Remanufacturing the guard on a Wadkin AC

[L.S.Barker1970]

An interesting task at the moment is remaking the guard on this very early Wadkin cross cut saw, I have made a ply template to cut my 2mm sheet metal out to and made sure I was happy with the fit.The saw is a monster, with a 700 mm blade that gives a full 8 inch cut along with 12 inches of reach. I will try to keep you all up to date on how the build goes, so enjoy ....
http://i982.photobucket.com/albums/ae301/matty355/matty355001/y3mYdvhU7L-C0_DfA6PFT0CeiaNLBnTVX9SzvJVnAfWma1qAOaKzWVZA0J6p5rEcSGTcZp_yIn1j2ZbT6O74wNVkzy3ouFj65zMGazHfaKZXkfFPx5Nf9qoSeA5_zpsnwa3rxqo.jpeghttp://i982.photobucket.com/albums/ae301/matty355/matty355001/y3mt_nCqv6srkN483Ahtf6a5sSko7folRP2MAg1bmgBxvi-lATQjQe7iCc8mVUzDNY6isa_it_p_IjT4X5STT_LA7JGEMMZKnj7-W6I3ajWZ0vnnFHVcFC8QNOn_zps5rxvf8fw.jpeghttp://i982.photobucket.com/albums/ae301/matty355/matty355001/y3mWyyPtgGPgz1chcdJMyYDx-0vnt5HomGJDfRlKYXeBT3RqP6aNMT5ZA7WWqg_ugvg9x--0312_tufZye7ECaSKJdnzNI3HtZo46Av-ZaXG7pl4REsEb6uRaiL_zpswko04gsk.jpeghttp://i982.photobucket.com/albums/ae301/matty355/matty355001/y3mIQrNgCVM3-sWqn9gFKTLKWr2dZR-EHlT2avTSEIpOrKMMtDRwxunmsaTlv1cAA_uRTacPp7M0F1Vw16Mh3pBXbmcYOgYGZls3-P5dFUPx84R9TLUrcSP-PQK_zpsmjmwyclz.jpeghttp://i982.photobucket.com/albums/ae301/matty355/matty355001/y3muqD_8otAKnUMj2Kel6Y20DpbnGSMdgMgTPf4hAESimFSHln1BHcufLNGChxWeXR7kSCtVzUqaUXvCV23kJdFeEj1t7IgzFy8IhFCcfMW5KxWPTQhuqoplwtb_zpspwubcnze.jpeghttp://i982.photobucket.com/albums/ae301/matty355/matty355001/y3mkWD25ij5IOKCblCdaY8Z56ZB3thb3l7e8kx_pNHlWccZcjls_vzEpZCk6mb6137H9dFeL2kBJvYl3sQ-P9Shb_hq1vmuINNf12U_Tk_OXracOec8P1SWoDAk_zpssqbkrztr.jpeg

http://i982.photobucket.com/albums/ae301/matty355/matty355001/y3mfn8Z3aqe9WJICGdZg3j4R_VYl5X5ZYviR1VdsDEib4ajK8hdSv_fJby23cHse5MPGZ_pLflpHLgzDgjR2dcc016XlVSjcaD0s916xgIktqZVJ5lBAfddZ4w5_zpsaefmrhbq.jpeg

http://i982.photobucket.com/albums/ae301/matty355/matty355001/y3mGAVS-l-GESsQG3QgPzHeRQJPyfOngAGEENEFLmqFwjs0VRDdfZggxLwMvK_QMDW9iiozzeZgLWo8yo0HaEuExBXLrq7rq83xFRMGWEdpiAE0QRcQef7tnuEd_zpsx9tih31t.jpeg

Melbourne Matty.

[Allison74]

Now he's bringing out the serious toys!

700mm crosscut saw.
You are going to have a few of those puny 450mm CC boys all upset.:D

There's a bit of timber stacked there no wonder you need a serious saw.

Have fun,
Alli

[camoz]

Matty,

That's an interesting project you have there, please do keep us posted! I think I can see a Wadkin CD in the background, so there is plenty of saw for all that timber:D

what's the HP on that AC Matty?

Cheers,

Camo

[auscab]

Nice big saw pictures, 700mm blade on a cross cut ! Fruit
I wonder what it's like if one of them jams in a bit of wood like my 300mm one does.
Maybe a little chest of drawers next to the machine with a change of under pants for the operators is needed :)
How are you joining the metal , Arc or Mig ? One of us will get a Tig one day , that would be nice for that, neater, but i suppose it all comes out the same with a grinder.

Rob

[BobL]

Interesting and nice bit of kit there!
It looks like it has a pneumatic Ram on it or is that just a damper of some kind?

At the mens shed we have a Nolex 3P RAS and while it only has a 12" blade that thing still worries me.
It's so quite and runs for such a long time after it is turned off that it represents a real risk to (especially novice) users who need to manipulate timber near the still turning blade.
Because of this I was thinking of trying to incorporate some sort of a braking mechanism to stop it quickly when it is turned off.

Not many people realise that RAS have a much higher rate of accidents than other saws amongst DIY and professionals alike. They appear safer because the risk of kickback is lower but the fact that they are often placed up against a wall can mean pieces come bouncing back at the operator at all sorts of wild angles. The other is it can pull wood and any operator trying to hang onto it into the exposed blade. This is where a full covered blade such as found on a modern SCMC is a safer system.

Despite this I'm looking forward to seeing what you come up with.

[L.S.Barker1970]

Hi Alli, yes its a biggin !
We have a job coming up that requires lots of big cuts, short sections and square cuts.
Thanks Cam, it has a 2.75 HP motor and does 2800 rpm, it makes some air and noise when it runs !
Rob if it jamed it would be scary !
I'll probably arc weld this all up, my mig is not running at the moment.
Bob, you have good eyes, it is air operated and a brilliant set up !
The seceret to not jamming a cross cut or radial saw is consistency in the cut.
Any lunge during the cut results in jamming, the air ram provides a good consistent cut and is adjustable, Scarry to watch running but I will be fitting up a full cage around the machine so it will be very safe to operate.
I'll get the guard around the blade done first, then the aim is to get the benches and fence stops set up, sort out the bugs that way we can see where the cage guards need to be.
Thanks for all the comments everyone

Melbourne Matty.

[L.S.Barker1970]

At the mens shed we have a Nolex 3P RAS and while it only has a 12" blade that thing still worries me.
It's so quite and runs for such a long time after it is turned off that it represents a real risk to (especially novice) users who need to manipulate timber near the still turning blade.
Because of this I was thinking of trying to incorporate some sort of a braking mechanism to stop it quickly when it is turned off.



Bob, just a thought, does a VFD unit brake the motor ?
We had a nolex docker where I did my apprenticeship, nice machine, made in WA from memory ......

Melbourne Matty

[elanjacobs]

That's a serious blade :oo:
No vibration/resonance damping though, so I hope it doesn't shriek like one of our blades does (we don't use it any more)

[BobL]

Bob, just a thought, does a VFD unit brake the motor ?
We had a nolex docker where I did my apprenticeship, nice machine, made in WA from memory ......
Melbourne Matty

Good point but a regular VFD would't have enough resistance built into it's bracing circuit to handle the angular momentum of even a small blade so it would have to be fitted with a heavier duty braking resistor.

The mens shed would probably be unwilling to shell out on a VFD to do this up front. I'd have to demonstrate it to them and that might convince them ;-)

[jgforsberg]

http://www.aconcordcarpenter.com/wp-content/uploads/2011/02/100_2053_1-e1298400031918.jpg

How needs a guard for a docker? Matty that AC look very modified?

[fletty]

Good point but a regular VFD would't have enough resistance built into it's bracing circuit to handle the angular momentum of even a small blade so it would have to be fitted with a heavier duty braking resistor.

The mens shed would probably be unwilling to shell out on a VFD to do this up front. I'd have to demonstrate it to them and that might convince them ;-)

In an earlier life manufacturing electric motors, there was an installation of high level exhaust fans where the insurer insisted on brakes on the fans so that they couldn't assist any potential fires. There was VERY high inertia in the fans and rotors and mechanical braking resulted in ...... mechanical breaking! We eventually satisfied both the owner and insurer with simple DC injection and I was quite amazed that the progressive injection of only 0 to 9VDC was sufficient to stop the fan from running and to prevent any 'environmental' running due to ambient airflow.

fletty

[hiroller]

DC Injection Braking. https://en.wikipedia.org/wiki/DC_injection_braking
Learn something new here everyday!

[Allison74]

http://www.aconcordcarpenter.com/wp-content/uploads/2011/02/100_2053_1-e1298400031918.jpg

How needs a guard for a docker? Matty that AC look very modified?


That 2" steel tube rail is just to hang his coat on when it gets hot.
He's at least 3 feet to the side, it's hydraulically controlled and the machine does have a guard.

Still a scary saw. Not a job for the fainthearted or those who want to keep their hearing.

Have fun,
Alli

[auscab]

That 2" steel tube rail is just to hang his coat on when it gets hot.

Alli

No , that's for the pole dancing routine going on while sawing . I could see Matty with one of those in his shed .

:D:D:D:D:D:D:D:D

Not a kinky thing, a fitness thing.

Rob.

[Allison74]

Somehow the image of Matty pole dancing is just a little too much.
But maybe, you never know!:rolleyes::rolleyes:

Have fun,
Alli

[L.S.Barker1970]

How needs a guard for a docker? Matty that AC look very modified?

It is Jack, but we still have a heap of work to do on it !
That's a great pic you put up, that is what we were after and then the wadkin came along !

Melbourne Matty.

[L.S.Barker1970]

Somehow the image of Matty pole dancing is just a little too much.
But maybe, you never know!:rolleyes::rolleyes:

Have fun,
Alli

You guys come on !
As if I'd have a pole....
In the family room .....
For fitness ......

Melbourne Matty.

[jgforsberg]

Matty is that an air cylinder ? If so you might want to consider a dead man switch . Scene one or two of the CC's run auxiliary motors off of the break end of the motor for more power . These were strictly cross cuts at 90 saws . Will you be incorporating a nose guard And a dropbox ?

Imagine steel is easiest to work with and of course that metal has a reassuring strength to it . Manufactures Tended to makes it these in aluminum or brass not because of the strength but because of the fear of a spark entering the dust collection should the blade hit on the jam up. I see yours has got the short Arbour?

[BobL]

Matty is that an air cylinder ? If so you might want to consider a dead man switch . Scene one or two of the CC's run auxiliary motors off of the break end of the motor for more power . These were strictly cross cuts at 90 saws . Will you be incorporating a nose guard And a dropbox ?

Imagine steel is easiest to work with and of course that metal has a reassuring strength to it . Manufactures Tended to makes it these in aluminum or brass not because of the strength but because of the fear of a spark entering the dust collection should the blade hit on the jam up. I see yours has got the short Arbour?

Another useful reason is that if the guard makes contact with the running blade the guard doesn't damage the teeth.

[L.S.Barker1970]

Matty is that an air cylinder ? If so you might want to consider a dead man switch . Scene one or two of the CC's run auxiliary motors off of the break end of the motor for more power . These were strictly cross cuts at 90 saws . Will you be incorporating a nose guard And a dropbox ?

Imagine steel is easiest to work with and of course that metal has a reassuring strength to it . Manufactures Tended to makes it these in aluminum or brass not because of the strength but because of the fear of a spark entering the dust collection should the blade hit on the jam up. I see yours has got the short Arbour?

Jack its an after market festo air ram
Foot pedal operated and adjustable.
The switch gear needs work, emergency stops mounted close to the operator and possibly a dead mans switch, although I'd like to know more about them !
The cage surround should suffice for a nose guard and was thinking of a gap in the table for ofcuts to drop through, not sure, still rolling around some ideas ?
Jack and Bob I might be making a steel guard only because I have the tools to do so.
I don't have access to a tig welder for ally.

Melbourne Matty.

[BobL]

I don't have access to a tig welder for ally..

There'a always pop rivets :-) - have a look at this http://www.woodworkforums.com/f200/generic-2hp-10-planer-thicknesser-dust-control-issues-204634

[L.S.Barker1970]

There'a always pop rivets :-) - have a look at this http://www.woodworkforums.com/f200/generic-2hp-10-planer-thicknesser-dust-control-issues-204634


Very tidy work Bob !
I probably could of looked at aluminum with that in mind but I already had the steel kicking around the shop.
Many thanks for all the suggestions so far, goes to show there is a few ways to skin this cat here !

Here's the progress so far ......

http://i982.photobucket.com/albums/ae301/matty355/matty355001/y3meZMVnnpbHDhEP3TPIZ2sUAoYz59nBmsrLkggEVQHOAH_dG22HXn53pYgJbi8bezX0jbqG9WmR8ydgtBGqDG7_WeQz7qPZSjF6sVNMPGnY3i6A5dud8TEgRpo_zpsppwbecg3.jpeg
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http://i982.photobucket.com/albums/ae301/matty355/matty355001/y3mReeYOq_Vk8gWaVHs3EELlvqABvMtR1nb305SQGsy4c_5V8sQYbZfshN2G7RHuQYEbVVSSmqvdWff8ukglfzOKD0Z63lTQFKpBng7L6G6NXTCk7Wq34lleWFq_zps5lvuvpkr.jpeg
http://i982.photobucket.com/albums/ae301/matty355/matty355001/y3mIPjdw-m4OO6oSZr2VHHvJJrx44d-vKHGAxQFtkma8M8eZL4gokHSCvgDdBH1x1ypRfL_XV9ADV00jZrmYR5owE27KsL9F0f7nNzSnTbvLZa8R9m2MMjpD3ph_zpsjc2qd458.jpeg
http://i982.photobucket.com/albums/ae301/matty355/matty355001/y3mM7yk9gKZ4pqstsvTL77VRBoJq6uUdU2VluFJDwPvOXvH9XctEuhg6Qrh6qymHAwNOPHfmVCrT5lmuZTkj--t4JPuFhwebI_7tKXTfpTUSCM6vSV2XXDY81eD_zpswrrbsljd.jpeg
http://i982.photobucket.com/albums/ae301/matty355/matty355001/y3mmoccUJJxr6eHzHyV83lf3n6_olEySUATnQdcnXo_reL0UeU-lMlWm7E7M_uLl5JrW3ctL2rWRCAflxYYzVWCe-eXYjUuaK5LEyhhZItZ2nPIBygDnSjP6Z9F_zps5t0kkb6b.jpeg
http://i982.photobucket.com/albums/ae301/matty355/matty355001/y3m7APH5v8CI68iY4eNtMGSvsqlUjcXz3L9xirZOS55wolq3Zt8j-U3mDerY-Ou3Zl9igsGzmgNWUxte5uG9Nrt1T57ElY5oHlbhF3IBem4ePpTon57FyZqF1iX_zpsexvmgxkf.jpeg
http://i982.photobucket.com/albums/ae301/matty355/matty355001/y3mB5921PO41Jz1c6CF374OV9BXCOEDj6oUKV_hb_BAj7GitTlvH3iQlg2WyKRO7QSr7ZBaGcS5WhOelpx550O-LH4GGhlD3kjhFR0NiaKSH_bXMHGsgel-8jQx_zpsmbxwucxh.jpeg
http://i982.photobucket.com/albums/ae301/matty355/matty355001/y3mC5u7hSVI_DlQSnNOn-od3GZ4dMgMfzP8iTETbJmaL_0hYVE52Mgwq_DRV9KBXGKEmALM5RZLIBTWgKNoKnh0qgj9iu4CHdTifqrIL27o1wfsd7W8WtUm7gBz_zpskznxtyfl.jpeg
http://i982.photobucket.com/albums/ae301/matty355/matty355001/y3mALz1Wzn_31DWJSsMK_rYiWfRl3W5PUHoE_aHC-Bmy4tMxOu073A2o39O2e8bIrX_lmQOiZ1BWmlsePn4HFMSbVhHKdgv4QjDbUgvUJoLKchmRuQ3W_5JgyJ7_zpsdctlnrca.jpeg
Melbourne Matty.

[jgforsberg]

looking good Matty. do you take it off to change blades?

[L.S.Barker1970]

looking good Matty. do you take it off to change blades?


Thanks Jack !!
Just the outside cover comes of
There were 2 covers made, outer and inner, there will be a couple of heavy duty catches to keep it together and possibly a hinge !

Melbourne Matty.

[jgforsberg]

Thanks Jack !!
Just the outside cover comes of
There were 2 covers made, outer and inner, there will be a couple of heavy duty catches to keep it together and possibly a hinge !

Melbourne Matty.
I see it now. What might look cool is a motor end bell welding on the face where the washer is. What you got looks good too. I like the hole,

[L.S.Barker1970]

I see it now. What might look cool is a motor end bell welding on the face where the washer is. What you got looks good too. I like the hole,

jack I was thinking the same thing !!
Although the washer looks very steam punk !!
Lol

Melbourne Matty.

[Allison74]

Hi Matty,

Looks good!

I take it that the few rough spots in the rim weld are deliberate camouflage, patina! They are "age defining character" sort of like grey hair and wisdom.
I like the Steampunk idea. Much better than trying to be a slave to politically correct "authenticity".
Your big blade is going to make quite the music in that guard, a bit of a resonance chamber.
At least there will never be a question of whether it's On or not.

Have fun,
Alli

[L.S.Barker1970]

Hi Matty,

Looks good!

I take it that the few rough spots in the rim weld are deliberate camouflage, patina! They are "age defining character" sort of like grey hair and wisdom.
I like the Steampunk idea. Much better than trying to be a slave to politically correct "authenticity".
Your big blade is going to make quite the music in that guard, a bit of a resonance chamber.
At least there will never be a question of whether it's On or not.

Have fun,
Alli

Hi Alli,

Rough spots indeed, lol..!
Thats just me being lazy, stick welding is not an ideal application for this type of work, the rod when brought to the edge of the work too long basically melts every thing and has to be build up again.
Its times like this I miss my old Mig welder, I'll get it repaired soon, its just an earth problem that I can't solve, so needs to be looked at.
My Brother is a gun welder, he would say Tig on this guard, his welding is just beautiful, hot rod chassises, stainless steel you name it he can weld it.
The big blade was turned on yesterday and yes it's got some speed, made the first cut through a rather large 150 x 250 beam.
I noticed a very small drop in tone as it made the cut but it powered through.
What's going to be key I think is to maintain a sharp blade at all times, either that or modify the motor for more HP/torque and less RPM.
I noticed our Wadkin CD docker only runs at 1440, that seems a more ideal cutting speed than 2800.

Melbourne Matty.

[Allison74]

Hi Matty,

I still say you should claim it as deliberate artistic character creation!:D

My brother and nephew weld like that, I just go and buy beer. Much easier.

2800 rpm, that's over 20,000' per minute with that big blade, that definitely sounds too fast. Serious business!

Have fun,
Alli

[jgforsberg]

Matty I have a VFD on the one saw and am going for one on the CC mostly for the brake. I do have a 500mm blade that i run at 45 hz for thick cuts on the Delta 40C. the problem with the lower speed on the DD saws is you give up power the lower the HZ and the 5 hp is a little shy to begin with. In my research i found high speeds blades from Linbide saws
Guidelines for using Linbide Saw Blade (http://www.linbide.com/guidelines_saw.php)

and there 500mm recommended speed is 90m/s max rpm is 4000.

as i said my saw has a brake and i just finished a drop box


https://www.youtube.com/watch?v=59FZaGEyx4Y

[Allison74]

Matty I have a VFD on the one saw and am going for one on the CC mostly for the brake. I do have a 500mm blade that i run at 45 hz for thick cuts on the Delta 40C. the problem with the lower speed on the DD saws is you give up power the lower the HZ and the 5 hp is a little shy to begin with. In my research i found high speeds blades from Linbide saws
Guidelines for using Linbide Saw Blade (http://www.linbide.com/guidelines_saw.php)

and there 500mm recommended speed is 90m/s max rpm is 4000.

as i said my saw has a brake and i just finished a drop box[/QUOTE



A 500mm saw @ 4000rpm is 104.6m/s that is 15% over the maximum recommended safe speed for cutting hardwood and still above the max for softwood.

A 700mm saw @ 2800rpm is in the same position with a speed of 102m/s.

From Linbide's guide

[QUOTE]he following table indicates the maximum revolutions within acceptable safety limits and without impairing the use of the saw blade, As a rule the optimum operating R.P.M. is 20% to 35% below the maximum operating revolutions. Generally saw benches, portable saws and cut-off saws have a peripheral cutting speed of 50 to 60 m/sec.

The recommended rpm's for a 500mm saw are 2300rpms at 60m/s, that's 33% below their max recommended speed for hardwood and a bit more for softwood so a bit higher is not going to be drastic but. So one would assume their recommended max rev's for a 700mm blade is going to be significantly below 2800rpm.

The 500mm blade on my Pickles saw @ 2800rpm is 73m/s.

Have fun,
Alli

[jgforsberg]

I thought Motor RPMs were 2850 ? Are you guys not on 50 Hz ? I'm spinning my blades 3450 .

[Bohdan]

I thought Motor RPMs were 2850 ? Are you guys not on 50 Hz ? I'm spinning my blades 3450 .

A 2 pole motor runs at 2850 rpm but a 4 pole motor will give you 1425.

[jgforsberg]

A 2 pole motor runs at 2850 rpm but a 4 pole motor will give you 1425.
Oh i thought Matty only had One Pole:D

[Vann]

...it has a 2.75 HP motor and does 2800 rpm, it makes some air and noise when it runs !


700mm crosscut saw.
You are going to have a few of those puny 450mm CC boys all upset.http://d1r5wj36adg1sk.cloudfront.net/images/smilies/standard/biggrin.gif She's right Matty.

I've been looking at the specifications for the CC. It has 5hp to spin an 18" blade at ~3000rpm. Your AC has just 2¾ hp to spin that wopping great 27½" blade at about the same speed.

Inside the blade guard of the CC has “AC 419” cast into the 18” blade cover...

392953

...suggesting that maybe the AC was only intended to have an 18” blade. Are you sure that puny motor will handle the large blade?

Cheers, Vann.