Hello all,
I am about to make some picture frames and was wondering the best method for mitering the corners. I have a nice power miter saw and usually use it for cutting angles. I notice in many articles that a sled is built for the table saw with a runner in the miter track. It always seems like it would be more difficult to get good results with a heavy sled and dealing with the slop in the bar. I am also hoping to avoid fiddling with shooting boards and planes. What methods work for everyone else?
John
Replies
make yourself a nice sled for the table saw, I have several for all kinds of things. as for miters its hard to beet the table saw with a sled. good luck.
i use a sled everyday, my mitersaw is usually in the work truck
John,
In woodworking, as in most other things in life, there is no ONE way to do anything. Either a miter saw or a well-made sled will do equally well for cutting the miters for picture frames. Professional picture frame stores utilize specialized miter saws and have been doing so long before the common "chop saw" miter saw became so popular. All that matters is the care with which you set up either machine and that your technique is careful when positioning and firmly holding or locking down the frame pieces.
In the countless threads here about table saw sleds and methods of eliminating slop between the runners and the slots, the emphasis is always on exactly fitting the runners to the width of the slots, using exotic materials such as UHMW plastics, metal runners, etc.
I believe we get into a mind-set about the way a runner should fit the slots due to the use of a miter gauge which uses only one slot. Its runner must accurately mate with BOTH sides of the slot with no slop. We erroneously extend that thinking when we contemplate using both slots. With the miter gauge, the width of the slot (and the length of the runner) is the "base" provided to resist lateral movement or twisting. But that is NOT the case when we use both slots. Then, the distance between the slots provides a vastly increased base.
Anyone who's used a single-slot miter gauge knows that it's very hard not to experience some slop and that even after going through all the methods of removing it, the problem seems to return and "technique" always involves putting pressure on the gauge so that it stays pressed against one side of the slot, rather than rely on its staying true as result of its side-to-side fit in the slot.
Even in metal work, with all the precision possible in that material, it is extremely difficult, requiring very high precision to make 4 surfaces align to the precision needed to prevent the movement we want to avoid in a sled. It is impossible to do using wood as the construction. Fortunately there is a better way to do it.
Contrary to the advice in almost every other sled construction project you can find, the sled's runners need to be MORE NARROW than the slots and fitted so that they contact only 2 surfaces - the INNER WALLS of the slots. Bingo - perfect registration, no slop (ever). No worry about the runner's changing dimension and binding in the slots with changes in the shop's humidity. Just make them 1/8-1/4" thinner than the slots and let them expand and contract as they wish in that space as they stay in contact with the slot's inner wall.
There is an article in Taunton's publication "Tablesaw Methods of Work" edited by Jim Richey on page 146 that describes the construction of such a sled. The article describes a sled with a 1/2" thick acrylic base and ball bearings instead of wooden runners. It could be made that way (great idea, those bearings) or with an MDF base and wooden runners. The materials aren't important, just the concept and the method of fitting the sled to the slots during the attachment of the front and rear fences. It's one of those slapping oneself on the forehead - why didn't I think of this before - type of experiences.
If you can't get the book I can describe the general design and construction if you want.
Rich
I have a 12 SCMS that is very accurate but.. due to the tendency of the stock "walking the fence" (moving slightly from the up-cut design of the miter or SCMS) you can end up with a slight gap if you do not have the stock secured well. So.. if you want very tight miters as you need with picture frames and small boxes.. go the sled route IMO.
Sarge..
Woodworkers' Guild of Georgia
It's fairly easy to make miter bars fit the slots without any slop. If your saw is properly tuned and you know how to make an accurate sled, I think it is a great way to cut miters. For years, I made my sleds with all different types of materials for the runners, I prefer two. Now I use the Incra slides, best money I've spent.
My daughter is a professional framer. They use a simple Makita chop saw as do many frame shops. Her shop has many specialty machines for attaching the miters, doing metal frames, inserting chevrons, clinch nails, etc. It's not how you cut the miters but how accurately and how precisely the opposite sides are to length. Any secondary operation, such as shooting, can change the length. Minute differences in length effect the fit of the miters.
Beat it to fit / Paint it to match
I agree with the Incra Miter gauge. I miter 4" wide stock and am getting a consistent squeeze with the Incra. The 1000SE is a good one and if you look around you can buy one for a little over a 100.00. The blade I use for cutting my miters is a CMT thin kerf 60 tooth blade. You get the best results with the blade raised all the way up. That prevents the back of the blade from rubbing the cut an possibly burning the miter. If you really want a slider you can now buy the same slider used on there miter gauges from them.
I don't use the Incra miter gauge, John. I still use my old Rockwell miter head that came with the saw. I made it fit the slots by peening to enlarge and filing for a fine fit so there isn't any slop.I use the aluminum slides made by Incra for sleds and other jigs that run in the miter slots. They make them in a couple of lengths, I have several. These slides can be adjusted to perfectly fit standard 3/8" x 3/4" miter slots. When you mount them to a sled, you drill some access holes to get to the adjusters, just in case you need to tweak them in the future. I think they sell for $20.It's important that your saw is tuned when using a sled. I prefer a full bodied crosscut blade, I find the thin kerfs wobble ever so slightly. The full bodied professional blades have larger carbide and can take many sharpenings. If everything is tuned well, the back of the blade should not touch the cut. If you get a little blade drag, either the work is moving, the blade is not in line with the miter slot or the blade is wobbling. Having to raise the blade is often a sign the blade is under stress for the job at hand. This can add a safety concern if the blade isn't guarded.Beat it to fit / Paint it to match
The saw blade I use for my miters is a CMT 205.060.10 with a kerf of .102. There is no wobble! That blade has cut over 120 miters on 4" stock and am getting a perfect squeeze every time. The reason I have the blade all the way up is to keep the back teeth from burning the cut. You can adjust your saw all you want and I doubt you can overcome that. Yes, it is dangerous, you just have to keep that in mind and know where your hands are and the blade. I have run a lot of very dangerous machines for over 55 years and still can count to ten, can you?
I agree with the comments that there is no single "best" way to cut and miter frames. I've used both my TS and my chop saw, as well as an old foot-operated guillotine-style miter machine from a frame shop at which my Mom worked decades ago. For softer woods, the latter is probably the most accurate, but not everyone has access to one.
For TS or chop saw use, non-slip surfaces on the fence and a quick clamping method helps to increase accuracy for me. But, I still use a well-tuned shooting board to achieve precise angles and precise corresponding lengths for the frame members.
One further bit of information.
I often have trouble cutting the miters on a sled if I feed the piece so that the acute angle (the outer corner) is the leading part into the blade. The corner tip sometimes breaks off. Not only is it an annoyance and ruins the piece if this is the second cut to not only miter but to bring the piece to length, but it comes flying off the frame member like a shot and really stings if it hits me. I wear goggles and have worn shop gloves after it became a very frequent problem with some maple stock. Feeding very slowly improves but does not always prevent the problem.
I've put a plastic guard on the sled that covers the end of the piece right up to the blade and deflects these missiles but it's startling when it happens. Not at all a pleasant consequence of cutting miters.
If I feed so that the obtuse angle (inner corner) enters the blade first the problem seldom happens. Seldom, but occasionally. The corner tip is fragile, especially if the grain pattern there is not straight and almost perfectly in line with the long axis of the piece.
I've never had this happen using a chop saw.
Rich
chiseler3
I am a hobbyist who makes a couple of frames a month. If you are doing a large number at once, it may be worth the time to set up the t-saw and sled (and I do have one). Miter saw is much better for this purpose if you are doing one frame at a time. T-saw is like using a brush hog to mow your lawn.
I have a 12" SCMS and a sled for my table saw, either one will work well, but for small pieces I like the sled better I feel safer using it.
Mike
John,
I made a sled for my tablesaw and it is as accurate as you make it. I used a 45 degree drafting triangle for the construction of the sled and checked it with an accurate square before securing the pieces to the base. I also used quartersawn hardwood for the sled runners and have not had any problems with frames not being square.
Greg
For dead-on accuracy, get one of these from Rockler:
http://www.rockler.com/gallery.cfm?Offerings_ID=6533&TabSelect=Details
They're pricey, but if you have a lot of frames to make, your miters will be tight-fitting with NO tearout. It's a professional frame shop tool.
John,
My advice is completely different from anything you have gotten so far. An easy way to make great mitered frames is to use a handsaw on a homemade miter box, followed by tweaking it with a plane on a shooting board.
To learn more about shooting boards, and even miter boxes, look at the homepage for fine woodworking. There are a number of good articles about all of this. It is not difficult and it is MUCH more precise than machine work.
But anything can work when you learn how to make it work. Have fun choosing and learning. If you have any questions on shooting boards, let me know.
Mel
Measure your output in smiles per board foot.
I agree with MelI've been shooting mitres in all sorts of material, from veneer to construction-size boards, for more than 20 years ... and although my machine of choice is my trusty Makita LS 1013, if I want perfection I set up a shooting board and sharpen my Record No 8, and cut by hand.Malcolm
http://www.macpherson.co.nzEdited 8/22/2009 8:27 am ET by Malcolm
Edited 8/22/2009 8:27 am ET by Malcolm
Picture frames.. You did not state how many or how often.
For the price.. The Nobex Pro Master Miter Saw is hard to beat for the application. Blades work well and reasonably priced.
Both will work as the posts here can attest. A different approach is to use a stationary disc sander. A guide to hold the work at whatever angle in relation to the disc is all you need. We do this all the time for smaller mouldings. Hard to beat the quality of the joint when done this way.
-Paul
I constructed the tablesaw sled featured in Fine Woodworking a few years back. I have made a dozen frames with it so far and every one has been absolutely perfect and cutting the miters takes so little effort.As has been mentioned, the key is to make sure the opposite sides are EXACTLY the same length. This sled guarantees that. Another aspect of the jig that aids in accuracy is that one miter is cut on one side of the sled, while the other miter is cut on the other side. Since the sled is constructed such that the left-side and right-side fences are 90 degrees, the results are always dead-on.
precision table saw sled...
i finally found another pair of ball bearings. the plexiglass arrived two weks ago. apparently i exhausted the supply of three different hardware stores. construction will begin very soon! great idea.
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