The best way to cut a slot in round stock?

svendole

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Joined
Feb 16, 2015
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9
Hi everyone in FOG,

I got my first Festools  about 8 mths ago, and I am a happy amateur in woodworking.
I only just registered as a member, but over the last months I've read almost all the posts in FOG with great pleasure. I've already learned a lot, so thank you for all the good advice.

Now I'm facing a challenge: for a project, I want to make a slot in a round stock, looking like the attached picture.

The round stock is 43mm in diameter, 200mm in length. The slot has to be 9mm wide, 150mm long and absolutely centered.  The end of the slot should actually be cylindrical, but I couldn't figure out how to draw that in SketchUp.

[attachimg=3]

My idea is to start out with a longer piece, cut the slot in the middle and then cut off one end to open the slot. I believe this would allow me to hold the stock safely in a vice. But how do I cut the slot?

My Festool tool range consists of a OF1010 and a TS55R, plus a CMS table with inserts for both. I also have some tracks and a homemade MFT.

I am going to produce 12 identical pieces, so setting up a fixture of some sort could surely make sense.

I guess I could do it with a router bit (e.g 6.5mm) and cut along the inside of a square template, but I cannot do the depth of 43 mm from one side, so I would have to turn the stock around, and that will give me a challenge with the alignment.

Another way would be to use the TS55, which can cut all the way through but how do I then make the end of the slot?

Unfortunately I don't own a bandsaw!

Anyone made something similar?

Thank you for your comments and advice

Ole

Edit: Try again with the picture:
[attachimg=1]

 

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Cut two slots with a hand saw, and chisel out the waste in the middle. Safest way and I can't think of an easier way.
 
Welcome to the FOG!

Not sure how well this might work in practice.  What if you used your router, but first use a drill bit that matches your router bit size to drill a through hole centered at the bottom of the slot?  That would be a reference to use to align your router bit when you do both sides.

Mike A.
 
Hi Svend Ole [welcome]

Can you make a jig and fixate the round stock to the jig and cut it on you table saw (TS55R in CMS).
Turn the stock 180 degrees and do it again.
Chisel out the last bit in the bottom of the slot.

(Sorry guys it's easier for me to explain in danish  [embarassed]

Hej Svend Ole, velkommen
Kan du fiksere et stykke længere rundstok til et bræt og skære slidsen á et par gange på CMS'en?
Du får så en skæv "bund" i slidsen, men så kan du dreje rundstokken 180 grader og tage den en gang til fra den anden side. Den sidste rest i bunden af slidsen kan du så tage med et smalt stemmejern, en fil eller måske en håndsav?)

Kind regards / Med venlig hilsen
Henrik

 
Take a look at a commercial jig called the GRR Ripper. 

This is basically a block that is used to hold and enclose stock that you are passing over a tool such as a router bit or saw blade.  One of their videos (which unfortunately I cannot locate) shows using the block to cut a groove in round stock on the table saw.

If you are producing a number of these you should be able to fashion a custom block that can be used in a similar way to secure the stock as you make the cut.

Jeff
 
Thanks a lot for the inputs and the welcome!

Some really good ideas came up, but I guess I should have mentioned that this part will be very visible and the edge of the slot must be as close to perfect as possible - straight and sharp.
I don't trust my skills with a handsaw to do that, and also sawing with the TS55R I don't see how I can avoid some tear-out at least on one side - and if I turn it over as suggested I would even have the tear-out on both sides.

So I guess I am going to try the routing, and the idea of an indexing hole sounds good.

I will do some experiments and report here on the outcome  (could take a week or two, though)

Thanks
Ole
 
This is a common enough procedure in the average metal shop.  Most of the times I see it done using a vise in a vertical mill.  It's pretty easy to set up when you have a center-closing vise and a cutter of the right diameter.

You made no mention of a lathe, but if you have access to one, I would suggest turning your blanks yourself.  That way you can start with square stock and leave a square section on each end that you will cut off of the final piece.  The squared section gives you a flat face for indexing.

Now, if you're cutting the slots on already trimmed to size round stock, I think I would go about it with a table saw jig.  Make a box, sized wide enough so that the pieces fit snug in a line and use a dado stack to cut the slots.  I would pin the round stock into the jig with 23 ga pins.  Jig trick, for pinning things into jigs you will want to remove later, use pins about a 1/2" longer than needed and fire them through a pink eraser.  I usually leave the eraser hanging on the pin head if possible, it reminds me to pull the pin and it protects me from the end of the pin poking me.  If a set of test cuts didn't turn out sans tear out I'd look at filling the voids in the jig box with something like machinists wax.  It's hard enough when solid to act as a nice backer but it's still fluid enough when casting to fill the voids where the round edges would be contacting. 

 
I'd try to find someone with a bandsaw. I'd drill a hole with the correct diameter at the end of the slot and then bandsaw the slot. Doing a bunch, I'd make a holding jig.
 
I would drill a hole the correct diameter to get the rounded slot end. To cut the slot, you could drill a 43 mm hole in an appropriately sized piece of square stock then insert your dowel vertically and cut the slot on a table saw. Hope this makes sense.
 
RL said:
Cut two slots with a hand saw, and chisel out the waste in the middle. Safest way and I can't think of an easier way.
                                                                                                                                                                                                I agree..The only way. If you don't have a chisel ,finish with a coping saw.
 
Thank you to all for good ideas and input.

This is how I did it:  I cut the round stock in little longer than double length of what I needed. Then drilled a 9mm hole in the center.
I aligned the piece with my track, set up two stops and aligned the 9mm router bit with the drilled hole.  Starting from the hole, I cut the slot in the two directions. Then turned the piece around, aligned again with the hole and routed from the other side.

The two slots didn't meet exactly in the middle every time, so I had to take a 10mm router bit, plunge it deep in and route the inside without damaging the edges.

After that I cut the pieces into halves - because of the longer than needed length I could cut away the center hole.

At the end I had 12 nice round stock pieces with a slot that could slide over a 9mm plywood wall, with an absolutely nice and tight fit.

The outcome was this 30 bottle wine rack, built to fit inside an Ikea cupboard, as a present to my son.

Some pictures:

[attachimg=1]

[attachimg=2]

[attachimg=4]

[attachimg=3]

Regards
Ole

- now playing with my latest purchase - the Domino [drooling]
 

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Ok, the pictures didn't appear in the right order but I guess you can figure it out. Further I missed the most important picture, sorry,
here it goes:

[attachimg=1]

Ole
 

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Very creative solution for a great looking wine rack...so did you fill when you gave it to him?
 
svendole,
Glad to see the drill idea worked out.  Great looking project and a nice mod! 

Mike A.
 
Clever design and great project. Festool rails to the rescue - again!
 
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