Complete Propeller range pictorial database

[Hugz]

What is this prop off? A forty? Unpainted so early.

[Charles uk]

During our researches into the Seagull overview history, the other Charles interviewed several ex staff members who provided him with an approximate date of when Seagull closed the polishing shop, from memory sometime in the late 50s rings a bell. It was said that there were up to 5 men working in there, polishing all the lower units & props, the story went, that to save the considerable expense of this department, polishing stopped & painting started.
I have Cloverleafs with paint & without so it was probably some time late in their production run.
As Jon's rightly says Choppers were painted which would make them post Cloverleaf, but they have the thin silver paint finish not the thicker silver of the Hydrofans, supporting the pre Hydrofan school of thought.

Water inlet slots were just another one of Seagulls cost savings, probably coming when the gravity diecast moulds reached then end of their usefull working life, casting slots costs way less than the fixture that holds & rotates the lower unit & the time it takes to drill clean & up all those holes.

[Hugz]

My two blade chopper is unpainted.

[Nudge]

I can still send out the protractor thing to others and do simple cad stuff (2D)
The only camera I have in on my phone (it is better than nothing) I have posted all of the props that I have at the start of the thread but Im more than happy help where I can. Your all more than welcome to send your props to me...... If I get enough I will get a better camera!!!

The 4 blade clover that I have is painted but it may not be original!

[headdownarseup]

Hugz

What diameter is your 2 blade "weedfree". By the looks it's about 8 1/2" thereabouts i'd say. It could be, might be, possibly is for a 40.
I wonder if this might be regarded as some kind of "trolling prop". Maybe, maybe not...

Any way, nice to see another that some of us have never seen before.
Any markings on it?

Jon

[Nudge]

What will that 2 blade prop fit on? if it is a 102 prop then it wont fit on a 100 or 40 box will it? Once that is worked out then it is a case of try it on a 40 and see if it can drive it!

[Keith.P]

I wouldn't think that the two blade prop is even for a seagull.
looking at the prop, it has a steel insert in the centre, with a slot cut in the aluminium for a prop spring, but no slot in the steel insert, as you can see the spring has spun around in the past and will probably keep doing so.
A look at the other side may help.

[Hugz]

I wouldn't think that the two blade prop is even for a seagull.

I think you are on the money Keith.

I thought all seagull prop shafts are 1/2 inch?

Back

Internal shaft diameter

[Charles uk]

This is roughly what we were proposing as a template for taking the pictures.

The picture was only taken from 3 foot above the prop, so a prop that is a fraction under 9" appears a fraction bigger than 9", I'll have to try 6 foot above to see if it reads closer.

There will also be a label in one of the corners giving all the details like, part number, whether available new, diameter, pitch if known, gear ratio, models used on & approximate years of use, when we can find a volunteer who wants to become the resident Seagull prop expert.

If anyone has any bright ideas on how we could improve the direction we're heading in, please don't hesitate to let us know!

[headdownarseup]

I think for starters, a good series of clear pictures is a good way to go. Perhaps even a side view showing the pitch of the blades. Maybe easier just to show the gearbox with the prop attached rather than the gear ratio. Often people refer to pictures a lot easier than seeing numbers. Keep it really simple otherwise we'll get all sorts of questions about "are you sure this prop fits with this gearbox" and so on. Pictures tell more than words.

I will say one thing though which might cause a disturbance. I've noticed that even though a readily available prop in second hand form doesn't always conform to the same dimensions as what we're describing here. More than likely over years of use props end up getting dinged and chipped and have probably had some material filed away to bring them back to some sort of useable condition. Just saying cos i've got a few old ones that are not quite the full shilling shall we say. Something to be aware of.

Jon

[Charles uk]

Three or four high resolution pictures times 30 or 40 would take up a lot of room with the possibility of an attached cost for John, if you look at the part number you will note there is a lot of data contained in it & no confusion from 2 people calling the same prop different names & we can still call them by their family names.

Just like the serial number on any Seagull, it's very easy with very little research for any owner to learn what he has or should have, your 102 data base when finished, will provide a clear picture of what anyone's 102 should comprise of & look like from 1942 until 1994.

A side view is probably not the best way to illustrate & compare pitch as the varying diameters throw confusion into the picture, the intention is that the coordinator will be provided with the pitch, measured by someone with the necessary equipment & understanding or taken from the Seagull technical data sheets if available.
It's only the newbies that don't know the ratio of their lower units, not rocket science really as there are only 5 possibilities since 1942.

The plan is that the coordinator picks the best picture for the data base, many of these will be pics of new props as there a quite a lot of new ones about, there are good examples of all of the swept back family, the bow tie will be the hardest family to find perfect examples of, & there is almost a complete collection of new examples for the hydrofan & weedfree family's.
.

[Buzzook]

To illustrate the pitch it might make sense to use a builder's 'combination square' - the type that has a lock nut so that the return arm can be slid along it, such that if it's slid all the way to the end, it forms a 90 degree angle.

Or perhaps use a larger version of the magnetic triangle welders use when plumbing up vertical pieces?

If this was sat on the flat bench surface on the paper with the 360 deg grid on it, and then gently pushed against the edge of the prop, you could then 'read off' the accurate diameter (so it wouldn't matter what difference the height of the camera made) and if you did the same thing with the prop lying against the edge of the bench, with a white card behind it for clarity, and took the photo along the surface of the bench (ie horizontal view rather than vertical) with the square up against the edge of the prop again, you could read off the thickness of the prop. ie pitch.

Then we'd only need the photo of the prop with a 'measurement ruler' superimposed so that the ruler showed the *actual* measurement, rather than having the issue of the height of the camera making this problematic.

What I'm saying is - use the 360deg diagram to *determine* the diameter and pitch, but only supply the pics with a blank background. The artist then adds the *ruler*, as in the last pic (bit rough, but you get the idea).

[Rob Ripley]

I remember many years ago I was curious about the differences in props. I did calculate the working area of a few Seagull props .... lost the data some time ago. what did interest me at the time was the similarity of the pitch. So I laid a sliding bevel on a C100 prop and a 40+ prop.
Century 100 5 blade, 230mm dia = 147/33 degrees, Forty Plus 4 blade, 220mm dia = 147/33 degrees !
I wonder if the same angle has something to do with the casting mould ?[attachment=2]DSCF4266.JPG[/attachment][attachment=2]DSCF4266.JPG[/attachment][attachment=2]DSCF4266.JPG[/attachment]

[headdownarseup]

I've used exactly the same principles to measure the pitch in pretty much every single prop i've got. It works well enough for me, and will continue to use this method. I don't need something that's SUPER ACCURATE for measurement purposes. Near enough is more than good enough.

I was told by several members on here this was the wrong way to do it.

I was only following this guy's recommendations and tips.
https://www.youtube.com/watch?v=Uzv_m_Gm1es

Jon

[Charles uk]

I would like to see something done about the propeller database thing that was talked about.


I agree with you seagull101
Perhaps we need to work out which propellors go with which gearboxes and motors.
As an idea, I wonder if a scanner could be used (for those that have them) to get the images, because better pictures would show up the prop details like the identification numbers.

I think I've moved your post for you Jacsplat.