I've been looking around it and it seems in very good order, a 2 horse 3
phase motor that stands testing with my AVO, and nice unworn bearings and
slideways. The oil pump lifts the arm if I spin the flywheel by hand and the
'creep' facility seems fine too. Tomorrow I'm off to purchase a 3 phase
socket and try it out!
However the coolant pump is a bit of a mystery to be. There's a link from
the crank eccentric to the pump piston that is AWOL. I can make one easily,
but wonder if it should maybe be adjustable so as to vary coolant quantity?
I wish I could take a look at a genuine one.
Also, I cant work out how the pump should work. There seems to be a total
absence of valves around the pump unit,(incorporated into the bottom of the
iron casting that is the coolant tank) and at the delivery end there appears
to be one ball bearing that has an inverted cup sitting on it. Does anyone
have any experience with these things and can suggest how it's supposed to
work? There seems very little stuff on the www about donkey saws, this
should be a very useful little (well about 1/2 ton!) tool when it's up and
running.
Julian.
Are you sure that the part you're talking about is the coolant pump? I
have a Qualters & Smith power hacksaw, which I believe is fairly
similar. Your description sounds much more like the hydraulic oil pump
which raises and lowers the bowslide. Every time the pump's piston is
pushed into the cylinder, it raises the bowslide slightly. This should
happen on the return stroke. How quickly the bowslide falls depends on
the rate of leakage that you control using a valve. If it's the
hydraulic oil pump which is incomplete, the machine won't function
without it.
I may be wrong here. I'm just guessing. But if you think I can be of
more help, feel free to post here or to e-mail me at cdt22 AT cantabgold
DOT net.
Best wishes,
Chris
Sorry, I skipped over the first part of your post. Obviously it's not
the hydraulic oil pump. My apologies. I'm tired...
The Qualters & Smith uses a little vane or gear pump for coolant. It
sounds like the Wicksteed pump is rather different.
Is your Wicksteed the one with the rounded front end? Glad you rescued
it. Most of the old power hacksaws are great machines.
Chris
Thanks for the reply.
It has a hydraulic piston pump with two pistons, one big one small. One
seems to provide the 'lift' for the return stroke and the other seems to be
the one that powers the ''raise'' facility after cutting. I had to rebuild
this pump because it was full of cack and not working well. It's now working
perfectly and the saw blasts through RSJ material in double time. The two
horse motor is a huge thing for its power - must be very old, but the
machine is a brilliant bit of kit....
I'm now struggling with the coolant pump. As previously stated it is a
piston pump driven by an eccentric on the end of the ''crankshaft.'' I
machined up a bit of threaded bar to drive the piston from the eccentric and
now when it pumps it tries to rival Niagara Falls and swamps the delivery
cup and flex pipe. There must be a mechanism to regulate flow - it's not in
the delivery system because that is intact, so I'm thinking that there must
have been a mechanism to regulate piston travel?
Is anyone familiar with my old Wisksteed saw (weighs about 1/2ton) maybe has
one lying around or knows of any machine shops or suppliers that would be
happy for me to come along and take a look?
Cheers Julian.
Sorry once again for the response I gave last night. I was tired and
hurrying.
> It has a hydraulic piston pump with two pistons, one big one small. One
> seems to provide the 'lift' for the return stroke and the other seems to be
> the one that powers the ''raise'' facility after cutting. I had to rebuild
> this pump because it was full of cack and not working well. It's now working
> perfectly and the saw blasts through RSJ material in double time. The two
> horse motor is a huge thing for its power - must be very old, but the
> machine is a brilliant bit of kit....
It sounds like the Wicksteed hydraulic pump is somewhat different to the
Qualters & Smith pump. The Qualters & Smith pump has one piston and a
valve (which is part of the piston which lifts the bowslide) which
closes automatically when the bowslide reaches its lowest position.
When I was searching for a power hacksaw, I was told by a machine tool
dealer that the Wicksteed and Qualters & Smith machines were of a
similar quality, but that he thought the Wicksteed had the better
hydraulics and the Qualters & Smith the better bow.
The Qualters & Smith also has a two-speed motor, which is why the motor
is huge. I'm not sure if the Wicksteed motor is the same.
One thing to watch with the hydraulics is to make sure that the oil in
the cylinder is of the right viscosity. My machine kept breaking blades
until I discovered that the bowslide was falling too quickly because the
oil wasn't viscous enough. It needs ISO 150 oil.
> I'm now struggling with the coolant pump. As previously stated it is a
> piston pump driven by an eccentric on the end of the ''crankshaft.'' I
> machined up a bit of threaded bar to drive the piston from the eccentric and
> now when it pumps it tries to rival Niagara Falls and swamps the delivery
> cup and flex pipe. There must be a mechanism to regulate flow - it's not in
> the delivery system because that is intact, so I'm thinking that there must
> have been a mechanism to regulate piston travel?
I've been thinking about your question today and the only way I can see
to vary piston travel is to vary the eccentricity of the cam. The piston
travel will be the same even if you change the length of the piston or
connecting rod. Is there any way of changing the eccentricity of the cam?
If not, the "Niagara Falls" situation may be the way it's intended to
operate. But it's difficult to judge without seeing it.
> Is anyone familiar with my old Wisksteed saw (weighs about 1/2ton) maybe has
> one lying around or knows of any machine shops or suppliers that would be
> happy for me to come along and take a look?
I'm intimately familiar with the Qualters & Smith hacksaw, but not with
the Wicksteed. Is there any trace of the Wicksteed company to be found
online? I found out that Qualters & Smith had become Birkett Cutmaster,
and they sent me a very useful manual for my saw.
There were also at least three different Wicksteed hacksaws produced.
Early machines had the front end supported on two legs. Later machines
had a rounded front end. And the latest machines I've seen had a very
angular appearance. What cutting capacity is your machine?
I did save a large number of pictures of power hacksaws while I was
looking for one. I don't think they'll show the part you're interested
in clearly, but if you want them, just let me know.
Best wishes,
Chris
The Wicksteed pump is a very elaborate affair. Two pistons, two eccentrics,
a large rotary valve block, relief valves calabrated bleeds etc. A manual
control that varies the speed the blade drops and a control knob, with
''drop, idle, lift and work'' functions. It's a fine bit of kit, these saws
must have been very expensive in their day compared to the modern bandsaws
and circular/chop saws.
>
> The Qualters & Smith also has a two-speed motor, which is why the motor is
> huge. I'm not sure if the Wicksteed motor is the same.
My Wicksteed has a two speed gearbox, fast and slow (not surprisingly :-) )
>
> One thing to watch with the hydraulics is to make sure that the oil in the
> cylinder is of the right viscosity. My machine kept breaking blades until
> I discovered that the bowslide was falling too quickly because the oil
> wasn't viscous enough. It needs ISO 150 oil.
The lid for the hydraulic tank says to use light hydraulic oil, so I've used
some oil designed for digger hydraulics which seems fine so far. I notice
that with mine the blade only drops when the machine is running, if you
switch to ''work'' with it stopped the blade stays raised.
>
>> I'm now struggling with the coolant pump. As previously stated it is a
>> piston pump driven by an eccentric on the end of the ''crankshaft.'' I
>> machined up a bit of threaded bar to drive the piston from the eccentric
>> and now when it pumps it tries to rival Niagara Falls and swamps the
>> delivery cup and flex pipe. There must be a mechanism to regulate flow -
>> it's not in the delivery system because that is intact, so I'm thinking
>> that there must have been a mechanism to regulate piston travel?
>
> I've been thinking about your question today and the only way I can see to
> vary piston travel is to vary the eccentricity of the cam. The piston
> travel will be the same even if you change the length of the piston or
> connecting rod. Is there any way of changing the eccentricity of the cam?
There doesn't seem to be. I'm wondering if there was a linkage something
akin to the Stevenson linkage used for steam engine valves, travel could
then be varied. I'm sure I could probably invent something but I'd prefer to
replicate Wicksteed's design if possible - just for originality.
>
> If not, the "Niagara Falls" situation may be the way it's intended to
> operate. But it's difficult to judge without seeing it.
>
>> Is anyone familiar with my old Wisksteed saw (weighs about 1/2ton) maybe
>> has one lying around or knows of any machine shops or suppliers that
>> would be happy for me to come along and take a look?
>
> I'm intimately familiar with the Qualters & Smith hacksaw, but not with
> the Wicksteed. Is there any trace of the Wicksteed company to be found
> online? I found out that Qualters & Smith had become Birkett Cutmaster,
> and they sent me a very useful manual for my saw.
>
> There were also at least three different Wicksteed hacksaws produced.
> Early machines had the front end supported on two legs. Later machines had
> a rounded front end. And the latest machines I've seen had a very angular
> appearance. What cutting capacity is your machine?
>
> I did save a large number of pictures of power hacksaws while I was
> looking for one. I don't think they'll show the part you're interested in
> clearly, but if you want them, just let me know.
I've been looking all over the net and google images, I've not been
successful finding an image. If I get a moment tomorrow I'll post a few
pictures for you to look at. It's the design with front legs, I'm not sure
what the cutting capacity is - that would be the length of stroke as opposed
to the length of blade?
Julian.
http://photobucket.com/Wicksteed_hacksaw
It looks like the vice opens up to about 8'' so I'm guessing that is the
machine's capacity.
I'm particularly interested in comments regarding the coolant pump
arrangement. I made a link from the eccentric to the piston with some
threaded bar. Coolant delivery is far too much such that it floods the
delivery upper chamber and cup and knocks the upturned valve cup off it's
seat. Ideally I need to look at an original machine to see Wicksteed's
arangement and how delivery was controlled.
Cheers Julian.
>
> I'm particularly interested in comments regarding the coolant pump
> arrangement. I made a link from the eccentric to the piston with some
> threaded bar. Coolant delivery is far too much such that it floods the
> delivery upper chamber and cup and knocks the upturned valve cup off it's
> seat. Ideally I need to look at an original machine to see Wicksteed's
> arangement and how delivery was controlled.
>
I haven't seen one of these before (mine is a much smaller rapidor) but the
angled pushrod 'looks' all wrong. Is there an anchor point at the same height
as the eccentric but further along the machine ? Maybe the eccentric should
move a roughly horizontal bar, and the pushrod couple to it vertically. So the
pushrod movement would be reduced in proportion to the coupling point's
position on that bar.
-adrian
I know what you mean, but I'm not sure because the pump piston bore is
angled towards the eccentric - If the pushrod was vertical it would foul on
the piston internally. Thanks for the thought though.
At the moment I'm working on the manufacture of a pushrod with a ''pogo
stick'' portion in the middle - with a suitable spring I'm of the opinion
that I can remove some of the travel from the piston.
Julian.
Yes, it's the biggest piece of round stock that you can get in the vice
(you can usually cut a larger piece of round stock than rectangular).
> I'm particularly interested in comments regarding the coolant pump
> arrangement. I made a link from the eccentric to the piston with some
> threaded bar. Coolant delivery is far too much such that it floods the
> delivery upper chamber and cup and knocks the upturned valve cup off it's
> seat. Ideally I need to look at an original machine to see Wicksteed's
> arangement and how delivery was controlled.
As far as I can tell from the pictures I have, your coolant delivery
system, including the cups, is original. I presume the cups are intended
to even out the flow, so that the coolant isn't supplied in a series of
squirts.
In all but one of the pictures I have, the pump connecting rod is
missing. Which suggests that perhaps it wasn't the best part of the
design. But I've got one picture showing the connecting rod, and it
looks like you've got it pretty much right. Here's the picture:
http://www.mythic-beasts.com/~cdt22/wicksteed.jpg
Best wishes,
Chris
Incidentally, the two-speed 1 3/4 hp motor on my saw is even bigger than
that. It's all relative :-).
Chris
> http://www.mythic-beasts.com/~cdt22/wicksteed.jpg
Looking at that picture more closely I notice what look like tiny oil
pipes on the bowslide. Presumably there's an oil pump somewhere in the
machine?
Chris
That picture of yours either shows the ''posh'' version of my model or maybe
a slightly later one, it seems to have an ''autolube'' system similar to a
truck chassis. My saw just has oil holes for an oil can all with nice spring
loaded lids.
Thanks for the picture, it's certainly the best one that I've seen so far on
the www and shows the coolant pump arrangement up well.
> As far as I can tell from the pictures I have, your coolant delivery
> system, including the cups, is original. I presume the cups are intended
> to even out the flow, so that the coolant isn't supplied in a series of
> squirts.
Yes, I'm sure it is original, there's nothing to suggest that anyone has
messed with it. The cups must be to even out the flow, however the lower cup
is on a flexible mount so you can angle the thing in whatever direction you
desire - thus giving the flex delivery pipe an easier time!
I'll let you know how I get on with it.
Cheers Julian.
> I'll let you know how I get on with it.
>
I modified the pushrod to incorporate a spring link:
http://s251.photobucket.com/albums/gg291/Julian100_01/?action=view¤t=Img0296.jpg
It seems to work fine now. When the pump is priming itself the spring hardly
deflects and full piston travel ensures rapid priming. When coolant reaches
the delivery NRV at the top of the pipe pressure rises and the spring
deflects by about 1cm thus reducing piston stroke. Now I get a good coolant
flow and the little cups don't overflow.
When I'm happy with the design I'll probably loose that cheap galv Screwfix
threaded bar and use something that makes it look a little less codged
together!
I'd still love to take a look at the genuine Wicksteed arrangement though -
maybe I've improved upon the design?
Julian.
Are they just holes, or do the openings go through to a reservoir? My
saw has a hollow bowslide which forms a reservoir holding a couple of
pints of oil. I didn't discover the reservoir until I got a manual.
Probably the Wicksteed is different, but it's just a thought.
Chris
It looks like you've come up with a perfectly functional solution. Just
one more thought, though: is there any chance there was a porous element
of some kind in the top cup, maybe a sponge or a mass of metal wool or
something, to smooth out the flow?
Best wishes,
Chris
>>
>
>I modified the pushrod to incorporate a spring link:
>
>http://s251.photobucket.com/albums/gg291/Julian100_01/?action=view¤t=Img0296.jpg
>
I would suggest skimming the tramp oil off the top of the suds in there before
too long.
regards
Mark Rand
RTFM
Dare I ask why? I thought it made the surface of the coolant look rather
pretty :-)
Julian.
The flow is smooth now, (well enough as makes no odds) I'll see if I can do
a little video of it working this weekend if I find a minute.
Julian.
You could well be correct, the thought hadn't occurred, I'll have a good
look, cheers.
Julian.
Just realised I made a mistake here. My hacksaw cuts on the return
stroke and lifts on the forward stroke. Not sure why I remembered wrong,
but I thought I'd correct myself, even if it's a month or so late.
Best wishes,
Chris
I've just replied to another chap with a mechanical saw. My Wicksteed cuts
on the push stroke. On the return stroke the blade is lifted by the
hydraulics, trying to make it cut on the return would fail. As far as I can
remember the saws in the metalwork classroom (when I was as school) all cut
on the push. (could have memory failure though)
Thanks for the reply though.
Julian.
It sounds like the big-end is knocking on the video, it must be a
perculiarity of the phone microphone because it doesn't sound half as bad in
the flesh. It's in top speed, the blade has become a little blunt now
because I've done dozens of cuts with it.
One of our collies comes to have a look towards the end - apologies!
http://www.youtube.com/watch?v=4OAkfQSKwls
Julian.
that's an impressively crappy quality video, gotta say :)
Saw's going well though.
--
Austin Shackles. www.ddol-las.net my opinions are just that
Travel The Galaxy! Meet Fascinating Life Forms...
------------------------------------------------\
>> http://www.schlockmercenary.com/ << \ ...and Kill them.
a webcartoon by Howard Tayler; I like it, maybe you will too!
I especially crapified it just for you! It's done with a £60 mobile phone
from Argos, and a lens that gets covered in dust from my overalls pocket.
:-)
>
> Saw's going well though.
Yes it's not bad at all, essentially saved from the tip - what a wasteful
society we live in today. I bet a small workshop in Pakistan or India would
be absolutely delighted to own a machine like this and use it everyday....
Julian.
>
>Yes it's not bad at all, essentially saved from the tip - what a wasteful
>society we live in today. I bet a small workshop in Pakistan or India would
>be absolutely delighted to own a machine like this and use it everyday....
>
yeah. I'd have one but it'd hardly get used, really, as I don't do much of
that kind of cutting. Plasma cutter is the next thing on my list, when I
can find a cheap one.
> I've just replied to another chap with a mechanical saw. My Wicksteed cuts
> on the push stroke. On the return stroke the blade is lifted by the
> hydraulics, trying to make it cut on the return would fail. As far as I can
> remember the saws in the metalwork classroom (when I was as school) all cut
> on the push. (could have memory failure though)
The funny thing is, I thought the same. But when I was working on my
saw, I noticed that the blade cuts on the draw stroke. So I checked the
manual in case I'd put the blade in the wrong way round, and no, the
manual confirms that it should cut on the draw stroke.
So it seems there's variation between manufacturers.
Best wishes,
Chris
Mine makes the same knocking noise. I eventually tracked the noise down
to the slight lift which is given by the hydraulics once per cycle
(during the "push" stroke on a Qualters & Smith, or the "draw" stroke on
the Wicksteed, it would seem). I don't think it's anything to worry about.
Chris