# can you taper Multi-sided projects with glue joint bits?



## Sallen1215 (May 10, 2014)

I am working on a lighthouse project for a customer and up til now i have been using the normal design of 6 sides with 60 degree miters done with a table saw or a track saw, i want to streamline this process and i saw these bits, I also decided for more "realism" i should go with a 12 sided which would be a 15 degree cut on each "stave" so with that said here is a picture of what i am making and it is 12 sides starting at 4" at the base and ending up at 2 3/16" and the glue surfaces is driving me nuts. Any help would be appreciated.

Stephen Allen


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## subtleaccents (Nov 5, 2011)

I have just used the basic 15 or 30 degree chamfer straight edge bits for the few lighthouses I have made and they worked well.

Actually made a template of the tapered part and just ran the router around the template. Never used the table saw.

If you use 5/4 lumber you can turn the glue up to have a round lighthouse. That is closer to the original design than 6 or 12 flat surfaces. I know that is probably over kill, but that is my major problem.


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## Cherryville Chuck (Sep 28, 2010)

The glue joint bit should work as long as it is used perpendicular to the edges I think. Have you considered using a spline joint instead? Same method applies.


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## Sallen1215 (May 10, 2014)

I had thought several times about just doing a 30 degree v bit and only using the 15 degree side but was wondering about the multiside bit as an option, i love when it looks great in design software but as we all know sometimes the real life product is not so much, This lighthouse will stand 6' tall with all the components and is made from 3/4 baltic birch ply, if you have any photos of your suggestions i would comely them whole heartledly


Thanks

Stephen


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## Semipro (Mar 22, 2013)

Hello and welcome to the forum Stepehen


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## routergieck (Feb 11, 2013)

Hi Stephen
I glued up a 12 sided display stand (you can search it under "segmented circle arrowhead display stand) which I cut on the table saw. Th mitered joints fit very well but the problem I had was holding everything together for the glueup as the angles were lower. Your lighthouse should be easier to glue with the higher angles. There are charts available to determine the angle you have to cut for a compound miter. I googled "compound angle calculators - miter and butt" where you simply have to enter a run, rise, and number of sides. Using your measurements I determined the top and bottom circumference and then the diameter to get the "run". Your angle changes with height so I used 16 inches as an example and got the bevel angle at 14.65 degrees and the end angle at 3.25 degrees which are the two measurements you need to make the segments on the saw. I got your lighthouse vetical angle at 77.76 degrees. Good luck

Dennis


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## Sallen1215 (May 10, 2014)

Dennis i think i have my angles pretty good here are my dimensions but i could be wrong.... any help would be appreciated

Stephen


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## routergieck (Feb 11, 2013)

Looks close. I calculate the bevel angle at 14.93 so 15 will catch it . The end angle is 1.42 degrees but you will be much closer by measuring the top and bootom dimensions as you indicated. You should be able to glue this at one time with rubber bands if the fit is good . Have fun

Dennis


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## JFPNCM (Dec 13, 2009)

Sallen1215 said:


> I am working on a lighthouse project for a customer and up til now i have been using the normal design of 6 sides with 60 degree miters done with a table saw or a track saw, i want to streamline this process and i saw these bits, I also decided for more "realism" i should go with a 12 sided which would be a 15 degree cut on each "stave" so with that said here is a picture of what i am making and it is 12 sides starting at 4" at the base and ending up at 2 3/16" and the glue surfaces is driving me nuts. Any help would be appreciated.
> 
> Stephen Allen


You might also want to look at the Bird's-mouth bits from Lee Valley: Bird's-Mouth Joinery Bits™ - Lee Valley Tools

I have used these successfully on barrels and half round ends for planters but none with a "taper" Their detailed instructions (based on diameter, number of staves etc) do however cover tapers.

For the final glue up I lay all the pieces out on 2" painters tape, add the glue and then roll them around a circular frame (equal to the internal diameter and wrapped in wax paper so it doesn't stick) placed at each end. The painters tape holds the item until I can either band clamp it or if small enough use multiple heavy rubber bands. 

look forward to photos of the light house. 

Cheers
Jon


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## Sallen1215 (May 10, 2014)

John thanks for the help the birds mouth bit is the same thing is the multi-sided- glue joint bit it just operates under a different name. but if they have taper instructions i will have to give them a look, and Dennis the angles seems liek they will work but im trying to reduce how tight of a tolerance i have with the miters cause im using 3/4 birch ply so the more glue area the better

You guys rock

Stephen


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## Sallen1215 (May 10, 2014)

I looked at the lee Valley site and i couldn't find any documentation so i guess ill be making phone calls in the morning to the different router companies. I think the taper can be done just need to talk to them to verify what i might encounter as a problem.


Stephen


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## Cherryville Chuck (Sep 28, 2010)

Stephen, the taper of the staves controls the angle of the cone, it shouldn't be a factor in anything else. The angle between the segments remains the same.


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## JFPNCM (Dec 13, 2009)

Sallen1215 said:


> John thanks for the help the birds mouth bit is the same thing is the multi-sided- glue joint bit it just operates under a different name. but if they have taper instructions i will have to give them a look, and Dennis the angles seems liek they will work but im trying to reduce how tight of a tolerance i have with the miters cause im using 3/4 birch ply so the more glue area the better
> 
> You guys rock
> 
> Stephen


Stephen:

As soon as I hit send that similarity hit me. So it goes. If you can't find the instructions on Lee Valley let me know and I'll forward the set I have as a PDF.


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