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HandyAndy
18th September 2009, 07:31 PM
as most of you know i,m building on a tight budget so would like to ask your opinion on whether i should or should not fabricate my own propshaft for my Roadster from the donor propshaft?

it looks fairly easy to do but am i being too tight to buy one or is it not safe to fabricate one from the donor parts i have?

£100 approx for a new propshaft compared to £0 for a diy one, the money i could save would pay for other parts i still need but if its a safety issue then i,ll accept that ,

so your opinions/advice is welcomed & sought.

thanks
andy:)

londonsean69
18th September 2009, 08:21 PM
TBH it is what they advocated in the Champion book, and it is mentioned in the roadster.

It all depends how confident you are with your welding, and if you can get the right materials, although I am assuming the propshaft needs to be shortened (no donor)

You could always take it somewhere and have it checked afterwards, and maybe balanced.

If you are really worried, but intent on doing it, why not fit a safety loop? The yanks do it quite a lot on drag cars

http://home.fuse.net/fastmonte/DSSL4Gbodies.htm

I just googled "prop shaft safety loop" and that was the first thing to come up.


I'm sure someone will be along soon to say "its a dumb/crazy/stupid idea" but then again so is building a car from scratch:D

Sean

RAYLEE29
18th September 2009, 08:22 PM
Hi Andy,
I'm making my own, I was given a 2.0l pinto from a transit and it came with g/box and prop the best bit is the transit prop has servicable joints so im making my own also the transit spline is the same as for a type 9 and the rear flange fits my 7.5" sierra diff
I just have to decide whether to use the big tube or the small tube which has the centre bearing
just to say I've modified props before and never had any probs.
just make sure it runs true before final welding and that the joints line up with each other
Ray:)

HandyAndy
18th September 2009, 08:36 PM
cheers Sean/Ray,
so i,m not barking mad ???:D

as the donor prop i have has a center joint which obviously i don,t need to incorporate into the shortened version would i still need the coupling at the gearbox end?
would it be ok to have the splined end a "rigid end" & the diff end with the coupling thats already there? the reason i ask is this would make it alot easier to fabricate as someone has suggested to me to just use the splined end welded onto the main shaft once i get the dimensions spot on :confused:

i feel confident enough to make it run "true" & would also sleeve the join to ensure a strong welded section,
like you say it is mentioned in both books so folk must have done it in the past:cool: , its not just the fact that i,m a tight git :o

i like the idea of a safety loop, think thats a good idea regardless of a diy prop or commercially made one.

cheers
andy

dogwood
18th September 2009, 08:46 PM
I made my own propshaft as well.
Including the rubber donut at the front.

I was not entirly happy with it, thought I would change it later.
That was 3,000 miles ago.
Still going fine, think I'll keep it...:D

David

HandyAndy
18th September 2009, 08:55 PM
thanks Adrian,
the safety factor is my main concern, tho i wasn,t thinking of using the rubber ring as like you say it is rather large for the tunnel,
some fellow kit car owner has suggested that i cut the splined end off the current prop & friction fit it into the larger tube that has the diff flange & weld it up once all is true, tho if i still need a coupling at both ends i could cut/shut the two parts(pipe) & then sleeve the joint, hmmmmm:confused:

Dogwood...... do you have a photo of your installed prop please, pref showing the gearbox end & the joint you made to fabricate it please?

thanks
andy

Bonzo
18th September 2009, 08:56 PM
I'll be setting mine up in the lathe & welding it up ;)

That bloody rubber donut is a very tight fit in the tunnel though :eek:

Hoping to find an early model prop before I get to that stage.

Cheers for the tip Ray, I may very well be able to lay my hands on an early Transit propshaft :cool:

RAYLEE29
18th September 2009, 08:57 PM
I would say you need a joint or donut at the g/box end and a joint at the rear
Ray:)

dogwood
18th September 2009, 09:16 PM
Dogwood...... do you have a photo of your installed prop please, pref showing the gearbox end & the joint you made to fabricate it please?

thanks
andy

Sorry Andy mate.
Just checked, Thats one pic I ain't got.
If it ain't pissing hard tomorrow I'll get the car out and take one.

As for the joint, I cut the donut end off.
Then put it in the lathe to give me the shoulder to reweld the pipe back on.

Hope this little pic helps
http://i129.photobucket.com/albums/p212/muddypaws4x4/prop.jpg

David

frankie boy
18th September 2009, 09:31 PM
HI
I made my own prop. It has a UJ a each end. Having coverd over 4000 miles and driven the car hard on track days im happy with its performance.

HandyAndy
18th September 2009, 09:32 PM
thanks David, yes that diagram does help, yes please to a pic as long as you don,t get wet :eek:

i,ll give it a go tomorrow, if it works then great as my wallet can breathe a sigh of relief for a little longer:o :D

thanks everyone for your input, much appreciated.

cheers
andy

dogwood
18th September 2009, 09:38 PM
Andy.
Can you send me a PM tomorrow to remind me.
Coz I'm bound to forget.

Yea, Yea...Alright so I've had a sherbert or two ok...:rolleyes:

David

HandyAndy
18th September 2009, 09:41 PM
:D no prob, & thanks :cool:

andy

flyerncle
18th September 2009, 10:04 PM
Place in Team Valley can balance it for you !

Land Locked
18th September 2009, 11:16 PM
For those looking for a way to lose the huge rubber "do-nut":

I put a gearbox from a sierra into my old cortina many many moons ago. Found the cortina yoke didn't fit the sierra box, so went back to the scrappy with the box and raided his propshaft collection. Found that the yoke from a hilman vogue fitted the sierra box in terms of the splines, just needed to be shortened by about an inch. Even the UJ's matched.

Back to the original question, if you get it lined up properly and your welding is good there should be no problem except possibly/probably balancing.

les g
19th September 2009, 10:34 AM
Andy
100% agree with all these guys
a flexible joint at both ends is a must and diy props are achievable
you just got to weld it true
and an old trick for when its on the car
if you have a slight vibration put a jubilee clip around the shaft and run it .if no better rotate it slightly etc etc until the vibration goes i have seen up to three jubilee clips used to smooth out a vibration :eek:
cheers les g

PS. it wasn,t my welding LOL :D

Neil P
19th September 2009, 11:08 AM
I made mine, it's fine. Rubber donut fits easy in a chassis made for an MT75 'box.

Neil

londonsean69
19th September 2009, 11:44 AM
I made mine, it's fine. Rubber donut fits easy in a chassis made for an MT75 'box.

Neil

Good - because that's what I'm planning on using.

Is there plenty of room for brake and fule lines, plus the leccy??

Sean

dogwood
19th September 2009, 06:11 PM
Hi Andy
Pic's as requested....

http://i129.photobucket.com/albums/p212/muddypaws4x4/agdeseptjpeg044.jpg

http://i129.photobucket.com/albums/p212/muddypaws4x4/agdeseptjpeg048.jpg

http://i129.photobucket.com/albums/p212/muddypaws4x4/agdeseptjpeg046.jpg


HTH David

Bonzo
19th September 2009, 07:46 PM
I can't believe that that Andy made you take the top off of your tunnel for that photo. :D

Looks a propper job David ( Excuse the cheap pun ) :o

Given me a clue to the way forward that's for shure ;) :)

HandyAndy
19th September 2009, 08:25 PM
thanks everyone, sorry for late reply but have had major internet connection problems, now sorted by ME :D me & computers don,t usually get on.

thanks for your help with the propshaft idea,

Les G i like the idea of the balance weights :cool:

David, thanks for the pics , they really help, clears a few things up.
i,m going to give it a go.

so thanks for all the input.

cheers
andy:)

AshG
20th September 2009, 12:53 AM
i was going to make my own shaft but my rubber donut thing is all split and falling appart. i am going to take the plunge and just buy a new custom one as i know it will have to take some serious abuse with me behind the wheel :D

dogwood
20th September 2009, 10:07 AM
I can't believe that that Andy made you take the top off of your tunnel for that photo. :D




Yea I know, pain ain't he...:D

Actualy it was not a bother, coz I wanted to check out the donun anyway.
( You ain't the only one that drives like a loon Ash :eek: )

Also part of my rebuild is to lower and move forward the handbreak leaver.
I wanted to see how easy it would be.

David

HandyAndy
20th September 2009, 12:13 PM
Yea I know, pain ain't he...:D


David

:o
tell you what !!!!!

i,ll buy the donuts at stoneleigh next year :p the ones with sugar on tho :D

thanks for the help

andy

HandyAndy
22nd September 2009, 09:10 PM
have you ever had an Eureka moment???????:D

well today whilst fabricating my own propshaft i was taking the center bearing housing apart to make the whole donor prop easier to handle,
after i,d got the center bearing apart i was left with the metal housing that holds the rubber vibration bush in place, so i took the rubber out of it & this now leaves me with in my opinion the perfect safety hoop for the prop,
i placed it onto the tranny tunnel tubes & raised it up on some 25mm sq tube that i had spare & lo & behold its a perfect fit, it allows the prop to rotate freely with enough space for slight movement at the gearbox end but in the event of prop failure it,ll stop the prop from coming thru the tunnel wall or dropping thru the floor, anyone see a prob using this?

cheers
andy:D

dogwood
22nd September 2009, 09:39 PM
Erm...... can you still get the prop shaft on and off??:eek:
Does the UJ go through it, or does it unbolt?

David

Bonzo
22nd September 2009, 10:07 PM
I try not to have Eureka moments.

Only ever had Two, both resulted in the arrival of my lads :D :D

Can't get a handle of your idea Andy :o

Afraid my brain is a bit FUBAR after the last week or so :eek:

HandyAndy
22nd September 2009, 10:17 PM
sorry had laptop prob, sorry for delay in reply,

i,ll try to explain a bit more clearly,
the hoop that originally held the center bearing on the donor prop, i,ve dismantled the bearing & removed the rubber internal bush, cut the bottom off the metal housing which now creates a safety hoop that i can bolt down onto the tranny tunnel frame,

maybe i should take a photo tomorrow? :o

andy

dogwood
22nd September 2009, 10:22 PM
sorry had laptop prob, sorry for delay in reply,

i,ll try to explain a bit more clearly,
the hoop that originally held the center bearing on the donor prop, i,ve dismantled the bearing & removed the rubber internal bush, cut the bottom off the metal housing which now creates a safety hoop that i can bolt down onto the tranny tunnel frame,

maybe i should take a photo tomorrow? :o

andy

Yea, think I got it now....
Had visions of you welding it all inplace then thinking.
How the fug am I going to get the prop on...:D :D :D

HandyAndy
22nd September 2009, 10:30 PM
Yea, think I got it now....
Had visions of you welding it all inplace then thinking.
How the fug am I going to get the prop on...

:D David ...... oh come on, i know i,m not the sharpest knife in the drawer but even i wouldn,t have done that :eek: ;) :D

as for the hoop, its a simple solution & its free, now you know i like lo-cost .

it works too.


andy

dogwood
22nd September 2009, 10:36 PM
David ...... oh come on, i know i,m not the sharpest knife in the drawer but even i wouldn,t have done that


andy


No offence.....:D
But......
I could defo imagine ME doing it though....:rolleyes:
I have been hit with the "Stupid stick" a few times

HandyAndy
22nd September 2009, 10:57 PM
non taken buddy :D

me & the stupid stick are good mates some days:o

andy

chriseyj
23rd September 2009, 03:25 PM
I think a prop safety loop is an excellent idea I saw an american guys locost blog a while ago and he had made a 2 piece loop from something like 3mm x 30mm strip.
Definatley could save damage to the car and your legs if the prop let go.
Am guessing the prop would just fall into the loop like a crude bearing if it snapped and help stop the prop whipping around.

Do you need at least 2 for it to be worthwhile? Could see that if it broke you would have both the diff and the engine ends spinning when rolling.

HandyAndy
23rd September 2009, 04:12 PM
i plan on putting the safety hoop just forward of the TT6 uprights as this then creates quite a good cage around the prop using the TT6 & TT4 uprights as additional structures to stop the prop coming thru the tunnel into the cockpit.

cheers
andy:)

flyerncle
23rd September 2009, 05:46 PM
10 Points Andy,bloody good idea 100% no cost too,if you are really concerned why not beef up that part of the tranny tunnel with a cross brace and a sheet of ally near the joint. I think I will do it now as that's where I am welding in now.

HandyAndy
23rd September 2009, 06:38 PM
:) cheers Paul,
its not very often i have a good idea but this is one that might be of use to others.
i can,t put any more braces into the tranny tunnel as i have fitted the floor now, but this safety hoop is defo going in. :o :cool:

andy

les g
23rd September 2009, 07:46 PM
Andy
that is a really good safety feature you are talking about
Jonneturbo lost his car to a fire when the prop failed and ripped out his
fuel lines in the tunnel
cheers les g

HandyAndy
23rd September 2009, 08:07 PM
cheers Les, credit should go to Londonsean69 for the idea in the first place, i,ve just taken it on & found a locost solution,
hope it is of use to others too.
i,m only using thin ali for my tunnel sides so any extra protection from a failing prop is welcomed, its even better knowing that it was free,
i mean after all i HAVE to keep my reputation for being a tight git :o :D

cheers
andy

dogwood
24th September 2009, 10:21 PM
Think I may be doing the same...
Just read this on LCB

"Another propshaft failure
Not mine,on a Seven that Dave Walker had on his rollers, went through the side panels and hit his leg at 120mph On page 98 in this months PPC.
That does it for me, definitely going to reinforce the tunnel."

http://www.locostbuilders.co.uk/viewthread.php?tid=122181


David

HandyAndy
24th September 2009, 10:31 PM
wow, that sounds nasty, i haven,t read the article so hope the guy is ok.
strange how this thread has discussed the very possibility of that happening, scary thought :eek:

lets hope it doesn,t happen to anyone else.

cheers
andy

chriseyj
25th September 2009, 08:35 AM
Blimey that sounds awful!, must pick up PPC when it comes out. In the mag Kevin Leapers superharged crossflow westield is coming on now, seems alot of effort for 150 bhp though.
I realised when I was talking wet earlier, 2 safety loops would be more appropriate for a BEC install like I'm thinking about where you'd have a very long 2 piece prop shaft with centre bearing or reverse box.

Bonzo
25th September 2009, 09:30 PM
After seeing that post. It has certainly made me have a quick re-think :eek:

Still giong to aler my own prop though. :)

Going to be putting something in the tunnel to prevent the prop coming through in the unlikely event of a prop failure ;)

I have some 2mm zintec sheet that I could put in the last bit of the tunnel sides.
The only concern I have about that idea is would the extra rigidity in that area have an adverse affect of the overall chassis flexibility !!?? :confused:

HandyAndy
25th September 2009, 09:37 PM
Ronnie, i,m no structural engineer but i think the way the full chassis is fabricated the transmission tunnel is part of the integrity of the chassis but by making the sides of the tunnel stronger with thicker material won,t affect the overall flexibilty, as the sides will purely act upon the frame of the tranny tunnel, in my opinion of course;)

cheers
andy
ps, its also creating a safe cell for the occupants of the car:cool:

spud69
25th September 2009, 09:59 PM
For my 2p worth, the prop is a critical part of the running gear and will greatly effect the handling and balance / feel of the car if its not correct.

My first prop was a cut down sierra prop with the balance wheel cut off the donut and welded very true, from what i thought. First test drive out, on my way to a pre-mot ;) and it nearly shook the car to bits and actually necked off one of the welds on the exhaust at 40mph.

Phoned Dunnig and Fairbank in Leeds, drove down and they made me one in two hours. Lovely bit of kit once fitted to the car absolutely transformed it, was so smooth it was like a different car. All for 95 squid;

Not worth trying to bodge in my humble opinion.

Andy

Coozer
25th September 2009, 10:47 PM
Having read the article in PPC and hearing of others letting go in the past I would recommend a new one. Mine was £110 from Dunning Fairbank and come registration on the bit were it says Transmission? tick NEW and show the receipt for the prop:)

http://i303.photobucket.com/albums/nn126/ridler123/General/P1010071.jpg

HandyAndy
25th September 2009, 10:59 PM
GULP , blimey those photos really do bring it home :eek: ,

hmmm, maybe i should get a proper job done with the prop, i mean if it was just me that got injured if it happened but the thought of hurting a passenger for the sake of £100 or so really makes me think.

thanks for the pics Coozer.

andy

Bonzo
26th September 2009, 09:43 AM
I couldn't agree with you more spud.
This is one job best left to those who know what they are doing ;)

That said, I personally feel that I have the right equipment, training & skill to carry out the task of altering the propshaft.

If I alter my prop & am not happy with the result or quality of the drive, trust me i'll know if things are not right.
It'll be straight on the phone to order one :)

My concerns are, what to do to assist safety in the event of prop failure !!??

I am minded at the moment to do the following.

Cover the sides of the transmission tunnel ( From TT4 to SB4 ) in some 2mm zintec sheet that I have & just begging to be used for the job .

Fabricate some 3mm strip steel safety hoops to place arround the prop.

My legs don't work too well at the best of times, I would still like to keep them, there the only ones I have got :D


Interesting to note looking at the photograps of the failed prop. It was a big time torque failure of the material.
Just goes to show that a good quality weld will never let go first !!??







For my 2p worth, the prop is a critical part of the running gear and will greatly effect the handling and balance / feel of the car if its not correct.

My first prop was a cut down sierra prop with the balance wheel cut off the donut and welded very true, from what i thought. First test drive out, on my way to a pre-mot ;) and it nearly shook the car to bits and actually necked off one of the welds on the exhaust at 40mph.

Phoned Dunnig and Fairbank in Leeds, drove down and they made me one in two hours. Lovely bit of kit once fitted to the car absolutely transformed it, was so smooth it was like a different car. All for 95 squid;

Not worth trying to bodge in my humble opinion.

Andy

Coozer
26th September 2009, 11:14 PM
Its a good idea to combine some loops into the tunnel when you fabby your chassis.

On my old Striker with a bike engine and two piece prop I bolted in a loop around the mid joint out of 5mm steel plate and thinking back I reckon more would have been better.

More chassis triangular members and hoops will add safety and strengthen the chassis.

Steve

7ishNZ
27th September 2009, 12:53 AM
In New Zealand the rules say we must have a safety hoop at each universal made from minimum 50x5mm steel.
I would not attempt to make my own driveshaft.. the alignment and balance is critical, and the consequences of a failure are not worth the few quid you might save.
You guys are a bit lucky in the UK regarding prop shafts... I was quoted NZ$1900 for a 1.4 meter long 2 piece shaft.. that's about 840 quid!!!

jasongray5
27th September 2009, 11:52 PM
In New Zealand the rules say we must have a safety hoop at each universal made from minimum 50x5mm steel.
I would not attempt to make my own driveshaft.. the alignment and balance is critical, and the consequences of a failure are not worth the few quid you might save.
You guys are a bit lucky in the UK regarding prop shafts... I was quoted NZ$1900 for a 1.4 meter long 2 piece shaft.. that's about 840 quid!!!

Surely it would be cheaper to get one made here and sent over to you then??:confused:

7ishNZ
28th September 2009, 06:09 AM
Yes.. I was quoted 160 pounds for 3 day post to NZ. That's what I will be doing.

Trophy Blue
24th October 2009, 09:17 PM
I'll be setting mine up in the lathe & welding it up ;)

That bloody rubber donut is a very tight fit in the tunnel though :eek:

Hoping to find an early model prop before I get to that stage.

Cheers for the tip Ray, I may very well be able to lay my hands on an early Transit propshaft :cool:

Ronnie,

You can get the right end from a transit, capri, very early sierra or a cortina.

I made my prop as I only trust my own welding

Bonzo
24th October 2009, 09:37 PM
Ronnie,

You can get the right end from a transit, capri, very early sierra or a cortina.

I made my prop as I only trust my own welding

Thanks for that :)

I knew the early Sierra had the right joint but did not know about the other possibilitys :cool:

I'll be keeping my eyes peeled, unless I steal the one from my 1987 transit & stick the donut on that :D