Reducing Tear-out

Steve Campbell

Grumbler in Training
Joined
Dec 6, 2017
Posts
6
Location
San Antonio
Hello all,
New to the forum here, looking for some advice or ideas on tearout reduction.
We are currently using a Universal Machinery double mitre cutting system and are seeing a significant amount of tear out on most frame mouldings. We primarily use Arquati and Larson Juhl moulding.

Any help is appreciated.

Thank you
 
I'm not familiar with that particular machine.
The usual advise for reducing tear out is replace or sharpen the blades, and replace the chip breakers.
 
If by tear out you mean chipping, then I would say you have dull blades, wrong blades, or blades that weren't sharpened properly. Check with W.E.Quinn Saw Co., Joe 314-869-5353, for possible corrections
 
The saw is only a few months old so i would hope that it woulding be a dullness issue but we do cut a significant amount of moulding on it. I'm not familiar with " chip breakers" can you explain a little what you mean by that?

Thanks Y'all
 
So, you didn't sharpen the blades for a few month?
 
breaker goes between the blades

cb8.jpg
 
The saw is only a few months old so i would hope that it woulding be a dullness issue but we do cut a significant amount of moulding on it. I'm not familiar with " chip breakers" can you explain a little what you mean by that?

Thanks Y'all

Well, your blades will get dull and that could easily be the problem. Of course, many things affect wear, such as the number of frames you cut, thickness of the mouldings, the amount of hardwood vs. softwood, the amount of gesso on the frames, etc. I send mine for sharpening about every 3 weeks, so if you are cutting a lot of moulding, that's probably your issue. A good rule of thumb in my shop is around 120-200 frames is what I expect to cut from a set of blades before I need to sharpen them. I also use cheap black mouldings to help me judge this; when the cheap black mouldings start chipping too much, the blades are dull.

Don't throw them away. Send them to a sharpening company. You can often have blade sharpened 12-20 times before they are worn out. Quinn Saw and Ultramitre are 2 good sharpening companies.

Some saws can take chip breakers, which help reduce chipping due to fallout from the pieces being cut off. However I have a Brevetti and can't use one myself. Not all saws are made to use them.

John
 
Correct, The blades have not been sharpened as of yet. The saw is new to us and we were unsure how often the sharpening should be done. We do anywhere between 50-80 frames per week mixed between hard, soft, and poly. We have a local sharpener right next to us but will need to acquire a second set of blades to use while these are being sharpened.
After inspecting the saw closer, it does not have a chip breaker nor a place to install one. It has an aluminum guide that the blades fall into during operation.

Any particular blades you can all recommend?

Thanks Y'all
 
Quinn Saw and Ultramitre both sell good, quality blades. That's all I buy. They can make recommendations to you based on your machine.
Others here are happy using blades bought at Lowes or HD or various online sellers.

Be cautious with the local sharpener. They may be excellent, or they may ruin your blades after only a couple of sharpenings. I used a moulding vendor for sharpenings when I first bought my shop, but found the blades were dull again after about 3 days use. I'm not doing that again.
 
Good advice, I know the other large framers in town also use this sharpener as well as our local hockey rink for the zamboni blades. We currently have ultramitre blades on there so I will source a second set and have these sharpened. Thanks so much for the help.
 
I guess it depends on quality of saw and blades to how long before changing and the type of blade?
I will ask the saw operator to count how many frames before changing of blades is needed bout I am going to guess it's well into the 1000s, we cut a wide range of moulding from ash, oak, and heavy gesso to soft itallian obeach mouldings (no poly) we have a aging casses 939 the blades are 90 tooth Atkinson Walker blades tripple chip, I agree with the local sharpener advice ours go back to Atkinson Walker we have eight sets (16 blades).
 
I posted this on another thread recently but, Quinn Saw.:cool:
The blade quality and the company doing the sharpening can be more important than the saw that you use.
Your local blade sharpener can actually ruin your blade.
They might be OK for sharpening lawn mower blades, rough contractor blades and scissors, but for precision clean cuts on picture framing moulding without vibration, I recommend Quinn , as others have, for new blades and sharpening.
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Good advice, I know the other large framers in town also use this sharpener as well as our local hockey rink for the zamboni blades. We currently have ultramitre blades on there so I will source a second set and have these sharpened. Thanks so much for the help.

I know nothing about the sharpener you are speaking about, they may be the best in the business. I just want to tell a little story about a sharpener that everybody else uses in my area. I use both a Frame Square Saw and Morso Chopper. Everybody was telling me how good this certain sharpener, no names of course, was so I decided to use them. I got 3 sets of knives for the Morso sharpened and 2 saw blades, supposedly straighten, balanced, & carbide tips as needed replaced. The knives came back blue from overheating and there were several carbide tips that flew off the first time I used the newly sharpened blade and there was a vibration that I did not have before the sharpening. So what I am saying is that I take recommendations about local companies, that normally don't work with the framing industry, with a grain of salt. I have researched companies that other framers nationally have stated as being good and I have not been a bit disappointed. I now used and will stick with the companies I researched because of the quality, customer service, and proficiency of their products. I recommend that you do the same research because it can make the difference between you putting out a good product or a mediocre product.

Cutting frames for picture framing need sharp blades and knives for both the saw and chopper. Because of the hardwood in many mouldings & the amount of Gesso on the moulding the blades will dull and need to be sharpened quicker than one would expect. For frame moulding there are certain things that have to be taken into account when doing the sharpening. The home building and cabinet making trade doesn't work with the same types of products that we work with on a normal basis so they can grab a saw blade off the rack and it works for them. You can be a good sharpener for the home building trade but sharpening and balancing blades or knives for the picture framing trade is totally different - that good sharpener for the building industry can go from being excellent in their field to a complete disaster for the picture framing trade. Personally, I recommend that you speak to the companies that are getting good comments on the Grumble - believe me, we are generally fussy about the vendors we use but we need to be, customers do not like open mitres, chipped corners, or sloppy cuts. I recommend checking out Quinn Saw and Ultramitre, it may save you from some future headaches and Tech Mark for chopper knives. just my $0.02 Joe
 
[QUOTE="Joe B, post: 1046187, member: 6402") believe me, we are generally fussy about the vendors we use but we need to be, customers do not like open mitres, chipped corners, or sloppy cuts. I recommend checking out Quinn Saw and Ultramitre, it may save you from some future headaches and Tech Mark for chopper knives. just my $0.02 Joe[/QUOTE]

Your $0.02 is worth a lot more than $0.02.
I couldn't agree more.;)
 
I meant to say "and try Tech Mark for chopper knives"
Ha!:p
Hey, I know what you were saying, Joe.;)
I have been a major supporter of Tech Mark for many years.
Jill at Tech Mark has been very helpful for a long time.
http://www.tech-mark.com
 
Joe brings up a good point about vibration, you want that as low as possible, even making sure your machine is on a solid base will make a difference, and don't start cutting until the blades are up to full speed, that seems like common sense but I have see people press the start button and just start cutting before the blades got up to speed.
 
I know nothing about the sharpener you are speaking about, they may be the best in the business. I just want to tell a little story about a sharpener that everybody else uses in my area. I use both a Frame Square Saw and Morso Chopper. Everybody was telling me how good this certain sharpener, no names of course, was so I decided to use them. I got 3 sets of knives for the Morso sharpened and 2 saw blades, supposedly straighten, balanced, & carbide tips as needed replaced. The knives came back blue from overheating and there were several carbide tips that flew off the first time I used the newly sharpened blade and there was a vibration that I did not have before the sharpening. So what I am saying is that I take recommendations about local companies, that normally don't work with the framing industry, with a grain of salt. I have researched companies that other framers nationally have stated as being good and I have not been a bit disappointed. I now used and will stick with the companies I researched because of the quality, customer service, and proficiency of their products. I recommend that you do the same research because it can make the difference between you putting out a good product or a mediocre product.

Cutting frames for picture framing need sharp blades and knives for both the saw and chopper. Because of the hardwood in many mouldings & the amount of Gesso on the moulding the blades will dull and need to be sharpened quicker than one would expect. For frame moulding there are certain things that have to be taken into account when doing the sharpening. The home building and cabinet making trade doesn't work with the same types of products that we work with on a normal basis so they can grab a saw blade off the rack and it works for them. You can be a good sharpener for the home building trade but sharpening and balancing blades or knives for the picture framing trade is totally different - that good sharpener for the building industry can go from being excellent in their field to a complete disaster for the picture framing trade. Personally, I recommend that you speak to the companies that are getting good comments on the Grumble - believe me, we are generally fussy about the vendors we use but we need to be, customers do not like open mitres, chipped corners, or sloppy cuts. I recommend checking out Quinn Saw and Ultramitre, it may save you from some future headaches and Tech Mark for chopper knives. just my $0.02 Joe



By chopper, i'm assuming you are reffereing to a guillotine style chopper to correct any off angles from the saw. We have one of these and it tears up to Gesso something awful. Now, maybe we have a bad brand as when we purchased it, we were just getting started and knew next to nothing and it is now collecting dust on the shelf. Is there a brand you reccomend?
 
Steve, I have the same saw you mentioned and the older models do not come with a chip breaker. That is a block of wood that supports the bottom back side of the moulding to minimize the chance for chipping. FWIW, the new models I believe have a chip breaker. I had a friend that is a machinist come look at my saw and draw up a little schematic of how he could make a steel frame that would hold a wood block creating a custom chip breaker. I have not followed up on getting with him to build it but you have reminded me to do so with your post. We have eight sets of blades that we rotate out for sharpening and we cut 75-100 frames a week.
 
Steve, I have the same saw you mentioned and the older models do not come with a chip breaker. That is a block of wood that supports the bottom back side of the moulding to minimize the chance for chipping. FWIW, the new models I believe have a chip breaker. I had a friend that is a machinist come look at my saw and draw up a little schematic of how he could make a steel frame that would hold a wood block creating a custom chip breaker. I have not followed up on getting with him to build it but you have reminded me to do so with your post. We have eight sets of blades that we rotate out for sharpening and we cut 75-100 frames a week.


Thanks Mike, It's unfortunate that this was such an obvious oversight on universals part in this saw design. It sounds like you are producing the same amount of volume we are so how often do you rotate those blades for sharpening purposes? we are awaiting arrival of our new set of blades and want to implement a rotation and sharpening schedule. We attempted to use a 1/16th thick piece of plexi today as a chip breaker which looked beautiful and cut better but the added thickness ruined the mitre angle. As a side note, I've been in contact with the Universal Arquati engineer who oversees the design of these saws about future improvements and I'll be discussing this issue with him as well.
 
By chopper, i'm assuming you are reffereing to a guillotine style chopper to correct any off angles from the saw. We have one of these and it tears up to Gesso something awful. Now, maybe we have a bad brand as when we purchased it, we were just getting started and knew next to nothing and it is now collecting dust on the shelf. Is there a brand you reccomend?

Yes, I did mean a guillotine style chopper. It is actually for cutting the angle not to finish off the saw cut. Personally, and I am going to hear about this from other framers, I think the chopper does a better job that the saw, at least better than the less expensive saws. About 70-80% of my mitres are cut with the chopper and my corners are perfect. I use the saw only for moulding wider that 3.5 inches or those that have weird profiles that are near impossible to chop.

The tricks of using a chopper is to take small bites, by that I mean don't try to cut the whole angle with just 1 chop, make at least 3 or 4 chops. Second and just as important as the small bites is to have good sharp knives. You can have the knives sharpened with either a flat ground or hollow ground. I like the hollow ground sharpening better because they seem to be sharper and actually peels the cut away from the moulding, sort of like a wood plane that rolls the wood out. Bad thing about the hollow ground knives is that they tend to dull a little quicker than the flat ground. The chopper itself is darn near indestructible. I recommend Morso because that is what I have and parts are readily available through Tech Mark in No. Little Rock. The only thing I have ever had to order is new bolts to hold the blades in place. There are other choppers and like I said they last for ever and I can't see much difference between any of them. Jyden was a very popular name but are now out of business, parts are near impossible to find so if I were buying I would steer away form Jyden. Hansen is another chopper and as far as I know the are still in business. Cassesse has a chopper and there are also some other brands out there but I would recommend purchasing a chopper that is made in Europe, I don't believe anyone in the US manufactures choppers.

The reason your chopper is tearing up the gesso is more than likely because you are taking to large of a bite and/or you knives are dull. If the knives are dull ship them off to Tech Mark, they sharpen my knives and do an excellent job. Hope this helps. Joe
 
Hey Kevin,
There has been times that I have had to use blue painters tape, which works most the time, but also a few times that I have had to used 2 ply mat board just to get the back of the moulding away from the fence so the knife is cutting not at the tip but in just slightly, it works. That is a good point you brought up, the mat board between the fence and moulding does act like a slip sheet and helps give you a clean cut on problem mouldings, nice call .

Another thing that I have found that if you align the knives near perfect where they meet at the front tip it seem help keep from moulding from chipping. I usually install the blades by first just snugging them against the chopper head and then aligning the very front tip so there isn't any overlap of either blade and then I tighten the bolt closest to the tip on both blades. If the tips are not perfectly align it will cause more chip outs on one side or the other. After I tighten the front bolts I then tighten the middle bolts and finally the last bolts. I can't remember who told me to do it that way but I'm going to say I think it was Baer Carlton. He use to be on the Grumble a lot and has some great tips - kind of miss the guy. He was another one that really like the chopper.

The mouldings I usually have problems with, both with the saw and with the chopper is the Asian mouldings. I believe the gesso they use is a little more brittle than the European, US, or Canadian made mouldings - but again that could just be my imagination :rolleyes:.
 
Just a little more feedback on the Morso chopper.

I have been in the business just over 35 years. I have been involved with cutting (either myself directly, or in close proximity of those doing the same) the entire time.

After about 20 years, since I was then in charge, I bought a Pistorius double miter saw to increase production and minimize personnel burnout. However, after about 3 years we sold it and bought a second Morso.

A couple caveats:
1) Even though we are a "distributor" we are a relatively low volume one. For sure more than the average frame shop but also for sure less than the average distributor.
2) Everything we cut is a solid hardwood with traditional finishes. No "snotwood", no gesso.

Blades properly sharpened makes a huge difference. While it's not cheap, especially considering shipping both ways, but we feel that having Tech-Mark* doing our sharpening is worth it, even though it means shipping half way across the country.

*Tech-Mark is the official US face of Morso, and have the Morso produced sharpening system on hand to keep your knives in factory condition.
 
Just a little more feedback on the Morso chopper.

I have been in the business just over 35 years. I have been involved with cutting (either myself directly, or in close proximity of those doing the same) the entire time.
Blades properly sharpened makes a huge difference. While it's not cheap, especially considering shipping both ways, but we feel that having Tech-Mark* doing our sharpening is worth it, even though it means shipping half way across the country.
*Tech-Mark is the official US face of Morso, and have the Morso produced sharpening system on hand to keep your knives in factory condition.
Yep.

Quoting myself from an earlier post on the thread...
Ha!:p
Hey, I know what you were saying, Joe.;)
I have been a major supporter of Tech Mark for many years.
Jill at Tech Mark has been very helpful for a long time.
http://www.tech-mark.com

Also, buy the wooden blade shipping boxes that Tech Mark sells.
I used to send my blades to them years ago in the original styrofoam boxes until one time the blades came back and they had started to poke out of the styro and cardboard box to the outside.
I wouldn't want the UPS guy to loose a finger trying to deliver the blades.:eek:
 
David: fascinating to hear that you went to a second Morso.

I use twin Dewalts on moldings with detail, and the Morso on smooth-surface stuff, like those cheap blacks, where I need a knife-sharp join. But, I use a pneumatic Morso, which is fast. And with my torn knee, much easier to use when you only have one good leg.

Are yours manual?
 
Should you use a chip breaker when cutting Aluminum?
We recently got a second Pistorious for cutting ALuminum, and it does not have a Chip Breaker, or anyway to easily add one. I have been considering modifying it.

Brian
 
Should you use a chip breaker when cutting Aluminum?
We recently got a second Pistorious for cutting ALuminum, and it does not have a Chip Breaker, or anyway to easily add one. I have been considering modifying it.

Brian
You don't need a chip breaker for aluminum.
Sometimes when cutting wood, you can have issues with wood grain, knots, gesso and such and the wood will tear away, chip or splinter at the bottom of the cut.
Aluminum will not have a problem as long as you don't try to cut too fast.
Just let the blade do the work and don't force the cut.

I've been cutting metal and wood for 48 years and I have never had an issue with aluminum moulding.
 
Yep.

Quoting myself from an earlier post on the thread...


Also, buy the wooden blade shipping boxes that Tech Mark sells.
I used to send my blades to them years ago in the original styrofoam boxes until one time the blades came back and they had started to poke out of the styro and cardboard box to the outside.
I wouldn't want the UPS guy to loose a finger trying to deliver the blades.:eek:

Direct link to those boxes? Can't find it on website
 
Direct link to those boxes? Can't find it on website
It's been a number of years since I got the wooden shipping boxes.
I hope that they still offer them.

You can actually bolt the blades in place in the wooden boxes so they won't shift or move.
I found this link...
http://www.tech-mark.com/morsochopperinfo
Screen Shot 2017-12-07 at 9.18.00 PM.png

Or call them or email them to see if they still offer them.
Screen Shot 2017-12-07 at 9.12.37 PM.png


Also, if you read the link describing the Morso blades and how they are manufactured, you can realize how the knockoff blades from China and Japan don't measure up to the quality of the steel and the machining that the real Morso blades get.
You get what you pay for.
 
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David: fascinating to hear that you went to a second Morso.

I use twin Dewalts on moldings with detail, and the Morso on smooth-surface stuff, like those cheap blacks, where I need a knife-sharp join. But, I use a pneumatic Morso, which is fast. And with my torn knee, much easier to use when you only have one good leg.

Are yours manual?

Yes, both manual.

And believe it or not, your leg doesn't get tired from operating the foot lever. It's the one you're standing on that needs a break first. We encourage ambidextrous operation to reduce the likelihood of repetitive stress injury.
 
Steve, It's hard to say how often to sharpen blades because there are many factors that can wear a blade down. We actually go by feel. If I start to feel the blade pulling the moulding it's time to ship in for sharpening.
 
Steve, It's hard to say how often to sharpen blades because there are many factors that can wear a blade down. We actually go by feel. If I start to feel the blade pulling the moulding it's time to ship in for sharpening.
I agree with that Mike, at that point the blade is crushing the wood and pulli g the moulding in, you will start to get gaps on the inside edge of the mitre
 
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