Bottom Blade wrench assist screwdrivers - source wanted.

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Antbr123
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Bottom Blade wrench assist screwdrivers - source wanted.

All,

I am struggling to source a GOOD hexagonal or square shafted screwdriver to remove bottom blade screws which are slotted c'sunk 9/16" (14.1mm) wide heads.  This would allow wrench or spanner use to give me extra torque.  Searched "t'internet"....faced with usual myriad offers guessing at what I am really after.  

 

Does anyone know of or have a recommended manufacturer or source where I could buy one? If so can you send me web link so I can find?

 

The screws are stubborn little b.....ds! And its now descended into my will versus theirs!  But I want the right tool for fear of mashing them up and having to drill out.  I have applied heat a number of times.

Tony

wristpin
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The screws are possibly BSF c

The screws are possibly BSF c/s with a slightly raised head ?  - expendable as readily available. I'm assuming that you don't have welding facilities but I would find a friend with a mig and get him/her to weld a nut on edge or a bit of scrap steel to each in turn so that it can be gripped with Vise/Mole grips and unwound while hot. See my Project Anzani thread which was a bit tricky as the screws were slightly below the surface of the bade and I had to avoid welding them to it. 

Back to your question. I have Snap-on screw drivers with a hex below the handle that takes a 1/2" AF spanner for good leverage and a similar Stanley that I've had since I dabbled in Lambrettas in the late 50s. The wooden handled Wm Maples screwdriver belonged to my Dad and has a flat that can be gripped with an adjustable spanner of Vise/Mole grips - not that I would!!! 

My local Antiques Centre (part Junk Shop) has several boxes of large screwdrivers at a couple of quid a time that could have flats ground on the shaft for gripping or even a T bar welded on without breaking the bank. 

  

 

Antbr123
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Angus - some good suggestions

Angus - some good suggestions and thanks for the ideas.

The screws are a mixture of raised and flat head.  Probably all raised originally, but worn down by being scraped .  Unusually, I think they are 3/8" BSW thread....the thread seems quite course. Ive not given up yet....!!  Marples made some good tools.  Ive still got my Dads box-wood wood chisels....Unfortunately, all of my heavier duty screw drivers have round shafts. But I may still try to get a mole grip locked onto the shaft and try that before purchasing a PROPER screwdriver!!.....Needs must when the devil drives!

Tony

Antbr123 (Tony)
Consider grass in terms of how you would like to be treated yourself - and you won't go wrong!

wristpin
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3/8” diameter ?  Seems a bit

3/8” diameter ?  Seems a bit hefty for a push mower, but JPs were a bit over engineered !

Antbr123
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As the advert goes !Should

As the advert goes !Should have gone to SpecSavers!"  Yep I'm the guy who could shear a sheep dog....

I should have read the drawings closer.  The screws are 5/16" x 3/8" BSW C'Sunk Slotted. They are buggers to find, through I think Garfitts hold them.

 

Antbr123 (Tony)
Consider grass in terms of how you would like to be treated yourself - and you won't go wrong!

wristpin
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That poor dog! Like the dead

That poor dog! Like the dead cat though.

These may be of use. Seems that Ransomes may have something of interest.

  

Antbr123
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Like the dead cat or the

Like the dead cat or the advert??.  Dangerous waters Angus!  Having said that my rose bush has done well this year following the last few years fatalities! Buried with full agricultural honours!

Antbr123 (Tony)
Consider grass in terms of how you would like to be treated yourself - and you won't go wrong!

wristpin
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The advert!

The advert!

Chris G
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I've used the "MIG a nut on"

I've used the "MIG a nut on" technique on a motorbike sprocket recently and it works well, I think the heat it puts through to the thread also helps release.

Not a fan of using a screwdriver with a spanner as controlling the truness of the direction of rotation is tricky and can slip and burr the head up, I also don't see any real advantage over a long correct fitting screwdriver where you can get ample torque. For screws as stubborn as bottom blades can be, I think an impact driver after heat is the go to.

arnk
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Percussive maintenance

Percussive maintenance required ... my skill!

Clean out the screw slot with an old small screwdriver / chisel.

Soak in diesel, Plusgas or whatever potion you have to hand.

Wear thick gloves for when you hit your hand.

Use an impact driver (set to loosen "L"), hold bit firm in the rusted screw and strike the end hard with a big hammer.

Toolstation sell a cheap Draper like impact driver, but I can't vouch for how long the bits will last.

https://www.toolstation.com/impact-driver-bit-set/p90581?

If that fails then try a cold chisel and hit one side to turn the screw.

 

If you want a screwdriver for abusing with hammers and spanners then these have lasted at my work.

https://www.machinemart.co.uk/p/wera-6-piece-heavy-duty-chiseldriver-scr...

Al

wristpin
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Impact drivers have their

Impact drivers have their place but bear in mind what you are working on. If the sole plate is cast - either iron or ally there is a risk of ending up with needing a difficult to find replacement. It must be supported directly below the line of impact.

arnk
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Good advice, sometimes I am

Good advice, sometimes I am too keen to wallop first and think later!

olcadmin
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Personally, I have a fairly

Personally, I have a fairly large Stanley screwdriver with a hex bolster that I use for this type of job. It's at least 25 years old but the following seem to be modern equivalents:

https://www.amazon.co.uk/Stanley-FMHT0-62619-Bolster-Screwdriver-Multi-Colour/dp/B00SVDJ17G

https://www.amazon.co.uk/Irwin-Pro-Comfort-screwdriver-Bolster-SLOTTED-8mm/dp/B01N08ZEUM

https://www.machinemart.co.uk/p/blue-spot-12-piece-hex-bolster-screwdriver-set/

As an alternative, why not think about using a 1/4 or 1/4 inch T-bar socket spanner fitted with suitable converter and/or hex screwdriver bit? You should be able to get good torque out of that combination but with more balanced loading to minimise risk of burring the slot in the screw.

 

OLC Admin

Antbr123
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All good suggestions and

All good suggestions and kindly noted.

Thankfully I had a stock of blade screws and have managed to extract the old ones. I did purchase a square shafted animal of a screw driver which with repeated heat treatments to the screws, brake fluid mixed with the wifes nail polish remover and then followed by heat/quenching I managed to remove the little s...ds. The approach was complicated as I was removing the blade from an unusual aluminium knife frame on a JP Maxees MK1 dated 1947.  Normally the knife frames were cast iron. 

But thanks to all for the suggestions.  But the screw driver I purchased really is an animal of a tool and a worthy addition to my tool chest. Not cheap.

https://www.amazon.co.uk/dp/B002C5LD6Q/ref=pe_3187911_189395841_TE_3p_dp_1

regards

Tony

Antbr123 (Tony)
Consider grass in terms of how you would like to be treated yourself - and you won't go wrong!