Template help?

[Kirk (KC) Constable]

I've just started a rather large (is 28' long large enough?!?) boat-shaped mesquite conference table. The base will also be boat shaped...and after studying on it for some time, I've got that part figured out.

The top will be seven 48" wide panels with grain running the width of the table, and with a 3" border all around. I'll be using templates and a flush trim bit to cut the boat profile on the panels. That's no biggie...but it occurred to me this afternoon that I'm not sure how to cut the inside arc that needs to be on the border. It needs to be pretty much right the first time.

All along my thought was to simply turn the outie arc tenplate over and use it to cut the innie...but I guess that won't work. Can I lay the outie template down on another sheet of MDF and simply cut through the MDF using a straight bit and a template bushing guide? Is there an easier way?

Thank you. I hate it when I have things all figgered out and then realize it won't work after all! :(

KC

[Mark Duksta]

Here's a thought:

Make the inner template with a removable spacer in the middle. The spacer would equal the combined thinkness of the guide bushing on opposing sides. After you use the template to cut the inner, remove the spacer(s), and then use the same template to cut the inner curve.

Mark D.

[Ken Wright]

glad you got that job .... looking forward to seeing that table ... wow .. a biggie ..

shame you can't ask david marks .... he makes an mdf template for everything he does ... you might try that on his site ....

[Jason Roehl]

Can you cut the innie and outie pieces close with the template and a jigsaw, then use a router with the template and trim both the innie and outie at the same time? Should be a perfect fit, then.

[Mac McAtee]

You will need to make a template to make the timplate. Make a template that is for the inside shape, make it 1/2" smaller than what you want the outside shape to be. Use it with a 1/2" router bit with a 1/2" guide bearing on it to cut a templet for the outside shape. (Or a 1/4" bit, 1/4" bearing or 3/8" bit, 3/8" bearing combo.)

Then take the original template and a router bit with a guide bearing that has a 1/2" (Change this dimension to match what ever bit you used to make the outside shape.) oversize guide bearing on it. For example a 1/4" bit with a 3/4" OD bearing. Cut another inside template using that combination. Your inside template will now be an exact shape to your outside template. Fit the two templates together and put a light behind them, look for small iregularities and sand or fill with something like masking tape until you get as much of the light cut off as you think you can. Then use your templates to make your table.


PS. There is something wrong with the math above, but you get the picture. (I hope) (;-}

[Steve Jenkins]

KC if you aren't going to save your main table template you can cut it down to start the process of making the edgband template. After cutting out the table I usually take the template I just used and reduce it by 1/2"all the way around. I do this by using either a rabbeting bit or a slotting cutter whichever I can get a 1/2" rab out of. after I rab the edge I will use a flush trim and go around to clean up the edge. Now I have a template that is reduced by 1/2" all the way around. If your template material is thin enough to rout all the way through in one pass lay your reduced one on top of the piece you are going to use for your edgeband. I screw both pieces to the bench top so neither can move. with a 1/2" flush trim bit rout around your reduced template and through the new one. You now have a female template that is 1/2" larger than your reduced one and the same size as your top. easy as pie and clear as mud right? Steve

[Kirk (KC) Constable]

Thanks for the replies.

What I did (which worked quite well, BTW) was cut the outer arc and sand the edge smooth. Then I screwed some scrap MDF to the work table and screwed the outer piece I just cut down to that, elevating it but leaving the area under the edge clear. Then I screwed the offcut piece down flat on the table and maybe 3/8" away from the outer template. Put a long 1/2" straight bit in the router with a guide bushing and using the outer arc template as a guide, took several shallow cuts until I cut through the inner arc piece. Matches up perfectly.

KC

[Joe Tonich]

Thanks for the replies.

What I did (which worked quite well, BTW) was cut the outer arc and sand the edge smooth. Then I screwed some scrap MDF to the work table and screwed the outer piece I just cut down to that, elevating it but leaving the area under the edge clear. Then I screwed the offcut piece down flat on the table and maybe 3/8" away from the outer template. Put a long 1/2" straight bit in the router with a guide bushing and using the outer arc template as a guide, took several shallow cuts until I cut through the inner arc piece. Matches up perfectly.

KC

KC,

I hate to ask, but, do you have any pic's of the process? Maybe I'm "brain-dead" today but for the life of me I can't pic in my head what your talking about :confused:

Joe

[Kirk (KC) Constable]

I guess it's hard to explain in words. I just re-read it and I can't understand it myself. :(

Yes, I do have some pics...but they're at the front of the roll I'm shooting as I build the table. I'll post them next month, or sooner if Grandma goes crazy taking baby pictures.

KC

[Steve Jenkins]

KC that will work ok with a large radius like your table but if you are doing sonething with a tighter radius the fact that you are adding 1/2" to the radius will cause it to not fit tightly. Steve

[Joe Tonich]

I guess it's hard to explain in words. I just re-read it and I can't understand it myself. :(

Yes, I do have some pics...but they're at the front of the roll I'm shooting as I build the table. I'll post them next month, or sooner if Grandma goes crazy taking baby pictures.

KC

Thanks. Looking forward to seeing them.

Joe