The Square Head Thread.

[pmcgee]

Paul, just keep an eye where the gent has his fingers, one cutter will take a lot more that the other, I'll stick with pregnant.

Sure, I understand. I just meant as far as the blades acting on the wood, I couldn't see that these would change ...

1) presentation angle of the cutting edge to the timber, and its capacity for tweaking (via projection, not grinding)
2) adequate support for the cutter

Love to see a pic of the cutter-head on your Cooksley, if you can manage it Paul, I have seen pics of your beast before, next door to you would know when to get up ...lol
Melbourne Matty.

I had some pics here, and it refers to the video.
https://www.woodworkforums.com/f163/cooksley-thicknesser-170384

I'll get some photos of the actual head ... although I'm sure I have photographed it before.

When I got the blades sharpened initially, the guy tut-tutted about the non-closed slots.

Cheers,
Paul

[L.S.Barker1970]

Sure, I understand. I just meant as far as the blades acting on the wood, I couldn't see that these would change ..

When I got the blades sharpened initially, the guy tut-tutted about the non-closed slots.

Cheers,
Paul

Ahh, my bad, your right yes, because of the small projection on planers and thicknessers it does not change much.
The rule mainly applies to moulding profiles where there can be variation of the depth and change in projection.

Closed slots are a bit of a false comfort any way, lets face it if the bolts are loose in any way the blades will move forward and will do damage.

Melbourne Matty.

[jcge]

John, fantastic summery, thank you.
I think you have it all there in a nut shell.

I wouldn't mind expanding on all of those as soon (if that's ok) as I can get some decent computer time.

Melbourne Matty.

Matty - I wasn't trying to load you up with the task of elaboration, but if you're happy to, I'll certainly be reading !!!

I generated the list in the context of moulding (vs jointing and planning) and it's reminded me of Scrit's excellent writings on spindle moulder tooling on the Canadian forum.

edit.... added link to Scrit's writings
https://forum.canadianwoodworking.co...hlight=moulder

John

[jcge]

edit.... because of the small projection on planers and thicknessers it does not change much.
The rule mainly applies to moulding profiles where there can be variation of the depth and change in projection. ....edit

Melbourne Matty.

Thanks for clarifying my post Matty
Regards,
John

[L.S.Barker1970]

Matty - I wasn't trying to load you up with the task of elaboration, but if you're happy to, I'll certainly be reading !!!

I generated the list in the context of moulding (vs jointing and planning) and it's reminded me of Scrit's excellent writings on spindle moulder tooling on the Canadian forum.

edit.... added link to Scrit's writings
https://forum.canadianwoodworking.co...hlight=moulder

John

No problem John, but to save me some writing work any way it might be a good idea to introduce some useful reference books here as well.
I will push on ..

2) adequate support for the cutter

This is an important part as the very design of the square head cutter has the potential to pull apart under load, the spinning force and the cutting action creates the tendency to lift the cutter edge from the cutter block.
First of all lets cover knife Projection limits, below is a good reference chart for Solid HSS cutters, Laminated cutters you could halve this chart again.

Also with cutter support this is why bolt condition is of the upmost importance (I will cover more of that next).
US Author W.H.Rohr in his book Machine moulder Practice has a whole chapter of bracing suggestions for heavy work none of which I have ever seen over here in Australia but thats not to say that it has not been done.
I have used thicker knives before when I need to run a deep cut, I do find that thicker knives run smother as they absorb much of the shock of a cut.
Here are some more useful reference books that I have read over the years and found very handy.

Principles of Machine Woodworking Four-Cutter Practice, by A.H.Haycock.

Cutters and Cutter-Blocks Stafford Ransome.

Machine Moulder Practice, W.H.Rohr.

Melbourne Matty.

[jcge]

Great references Matty - most (me included) wouldn't know where to search for such info
John

[jgforsberg]

thanks so much Matty for bring froward your knowledge and experience with this tooling. As always your notes are top shelf. Was surprised the tipped cutters don't reach as far a solid, and surprised how far solid do reach( 4 time thickness) Wow. those knife holder are cool and what an idea to support deep cuts. learning lots in this thread.

As a side i got an email from a gentleman with a 16" wadkin plate head that he has had the knife shatter into 100 or more pieces when planing a 8/4 12" board . No harm but i was surprised. Must have been a fracture or fault in the steel is my guess. the slotted knifes are hard to get and i had wounder if stock knifes had then been used and slots cut with a EDM and if some how that changed the property of the steel. I know lots of the tool grinders are using EDM to cut profiles to speed up grinding time and have not thought that to be a problem with the knife stock. What are your thoughts on the use of EDM for your solid and tipped cutters.

[L.S.Barker1970]

thanks so much Matty for bring froward your knowledge and experience with this tooling. As always your notes are top shelf. Was surprised the tipped cutters don't reach as far a solid, and surprised how far solid do reach( 4 time thickness) Wow. those knife holder are cool and what an idea to support deep cuts. learning lots in this thread.

As a side i got an email from a gentleman with a 16" wadkin plate head that he has had the knife shatter into 100 or more pieces when planing a 8/4 12" board . No harm but i was surprised. Must have been a fracture or fault in the steel is my guess. the slotted knifes are hard to get and i had wounder if stock knifes had then been used and slots cut with a EDM and if some how that changed the property of the steel. I know lots of the tool grinders are using EDM to cut profiles to speed up grinding time and have not thought that to be a problem with the knife stock. What are your thoughts on the use of EDM for your solid and tipped cutters.

Hi Jack, sorry Im days out here, had some big jobs to get out before Easter so no Toaster time here till now.
Thanks for you kind comments Jack, I've been keen to get a thread like this going on this subject as I mostly use square head tooling and wanted to share my experiences, good and bad.
I'm reluctant to use tipped cutters for big projection, the steel backing is much softer and doesn't have the support, in the Pic the text books state that this is the projections limits of solid HSS, I was surprised also, but as I have said, I would always take or reduce timber as much as possible so the cutters are removing very little and not under big loads.
Jack up till now I had not heard of EDM, I would be concerned about excess head generated from the process, and, would this change the steel in any way as you say ?.
I'm not sure on the finish either, rough perhaps ? cutters may need some additional grinding to finish.

Melbourne Matty.

[elanjacobs]

I also had never heard of EDM and I agree that the heat build-up might be an issue. Weinig rough out their pre-made profile knives with water-jet cutters to get around that problem.

[ab1]

This is a fantastic thread. As I've previously posted, I have a Wolfenden 20" square thicknesser from around the 1950's. I have been thinking about updating due to safety concerns, however, after reading this, I'm having second thoughts. The cutterhead appears to be in good condition, however, the bolts appear to be original.
I have 2 questions if I may.
1. The blades are reaching the end of their life. Where do you suggest I purchase new ones from? I'm located in Wantirna.
2. How do you go about setting the cutters on the cutterhead?
Cheers,
Andrew.

[Allison74]

Lots of brilliant info. Matty. I don't have any square heads but some of the cutters on my Mill are bolt on in a very similar way and I worried about some of the more extreme projections.

Thanks for getting this going.

Have fun,
Alli

[chambezio]

What an informative thread this has been!!!!!
I have a Macson/Barker 12" Jointer that has a round cutter block with knives that are about 5 mm thick, while my 12" Thicknesser, a Jeffwood, has a square cutting head sporting knives that are 12 mm thick.
I watched Norm mill some architraves using a "lunch box" type thicky with custom ground knives. I figured that the Jeffwood could do the same job and probably a bit better due to the bulk of heavy cast iron.
I asked one tool sharpening crowd in Sydney about cutting some knives for it and they told me to go back to the manufacturer and source them from there. I wish!!
Do you know of a crowd that could make some profiled knives in Aus?
Its a fancy full notion, I have, to get cutters to run a particular moulding for a job as being retired I don't really have a project in mind that would warrant the expenditure
Its been great reading about what these "old" machines were capable in their day and really they are still capable even with the authorities doing their best to get them out of the picture.

[pmcgee]

Some pics as requested ...

I have last used it while making a front pergola-type thing out of some pretty solid 2" 2ndhand hardwood
... planing completed ... pergola, not so much.

So I cleaned up one side, they both had some melted paint build-up on the blade.

20150404_131848 (Medium).jpg 20150404_131901 (Medium).jpg 20150404_131933 (Medium).jpg 20150404_131918 (Medium).jpg 20150404_131924 (Medium).jpg

and the maker's mark on the blades ...

20150404_132444 (Medium).jpg

[L.S.Barker1970]

This is a fantastic thread. As I've previously posted, I have a Wolfenden 20" square thicknesser from around the 1950's. I have been thinking about updating due to safety concerns, however, after reading this, I'm having second thoughts. The cutterhead appears to be in good condition, however, the bolts appear to be original.
I have 2 questions if I may.
1. The blades are reaching the end of their life. Where do you suggest I purchase new ones from? I'm located in Wantirna.
2. How do you go about setting the cutters on the cutterhead?
Cheers,
Andrew.

Hi Andrew,

Great questions, and you have a lot of options there, top of the list would financially not be a spiral head, not cheep but a beautiful thing none the less.
second could be chasing a second hand circular head with thin knives, as many thicknessers are being converted to spiral, the old head can end up being sold of, then getting it fitted up to your Wolfenden, bearing journals turned down to suit, etc.
Another is to have a head made up from scratch, this could be expensive also, finding a good fitter and machinist may also prove to be a challenge.
These are all good options, but money must be a big consideration, if you get a heap of use out of your thicknesser then it may be wise.

As for your Square head options, Jalor Tools PTY Ltd. - About - Google+ are great saw Doctor's, and will make up a set of blades for you, but they will not be cheap as there is a substantial amount of milling and slotting work to cut the recesses for the bolts not to mention the outlay for the blanks of HSS.
If you are friendly with some one with a milling machine yes, perhaps purchase your own HSS blanks of steel and cut your own slots, there are a few places that can supply just the material, I know one such place, but PM me for details as I will not recommend them for any thing else except to supply HSS steel.
Andrew, check the condition of your Bolts also, for wear and stretched threads, if any thing looks suspect replace it even all of them, its not worth the risk.

Setting your Square head thicknesser is easy, get a hold of two super hard plastic blocks out of such products as Vesconite for instance, size 35mm X 16mm X 100mm.( the 16mm thickness must be accurate) the hard plastic will not damage the new sharp edge of the blade.
Place your blocks at either end of the cutter-head resting under the cutter-head but laying flat on the bottom thicknesser table, move the table adjustment up to 16mm on the rule.
Set your sharp blade on to the cutter-head and do up bolts finger tight allowing a small amount of projection, overhang/projection on the cutter-head may differ according to the roller and chip breaker positions, I usually start with around 5 to 7 mm and see where it goes.
Rotate the cutter backwards buy hand until the cutter blade point touches the hard plastic block and the bolts only being hand tight will allow the cutter to find its own height of 16 mm from the table, its a bit of a feel thing but you should be able to feel the cutter touch the plastic block and move into position, if it misses the block, simply loosen the blade, bring the blade out further and repeat the process.
A small brass or copper hammer may be used for any fine adjustment to the blade, then a final tighten once you are happy with the settings.


Melbourne Matty.

[L.S.Barker1970]

Lots of brilliant info. Matty. I don't have any square heads but some of the cutters on my Mill are bolt on in a very similar way and I worried about some of the more extreme projections.

Thanks for getting this going.

Have fun,
Alli

Thanks Alli

I have seen some of the cutters that come with those pattern milling machine, scary, ya but amazing too.
Alli I honestly think you will be fine, small controlled cuts on those machines, there's heaps of adjustment there too.
Those mills are also so big and substantial that any cutting chatter will just be absorbed too.
Im so looking forward to seeing it run.

Melbourne Matty.