Replies

1. 
   edcross1 | Mar 03, 2003 05:10am | #1

   Mr Micro,

   this pyrely my opinion and only my opinion, last year I had a very simular project for a friend of mine. THe tool I used was my faithful Elu router. The reason I used the router was that I could create a template which made the batch process very easy. Boring I havr to say but very easy. I also had a cutter long enough.

   hope this helps for what its worth

   Ed

2. 
   Sprucegum | Mar 03, 2003 06:23am | #2

   If you can't do the router thing I would suggest the bandsaw.

   You can drill the hole first and use that as the pivot point on a jig to do your radius cut. Know what I mean?

   It's not what you chew, it's how you chew it
1. 
   UncleDunc | Mar 03, 2003 06:39am | #3

   If I read the print correctly, the hole isn't concentric with the radius.

1. 
   MHargrove | Mar 03, 2003 07:50am | #4

   But maybe his drill press has enough weird runout to make up for that.

2. 
   Sprucegum | Mar 04, 2003 02:34am | #17

   I"m embarrased! At first glance I thought the 6" radius point fell within the 2" hole area but no, of course not so then we jump to plan B:

   Make a jig for the jigsaw to cut the radius, unless you really want to buy more router bits<g>.

   I would drill the hole after to ensure the radius is always on the right side of the rafterIt's not what you chew, it's how you chew it

1. 
   Boxduh | Mar 04, 2003 03:04am | #19

   Please describe the jig or setup for the jigsaw to cut the radius off the corner.

1. 
   Sprucegum | Mar 04, 2003 07:25am | #22

   Use 9" wide stock x 1/2" or so thick, and 18" or even longer if you like.

   Mark the 6" radius on one end minus the distance from your blade to the edge of the jigsaw shoe. For example if your shoe is 1" from the blade to the edge you would only need a 5" radius. Pay attention to which side of the saw will be pressed against the jig, the blades are seldom in the center.

   On the long side of your jig fasten(glue&screw) a 1x2 that protrudes the distance of your shoe width. You may want to screw a small angle bracket on the end to act as a stopper.

   Now you can slap this on the end of your 2x8, hold down with one hand and zip around the corner with the jigsaw in your other hand - 83 more and done.

   Sorry I don"t know how to draw on the computer, its even simpler than it sounds. If you need more info please ask.It's not what you chew, it's how you chew it

2. 
   Boxduh | Mar 04, 2003 04:28pm | #23

   Thanks for your input re the jigsaw template.  I did not quite understand it, especially the stop with the angle part, but here is what I have come up with, after reading your post and thinking this through.  See the attached.  The template is 1/2" apple-ply (blue) and has a cleat attached (brown X) for registering against the 2x8 stock when clamping.  The Dewalt DW721K jigsaw (shoe and blade shown in red) is positioned ready for the cut, and the shoe edge will track around the edge of the template.  Since the cut begins as pure crosscut the blade should stay fairly perpendicular, as it comes around and out the tangent side.  I'll clean up with a belt sander clamped to a sawhorse, and bore the holes afterward with a stop, using a spur bit and my drill press. 

   
3. 
   DP | Mar 03, 2003 09:21am | #5

   how many do you have to make?

   is the hole centered with the radius on the part made with the same center?

   dp

1. 
   Boxduh | Mar 03, 2003 02:34pm | #6

   I need to make 84 of them.  The hole is not concentric with the radius cut.  I have a 3hp Freud router, and thought of doing the outside cut with a pattern bit, but with the 2x8 stock thickness, I will need a bit with a cutter length of 1-5/8" or more.  Where does one get a bit like that?  Jesada only goes to 1-1/2".

1. 
   AlanTurner | Mar 03, 2003 02:54pm | #7

   I had that problem also, with thicker wood - 1 3/4".  Use a pattern bit with top bearing and cut it as deep as you like.  Then, flip it over and use a bottom bearing bit, riding on the already cut radius.  MLCS, in its Katana line, as both bits with good length.

2. 
   ian | Mar 03, 2003 03:08pm | #9

   drill the hole first - use a drill press, and back up the hole to control tear out.

   make a template with a dowell that fits the hole - makes locating the template easier.   Route the curve using a template guide and a solid carbide spiral bit (up or down cut) - CMT make a 1/2in spiral bit with a 2in cut (I'd go for the downcut version to keep the chips out of your face) - the bit should cost you about 50 cents per rafter.

3. 
   DP | Mar 04, 2003 05:40am | #20

   Its a rafter, save your router for some real precision(unless you want to do that double cut process and change bearings).  Plus the amount of end grain break out your going to get doing that single cut in rafter-wood will really surprize you... and perhaps not in a nice way. Personally, I would use a band saw with a template then touch them on the edge sander to clean them up.  Set up your belt sander in a vise if you don't have access to an edge sander.  As someone else suggested, set up your drill press with a stop for the holes but I would do it after the round cut.  (remember not to cut your material to finish length until  you have executed the round)   Drill the hole after you have done the round.  Backing it with a piece of harder material, would help the tearout but use a sharp bit either way(and clamp the piece down).  A forstner bit or a hole saw should work.  A plunge router would be quite dramatic.  What are the rafters going into? dp  ps. I'm new to the forum, but not to wood.  blessings.

4. 
   eddiefromaustralia | Mar 03, 2003 03:06pm | #8

   Either the above approach or make a template and use a guide template on the router, as opposed to a pilot guided template bit.

   You can just use any suitably sized straight bit then, providing that the diameter of the bit is matched to the template.

   If you wish, you can also make the hole on the same template and drill the hole by plunging with the router.

   Food for thought,

   eddie

   
   

   ---

   Edited 3/3/2003 7:08:39 AM ET by eddie (aust)

1. 
   ian | Mar 03, 2003 03:09pm | #10

   hi !

1. 
   eddiefromaustralia | Mar 03, 2003 03:15pm | #11

   Hi Ian,

   Hope that things are fine at your place  - Noticed on the rafter drawing that these holes are 2" diameter, so I suppose predrilling and pinning the template through the drill hole (or screw the template onto the rafter direct to subsequently mark the centre of the hole) is an option, but I'd personally still go for the template approach with the router bit - I'd also locate the template with a couple of side rails where you don't need to cut and g-clamp the side rail to the body of the rafter.

   Trust that things have quietened down somewhat with your work.

   I'll give you a call tomorrow.

   Cheers,

   eddie

1. 
   ian | Mar 03, 2003 03:27pm | #12

   I'm thinking a 2in saw tooth forstner or speed bore - it's a rafter so minor breakout arround the hole shouldn't be an issue.

   side rails top and bottom with a 2in dowell through the hole - you wouldn't need clamps at all.

   I'd do the hole first as this detail defines the end of the rafter and could be set up by eye.  I'm assuming that because it's a decorative rafter, the inboard end overlaps the real rafters and is hidden - so the actual length of each rafter can vary.  If not then I'd still use the hole as the reference length - you just need to measure it's location.

   work is still hectic - but I've now got some help.  How are the students progressing with their boxes?

   take care

   Ian

5. 
   zacko | Mar 03, 2003 04:47pm | #13

   Hi, I've been a longtime lurker and have decided to jump into the game. I couldn't help but notice that the dimension from the side of the piece to the center of the 2" hole is 3 1/2" and the opposing radius is 6". Wouldn't this add up to 9 1/2" wide instead of the 8" width that is specified? Sorry this doesn't answer your question but its just an observation.

1. 
   jako17 | Mar 03, 2003 05:49pm | #14

   Welcome zacko, where on the drawing does it show that the centre  of the 2" hole and the 6" radii are the same point or have I missed something?

1. 
   zacko | Mar 03, 2003 07:38pm | #15

   Thanks for the welcome. In response, no you are not mistaken. The 2" bore and the 6" radius do not share the same center point, I stand corrected.

6. 
   Arcticat1 | Mar 04, 2003 02:15am | #16

   Definately template and router. Jesada has a super-duty 3degree downshear flush trim that is 2" cutter length, 3/4" cutter diameter. It has a bottom bearing. I take 3/4 od X 1/2 id bearings and put two onto the top of the shaft and keep it in a dedicated router so I can do pattern routing with template on top or bottom, whichever is better for the particular job.

7. 
   johnhardy | Mar 04, 2003 02:37am | #18

   I'd drill the holes on a drill press, using a stop to ensure uniformity.

   I'd then make a jig for the router to use (other posts have said to use a router with a bearing bit and then flip the piece to finish up using a bottom bearing bit ... very good advice.

   Before using the router I'd use the jig to mark the line and then I'd take off the excess with the bandsaw, leaving about 1/8th of an inch for the router to cut off. The result will be less work for the router and a nicer finish cut.

   John

8. 
   finebuilder | Mar 04, 2003 06:55am | #21

   Quick question; What type of wood are you using?

                                             Miami

9. 
   eddiefromaustralia | Mar 05, 2003 03:03pm | #24

   Mr Micro,

   How-to cut circles with a jigsaw - these pics saved me drawing them up.

   Cheers,

   eddie