Can anyone comment on how to attach corrugated knives to molder head? How tight should the screws be tightened? The distributer suggested using a torque wrench. I am not aware of a torque wrench which will drive an allen wrench. Does the blade have to fully seated in the head or can it be set further out to provide more cutting depth? Thanks for your time.
Rick
Replies
Moosewood ,
I use collar knives but want to warn you to please be very careful , in fact do not spin any cutters until you are sure you have a firm grasp and handle on the what's up with collar knives .
The knife should ride in the majority of the corrugations , the screws you speak of , are they set screws that screw the collar halves together ?
The profiled portion of the knives extends beyond the collar .
If so it is my understanding these screws keep your setup while not in use or prevent the knives from moving .The spindle nut holds the whole Marianne together in reality . I use old school knives that have no corrugations they are angled the same but smooth a few of my collars have set screw holes to keep the set up .
I would tighten down the spindle nut then put the set screws in and you will be good to go . Always provide a safety shield between you and the cutter upon the first time you turn on a new set up , just in case .
Please ask questions and get more info before you really use these .
I am not trying to discourage you from the value of collar knives in fact you and I and only a small handful of Knotheads have fessed up to still using them , much to the dismay of the naysayers .
be safe
dusty , was shaper guy all day today
dusty,
One shop I worked in, used a collar type cutterhead similar to yours. Had a big nut on the top that held all together. First time I used it , the boss told me how to set things up. "Tighten that big nut up just as tight as you can get it," he said,"Then, give it another quarter turn." Instead of grinding the knives in pairs, to save money, he had one blade in each profile, used with another the same width, but pulled back in the head so it was out of the way. That is, until a fellow was running a cutter that was extended way out there, taking a heavy cut, and it broke off. Flew the length of the 40' shop, bounced off the far block wall, and buried itself in the back of a piece awaiting repairs. I was near the back wall, and looked across the shop at the guy running the shaper. He was pale as a ghost, looking at his hands, then his belly to see if he was all intact. I have one of those things. Matched knives, and light cuts, for me.
Ray
Ray , Yup , the old steel collar knives can break off especially when they do extend too far or in the case you speak of they were not balanced well or at all .I was taught to actually use a scale a weigh the knives for balance .The setup you saw most likely was vibrating the machine across the floor , sort of , I tried that once , had to change my drawers after that one .
I use one knife on a very few small profiles usually when I need to match something for someone either moldings or even sidings for houses but only small bites .
I have never had a collar knife fly out or break .
As far as these being too dangerous to use , that is not my opinion and the analogy I use is this : have you ever broke a tooth or teeth off any carbide blades or break a chip or part off of a shaper or router cutter ? I have .
The question I ask is where did the carbide or teeth go ?
My point is metal can go flying regardless of the exact cutters and tools and common sense and safety must be observed , but as you know there are no guarantees in life .
dusty
"I have never had a collar knife fly out or break ."
And you never will if you keep those threads and meeting surfaces clean and those threads very lightly oiled (self preservation = suitable torque efficiently applied) and if you use "laminated steel bar specially made for Spear and Jackson for moulding cutters-or similar".
Are french heads used/known in America?Philip Marcou
Morning Philip ,
I guess the ,laminated steel bar stock you speak of is what we call high speed tool steel that I make my knives out of ?
I have only seen but never used nor known the French head to be used personally by anyone .Are there advantages or operations that makes the French head desireable ? I thought I remember it being cast out as un safe .
I basically reef hard on the spindle nut , no way I care to leave it partly tightened .
dusty
The head that seems to be talked about is called a lock edge collar and came in two versions. The old style which was two circles with a v notch in the top and bottom. The newer safer model had a worm screw which engaged the knife and kept it from sliding out. I never had any problems with the newer lock edge type. It had two bolts to hold it together so you could take it out and keep it's setting. We had them with built in ball bearing rub collars. The nice thing about them was you could change the knife projections for rabbetts and such.
Seems there is a lot of confusion between corrugated heads and lock edge or bevel edge heads. Completely different tooling. Corrugated is the newer, safer, more common one seen today.
I've used French head knives. The advantage is for short runs. You grind the knife from carbon steel and you only need to grind one edge to the exact profile. The other edge is slightly undersized. The real advantage is the knive is centered in the post so the profile is what you get. Most folks don't realize standard cutters cut on the chord so the profile ground is not the actual shape that is cut. There's complicated formula to grind standard cutters. You can't make a cutter any faster than a French head. It actually cuts by the scraping method so there is a slight disadvantage and like I said it's for short runs
I was taught to take the piece of molding you want to duplicate a cutter for and cut it on a 45° angle on one end and trace that profile to be ground .
My collars are the older style bevel edge .
dusty
I have not seen the french heads listed in any of my catalogs. (Garngia/Leitz/FSTool/Royce/Amana/LRH/Freud...).
If anyone is interested, Weinig USA has a video on their website showing the grinding of a profile. Quite the process, from making a template for hogging much of the material and then it is programmed into the computer for final sharpening. The vid doesnt go into great detail, but it does give you an idea of the process when you order custom knives.
Brad
You will not find any info on French heads on those sites. You will only find French head info in old technical text books. You cannot even find much on lock edge or bevel knife heads on the web either. Not everything is on the web. The old ways will always still have info the web won't. There was an article in FWW years ago showing how to figure the geometry for grinding cutter heads. 45 degrees is a real ball park number.
French heads are pretty much gone. A french head is a not really a head at all. It's more a shaft with a slot in it to hold the knife. There is a threaded hole to accept a bolt to lock the knife in.
Rick , you are right the 45° is way ball park , however it will get you in the ball park . I think the idea is similar to when you cope the end of a piece of trim , the theory is like . I have matched many a profile with this method , it sure is no where near as perfect as the original , but no complaints in the last 25 years or so , in fact folks with obsolete needs are sooooo happy when they find I can help .
dusty
Dusty,
"I guess the ,laminated steel bar stock you speak of is what we call high speed tool steel that I make my knives out of ?"
No, I am talking about bar stock specially made for planer knives and shaper cutters. It is 1/4 inch thick by various widths and lengths. it consists of a 1/8th inch thickness of hss welded to a softer backing steel which is not brittle like hss-to give it strength. You merely cut the soft steel with a hacksaw and snap off the rest- grinding a thinner section of hss is a lot easier. I still have some here and have often considered making a few blades for my custom planes with it.
Rick has answered your questions on the French head right on-except that in my part of the world we were sure NOT to use brittle high carbon steel for this and used the stuff mentioned above.
Getting and grinding an exact matching profile for shaper knives is quite easy-the trick is to make a template from thin sheet steel or aluminium which you get from a full size drawing. The template is then handy for checking as you grind and for recording the profile.
The attachment shows the method I am familiar with. FWW on Making and Modifying Woodworking Machines page 73 also sets it out nicely.
Those who say "get on with woodworking and stop futtsing about with yer tools and machines" are leading a half life, for sure, as this sort of tool making is to me, at least, part of the trade and certainly advantageous- one can make or reproduce any shape.Philip Marcou
That's a good book. A bit simplistic but more detailed on some of the more esoteric elements of machine tools. Still only touches on the subjects though. Obviously a UK publication. Covers machines most folks in the states never heard of.
The intro from the "Woodworkers Bible by Alf Martensen is dedicated to an old plant manager who hired me as a wood machinist to bring a new department of 32 mm machinery online. It's a good book. Unfortunately there are few really dedicated in depth books on tweaking machinery and tooling. This info is handed down from one worker to another as most of these folks aren't very bookish.
Edited 9/23/2008 7:49 am ET by RickL
Philip ,
Thanks for the explanation and info on the laminated stock no , I have never used it . It sure sounds easier to use then hss , a real pain to grind into pieces and such .
I see how a template or sketch will duplicate profiles dead on for a French style head but when I do the bevel edge knives I take the profile we want to reproduce and cut it off on a 45° angle and I use that for my profile template , Rick felt the 45° was a ball park figure , I have had success with it .
I suppose the angle the slots are cut through the collar where the cutter protrudes is what makes the angle different , or as you said they tend to cut on a "chord" is this what you mean ? and is the angle constant with this type of collar knife ?
regards from Oregon
dusty
Dusty,
Here is a more detailed description , but it shows a single slot type. As far as I know the angle is constant- I have two sets of slotted collars with parallel slots so by geometry the angle is the same.
I have never tried your 45 degree method but if it gets near enough it would be a lot easier than having to draw and extend all those lines.Philip Marcou
"except that in my part of the world we were sure NOT to use brittle high carbon steel for this and used the stuff mentioned above."
Kind of reading info between the lines. We used a softer carbon steel. Certainly not brittle at all. One would have to bend it back and forth multiple time to break it. It was a softer steel than HSS steel for short custom runs. More like the steel on a plane iron. That was the beauty of the French head.
Philip ,
Add to your comments about having the ability to create any profile we want or need to , it is a part of the process that few get involved with and I do feel fortunate to have learned from the passed down information of several old timers .
Soon there will only be memories of folks grinding their own cutters , I have never turned one down I always do my best to fill the bill , I have made miles of moldings and different parts of old local buildings and such . This avenue although not in high demand locally is a true specialty and when the folks find I can make or may have the cutter they need , I'm only too happy to oblige .
Enclosed is a picture of some of the hss cutters I purchased from the last and largest local mill house at auction 20 years ago or so , there were all together over 200 profiles , I paid $150 I know the steel was worth that .
The other picture is a Rosette cutter I designed but was made by a machinest pal , it paid for itself real quick .
thanks for your time Mook
dusty
This discussion on blade cutting is very interesting and it seems unless people work with someone such as yourself, this aspect of woodworking could disappear. I know the last customs I had cut I never even contemplated finding a craftsman to cut it and I ended up paying around $400 per pair of 4 1/2" custom profiles from Weinig.
Pretty cool, but definetly something a person would need someone such as yourself to teach them.
Brad
"Pretty cool, but definetly something a person would need someone such as yourself to teach them."
Depends on the individual and their training. I had done a lot with setting up and running lock edge collars and had also done some profile grinding for moulders on a profile grinder. I learned how to grind cutters by hand because of necessity. I was working in a shop and I needed a certain profile and the local sharpening shop wasn't considered that good for custom. My metalworking expereince and an old article in FWW was all I needed to start grinding my own knives. This article goes way back when FWW was in it's heyday.
Get "Cutterheads and Knives for Machining Wood" by Chandler Jones. Available from 206 301-4367 or Knife Grinding and Woodworking Manual by Charles Monnett available from http://www.cggschmidt.com Both bookjs show how to use the projection scale to size the profile right. It's more on par with 30 degrees than 45 degrees.
brad ,
I am by no means an expert at knife grinding . I learned out of necessity much as Rick did , I learned to grind by hand . A profile grinder works much like a key cutter if you will . Once the template or pattern is in place the skills required are of a machinist type to operate the machine .The more artistic ability one has the better on stuff like this imo especially for hand grinding and drawing in general.
The cutters made professionally that you bought are of a much ,ore consistent quality than I can produce by hand , the price you paid sounds a tad high but the size requirements you had were larger than what I would do . We have ground 2 knives to split the detail when it is taller then our spindle will allow.
I think Rick and Philip can give more technical information from the industrial experiences they share and Philip's knowledge on sharpening in general is awesome .If I can help anyone on this type of cutter or collar don't hesitate.
regards dusty
I dont plan to grind my own, but it is interesting to hear the discussion of how it is done. I am too much of a nervous nelly when it comes to the shaper to try anything. I try to stick to the cutters that meet the euro standards.
I had another set of custom blades cut by a machinst closer, but I think the Weinig quality was better, plus they have far more steel options to choose from. As a plus, they are pretty great to deal with to, but I have been told GC Schmidt is about the same.
By the way, dont sell yourself short. I can tell you know a whole heck of a lot more about this than me.
brad ,
what type of machine do you use that will turn 4 1/2" tall cutters ?
What profiles did you have made for you just out of curiousity ?
dusty
I have a 4hp Hammer saw/shaper and for this one I use a Garniga 4" dia insert head. The under the nut for the shaper is 4", and truthfully I had to shim up the top of the hood to get it all to work. The profile stuck up a bit and extended below the head. I was making base trim and window casings. The casing profile was less than 4". The machine was ok for power, but I wish I had four knives to get more cuts per inch. I have some pics at my other computer if you wanna see.
Brad
You can purchase Allen head sockets at pretty much any store, though I have to admit that they would only come in certain sizes
Mark
Dear Dusty,Thank you for your thoughts. It had not occurred to me that the spindle nut would help hold the knives in place. I appreciate your thoughts on using a safety shield at start up. Rick
You are unclear as to whether you are talking about a corrugated molder head with corrugated back knives (45 or 60 degree corrugations), or a split collar head with loose, notched knives. Big differences. You post made me think corrugated back knives, but the responses were for split heads.
Dave S
Dave , you are right , could be a different animal then I thought .
d
You are correct, I was referring to a corrugated head with corrugated knives. After reading the posts yesterday, I installed the knives, tightened the set screws, mounted the head and then re-tightened the set screws. I hid when I turned the shaper on the first time and did indeed take light cuts.
Thanks for your helpRick
Molder heads with corrugated knives are quite safe. The same technology is in heavy use in molders, every day. Weinig supplied large Allen wrenches with their heads, and the wrench had give to it when the screws were tight. Very safe. As for the split collar tech, when I started work as mgr of a mill that had a bunch of old (and abused) equipment, we needed to make a few feet of molding. I told the employees we would do this on the shaper. They all went white, and started mumbling to each other. Later, the fellow that I appointed to make the molding came up to me and nervously explained that I had just given him a death sentence. Apparently, some budget-minded predecessor had taken old files and ground a sort of bevel on them to fit in the collars, then cranked down the spindle nut with a 4' long pipe extension. This still allowed about a third of the knives to be thrown out at any point in the run, terrorizing everyone in the shop. They wanted to refuse to run the shaper/Death Machine, but didn't want to buck the new boss either. We got thru that molding, and ultimately ended up with a new shaper, bigger spindle, new collars, knife stock with the safety notching, and a great array of profiles to use. We still broke a knife every now and then, but with properly guarded and fenced and powerfed set-ups, no one ever came close to an injury. Dave S
Hi Dave S,
I'm glad enough questions were asked to determine what type of molding head/collar the OP has.
Just like the workers you described a wee bit nervous when the thought of the collar knive death machine being used I too was concerned when I thought the OP was asking for "how to " use the older versions like I use over the internet .
That made me nervous for the user and is why I was so darn adamant about him not spinning those just yet .
regards dusty
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