harrier practive bomb - moving - lifting eye/or advice

[iainmaoileoin]

I have a harrier practice bomb  at home.  I need to get it to my bunker as a "gate guardian".   I have an LR and a trailer.

I live in the hills, my wee fergie cant lift the bomb on the buck rake.

My kubota digger will, but trying to get frame/chains to do a vertical lift is hard.  I did build a scaffold frame and and and...  nothing really works so far.

I see a lifting eye in the bomb - about 1+7/16 (37mm or so) using a very fine pitch thread - say 2mm or so.  I have no way to ID this thread to see if I can find a bolt that fits it.

If I could find a bolt to fit that I could weld up a lifting eye - or does anyone have an eye I could rent/buy/use etc etc.

Any advice is welcome.  Living remotely means that getting in a different lifter (say a fork lift truck) is very very expensive.

Clues?

Thanks in advance.

[john1950]

Main thing is not to get hurt moving it. I will have slings but am probably to far away.

[TJSB]

Difficult to understand the problem without photos, but I am guessing it is not too heavy. A collapsible engine hoist sounds like it may meet your requirements. You could lift it and back the rover under it perhaps if the ground won't allow pushing of engine hoist.

[iainmaoileoin]

has a picture of the 1000lb bomb.  It is full of concrete and does weigh in a hernia weight.

This photo has a lifting eye.  My bomb does not.  It has a 37mm (ish) with a 2mm pitch thread hole.  If I could find  a bolt/or lifting shackle then I would win.  At present I have the bomb in/on a scaffolding pole frame and have decent chains and certified shackels.  So I am trying to find somebody who knows the thread type or could suggest how I get the lifting eye.

 

[iainmaoileoin]

2 hours ago, john1950 said:

Main thing is not to get hurt moving it. I will have slings but am probably to far away.

I tried moving the beast with 5 ton slings wrapped around it - they just slipped ..... no matter when I fitted them.  Hence a move to scaffold poles and chains.  The poles are to provide places where I can attach the chains stop them slipping.  But thatt theory did not work too well either.

 

[ruxy]

1 hour ago, iainmaoileoin said:

has a picture of the 1000lb bomb.  It is full of concrete and does weigh in a hernia weight.

This photo has a lifting eye.  My bomb does not.  It has a 37mm (ish) with a 2mm pitch thread hole.  If I could find  a bolt/or lifting shackle then I would win.  At present I have the bomb in/on a scaffolding pole frame and have decent chains and certified shackels.  So I am trying to find somebody who knows the thread type or could suggest how I get the lifting eye.

 

You can get pour plastic stuff - similar to RTV , specially made to cast in unknown threads  - unscrew / pull it out then get to work with micrometer /ruler/pitch gauges.

[iainmaoileoin]

2 hours ago, ruxy said:

You can get pour plastic stuff - similar to RTV , specially made to cast in unknown threads  - unscrew / pull it out then get to work with micrometer /ruler/pitch gauges.

I have done that using polymorph - 60-70 degree  hot-water-melt plastic.

Two issues - the bottom of the threaded hole has no thread and opens out by a few mm, so the polymorph filled that gap and made it a devil of a job to get the threaded plug out!  If I cast again I need to put a wee wooden spacer in.

Anyway having done that the thread appears to be a 2mm pitch and the outside diameter is of the thread is 36.54 mm so is somewhere between 1 and 7/16ths but not quite 1 and 1/2 inches.

I took the size and the casting to a local "always finds what I need nut and bolt shop".  They just laughed.   Nope that aint Whitworth it aint metric and it aint UNC might be UNEF or UNF but we have nothing like that!  You dont want to know the price of a singe 1+1/2 bolt!  I cant order one on the grounds it might work!

I was going to 3d print some bolts to see if the pitch and Diameter is correct - but my poor wee mac does not have the power to finish a design of a 36.5 mm bolt!

Remember the thread is kind of rusty so getting into the depth of the thread is a bit messy.

[ruxy]

2mm pitch is what is to be expected on M14 (course)  , so quite fine on 36mm.  1000 kg is no big deal on a spl. eyebolt  .  Your best bet is to take what info. you have & a chunk of  40mm leadloy abt. 200mm long and give it to a centre-lathe turner to screwcut  (obviosly it would be best to get the bomb to him for sizing). 1 tonne mass on 36mm requires no fancy grade of steel ,  a oversize bolt of lowest grade would suffice.    Tommy-bar hole drilled suitable size to accept a lifting shackle.

[iainmaoileoin]

Thanks, that makes things simpler.

I had assumed I needed carbon++ and nickel and chrome alloy etc.  I will see if I can find anyone in Inverness who can cut that thread.  I am guessing that the thread is a UNC sort of thing.  For the 1" of depth will it matter much about the angle of thethread walls?

The only internet (not ebay) sales of 1.5inch bolts are over £100!  And they might not fit.

[ruxy]

I served a 6 year apprenticeship as a fitter & turner - it's just 2nd year (ord.)  City & Guilds /EITB craft level.  Search out the local tool-rooms etc.  The root may be flat or with radius - hardly matters , the crest could have radius that needs a chase , they should have a selection of internal threading tools with known angles.  You hardly need a check-nut  - but if you are prissy and prepared to pay additional  £.  Your local Technical College or EITB training place should be able to sort you out - possibly gratis  ?    Modern lathes have a Norton  'quick-change'  gearbox , no need to work out the gearing ratio   LoL

[Sean N]

Are you sure this is not metric? The dimensions you've given sound very close to M36 x 2.0 metric fine, allowing for a bit of measuring error on the diameter. Have you tried lifting equipment companies rather than fastener suppliers?

Having said that, to slinging it, it's difficult to visualise your situation without photos but can't you use webbing slings rather than chains or lifting from an eye? Choked round it, particularly with a double wrap, they should work and shouldn't slip.

If you don't have any webbing slings you should be able to buy a couple easily and very cheaply, and should be able to sling from the Kubota arm / jib (if it's the sort of mini slew I'm visualising) particularly if there's an inbuilt lift point on the bucket or arm.

[iainmaoileoin]

1 hour ago, Sean N said:

(1)Are you sure this is not metric? The dimensions you've given sound very close to M36 x 2.0 metric fine, allowing for a bit of measuring error on the diameter. Have you tried lifting equipment companies rather than fastener suppliers?

(2)Having said that, to slinging it, it's difficult to visualise your situation without photos but can't you use webbing slings rather than chains or lifting from an eye? Choked round it, particularly with a double wrap, they should work and shouldn't slip.

If you don't have any webbing slings you should be able to buy a couple easily and very cheaply, and should be able to sling from the Kubota arm / jib (if it's the sort of mini slew I'm visualising) particularly if there's an inbuilt lift point on the bucket or arm.

 

(1) No I am not sure, but this is old Harrier type practice bombs.  I assumed the UNC war-time stuff would continue to be  used in this kit.  Let me go cast again and see what comes out.  I did got to Reid nuts and bolts in Inverness.  Those guys have always been able to source 'strange' bits for me.  This time - looking at the plastic moulding the answer was 'nothing I have ever seen before' .  That immediatly removed me from Metric.  If they are not dear I will go order a 36 x 2 and see what happens.

(2) I started with webbing (ratchet straps for tie-down) and no matter what I did it just slipped.  I have subsequently seen pictures of 'professional' tie-down - they have loops that fit over the front and the rear and are ratcheted in tight.  Try as I may I just cant form anything like that (yet).   Not something I could find on e-bay!

I do have a lifting point on the digger, and better I have 1-2-20 tonne straps for towing other things - as I say I cant get them to grip on the bomb.  I guess that means I have not yet found the balance point.

Again - you have set me thinking on how to get a loop at the front - I need to go get my engineer involved (the wife!).

 

[Mk3iain]

It may help to open up an internet search to standard UK 1000lb bomb. I don't think they were aircraft specific and were held by the thousands everywhere there were aircraft using them. Such as Jaguars, Harriers and Vulcans etc....

It may help turn up something or some information.   It may be that it had an inventory mark for Wittering or Gutersloh but they are standard.

I have vivid memories of our unit (MRT) arming and assembling live retarded 1000lb bombs in Bruggen as punishment for hiding during exercises.... I was an avionics tech, go figure.

[Adrian Dwyer]

Not exactly what you need, but this is the blanking plug: pitch gauge in place!

[iainmaoileoin]

Adrian Dwyer: thanks, but on my bomb the central thread is not 50mm - much closer to 36mm.

However I have been told I can remove the two "square lugs" it may be they are the 50mm.

The 2mm guage helps a lot - I was measuring my pitch against a plastic mould.

 

All:  I have been told I need a "suspension lug No 43 Mk 1" to do the job.

 

Edited September 21 by iainmaoileoin
adding info

[Adrian Dwyer]

3 minutes ago, iainmaoileoin said:

Adrian Dwyer: thanks, but on my bomb the central thread is not 50mm - much closer to 36mm.

However I have been told I can remove the two "square lugs" it may be they are the 50mm.

The 2mm guage helps a lot - I was measuring my pitch against a plastic mould.

 

All:  I have been told I need a "suspension lug No 43 Mk 1" to do the job.

 

Good luck with it!  Do post pictures of the solution/work around you go for.

All the best.

A

[Sean N]

Ratchet straps wouldn't do it. I'm not sure if you're over-thinking it though? I was just thinking of some standard webbing straps for lifting - the sort with an eye at each end - this sort of thing, but longer, say 2m:

 

I was thinking that if you use two and choke them with a double wrap on the main part of the bomb where it is roughly parallel it would not slip:

I would think you would buy a pair of 2 - 3 metre 1 tonne straps for £20 - £30 online.

 

 

 

[Adrian Dwyer]

Royal Engineer 'sticks and strings' would use a Cat's Paw.

[Adrian Dwyer]

Cat's Paw

[Adrian Dwyer]

Variants: Chain or rope (or strop)

[Oh Five]

If the taper of the ends of the bomb are causing the slings to slip why not just use two or three short lengths of rope to keep them at the correct distance.  

Another option, cut two lengths of timber with curves to match the circumference of the bomb. Roll the bomb on top of them, so they are perpendicular to the centre line of the bomb. Use rope to keep the timbers at the same distance and from slipping off the ends. Straps or other ropes could be attached to the ends of the timber to enable lifting.

You might need a counter balance on your three point linkage.

If your Kubota is an excavator, not a tractor, then you could try using the digger bucket to drag the bomb to the trailer and then to roll it up ramps or planks onto the trailer.

Good luck

Dan

[Adrian Dwyer]

A few more options.  As I'm sure you know, if you are planning a horizontal lift and are concerned about the point of balance being close to the nose, consider using a spreader. 

Not, I know, your specific application but many images of WW2 bombs being hoisted show the half hitch/timber hitch combination.

 

All the best.  A

[iainmaoileoin]

14 hours ago, Oh Five said:

(1) If the taper of the ends of the bomb are causing the slings to slip why not just use two or three short lengths of rope to keep them at the correct distance. 

(2)Another option, cut two lengths of timber with curves to match the circumference of the bomb. Roll the bomb on top of them, so they are perpendicular to the centre line of the bomb. Use rope to keep the timbers at the same distance and from slipping off the ends. Straps or other ropes could be attached to the ends of the timber to enable lifting.

You might need a counter balance on your three point linkage.

(3)If your Kubota is an excavator, not a tractor, then you could try using the digger bucket to drag the bomb to the trailer and then to roll it up ramps or planks onto the trailer.

Good luck

Dan

Dan: Thanks for the inputs.

(1) yep the taper and the "no balance point" is the issue.  To get the lifting strength I am using chains and certified shackles.  The chain (metal on metal) slips - hence the use of a scaffolding frame under the bomb - but the balance is/was strill not correct.  The digger bucket is about 6" (trenching for cable) but even when that narrow it is hard to find centre.  Of course, when things slip the chain gets caught under the bomb/scaffold.....  So yes I will head out and see what I can do with some polyprop ropes!

(2) roll the bomb!  If only.  The bomb has 2 square lumps on it (to attach to the plane for the bomb release), so rolling gets messy.  The bomb is also in a field on my croft, so the ground is not hard.  You have no idea how far a 1000lb bomb sinks into peopl.  The whole shebang was on a pallet - but I dont have any pallet lifting kit -  When I use my wee fergie, the front wheels just come up off the ground!  I will head out today and try some of these ideas.

(3) that was where I started about 2 weeks ago.  Somehow everything just went wrong!!! 

Lots more to try.  I think  my initial mistake was to go for chains (strength) rather than ropes.

I will reset and try again.

[iainmaoileoin]

3 hours ago, Adrian Dwyer said:

A few more options.  As I'm sure you know, if you are planning a horizontal lift and are concerned about the point of balance being close to the nose, consider using a spreader. 

Not, I know, your specific application but many images of WW2 bombs being hoisted show the half hitch/timber hitch combination.

 

All the best.  A

Nice clues.  I am not a mechanical engineer - and something as simple as a spreader may make a difference.

Thanks for taking the time.

I will report back.

[Adrian Dwyer]

My earnest advice would be to take your time!

All the best.

A