LumberJocks

Mancala Board?

  • Advertise with us

« back to Power Tools, Hardware and Accessories forum

Forum topic by Shane posted 10-09-2015 12:19 PM 1638 views 0 times favorited 17 replies Add to Favorites Watch
View Shane's profile

Shane

293 posts in 1272 days


10-09-2015 12:19 PM

I want to make a Mancala board game but the holes are generally 2” concave cuts into the board. The best price I can find on a round nose router bit big enough to do the job is $55. Any other ideas on how to make a concave half circle in wood that is 2” in diameter?


17 replies so far

View Kazooman's profile

Kazooman

624 posts in 1413 days


#1 posted 10-09-2015 12:25 PM

They wouldn’t be perfectly hemispherical, but you could use a 1/2” (or larger) core box bit in a router with a guide bushing and a template of the correct size. Cut the circumference and then hog out the middle. The centers would be flat bottomed, but you should still be able to remove the pieces easily.

View SirIrb's profile

SirIrb

1239 posts in 691 days


#2 posted 10-09-2015 12:27 PM

custom grind your own from a spade bit and use it in a drill press.
EDIT: You will want to remove a good bit of the bits shank to give it less chance of deflection. Make sure you make it very sharp.

-- Don't blame me, I voted for no one.

View WoodNSawdust's profile

WoodNSawdust

1417 posts in 637 days


#3 posted 10-09-2015 12:47 PM

MLCS one for $29.00 with free shipping and no sales tax.

-- "I love it when a plan comes together" John "Hannibal" Smith

View Shane's profile

Shane

293 posts in 1272 days


#4 posted 10-09-2015 01:02 PM

Link failed… But if it’s the same one I saw yesterday it’s out of stock until December

View Shane's profile

Shane

293 posts in 1272 days


#5 posted 10-09-2015 01:30 PM

The more I think about this the more I think I’m just going to need to do it with a forstner bit and give up on the concave shape. It won’t look as nice but I don’t have a plunge base for any of my routers (Hitachi M12VC and two older Craftsmans).

View sras's profile

sras

4391 posts in 2590 days


#6 posted 10-09-2015 01:36 PM

You don’t need a plunge router to use Kazooman’s process. Just tilt the router onto the template. The key is to make multiple shallow cuts. I usually go for a little over 1/8 inch at a time.

-- Steve - Impatience is Expensive

View bigblockyeti's profile

bigblockyeti

3666 posts in 1181 days


#7 posted 10-09-2015 02:20 PM

I used this bit for making the radius between the sides and bottom of several trays: http://www.amazon.com/gp/product/B0052IFVM2?psc=1&redirect=true&ref_=oh_aui_detailpage_o01_s00. It was cheap and after a couple dozen trays it is certainly worse for the wear, but for the price I can consider that acceptable. If you’re trying to make the width/diameter of the pockets for the glass beads 2” at the top, you would have to plunge a full 1” into the wood to achieve that dimension with this bit. The mancala boards I’ve seen before I don’t believe were that deep as the wood was closer to 3/4” thick if I remember correctly. As mentioned already, several shallow passes are much safer for you, the work piece and the life of the bit.

View Shane's profile

Shane

293 posts in 1272 days


#8 posted 10-09-2015 02:52 PM

That’s a really good point that I hadn’t considered. Probably better to use a smaller bit to do the edges and then just hog out the middle with a straight/flat bottom bit as Kazooman originally suggested.


If you re trying to make the width/diameter of the pockets for the glass beads 2” at the top, you would have to plunge a full 1” into the wood to achieve that dimension with this bit.
- bigblockyeti

View Shane's profile

Shane

293 posts in 1272 days


#9 posted 10-09-2015 05:13 PM

I’m really kicking myself for not buying the plunge base when I bought my router. It’s cheaper to buy a new one with the base than it is to buy a base for my existing one…

View splatman's profile

splatman

557 posts in 860 days


#10 posted 10-09-2015 07:40 PM

How ‘bout a router bit in a drill press at the highest speed? Clamp the workpiece, set the depth stop, and plunge away!

View Yonak's profile

Yonak

979 posts in 982 days


#11 posted 10-09-2015 09:14 PM

Build a jig that’s a circular hole 2” larger than the diameter of your circular router base plate. Devise a way to clamp the board to the jig with each pocket centered in the hole. Ease the bit into the board, using Steve’s tilt method (hold on tight), go ‘round the circle and go back and forth, hither and thither, across the bottom flat, and finish by sanding.

It shouldn’t be too difficult. You may have to cut the holes before you cut the board to size in order to have enough to clamp. ..Or you may want to use the extra wood, outside the finish size to screw the board to the jig. Good luck, and have fun. Be sure to report back about what you did and how it fared.

View Kazooman's profile

Kazooman

624 posts in 1413 days


#12 posted 10-09-2015 09:53 PM

I really should have recommended using a dish router bit. It cuts a curved profile on the edge like the other bit, but has a flat section in the middle. That would give you the nicely curved edge for your cups, but make it easier to create a flat bottom without changing to a straight bit.

I know that you would like to make your game board without incurring any major expense, but you really need to come over to the dark side of woodworking like most of us have. Every new project is seen as a perfect reason to buy some new tools. For example, you could probably buy a nice mancala board, complete with the stones, for about ten bucks. On the other hand you could spend twenty bucks for a nice scrap piece of rosewood or mahogany, fifty bucks for a carbide dish router bit, thirty bucks for a a set of router bushings, and at least $250 for a nice variable speed plunge router. Add in your time, materials for the jig, sanding and finishing supplies, and the choice is clear. You simply MUST build your own. I say go for it. Please post pictures of the finished board and of your new tools when you have completed the project.

View Shane's profile

Shane

293 posts in 1272 days


#13 posted 10-09-2015 11:52 PM

I’m fully on the dark side but I’m low on cash at the moment. :) I will definitely post pics when I’m done.

View oldnovice's profile

oldnovice

5721 posts in 2829 days


#14 posted 10-10-2015 12:00 AM

I am with Steve as that is the technique I used until I got a plunge base! The plunge base makes it esir but the tilt in method works too.

I would suggest using a larger straight bit to clear out a lot of the hole and then switch over to the radius bit!

-- "I never met a board I didn't like!"

View Ghidrah's profile

Ghidrah

667 posts in 683 days


#15 posted 10-11-2015 02:55 AM

I used a core box pattern bit on this one but have also used a bowl bit

-- I meant to do that!

showing 1 through 15 of 17 replies

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com