turn buckles and tank straps

[Lynn Eades]

Here are some more differences between Canadian and British built carriers.
The top turn buckle is Canadian. it has bigger diameter ends where the pins go through. The threads are not the same as the british ones which have the shorter brass section. the British ones come in the two variations shown at the bottom. I have not identified the theads.
The tank straps vary in that some have spot welded ends and some have riveted ends. This may be due to earlier/ later production, or even a sub contractors choice.

[RichardT10829]

Excelent stuff Lynn.... i need to make some more floor T peice brackets for my straps as the ones in the hull are a shadow of their former self !

[Ben]

I need to make some too. I suspect that it's quite common that they rot out.

I think I'll make a program and get a load made on the cnc mill.

Ben

[Lynn Eades]

The originals were cast. Is the CNC mill the quick/ cheap way to do them?

[Ben]

I don't know? I'd need to see a good original to measure to be sure. I'd prefer them to be cast if that's what they were originally. Casting will probably be cheapest if there is a bulk quantity.

Ben

[Nigel Watson]

Lynn it is uncanny as today I received an item purchased from Ebay. A turnbuckle. It was designated RAF type AGS 141 ABC 15-20cwt 3.25". It looked and is very close to the carrier parts manual. So I googled it and came up with an aero company over here that had turnbuckles but not with the same AGS numbers.

I went back to the trusty parts manual and read the details more closely to find the detail CO1UC 105114 TurnBuckle - Fuel Tank Connections (UK No. MT15/ AGS-492 BCE). The company have thesebut they are not only very expensive but the body is parallel instead of being tapered slightly at each end. The BCE refers to the thread direction of the end-body-end.

The one I got from Ebay is almost exact. Incidently it was described as having been used on the Gloucester Gladiator around 1937! Why manufacture if there is one already being made?

So if anyone is successful in tracking down the Gadiator stores please let me have 3.

Nigel

[RichardT10829]

i have the correct dia brass bar to turn down buckles but would need one to copy. pretty easy to make methinks.....

[Ben]

I've got two straps both almost identical, ones British TL stamped (bottom) the other Canadian CTL stamped (top) they are both spot welded so i'm not sure when the change happend from riveting?

[RichardT10829]

iam guessing when welding technology moved on a bit or perhaps knowlege of welding ? i have located a turnbuckle which was in amongst my little bits so will start enquiring about making a run of them... i have some victorian brass stair rods which are the correct gauge to start from so will see about making some more......the eyes maybe a different kettle of fish for me but will see what i can come up with.

[Lynn Eades]

your straps are of the (later?) type. The turnbuckles I have posted go with the straps I was refering to. I have edited my incorrect post about the origin of the riveted verses spot welded variations.

[Ben]

Thanks Lynn

Once it arrives I'll look at making them. Shouldn't be an issue on the lathe at work. Richie perhaps we can pool our resource?

Ben

[RichardT10829]

yeah good idea like i say i have an early mk1 canadian type turnbuckle and lower section of strapping

[Lynn Eades]

I hadn't picked up on you having one.

[RichardT10829]

yeah just the one... i have popped it into a bath of diesel to free it up but it is something to use as a pattern i guess.

[Lynn Eades]

I have checked the threads.
Canadian turnbuckles use a 1/4 UNF thread
British turnbuckles use a 1/4 BSF thread

[Ron Pier]

Are you sure about the BA threads Lynn? I'm no engineer! But I would have thought the Brit equivalent would have been 1/4 BSF or BSW. 0BA is not far off 1/4" but more in use for instuments I think.


Ron

[Lynn Eades]

Your are correct! I took a short cut. I expected it to be BSF, but a BSF bolt wouldnt start in it so I tried the BA bolt and it run in fine. What I found after you pulled me up was that the end of the thread was damaged. After I fixed it the BA bolt was quite loose. Thanks Ron, Now I'm not sending anyone in the wrong direction.

[RichardT10829]

Originally Posted by Lynn Eades

The originals were cast. Is the CNC mill the quick/ cheap way to do them?

Lynn i have been pondering on this one i reckon casting is the best way.. you could cast the triangular base then drill it and slide the retaining bar through for the strap. then when its under tension it will be held in place ? dont know seems the easier way to me though

[Lynn Eades]

You'd better try again Rich. I don't follow what you're trying to tell me.
We are talking about the little square bracket that rivets to the floor with 4 rivets. It has a central lug that connects to the strap, with a pin. Your turn.

[Ben]

As soon as the one Lynn has lent me arrives I'll make a new pattern and get some cast.

Ben

[RichardT10829]

yes thats the bit..... i was refering to the comment if CNC or casting was the way forward for reproduction. so my thoughts were casting was the way forward.... however pending on what tools Ben has access too CNC may be the way forward ? dont know..... was just spit ballin

[kevin powles]

Ben,

I will post out your parcel next tuesday as have been really busy this week.

I need four of those turnbuckles, I have made four for the mortar carrier already, I purchased a set of 1/4" unf taps for the job, left and right hand thread. I can post the taps to you if you like.

I made them on a lathe which i think is better than casting them, take a look and tell me what you think, two are made two are original Canadian.

Kevin

[Ben]

Kevin

It's the strap bases that rivet to the floor I'd planned on casting but it may be a toss up about the turn buckles, I'll hold off until I see them. Yours look good, the originals have a cast look about them. I'd imagine that during the war that it would take less time to cast a batch of blanks then tap each end rather than turn them but who knows!!!

If you don't need them, then please post the taps.

Ben

[Leo Blekkenhorst]

Hi, Is it possible to get the dimensions of the turn buckle pieces?
I have to make some too for my MK1.
Thanks, Leo