Printable Version | Subscribe | Add to Favourites
New Topic New Reply
Author: Subject: Chopping and rejoining chassis
MK9R

posted on 21/1/10 at 01:36 PM Reply With Quote
Chopping and rejoining chassis

Any recommendations on how to rejoin the main chassis tubes if i cut the front section off between the engine and suspension pick up points?? Ideally i want to build the new front end up on the bench, then join it to the existing chassis (which is a completed car). Ideally would have been nice to slide an insert inside the tubes and push together and weld, but the angles chassis rails stop this option





Cheers Austen

RGB car number 9
www.austengreenway.co.uk
www.automatedtechnologygroup.co.uk
www.trackace.co.uk

View User's Profile E-Mail User Visit User's Homepage View All Posts By User U2U Member
blakep82

posted on 21/1/10 at 01:42 PM Reply With Quote
isn't it best to renew whole tubes instead?
cutiing and joining tubes is like cut and shut isn't it?





________________________

IVA manual link http://www.businesslink.gov.uk/bdotg/action/detail?type=RESOURCES&itemId=1081997083

don't write OT on a new thread title, you're creating the topic, everything you write is very much ON topic!

View User's Profile View All Posts By User U2U Member
MK9R

posted on 21/1/10 at 01:50 PM Reply With Quote
quote:
Originally posted by blakep82
isn't it best to renew whole tubes instead?
cutiing and joining tubes is like cut and shut isn't it?


yes it would be, but that would be a full strip back to the bulkhead, simply not an option





Cheers Austen

RGB car number 9
www.austengreenway.co.uk
www.automatedtechnologygroup.co.uk
www.trackace.co.uk

View User's Profile E-Mail User Visit User's Homepage View All Posts By User U2U Member
russbost

posted on 21/1/10 at 02:02 PM Reply With Quote
Absolutely no problem with joining tubes providing they are welded properly. Obviously the usual measure twice cut once applies, but due to the fact that you're workoing in 3 dimensions with (presumably) 4 tubes you will probably need to juggle it all about a bit to get everything aligned. I would suggest clamping some tubes along the sides of each joint to ensure all is square - you may well find a bit of tweaking of new &/or old sections is required.

If you are concerned about the strength of the finished item then just add a brace across each joint.





I no longer run Furore Products or Furore Cars Ltd, but would still highly recommend them for Acewell dashes, projector headlights, dominator headlights, indicators, mirrors etc, best prices in the UK! Take a look at http://www.furoreproducts.co.uk/ or find more parts on Ebay, user names furoreltd & furoreproducts, discounts available for LCB users.
Don't forget Stainless Steel Braided brake hoses, made to your exact requirements in any of around 16 colours. http://shop.ebay.co.uk/furoreproducts/m.html?_dmd=1&_ipg=50&_sop=12&_rdc=1

NOTE:This user is registered as a LocostBuilders trader and may offer commercial services to other users
View User's Profile Visit User's Homepage View All Posts By User U2U Member
A1

posted on 21/1/10 at 02:18 PM Reply With Quote
Id maybe be tempted to weld the tubes then add a bit of bracing and weld that up too. got any pics of the bit in question?
View User's Profile View All Posts By User U2U Member
MK9R

posted on 21/1/10 at 02:27 PM Reply With Quote
quote:
Originally posted by A1
Id maybe be tempted to weld the tubes then add a bit of bracing and weld that up too. got any pics of the bit in question?


Its the full front end, so main tubes got to be cut and rejoined





Cheers Austen

RGB car number 9
www.austengreenway.co.uk
www.automatedtechnologygroup.co.uk
www.trackace.co.uk

View User's Profile E-Mail User Visit User's Homepage View All Posts By User U2U Member
Agriv8

posted on 21/1/10 at 02:27 PM Reply With Quote
Id be tempted to sleve weld an internal tube then drill through and a spot of puddle weld on existing rails.

regards

Agriv8





Taller than your average Guy !
Management is like a tree of monkeys. - Those at the top look down and see a tree full of smiling faces. BUT Those at the bottom look up and see a tree full of a*seholes .............


View User's Profile View All Posts By User U2U Member
Daddylonglegs

posted on 21/1/10 at 03:34 PM Reply With Quote
quote:
Originally posted by Agriv8
Id be tempted to sleve weld an internal tube then drill through and a spot of puddle weld on existing rails.

regards

Agriv8


My thoughts exactly. Would give it much more strength than just joining/bracing the tubes externally.





It looks like the Midget is winning at the moment......

View User's Profile View All Posts By User U2U Member
MK9R

posted on 21/1/10 at 03:51 PM Reply With Quote
quote:
Originally posted by Daddylonglegs
quote:
Originally posted by Agriv8
Id be tempted to sleve weld an internal tube then drill through and a spot of puddle weld on existing rails.

regards

Agriv8


My thoughts exactly. Would give it much more strength than just joining/bracing the tubes externally.


Can't do that as chassis rails are angle inwards and want to build the new front end up on the bench so i can get it nice and straight and welded all round





Cheers Austen

RGB car number 9
www.austengreenway.co.uk
www.automatedtechnologygroup.co.uk
www.trackace.co.uk

View User's Profile E-Mail User Visit User's Homepage View All Posts By User U2U Member
scootz

posted on 21/1/10 at 05:33 PM Reply With Quote
Bizarre!

I was thinking this very thing myself this morning - no need to the ask the question now!







It's Evolution Baby!

View User's Profile View All Posts By User U2U Member
lsdweb

posted on 21/1/10 at 06:12 PM Reply With Quote
There's some photos on what 'we' did to my Westfield here

Wyn






View User's Profile View All Posts By User U2U Member
craig1410

posted on 21/1/10 at 06:15 PM Reply With Quote
Can't you create some heavy duty plates (eg 6mm steel) and then bolt on the entire front end? Obviously use high tensile (10.9 or 12.9) bolts like you would with a roll bar.

I would think you would need something like 2 M10 or M12 bolts per plate with perhaps 6 plates. (4 corners plus 1 either side of tunnel). Ideally the plates would have flanges to carry the shearing loads rather than rely on the bolts themselves.

I would be a bit concerned about cutting and welding in a line right across the car and would prefer to go the bolt-on route. Each section can be made structurally independent and with a defined interface between the two sections.

Could also prove very convenient when removing the engine and gearbox.

Thoughts?
Craig.

View User's Profile Visit User's Homepage View All Posts By User U2U Member
craig1410

posted on 21/1/10 at 06:17 PM Reply With Quote
quote:
Originally posted by lsdweb
There's some photos on what 'we' did to my Westfield here

Wyn


That looks fine because the upper and lower tubes don't stop at the same longitudinal plane.

View User's Profile Visit User's Homepage View All Posts By User U2U Member
Angel Acevedo

posted on 22/1/10 at 05:11 AM Reply With Quote
Reinforcing Grafts

I would use gussets on the union, with a "U" section made to cover 3 sides, or an "L" for two sides; these with tube or 16 Ga steel, or make Triangular Gussets from the Pipe size you´re using.
Just cut a 45º onthe end of the pipe, then another 180º apart, Grind to fit on the inside, weld, done..
HTH
AA





Beware of what you wish.. for it may come true....

View User's Profile E-Mail User Visit User's Homepage View All Posts By User U2U Member
907

posted on 22/1/10 at 09:07 AM Reply With Quote
If I wanted to butt weld box section and be 100% sure of the weld strength and penetration I would use the backing strip technique.

As you can't buy it I would make up a length of 22mm box.
Grind through two opposite corners of 25mm box to cut it into angle and weld it back together to form 22mm.
Clean off the welds and cut into short lengths and insert into the 25mm half way and tack.

In the case of your chassis, because these are short you would have no trouble sliding the joints together.
With a 2mm gap and a tad of prep this type of joint could be welded with complete confidence, even with a low powered welder.


Just my 2p
Cheers
Paul G Rescued attachment backing strip.jpg
Rescued attachment backing strip.jpg

View User's Profile View All Posts By User U2U Member
Agriv8

posted on 23/1/10 at 12:56 PM Reply With Quote
quote:
Originally posted by MK9R
quote:
Originally posted by Daddylonglegs
quote:
Originally posted by Agriv8
Id be tempted to sleve weld an internal tube then drill through and a spot of puddle weld on existing rails.

regards

Agriv8


My thoughts exactly. Would give it much more strength than just joining/bracing the tubes externally.


Can't do that as chassis rails are angle inwards and want to build the new front end up on the bench so i can get it nice and straight and welded all round


Dont see wht the angle has anything to do with it ? you would not be able to weld the iner tubes to your new or the existing but nothing to stop you slidimg the tubes int correct position when lined up

Build as you are planning to do.

cut 4 internal ( you could equally do external but internal would look Pritier ).
put a marker line arround center point of each tube (and note length of tube )

Slide the internal tubes into exisiting chassis leaving a couple of mm exposed position new nose section.

Gently slide the inner tubes foreward into the new ( this should help to hold your new nose square ) keep sliding forwad until your 1/2 wat line is visable between old and new chassis do samw for the other 3

tack weld ( check measurements )

Weld away.

then as you know the lenght of you inner tube drill and puddle weld

regards

Agriv8





Taller than your average Guy !
Management is like a tree of monkeys. - Those at the top look down and see a tree full of smiling faces. BUT Those at the bottom look up and see a tree full of a*seholes .............


View User's Profile View All Posts By User U2U Member
skinned knuckles

posted on 23/1/10 at 04:01 PM Reply With Quote
so long as you are a good welder and get good penetration, not just a surface weld then in theory, the join should be as strong as the metal you are welding, but as a belt and braces approach, i would weld some 2mm angle over the join as well for 50mm either side of the weld. i would use angle so that it acn be welded to the inside and lower surfaces of your box section so as not to effect the panel fit.





A man isn't complete until he's married, then he's finished

View User's Profile View All Posts By User U2U Member
Peteff

posted on 25/1/10 at 07:58 PM Reply With Quote
I'd just cut the old one off and weld the new one on. Weld is all that holds the rest together anyway. Anything else you do to it is just going to look bodgey.





yours, Pete

I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.

View User's Profile View All Posts By User U2U Member

New Topic New Reply


go to top






Website design and SEO by Studio Montage

All content © 2001-16 LocostBuilders. Reproduction prohibited
Opinions expressed in public posts are those of the author and do not necessarily represent
the views of other users or any member of the LocostBuilders team.
Running XMB 1.8 Partagium [© 2002 XMB Group] on Apache under CentOS Linux
Founded, built and operated by ChrisW.