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Scott C. Williams
12-18-2011, 9:38 PM
I build school house clocks using a cross cut sled with a jig and fixture to cut the eight sided clock face. I am considering the puchase of a miter saw to make this part. The saw I am looking at is the Bosch 5312 slider. For those familiar with this saw will it be accurate enough to cut the joints for the octagon clock face.

Joe Jensen
12-18-2011, 11:56 PM
I doubt any slider will be as accurate as your crosscut sled, but others may have a better experience.

Rick Fisher
12-19-2011, 1:45 AM
Hmm.. I have a Hitachi which is marginal.. I use it for miters but cut both sides without moving the saw.. otherwise they never end up right..

They are handy saws, but not really dialed in accurate..

Larry Edgerton
12-19-2011, 6:07 AM
Rick has the key to what you are doing. Set the saw as accurite as you can and cut both sides, if possible, without moving the saw. When you cut one face up and one face down from the same side of the saw any differences are cancelled out.

For example, and this is an extreme example, you need a 90 degree corner. You set the saw at 45 degrees, but it is actually cutting at 44. You make one cut face up which is 44 degrees, and then one cut face down which ends up being 46 degrees so the end result is a 90 degree corner.

You can't do this with everything because some profiles will not allow it but when you can it works.

Larry

john lampros
12-19-2011, 6:35 AM
There is too much play in the sliding arm to get accurate enough in all the sliding chop-saws I tested. So I went with a non sliding 14". Get the thickest and best blade possible. you might want to consider a guillotine cutter Like framers use (which are usually set up for 45's) but can be adjusted or modify a stop for the correct angle. Thats about the only thing thats going to be as accurate and possibly faster than shooting. I believe Lion makes a good one. I see grizzly has knocked one off as well but I know most of the framers in this city use the standard. the cuts are perfect laser strait and no tear out what so ever on any wood. You'll still need to "rough) cut them on a chop as the guillotine is just for the final cut and fitting.

Larry Edgerton
12-19-2011, 6:51 AM
I have an original Lion trimmer. The company is no longer in business, another victim of the knockoffs. They do a great job but it is a slow process and be aware that you are limited in the width of stock that you can miter.

For the kind of thing that you are doing I usually use one of my old Delta cast iron straight miter boxes, the one with the jackshaft that holds the blade. I consider them still to be the best reasonably priced chop box ever made. Once tuned they stay that way for a long time. I have four, so I'm set for life.:p

Larry

david brum
12-19-2011, 10:06 AM
I had high hopes for the accuracy of a pretty expensive Hitachi slider when I got it a few years back. I found that I had to do lots of trial cuts to get complex joints to fit just right and it wasn't repeatable. I eventually threw in the towel and made a version of this http://www.in-lineindustries.com/single_dubby.html which allowed me to make 12 1/4 degree cuts that came out perfectly. 22 1/2 degree cuts are a cinch. Rockler also has one http://www.rockler.com/product.cfm?page=18063&filter=sled.

Rick Gooden
12-19-2011, 10:56 AM
I have recently retired my miter saws for accurate angle cuts. I finally found the machine that allows for the type of accuracy that you are looking for, it's an old Millers Falls miter box with sharp Diston saw. It cuts quick and accurate and is an absolute pleasure to use, and the miters (4 sided, 5 sided, 6 sided, etc.) are all dead on. Cost for one in very good condition will be in the $3-450 range, but worth every penny.

Richard Wolf
12-19-2011, 5:39 PM
I agree with the Dubby, http://www.in-lineindustries.com/double_dubby.html. This guy has made a living out of his fixture which is designed to do exactly what you are doing. He is getting older and sometimes his customer service has been lacking, but his product is great,

paul cottingham
12-19-2011, 6:53 PM
I have recently retired my miter saws for accurate angle cuts. I finally found the machine that allows for the type of accuracy that you are looking for, it's an old Millers Falls miter box with sharp Diston saw. It cuts quick and accurate and is an absolute pleasure to use, and the miters (4 sided, 5 sided, 6 sided, etc.) are all dead on. Cost for one in very good condition will be in the $3-450 range, but worth every penny.
+1 on the mitre box. I have an old Stanley with a disston saw. My mitre saw is now on a shelf.

George Makra
10-21-2020, 2:43 AM
You could use a shooting board. It dosent take long to make a adjustable shoot board.

richard poitras
10-21-2020, 8:04 AM
Anyone have there own opions of the saws on the most accurate miter saws reviews list? As I am looking for a new saw and the Kapex is just out of the question do to the price. Its not going to have to be portable, but being accurate is the key to my search
.

Steve Rozmiarek
10-21-2020, 8:22 AM
Like everybody said, super precise repeatability of miters is hard. If you cut a master cut making it as wide as possible, then you that to check your settings by just looking at blade alignment against it, you will be good to go.

Some saws are better than others. My old Makita 1013 is great as long as you hit the mitre detents from the same direction every time. I've got another that is not as good.

glenn bradley
10-21-2020, 9:02 AM
I doubt any slider will be as accurate as your crosscut sled, but others may have a better experience.


I have read threads by people claiming adequate accuracy from a miter saw but, read far more that deny it. It could be a case of "the eye of the beholder". Skil to Festool, there seem to be more posts of inaccuracy than of accuracy. This could also be the typical negative reviews outweigh positive reviews scenario.

If you are used to a quality tablesaw and sled for joinery, a typical CMS is going to seem crude in my experience. I don't even have a CMS in the shop anymore; it lives out in the shed and comes out for trim work and construction stuff but, that's me.

John Gornall
10-21-2020, 10:02 AM
I have a shop where I've made my living for 40 years - part of our work is making wood parts - have cut and joined 500,000 various frames.

Miter saws are made for carpenters - designed to cut the biggest piece of wood the blade can cut - not precise. Put a 2x4 on the saw and drop the blade to contact the wood, not running - you will notice the first contact has the teeth cutting up through the wood not pushing it down against the table.

There are saws made for making frames - have a completely different geometry. The fence is outside at the outer edge of the blade - you pull the wood towards you against the fence - so the blade is always cutting down against the table - no wood movement. 2 blades fixed at the angle required. Look at CTD saws.

You can make a miter saw work. No sliders - hopeless. Get a basic chop saw. Move the work piece up from the table and out, towards you from the fence so the blade is always cutting down against the table. Put a 2x6 flat on the table and a 2x2 on that against the fence. All wood milled flat and square. Make cuts, test, adjust. Get 2 saws, these are cheap, leave them fixed left and right.

10 inch blade, not 12 inch unless you need 12 - less deflection

Thick kerf, negative rake, blade of 80 teeth not 100 or 120. Bigger carbides, more sharpenings, longer life. And the bigger carbides run cooler.

Try different blades - I like triple chip for hardwoods.

Christopher Giles
10-21-2020, 10:06 AM
I just purchased a Dewalt dws780 after an exhaustive search to replace my old Ridgid. I use it in my shop to do all of my 45's on cabinet door frames. I is dead on, right out of the box. Very impressive. One thing though, Do Not expect good results with the blade that comes with the saw. Put a proper crosscut blade on it, and it will not let you down. This is the most often used machine in my full time cabinetmaking business.

David Sochar
10-21-2020, 10:09 AM
I disposed of all my 'disposable' consumer type miter saws years ago. Bought a CTD steel and iron saw. Not a slider, so that inaccuracy is lost along with some capacity. But the accuracy for miters is excellent. Set it and hold it. One cut or a thousand.

Bosch, DeWalt, Hitachi, Makita, etc. They are all in that same class. Festool may be better. I will confess to having a nice old Bosch in the shop for the odd tall or wide cut s we may need to make. But it is stored under the bench, unplugged - a sure sign or infrequent use.

The CTD saw (similar to an Omga) is cast iron, Baldor motor, common pivot bearings, off the shelf switch....is engineered to last forever, with just two wear points.

But, if you are square cutting to length, a good sled will be better and faster. We just got a Hunter miter fence that has all sorts of great features. That may be all you need.

Robert Mayer
10-21-2020, 10:14 AM
Holy cow this thread is 9 years old you guys are commenting on.

With that said, inaccurate readings is why I no longer own a miter saw. I don't know why they cant make a decent saw that does not cost $1500.

Kyle Iwamoto
10-21-2020, 12:12 PM
Holy cow this thread is 9 years old you guys are commenting on.

With that said, inaccurate readings is why I no longer own a miter saw. I don't know why they cant make a decent saw that does not cost $1500.

Lol! I wonder if the OP had his question answered.

Steve Rozmiarek
10-21-2020, 3:09 PM
Holy cow this thread is 9 years old you guys are commenting on.

With that said, inaccurate readings is why I no longer own a miter saw. I don't know why they cant make a decent saw that does not cost $1500.

Lol, I completely missed that!

richard poitras
10-21-2020, 3:23 PM
I saw that the thread is old but it turned new again with updated questions..

Chris Padilla
10-22-2020, 12:26 AM
Sometimes old threads pop up now and then due to folks searching on particular topics. It is usually better to start a new topic.

Scott Winners
10-22-2020, 12:33 AM
I find with my sliding miter saw the faster I jam the blade through the cut, the lest precise the angle is. Thicker blade better. A sliding miter saw is not, in my experience, a precision instrument. Frame up an octaganal gazebo, sure. Eight sided clock face, not the right tool for the job.

John Gornall
10-22-2020, 10:14 AM
An excellent tool for miters is the Veritas Shooting Sander by Lee Valley - you can also make your own

Picture framers use a hand powered disc sander which is quite precise but expensive - AMP Disc Sander

Any shooting board or jig you make should have a 2 layer fence so to adjust it you can loosen screws and shim a little for accuracy -:I like playing cards for shims

If you are making a shaped profile moulding which can't be turned on it's back you will need both left hand and right hand shooting boards

Miters are fun!

John Gornall
10-22-2020, 10:19 AM
I recall seeing sandpaper glued to an old saw blade in a tabkesaw and miters sanded using miter gauge or a jig against the side of the blade