I have just invested in an old Rapidor power hacksaw (one that takes
14" blades), and it is basically sound except for the spring loaded
lever assembly that engages the drive pulley. I am afraid the spring
broke so farmer joe got his welder out and made nasty repairs (really
truly nasty!!).
He also had a go at the (single phase) electrics and bypassed a
Dewhurst switch which I discovered tucked under the bed. But why would
you want a reversing switch on a power hacksaw, surely thats not
original?
If anyone out there has a Rapidor I would be interested if they can
shed some light on the drive bits, and also it would be handy if anyone
knows if they had a saw-activated electrical cut-off - via Dewhurst or
otherwise. In fact any info would be more than I have now.
Ta, Steve
We have a Rapidor with electrical cut-off etc. It's three-phase in case that
makes any difference.
Pic's available of whatever you need, but we are out for the day today.
Peter
--
Peter & Rita Forbes
Email: snipped-for-privacy@easynet.co.uk
Web:
I have a warco power saw with a electrical cut off which is basically stop
start buttons, you start it and a bolt attached to the saw touches the stop
button when finished. I to can photograph it if needed.
Martin P
Steve wrote:
Joules,
So thats what reverse is for on the lathe, unturning a little when I
have taken off too much ? Could also be used to undrill a hole when its
in the wrong place. Dead handy.
Steve
Thanks Peter,
I will be interested to know mechanically how the electrics are
switched off, your three phase switch may be a different type. My main
concern is the drive side, I'll try and grind off some of the welded-on
garbage. I can see the remains of a large spring which I presume holds
the pulley away from large boss on the end of the crankshaft. The
levers are inboard of the pulley and act to force the pulley into
engagement against the spring pressure - though it looks to me like the
gap is way too large. A second lever latches the first and the latch is
knocked out when the saw cut finishes.
The lot will have to come off and for the moment I am not sure if I can
get the boss off the end of the crankshaft. It looks like it could be
threaded with a splash of weld ! Or maybe its on a key and should have
been held on by a nut. If you have ever had yours apart and know what
goes on there it would help.
BTW I think the Brooks Gryphon motor is probably original, and wonder
what date that would put on it. Probably middle to late 50s I suppose.
I would be interested to know it age.
Steve
Thanks Peter,
I will be interested to know mechanically how the electrics are
switched off, your three phase switch may be a different type. My main
concern is the drive side, I'll try and grind off some of the welded-on
garbage. I can see the remains of a large spring which I presume holds
the pulley away from large boss on the end of the crankshaft. The
levers are inboard of the pulley and act to force the pulley into
engagement against the spring pressure - though it looks to me like the
gap is way too large. A second lever latches the first and the latch is
knocked out when the saw cut finishes.
The lot will have to come off and for the moment I am not sure if I can
get the boss off the end of the crankshaft. It looks like it could be
threaded with a splash of weld ! Or maybe its on a key and should have
been held on by a nut. If you have ever had yours apart and know what
goes on there it would help.
BTW I think the Brooks Gryphon motor is probably original, and wonder
what date that would put on it. Probably middle to late 50s I suppose.
I would be interested to know it age.
Steve
Thanks Peter,
I will be interested to know mechanically how the electrics are
switched off, your three phase switch may be a different type. My main
concern is the drive side, I'll try and grind off some of the welded-on
garbage. I can see the remains of a large spring which I presume holds
the pulley away from large boss on the end of the crankshaft. The
levers are inboard of the pulley and act to force the pulley into
engagement against the spring pressure - though it looks to me like the
gap is way too large. A second lever latches the first and the latch is
knocked out when the saw cut finishes.
The lot will have to come off and for the moment I am not sure if I can
get the boss off the end of the crankshaft. It looks like it could be
threaded with a splash of weld ! Or maybe its on a key and should have
been held on by a nut. If you have ever had yours apart and know what
goes on there it would help.
BTW I think the Brooks Gryphon motor is probably original, and wonder
what date that would put on it. Probably middle to late 50s I suppose.
I would be interested to know it age.
Steve
Peter,
If I have managed to overcome all the IT challenges, the problem area
is show at
formatting link
snipped-for-privacy@btinternet.com/P3120005.JPG
This is after sawing off the main bodge, but it suggests the end boss
is threaded but also tacked on to the end of the crankshaft with weld
(cringe!). Or is it not threaded, but keyed, and should be held on with
a long-lost nut ? It would be nice to know before I attempt to undo the
mess.
Thanks,
Steve
OK, I'll have a look at mine tonight, but it looks different.
The file size on that picture is 9mb uncompressed, you'd do better to reduce it
a tad....
Peter
--
Peter & Rita Forbes
Email: snipped-for-privacy@easynet.co.uk
Web:
Oops, it was a first attempt - will try harder next time. I think
Paintshop can do that.
There is a Rapidor for sale on eBay, its hard to make out from the
photo, but it looks similar in that area, and has the same lever
arrangement, though a different pulley.Mine has a layshaft on the
bottom level to increase the mechanical advantage for the single phase
motor and has V-belts. Others I have seen have the motor mounted at the
back - a more sensible location if you want to use suds.
Steve
That looks a very early machine, mine has the motor at the back, and has belt
drive to the gearing etc with a sheet steel cover over everything.
The ebay item looks usable, you would need to sort out some guarding over the
drive.
Peter
--
Peter A Forbes
Prepair Ltd, Luton, UK
snipped-for-privacy@easynet.co.uk
If you're talking about #7597485830, it's a Rapidor Machester Light
6 x 6" hacksaw of the 50s.
The motorised Manchesters with the motor mounted below with a
countershaft were still being made in the 60s.
Tom
Thank Guys,
The fact mine has a cast iron pulley probably makes it older than the
one on eBay. The matching base paint colour indicates the Brooks
Gryphon motor is almost certainly original, and looking in old ME
magazines it seems that was introduced in 1952.
I am glad to say the drive system has yielded to my ministrations. The
drive boss is threaded on, and the drive direction sets it firmly
against a shoulder on the shaft. I managed to grind off sufficient weld
(where the boss had been tacked onto the shaft) to get it off, and then
get enough weld spatter off the shaft to remove the pulley. I still
have the remains of the spring welded to both boss and pulley - its
quite a mess! Just about everything was welded to something else, but
it will all clean up. Finding a replacement spring may be a challenge,
but I am fairly confident I can get it back the way Rapidor intended,
and in all other respects it seems mechanically sound.
The electrical side is still a bit of a mystery. Even if original, it
seems pointless to have a Dewhurst reversing switch on a motor that
will never be reversed (as it would undo the drive boss). I suppose all
I need is a decent IP66 limit switch and a stop/go.
Steve
The Dewhurst switch is probably used as an on/off rather than reversing, and the
cut-off is basically a micro-switch operated by the frame in the lowest blade
position, so as soon as the material is cut through the motor is cut off. This
seems to work through the no-volt coil on the on-off switch.
Peter
--
Peter A Forbes
Prepair Ltd, Luton, UK
snipped-for-privacy@easynet.co.uk
Peter,
There are some old bits of linkage on the Dewhurst switch where the
lever and knob would normally be if fitted on a lathe, these are no
longer connected to anything. This suggests it was used as the cut off
switch. The mounting is fairly tidy, so maybe it was the original one.
The current wiring only has a bolt pressing a domestic light switch as
the cutoff, there is no on/off switch and no "no-volt" either - which
now you point it out would be desirable (more expense). All the current
wiring is going in the bin.
Steve
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