Making your own Spindle Moulder cutters WIP

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If it worked well for you grinding your own, that’s brilliant, it’s a skill and a knowledge that is becoming increasing rare.
It's not that difficult once you get into it. Also sometimes useful to be able to modify an existing cutter.
It's pretty much what the old chaps would have done making moulding plane blades, except it's HSS and uses angle grinders and bench grindstones
 
I recently picked up an older version of this profile grinder. Viel profile copying grinding machine | Elite Tools Put the blade blanks in your preferred cutter head. Mount it in the machine and start grinding the profile of the template you made. Tilt the grinder each side for a little side relief and the cutters are balanced, will cut equally and match the profile. :) I suppose it is halfway to hand grinding and ordering in what you need.

Pete
 
Making your own cutters is an art form in itself. While there are many over the counter options, you need to do a cost performance analysis of why your doing this. My two shapers are vintage Oliver 287 shapers. These do not support metric cutters. So I have had to make spindles for these machines to accept mainly 30 mm cutters. I have also dealt with odd cutter designs that are no longer in production or use.

Matching profiles such as cope and stick cutters require very precise tolerances. Profiles that are decorative and stand alone can tolerrate a bit more slop. So I prefer using euro insert cutters for the precise work. Felder, Garniga, Lietz and others have many options in the insert market.

When you need a few feet of odd ball molding, you often resort to using cutter blocks with corregated knives. Th ese are the most popular when you have knives ground to a special profile. Slip knives are also useful but you need to know what your doing or you may be headed to the ER.

The misconception about corregated knives is that they dont cut on both profiles evenly. No matter how accurate you are, this is a fact of life. So what I always did is to offset one knife by one notch in the head to force one knife to finish cut and the other to tag along and do rough cutting. This also kept the cutter block balanced. While doing this forces you to reduce your feed speed for surface finish, the limited number of feet needed did not present an issue. Running production runs of tonque and groove in high numbers can benifit from a more precise setup and I have since gone to an insert head for this type of job.

Grinding corregated knives is best done on a profile grinder. My last shop used a wynig profile grinder. Smaller more hobby like machines such as the viel profile grinder can certainly help in this regard. Here you grind both knives at the same notch setting to get them as identical as possible.

While carbide inserts have come a long way in the euro insert heads, carbide never had as keen an edge as that found on tool steel stock. Older cutter heads often used brazed carbide knives attached to a steel body. The issue here is that the carbide that can tolerate the brazing temperature could never hold a perfect edge. Inserts use a different grade of carbide which cannot tolerate the brazing temperatures; however, outperform the the edge quality of brazed knives. Certainly carbide can tolerate much longer runs than steel but steel provides a superior edge.

If you only use a shaper or molder for limited use and low volume runs, you may find using steel knives an advantage. Sharpening between runs is easy. I dont really care if the cutter block is a safety design or not. If you set up shapers routinly, you know where those knives are. So using standard, old school corregated blocks is a no brainer. Grinding knives on a grinder such as the viel is easy once you read the manual.


The problem with grinding your own knives is you get spoiled. A few years down the road, you wind up with a entire tool cabinet full of knife sets. Used once twenty years ago and never used since. I often kept one off knives thinking that another profile may pop up in which I can regrind an old obsolete knife set into a new profile. But I still have lots of knives.


One advantage of using hollow and round molding planes is that you can create any profile you want and your not limited to commericial offerings. When you grind shaper cutters, you can do the same thing. Use a commercial profile when its easy and functional, grind a custom profile when you have to. Some of my profiles are for french spindles. French spindles are rare and some consider them dangerous.

The shaper is often the queen of the shop even if you have CNC capabilities. A molder or shaper can run circles around a CNC mill for cutting stick. I will always have a Martin, Robinson, Hoffmann, or oliver shaper parked next to the fancy german CNC router for this reason. Unlike modern managers, I need to the job done and out the door. I have actually ground knives on a profile grinder for use with cutter blocks on the CNC router.

While this diatribe does not answer specific questions, it does offer an insight to this area of woodworking.
 
Grinding cutters is not something you want to do unless you have the tools and skills to do it, for many just drill bits is enough and why larger industries have a dedicated toolroom for the purpose of this task.
 
Grinding cutters is not something you want to do unless you have the tools and skills to do it, for many just drill bits is enough and why larger industries have a dedicated toolroom for the purpose of this task.
My last shop had a dedicated toolroom and we did grind some knives. But the labor costs add up and we often found it cheaper to use a dedicated tool vendor to grind knives. We emailed the .dwg files to CG Schmidt in New Jersey and within 48 hours, Fedex dropped off the knives. When we did grind knives, it was often the result of water poor planing by our management and we had to grind knives on Thursday or Friday, work are tails off on the weekend and hopefully, we were loading the truck on Monday. Truck chasing is no fun and you can imagine the poor language coming out of the machine department when this happened.
 
Making your own cutters is an art form in itself. While there are many over the counter options, you need to do a cost performance analysis of why your doing this. My two shapers are vintage Oliver 287 shapers. These do not support metric cutters. So I have had to make spindles for these machines to accept mainly 30 mm cutters. I have also dealt with odd cutter designs that are no longer in production or use.
Not sure what a metric cutter is - it would make no difference to the old cutter shaping methods. Old 1 1/4" blocks can sit on 30mm spindles with "hi hat" bushes
Matching profiles such as cope and stick cutters require very precise tolerances. Profiles that are decorative and stand alone can tolerrate a bit more slop. So I prefer using euro insert cutters for the precise work. Felder, Garniga, Lietz and others have many options in the insert market.
Cope and stick is modern machine joinery needing two very precise cutters as you say. This is avoided by just using one "stick" cutter, much as you would with hand moulding planes, then joining stile to rail the hand joinery way.
When you need a few feet of odd ball molding, you often resort to using cutter blocks with corregated knives. Th ese are the most popular when you have knives ground to a special profile. Slip knives are also useful but you need to know what your doing or you may be headed to the ER.
Corrugated blocks hold non-corrugated cutters very well and hence can be very versatile - you don't have to have corrugated cutters.
The misconception about corregated knives is that they dont cut on both profiles evenly. No matter how accurate you are, this is a fact of life. So what I always did is to offset one knife by one notch in the head to force one knife to finish cut and the other to tag along and do rough cutting. This also kept the cutter block balanced.
Yep. Usually just an unmatched but balancing (non) cutter. You only need one to cut. Never a problem.
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The problem with grinding your own knives is you get spoiled. A few years down the road, you wind up with a entire tool cabinet full of knife sets. Used once twenty years ago and never used since. I often kept one off knives thinking that another profile may pop up in which I can regrind an old obsolete knife set into a new profile. But I still have lots of knives.
Some cutters get reshaped and ever smaller until you end up with what looks like a box full of shrapnel! One advantage of this ever expanding collection is that you can often buy them on Ebay for very little, then throw a lot of them away and just re-use or modify the good ones. Makes a spindle cutter cheaper than a cheap router cutter.

One advantage of using hollow and round molding planes is that you can create any profile you want and your not limited to commericial offerings. When you grind shaper cutters, you can do the same thing. Use a commercial profile when its easy and functional, grind a custom profile when you have to. Some of my profiles are for french spindles. French spindles are rare and some consider them dangerous.
I've got one French cutter but never used it though my first machine (AEG Maxi26 combi) had the slot for a french cutter.
They probably OK if small and no great depth of cut, and notched so the stay in the slot and can't fly out if coming loose.
The shaper is often the queen of the shop even if you have CNC capabilities. A molder or shaper can run circles around a CNC mill for cutting stick. I
Definitely!
 
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How does one mount a 30 mm cutter on a 1.25 inch spindle? T bushes are useful for going the other way. Many of my 30 mm insert heads were used on my old german shaper. Now I have 1.25 inch old world olivers.... TWO OF THEM and they are both cone heads. So I machined new spindles for the Oliver 287. I have 1 in, 1.25 in, 30 mm, 40 mm and 50 mm. All done in 4140 steel.

Another aspect of the Oliver 287 is that it was used in aerospace to machine airplane parts. Here, the shaper was equipped with a ZZ collet spindle to accept metal cutting spiral milling cutters. The one I got out of Boeing was missing this collet. Heck, it was missing everything. So I machined up a ZZ spindle to hold router bits. Later, I machined another one using ER collets as these are easier to find.

Sometimes, its just easier to use a router bit in a shaper. I have a number of pattern maker bits for use in making casting patterns. Some are just straight cutters with either a top bearing or a bottom bearing. Others have draft angle. One way I impart draft onto a pattern. These are not cheap. I use these on either my bridgeport milling machine or the oliver shaper with a collet spindle.

Some of my cutters are simple Freeborn cutters. Here, I used T bushes to take the bore from 1.25 in down to 30 mm when using the 30 mm spindle on my old Hoffmann shaper. Now I just use the 1.25 in spindle on the oliver. I have a 1.25 in spindle to allow me to use some vintage ebay finds.

The only issue I have run into is using shaper cutters with 1/2 or 3/4 bores. The conehead design is hollow to allow for the retention nut and removal nut. So your limited to using a 1 in spindle for safety reasons. While I can rig up a 1/2 in straight spindle and then mount it in a ZZ collet to allow me to use these small cutters, I have not stumbled upon any of these cutters yet.

Jack from jack english machines, of Wadkin Temple Fame, turned me onto french spindles. They are an interesting type of cutter but not for everyone.

My most complex or vexing cutter work is not on a shaper but rather on my tennoner. The oliver used a strange coping cutter based on a square block. Because of the geometry, getting a profile grind correct on these is not easy. Its easier to use more standard blocks but the speed is half that of the shaper so I use custom brazed heads with six knives. Luckily I dont need that many profiles for the oliver 125. For my own use, I prefer the more shaker like profile on my personal doors. This allows you to simply bypass the two coping heads for the most part.

As you may guess, I do like shapers and dont need any more. But should a Robinson wander my way, I am sure I can find a home for such a wayward machine. I do like the Robinson.
 
Do you need corregated knife stock? No. The wedge system will hold the knife just fine. But I am lazy. The corregated feature allows you to quickly back set one knife from the other knife. Done by eye without the use of a setup jig and indicators. Often I had to setup the molder for S4S, then set up the molder to run ten feet of wacko molding, then switch back to S4S. Corregated knives made this easy. Now, I only use the shaper when its the best solution. Sometimes, its just easier to grab a hand plane or other tool of that ilk and knock off what you need to finish. Its a judgement call as to how much time you spend in setup versus how much time you spend in doing the actual cut.
 
Corrugated blocks hold non-corrugated cutters very well and hence can be very versatile - you don't have to have corrugated cutters.

Are you out of your mind?! This is such a horrendously dangerous practice and nobody should replicate it! You’re at least halving the surface area that’s clamping the cutter as compared to a regular Whitehill style block.
 
Are you out of your mind?! This is such a horrendously dangerous practice and nobody should replicate it! You’re at least halving the surface area that’s clamping the cutter as compared to a regular Whitehill style block.
Halving the surface area = doubling the pressure.
With the same torque on the nut the corrugated jaws would give a firmer grip on a flat cutter than flat jaws, due to the corrugations, gripping like teeth. Effectively more friction.
 
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Halving the surface area = doubling the pressure.
With the same torque on the nut the corrugated jaws would give a firmer grip on a flat cutter than flat jaws, due to the corrugations, gripping like teeth. Effectively more friction.

Completely incorrect superstition, High Speed Steel is much harder than the body of the block and it will not “grip like teeth”, if nothing else you will cause irreversible damage to your corrugated cutter block, causing the corrugations to not interlock with the correct cutters properly anymore.

Absolutely insane.
 
Completely incorrect superstition, High Speed Steel is much harder than the body of the block and it will not “grip like teeth”, if nothing else you will cause irreversible damage to your corrugated cutter block, causing the corrugations to not interlock with the correct cutters properly anymore.

Absolutely insane.
Sounds like guesswork to me!
HSS is much harder than the flat faced block too.
 
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Jacob if your belief on corrugations and smooth surfaces was correct then industry would have adopted it long ago. After all it is cheaper to make smooth heads rather than corrugated ones so they would only have bothered to make the knives with the grooves instead of both. There is a reason all shanks of milling machine cutters are very smooth. Even drill bits would be sold with ridges in them rather than smooth. In fact bits that have become scored from spinning in the chuck get to a point that no mater what you do they spin even in a better chuck.

Pete
 
Sounds like guesswork to me!
Completely incorrect superstition, High Speed Steel is much harder than the body of the block and it will not “grip like teeth”, if nothing else you will cause irreversible damage to your corrugated cutter block, causing the corrugations to not interlock with the correct cutters properly anymore.

Absolutely insane.
Not really. While you may see some flatening of your corregations, they have the clearances of a class 3 thread or worse and have rounded tops like threads. Most modern blocks use a wedge to hold the cutter in place. The corregatons are more for alignment than anything else.

I have actually made corregated blocks using thread mills to cut the grooves. The modern ones are basicly jointer heads with grooves. I do know of some older gib designs that allowed knives to fly out but those have not been used since the 1940s. My 12 in northfield jointer had one such head and it was replaced with a modern head prior to me getting this 1943 jointer.
 
Jacob if your belief on corrugations and smooth surfaces was correct then industry would have adopted it long ago. After all it is cheaper to make smooth heads rather than corrugated ones so they would only have bothered to make the knives with the grooves instead of both. There is a reason all shanks of milling machine cutters are very smooth. Even drill bits would be sold with ridges in them rather than smooth. In fact bits that have become scored from spinning in the chuck get to a point that no mater what you do they spin even in a better chuck.

Pete
It's not a "belief" it's just that I came by a corrugated block and have no corrugated cutters and can't see why I shouldn't use it with plain cutters. Will certainly take notice of any evidence to the contrary!
 
Jacob if your belief on corrugations and smooth surfaces was correct then industry would have adopted it long ago. After all it is cheaper to make smooth heads rather than corrugated ones so they would only have bothered to make the knives with the grooves instead of both. There is a reason all shanks of milling machine cutters are very smooth. Even drill bits would be sold with ridges in them rather than smooth. In fact bits that have become scored from spinning in the chuck get to a point that no mater what you do they spin even in a better chuck.

Pete
The corregations save a massive amount of time in set up. Setting knives in my tennoer head is a time consuming task requiring the use of set up jig and indicators. Setting up a molder for S4S using corregated heads takes me less than 15 minutes to set and check all FOUR heads. I have used plainer steel to make shaper knives in a pinch with no ill effects.

There are shaper knives that have corregations along the edge and not on the back. These are a totally different animal. Here, the groves or notches are used to lock the knife. Like I said, totally differnt animail.
 
Sounds like guesswork to me!
HSS is much harder than the flat faced block too.

Yes, but when a flat cutter is in a flat-faced block with a good amount of surface area there is no way anything can deform unless you lean on the spanner with a scaffold pipe and overtighten it.

Clamping a flat cutter in a corrugated block may work once, twice, or maybe even ten times, but eventually with every tighten of those cutters in various positions will cause small amounts of deformation to the peaks of the corrugations because between each corrugation there is nothing to support it so it will invariably marr. Possibly, it may marr by an amount not even perceptible to the eye, but enough that eventually your clamping surface of corrugation peaks becomes quite inaccurate with sections more deformed than others, which will be a recipe for disaster as the surface area of one of the clamping faces is reduced drastically and the chances of a cutter shooting out are increased drastically.

Just use the right cutters in the right blocks they are intended for, it's not exactly rocket science for ducks sake.
 
.......Possibly, it may marr by an amount not even perceptible to the eye, but enough that eventually your clamping surface of corrugation peaks becomes quite inaccurate with sections more deformed than others, .....
You could just as well argue that with more use the corrugations would bed in and be more secure, not less.
I wouldn't argue either way but these various safety block designs are much safer than the square block in your post above (Thursday), as long as they are tightened up and the clamping is in good condition - not splayed open with over tightening as per Trevanion's photo some time ago.
And power feed or two push sticks + Shaw guards etc. every time!
 
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When we did grind knives, it was often the result of water poor planing by our management and we had to grind knives on Thursday or Friday, work are tails off on the weekend and hopefully, we were loading the truck on Monday. Truck chasing is no fun and you can imagine the poor language coming out of the machine department when this happened.
Isn't it strange that getting a rush last minute order from a customer is always managements fault.
 
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