ok…so I bought this on myself…I’m making this mirror that is 2ft by 4ft and have miters that are about 12″ long at each corner. I feel so dumb asking this questions, but how do I cut the miters? the wood 4ft off of the table seems uncontrolable….how do I make this acurate?
The outside edges of the mirror are scrolled in wild and whacky curves, not a straight edge.
I did cut teh mitres before I cut the scrolls, but obviously they arent accurate. How do I recover?
Alison
Replies
Alison, If you make a 'sled' to fit into the miter guage slot, and attach to it a straight lenght of wood strip at precisely 45 degrees, you can handle awkward lengths of wood for mitering.
By adding a temporary 'Stopblock', you can make duplicate pieces to the exact length (2 at 2ft & 2 at 4 ft) The sled can be made of 1/4" plywood and the 'runner' of 3/8" x 3/4" wood strip. Sand and fit in table slot for smooth sliding fit. Try on scrap wood 'till you get a perfect fit then permantly nail the top strip to the sled (Glue if you like)
As far as the uneven outer edges are concerned, Keep the inner straight edges against the topstripwhen you 'clean up' the miters After you clean up one miter of one side or the frame, flip the side to cut the other miter, BUT keep the flat side to the top strip.
If after you assemble the now perfect mitered frame,you find the mirror is too wide for the altered dimentions, just re cut the 'Reveals' a bit more by using the tablesaw's fence and hang up your sled. Good sledding. Stein
Edited 9/27/2003 11:23:04 PM ET by steinmetz
Alison,
Two options come immediately to mind.
First is to shoot the corners straight by hand (sharp hand plane)
If you don't feel your hand plane skills are up to scratch, assemble the frame anyway with the gaps in the mitres. You may want to use hot melt glue and a bit of scrap MDF on the back of the frame to keep things in place. Run a saw cut through each mitre joint (tenon saw). The kerf is a constant width, so the two sides of the kerf will mate perfectly when the job is re-glued (assuming of course that the gaps are less than about 1mm).
Hope this helps - there are many other ways but these are the simplest in my opinion.
Cheers,
eddie
I would follow Eddie's suggestion with the saw kerf and if necessary , to keep the length needed for the mirror , glue a spline in the kerfs.
Recover? No problem!
Cause it sounds the simplest, I'm going to try Eddie's suggestion tomorrow. I had thought that if all else fails I could "spline" the gaps in the miters with black epoxy and use it as a decorative element, but routing out some scrolls in the surface...so it looks like I ment to do it (rolls eyes at self).
Alison
come back if you need more help. The technique that springs to my mind is to make yourself a mitre box and cut the mitres with a hand saw. Then clean up the joint with a block plane on a 45 deg shooting board.
Ian
I agree with Ian...
Why go to all that trouble making jigs when the basics work just as well.
I think we some times forget the simple things we were taught with all these fangle gadgets we use today.
Mike
mmmm....I'm glad things got so busy yesterday that I didn't get a chance to work on the frame...a mitre box would be pretty darn simple and simple is good. Today is the day...I'll let you know how it goes.
Alison
Alison,
I don't know if they make a mitre box in a 12" width. The cut you get using this is approximate and may need to be re-trimmed as previously discussed.
Good luck with whatever you decide.
eddie
They don't...tried my own knuckleheaded fix today...didn't work...don't even want to talk about it. Served penance by milling up 50bdft.
Another chapter will be forth coming
Alison, assuming you have a back saw and block plane, try this
mitre box 1) get a piece of 3/4 ply about 2-3 ft long and about 1 5/8 inches wider than your picture fame stock.2) mill it on the table saw so you have two long PARALLEL edges - this bit is very important.3) mark a line at right angles across this board 4) take two strips of 3/4 ply, each about the same length as the piece in step 1 and about 2 in wide, make sure one edge of each strip is straight and at right angles to the face of the ply5) stand each strip on its true edge and off-set the ends by about 12 inches. Now ensuring your mitre gauge is set to a true 45 deg, cut a kerf through both strips that is about 1/4 to 1/3 the height of the strip (watch that your fingers stay out of the balde !) 6) attach one strip to the board from step (1) so that one edge of the kerf is in line with the line marked at step (3) 7) now line the 2nd strip up on the other side of the board so that the off-set between the same side of the saw kerf is EXACTLY the same as the distance between the strips (three spacers all the same length makes this step easier). 8) you now have a 45 deg mitre box customised for your stock. to use clamp the box over one end of your board and using a back saw extend the kerfs all way to the base board cutting through your stock as you go.
shooting board 1) piece of 3/4 ply with one true edge2) piece of 3/4 ply with one true edge, cut at a true 45 deg to that edge3) line up the true edges, screw together and attach a 3in high backer along the true edges. 4) clamp the end cut in the mitre box so you can use the block plane to clean up the saw marks.
Ian
PS My appologies if this is too much like sucking eggs
Ian...thanks for working with me on this, and no, I don't think you're trying to teach me to suck eggs, I don't think I'll be a good woodwork until I've been at this for at least 20 years, maybe 30 :)
As frustrating as this is sometimes, I love it. It is facinating, evolving and lets me think, create and do all at the same time.
Alison
If the pieces are already scroll-cut, this might help.
rip some plywood/mdf or what ever to the overall width of each piece of the frame and srew it to the back of each piece of frame. This will enable you to cut true miters on a table saw(do you have one?)
Another way is to do the same as above but miter the back frame first. Then you can use a router to flush trim the frame parts for the mirror
There are many other ways to "skin the cat" Maybe one of these will help. If not, and you do have a table saw let me know and I have a few more tricks for you.
I do have a table saw....powermatic 66
and I really like that idea of using a back frame and flush trimming with a router. I am hopeful again. Optimistic even! I can get perfect miters on the mdf, and then voila, clamps, router and I'm good to go :)
Thank you that was a great suggestion.
Alison
Another trick... buy one of the "adjustable drafting triangles" from Office Depot, Staples or a drafting supply store. They are a clear plastic triangle that has a protractor on them. They make setting the angle on the blade or mitre guage a breeze and are EXTREMELY accurate. Talk about 101 uses
To all
Wish I coulda shared the victory boogie in the shop today. Nailed the mitres. Dead on. Looks great. Whew!!
Ended up using a multitude of techniques - making a guide, using a router. Making a miter box for the two end pieces....
I have photos will post before and after shortly.
Thank you all sooooo much for the advice and guidance. All of it helped me get my mind around this problem.
Ian, A MITRE BOX? HANDSAW? BLOCK PLANE? SHOOTING BOARD? What.ll they think of next?
This High Tech generation has gone TOO far! We older guys get along with T S's, R A's jointers, planers, BS's, Air nailers Belt sanders DP's and we're too old to learn to use your new fangled gimcracks.
Humph!! Shootin' planes, Miter boards, Are they battery operated? U L rated? OSHA approved? Come with instructions? Enviromently safe? This world is going to hell in a handbasket, (If you want MY 'pinion.) Stein.
Stein
If you want to get real cute, Bosch make (or did so up until about a year ago) a powered mitre saw, and with my electric plane I can shoot a mitre as fast as (and make as much mess as) you can with your belt sander !
Ian
Edited 10/2/2003 6:51:10 AM ET by ian
Let me add two techniques. The first has already been mentioned ... the sled. But what I have is a sled with two fences, so that I can cut miters accurately. I ensure that the fences are exactly at 90 degrees (with the apex farthest away from me, so that I put the boards to be cut on the outside of the fences and cut through them and into the fences). Cut one miter on one fence and the mating miter on the other fence. To make this slightly more "accurate", I have one of my fences slightly adjustable. If I put the object that needs a mitered board on the outside (in my case chessboards) between the fences and adjust the fences so that they represent the actual angle, and tighten them down, the miter fits exactly.
The second option would be to build a jig to hold the two pieces at exactly a 90 degree angle, with the pieces slightly closer than the dimention of the router bit you use to clean up both cut edges at the same time. Add a piece to the jig so that the router runs approximately through the pieces at the desired angle. As long as the router doesn't wobble, the cut surfaces will mate exactly. Don't take much off each surface. Note that this technique as well as the prior one would need some sort of stop block to ensure that opposite sides were exactly the same length.
John
Alison,
I think your problem with the fit of the miters, may be that wood this wide, depending on the species and how it was cut ( quarter sawn vs. flat sawn) will shrink and expand so much that the miters will really never stay tight. If the project were mine, I would get the miters to fit tightly, just by using a block plane, and then clamp them together an chisel butterfly dovetails into the back side, using at least two at each joint, with one as near the outside edge as possible. Then I would, as soon as possible apply a finish, that would exclude as much moisture as possible, something like varnish or polyurethane ( I have never before in my life recommend polyurethane ), coating all surfaces. While I can’t be sure this would keep the miter tight, it would certainly lessen the movement.
Rob Millard
Rmillard,
You've got a good suggestion in the use of butterflys. I use something similar, and would like your opinion as to its usefulness vis-a-vis butterflys. What I do with my chessboards, which have a border which is about 3 inches wide, is to cut a groove in the mitered edge into which I set a spline. I have the grain running perpendicular to the grain of the edge, for strength. The spline runs through the miter, so that when I rout the final edge you see this wood as part of the final edge. I've used the same woods, so that the spline isn't really noticable, and have used contrasting woods, so that the spline adds a nice detail.
Your comments as to how this compares, strength wise, vs. butterflys would interest me. Thanks in advance.
John
I have made mitered frames like you are describing , using the spline. With the narrow width involved ( 3”) I was sure that the expansion/contraction issue will be solved with just the spline. I would only resort to the butterfly dovetails, for something in the 6 inch or wider range.
Rob Millard
Good advice from Rob, Alison.
I recently had a student build something similar and we used two rows of 60mm dowels, spaced 30mm apart along the whole mitre width for the same reason. Butterflies would also tie the job together
The handsaw trick is the one that turners use when making blanks, and is the easiest for novices to get working well - As I said, you could shoot the mitre by plane if your skills are up to it.
Let us know how it worked,
eddie
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