsman drill press with various bits including hole saws, sanding cylinders, specialty bits like spades, Forstners, etc. 

I have an old 1980s Black and Decker 1.25 horsepower fixed base router with a 1/4 inch chuck. I have the usual hand tools, including a few basic chisels, hand planes (which I am not yet skilled at using), and handsaws. 

I do not mind buying the right tools, bits, or jigs (or making them) if it makes sense, but I try to make do with what I already have. I will trade time and labor to save on tools, but I don't want to compromise on quality. If it's time to buy a tool, then it can happen.

HERE ARE MY QUESTIONS:

1. How thick (or thin) should I make a 12 x 18 edge grain cutting board that is strong enough to suspend itself by the long ends, and still hold a 40 pound turkey for carving? Remember, the cutting board can't weigh too much, or my spouse can't lift it and won't use it.

(Should I change plans and go with a side-grain cutting board instead? Would it be stronger?)

2. How would you suspend the cutting board over the sink so that the flat top aligns with the granite counter, and the cutting board won't fall into the sink? 

3. How would you accommodate the left and right side of the sink, so that the sink won't block the cutting board from reaching the left or right edge of the counter?

4. How would you copy the flat curve of the counter corners and match them on the cutting board's corners? 

5. I am a novice woodworker. Am I asking the right questions? Have I made some invalid assumptions? 

What would you change to help me build a very special cutting board for my spouse? 

Thanks in advance to all who respond!


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## jeremymcon (Oct 16, 2014)

I feel like you're over thinking this. Make it 3/4 thick - any thinner and it will tend to warp and won't be very sturdy. If you want it to fit the curves of the sink, make the corners curved! Make a template from a piece of cardboard, trace it onto the corners, cut close to the line with a hand saw ( and saw, jig saw, whatever - its not. Much wood to remove), then file/rasp/sand to refine it.

Make a cross piece (batten) for each end to keep it centered on the sink. Attach it with screws, using slotted holes at the ends to allow the board to expand and contract if it is being attached across the grain. Or you could just glue it if it's being attached with the grain oriented in the same direction as the rest of the board. 

If you're going to use rubber feet screw them on with the same screws you're attaching the battens with. Or just attach them to the battens. Or don't use rubber feet. Use stainless screws.

If it *has* to be completely exactly flush with the countertop, I'd just cut a rabbet on the two sides that support it on the sink. Don't go too thin though, as (the way I use them, anyway) cutting boards can take some force sometimes.


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## TomCT2 (May 16, 2014)

couple of thoughts -

I've had/used both end grain and edge grain maple cutting boards. knife-nuts will insist end grain is 'the one and only' but frankly I've not seen any significant difference on my knife collection.
I'd go with edge grain for two reasons:

1. it's a lot easier to make - doing all those little end grain blocks requires precision and potentially a planer to get the required consistency in size.
2. less chance of warp/sag over time especially suspended over the sink.

1-1/4 to 1-1/2 would be thick enough from a structural point; "good quality" cutting boards - the heavy ones - are typically 2 to 2-1/2 thick.

did you want the cutting surface (essentially) flat/level with the granite top? if so then the only support available is the top ledge of the sink. is there a perfectly flat surface along the back (as opposed to no space other than the radius into the sink...)

the cutting board could rest on the granite itself at the back, and built up thickness to ride on the sink rim at the front. 
in either case you will need built up 'cleats' on the bottom to keep it located over the sink. these can be shorter on the ends allowed the sides of the cutting board to reach or even slightly over lap the granite top.

one problem will be keeping the wood board from 'sitting in water' - you'll need some kind of plastic "feet" to provide at least a 1/4" gap between wood and sink/granite.

I'd also suggest making a prototype from cheap stuff - pine perhaps - to get the design & function tweaked before chopping up a more expensive wood. with cleats and feet and sliding . . . one potential problem is having it bind up / skew / stick.


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## jeremymcon (Oct 16, 2014)

After re-reading your post a few additional comments - you said "edge grain" cutting board, but then you mentioned "side grain" also. If you're planning to make an *end* grain board that you want to suspend over the sink, and also want to be lightweight - don't. Wood likes to split in the direction you'll be placing force on the board. Do a conventional side grain board.

As for the battens I mentioned - just don't make them the full width of the cutting board, and they won't be in the way when you slide the board to the side. 

Is your counter top about 3/4" above the top of the sink? If so no rabbet will be necessary - just let the full 3/4" thickness of the board sit above the sink. If you need to use a rabbet around the whole board to bring it down flush with the counter, you'll have to chisel/saw some material from around the corners to accommodate the curved lip of the sink, or simply make the rabbet at the side extra wide.


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## dhtaylor (Oct 16, 2017)

I was just thinking about the same thing when you said: "Make a cross piece (batten) for each end to keep it centered on the sink. Attach it with screws, using slotted holes at the ends to allow the board to expand and contract if it is being attached across the grain."

I had a one piece deep stainless sink (used to bathe the boys in it) years ago, and I had an old kitchen cabinet with a dough board in it. It had battens on the bottom to slide on the runners in the cabinet. I also had about an inch around my sink, and the dough board fit right in there really well. It is 22 1/2" x 16"


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## Tool Agnostic (Aug 13, 2017)

Just a quick note to say thank you to everyone for their helpful ideas. I meant "end grain" when I wrote "edge grain", but hopefully everybody got it. I am a novice, still trying to get the terminology right. I learned a lot from your comments, and will definitely make some prototypes before embarking on another maple/walnut/(maybe cherry, too) cutting board. I had not thought about the "wood resting on water" issue.

If you think of anything else about cutting board design, don't hesitate to post it here. If I have more questions as I design and build the cutting board, I'll post them here, too. I'll post a final photo when it is done. It may take a while - my spouse always has a large honey-do list for me.

-----

Just for kicks, here is are two photos of my first cutting board, which I finished in mid-September. I know it is a junior high school project, but it is my best work so far. It was designed to fit a cutting board slot at my in-laws' home. The previous owner had stolen the original cutting board. The hardest part was getting half-round edges to match the slot. I discovered that you can't use the bearing to follow the edge with a quarter-round router bit, because when you flip the cutting board over, the bearing goes in too far due to the previous cut. I had to build a crude router table out of scrap plywood.

Again, thank you for all your advice.


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## Larry42 (Jan 10, 2014)

The proposed size won't be too heavy even is made 32mm thick. End grain should be thicker as it will be inclined to split. You can cove cut the ends & sides if you want on the table saw. Fasten a diagonal fence to the saw and raise the blade by small amounts to cut the coves. Be very careful to go slow and maintain tight control, this is a *risky* procedure. Use a push block. Leaving 12mm thickness around the edges will support the board within the sink. The 20mm drop into the sink should be enough to keep it located. Don't cross grain as the board has been done in the photos, it will cause cracking if it gets wet. Make a test part out of cheap material to check your process first.


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## Tool Agnostic (Aug 13, 2017)

New Question:

How do I match the inside corner of the counter? 

I would like to capture the "quarter round" shape of the granite counter and match it with the corner of the cutting board. I would like the corner of the cutting board to fit "snug" against the radius of the granite counter corner.

How would you figure out the radius of the corner? Is there an easy way to make an accurate, matching template out of cardboard or scrap wood? How would you lay it out on the actual cutting board?

What is the best way to make the cut out on the corners of the cutting board itself to match the counter radius in the corners of the cutting board? How would you do it?


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## TomCT2 (May 16, 2014)

cardboard, pair of scissors, snip-testfit-snip-testfit-snip&repeat.

then trace it to the wood, saw off the biggest chunks, rasp/microplane/sandpaper to "close" - sand/testfit/sand/testfit/sand&repeat.

magic incantation optional but not required.


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## Tool Agnostic (Aug 13, 2017)

TomCT2 said:


> cardboard, pair of scissors, snip-testfit-snip-testfit-snip&repeat.
> 
> then trace it to the wood, saw off the biggest chunks, rasp/microplane/sandpaper to "close" - sand/testfit/sand/testfit/sand&repeat.
> 
> magic incantation optional but not required.


This is just what I needed. Thanks. 

I had hoped for a more scientific approach that would work better for a woodworker with limited skills. I don't have much confidence in my ability to freehand the refinement of those perfect shapes (like the rounded corners) after the rough cutting is done. What you have revealed is that I need more practice until I can gain that confidence. I will practice on scrap until I am confident that I can get it right.


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## Terry Q (Jul 28, 2016)

If you make a paper pattern you are happy with, copy the pattern to a piece of preferably 1/4 inch hardboard or plywood (any thickness will work, but it is easier smoothing the edges of thinner material). Cut just outside the line with a jig saw, or band saw, or scroll saw, or even a coping saw. Sand the edges smooth and make sure it fits your sink. Trace the pattern on your cutting board and saw just outside the line. 

If you have a router table, get a flush trim router bit (the bearing is at the end) with cutting length at least as long as your cutting board is thick, attach your pattern to the top of the cutting board and run the bearing along the pattern smoothing the edge of the cutting board. A little hand sanding and you’re done.

If you don’t have a router table it’s a little more complicated with a hand held router, but it still starts with a pattern. If you get the pattern made and if you need more help, ask.


In woodworking there is always more then one way to accomplish something.


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## Tool Agnostic (Aug 13, 2017)

Terry Q said:


> If you make a paper pattern [...]


Thank you for this helpful advice. 

I have a 1980s Black and Decker router, but it has a 1/4 inch collet and is only 1 1/4 horsepower. I wonder whether it can drive a flush trim router bit on a moderately thick hard maple cutting board without issues. I don't have a router table, although I made a crude one for a one-time use. The router table fell apart the instant I was done with it. 

I also have a 1970s Craftsman one-speed handheld jigsaw (sabre saw). It sucks. It vibrates a lot and is very difficult to make smooth cuts. 

I just picked up an old Delta 890 bandsaw. It is in great shape. I think it might be the best way for me to cut the cutting board corners unless someone suggests a better way. 

(Maybe Santa will bring me a nice 1/2 inch router and a router table to go with it, but I want to finish this project before the holidays.)


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## Terry Q (Jul 28, 2016)

Bandsaw is probably the best possible tool for cutting you board.

How thick is your cutting board? You probably can’t get a 1/4 shaft bit longer then 1 - 1/4 inches. If it’s thicker then that then you can use a pattern bit (bearing in the middle) and a hand held router. Mount your hardwood pattern on top as before, set the depth so bearing rides against pattern and cut partially through your cutting board. Remove the pattern and run the bearing against the already routed part of the edge to profile the remainder.


In woodworking there is always more then one way to accomplish something.


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## TomCT2 (May 16, 2014)

mewonders if there's not a bit of overthinking afoot . . . 

there are "circle templates" - they come in all sizes. you can trace a circle on stiff paper, cut it out, check it for size.
there are also "compasses" to draw circles.
and not every rounded corner in granite is a perfect circle . . .

doing this with power tools carries a large risk of a booboo - at the end point of all the effort comma no less.
and especially if one is not thoroughly experienced in using the tools....

it's two corners - rough it out and sand it down by hand. sanding block+coarse+medium+fine grit. it could take 15 minutes per corner. not even close to rocket science and much less likely to slip and create an ah-sh moment.


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## Tool Agnostic (Aug 13, 2017)

TomCT2 said:


> mewonders if there's not a bit of overthinking afoot . . . [...]


Thank you for your thoughts and recommendations. You are 100% right. It's true, I need to plan the entire process before I start on a project. I don't like surprises.

Some of my friends just grab some wood and get going, improvising as they go. I wish I could be more like them, with high confidence and spontaneity, but I am not. What little confidence I have only comes from careful planning. That's the way it is.

My current plan is to cut the corners slightly wide (in the waste area) with the bandsaw, and then use hand tools like rasps and files, and after that sandpaper with a sanding block to do the final smoothing and perfect the corners. I would like to do all four corners, so that the cutting board will look symmetrical and fit in both front and back orientations.


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## TomCT2 (May 16, 2014)

if you go with end grain design, the grain will be vertical and you'll be rasping "across" the grain on the corners - I would anticipate you'll want to do most of the finish work with sandpaper after roughing off the big chunks.

not sure I'd do the "reversible" thing - the aisle side of the sink lip is wider than the faucet side - I'd be tempted to overhang the sink in the front by 1/4 - 1/2"


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