Making a Large Connect Four - How to make the discs?

[Acrobat]

Hi, I've been asked to make a large Connect Four game. So I have the materials (to keep costs down) the discs are going to be cut from a 12mm thick mdf sheet.
I have a hole saw that gives 90mm discs but it also gives a smaller hole from the centering drill bit of about 5-6mm. Anyone have any ideas on how I can get the large discs cut without the small holes in the centre?
I need to do 42 discs so it'll be slow going. I don't have a lathe nor know anyone who has one where I live as I thought that may be a good idea.
Anyone have any thoughts? I'm racking my brain to find a quick way, if I can find a nice large dowel 90mm thick then I'd simply cut it down to 12mm thick on the drop saw but the local big box store only has small sized dowels.

 

[Tyler Ernsberger]

Cut a template with your 90mm bit.  Take out your center pilot bit and use your template clamped on top of the 12mm and it will allow to cut out the circles with out a pilot bit.  The template will guide the bit without a center bit. 

 

[semenza]

I think the large dowel idea might create disks that would be prone to breaking with the grain if / when dropped.

For cutting them out how about a router with a template?

Seth

 

[bkharman]

I made one a few years ago. I use styrofoam covered with black or red duct tape. So much better and looks great! 

Cheers. Bryan.

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[Roseland]

+1 for using a router and template.

Andrew

 

[DiscoStu]

I recently made something similar and went for the router and template option. Another option would be a bandsaw or scroll saw but I think the router will give a better result. I have made up a circle jig for my bandsaw so if you need to make a lot then I'd suggest doing the same if you go the bandsaw route. The bandsaw does leave a pin hole in the middle of the disc.

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[Kev]

I've uses a hole saw with the drill bit reversed and the collar set way back. Then ever so carefully cut the circles for a standing position bent over. This was for four only and they were about 40mm.

I didn't enjoy it.

I think the method could've worked ok on a pedestal drill. I didn't have one handy at the time.

 

[GhostFist]

Bandsaw, or router with template, a good jigsaw with a trammel will do it as well but most jigsaws will suck at it

 

[budderbean]

This is one I built a few months ago for a friend.

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[jeh]

I'n not certain MDF would be the best choice for the discs. The edges may not be able to take the abuse of being continuously dropped. A hardwood could be a better choice.

 

[Gregor]

I'm racking my brain to find a quick way, if I can find a nice large dowel 90mm thick then I'd simply cut it down to 12mm thick on the drop saw but the local big box store only has small sized dowels.

Do you know someone with a lathe?
He could turn you a nice cylinder the diameter you need which you then can cut into slices the thickness you need...

 

[bkharman]

I am telling you, styrofoam with red and black duct tape works very well. If it dings up, who cares. Make another one in 5 minutes. If it falls on your toes, who cares.

Trust me, I went through this topic in my head last year.

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[ear3]

Man. Who knew life sized home made connect four was a thing?

 

[flair woodworks]

My first choice would be the hole saw without the pilot in a drill press. Second choice would be a table saw and circle jig. Third choice would be a router and template.

 

[Acrobat]

Wow thanks for all the suggestions guys.
Butterbean, that looks about the size I was asked to make. Yours is sweet! I see you have a dowel sticking out at the bottom left, is this for removing, so the discs can fall through?
BKHarman, styrofoam, interesting idea but since I have the mdf sheet and cut a few already I better keep going.
jimH2, yeah hardwood would be a better choice just trying to keep the price down for her so a sheet of mdf was chosen. I'll paint them when cut so they will look better. 12mm mdf should take some abuse, I dare say the discs will more than likely get lost before damaged.
I think either I use one disc I've already cut as a template and route around it (but 40 odd will sure take a while,  or remove the centre drill piece and cut them on the drill press as was suggested by Chris. Think I'll try that.

 

[hopper]

Why not take advantage of the center hole when using a hole saw. You could use the holes (enlarged) to store the disks when not in use. eg drill holes out to 1/2" then stack them on a 1/2" dowel rod mounted vertically in a base. I don't think the holes would look that bad.

 

[Acrobat]

Hi Hopper. I had thought about that actually.  Still thinking about doing that or not. I'd need to enlarge the centre hole to fit a dowel, not sure if it would look ok or not really. Thanks for the suggestion.

 

[WastedP]

I like the idea of using foam, but I would cover it with heat shrink film, like they use for model airplanes.  Then you could carve heads and tails in the foam and the relief would show through without falling apart.

 

[jeh]

I'm racking my brain to find a quick way, if I can find a nice large dowel 90mm thick then I'd simply cut it down to 12mm thick on the drop saw but the local big box store only has small sized dowels.

Do you know someone with a lathe?
He could turn you a nice cylinder the diameter you need which you then can cut into slices the thickness you need...

I like that idea.

 

[jefL]

A bit late to the discussion I know but I made one recently for my daughter's wedding party. The discs were cut from 3/8" ply and I used a 5" hole saw, without the pilot drill, in a drill press. I doubled the ply sheets and cut two at a time but it was still slow going to make the 36 I needed (C4 was 7 x 5 holes to fit a quarter sheet of ply).
The main thing to watch is the heat. I stopped a couple of times to allow the hole saw to cool.
Also don't rely on holding the ply by hand, there is a lot of torque transfer in a 5" hole saw, clamp it to the table with a quick-clamp with the leading edge against the column.