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modifiying searra uprights
andy9391 - 23/12/04 at 02:38 PM

just a quick note im building a locost based on the collins chassis,using searra uprights and maxi lower ball joints to make the ball joints fit ive bought some tapperd reamers from Axminster tool@s,www.axminster.co.uk part number RDO13066 cost £4.14 took me 30 mins to ream out both lower holes and the ball joints fit spot on.i have also made my front bracket tube in line and then modifide my wishbones to suit,any comments would be greatly recieved

RPS - 23/12/04 at 05:49 PM

I will be interested to hear what others think, but don't these tapers need to be machined accurately to be durable and safe? Can you get them accurate enough with a hand held tool?

If you can, well done to you. It will save a lot of hassle and expense.

The website link looks useful.

Cheers,

RPS

andy9391 - 23/12/04 at 07:57 PM

as long as you keep a uniform pressure on the reamer and check the fit with engineers blue to find any high spots you can get a good fit,also if you rig the upright in a drill press you can get even pressure,you just need to mesure how much thread you have sticking out to get them equal

NS Dev - 23/12/04 at 10:47 PM

It'll be fine!! That sounds fine to me. There is no black magic to reaming a couple of tapers out slightly, they will fit a treat, and the steel forging of the upright is ductile enough that any high spots will be pushed away as the tapers are torqued up anyway.

Don't worry!!!!

NS Dev - 23/12/04 at 10:49 PM

Just to upset a few folk as I have had a beer or two now..................I would'nt worry at all about the reaming, but I would worry about using Sierra uprights!!!! They give sh1t geometry for the front suspension!!!

DEAN C. - 26/12/04 at 06:52 PM

I thought the geometry would be more affected by the positioning of the wishbone balljoints,have another beer you'll see straighter

wilkingj - 26/12/04 at 10:28 PM

I just had a look at those reamers... How do you know they are the correct taper gradient for the tpaer on the ball joint?

There is no data on the website to how many degress it is set at.

MikeRJ - 27/12/04 at 07:03 PM

quote:
Originally posted by wilkingj
I just had a look at those reamers... How do you know they are the correct taper gradient for the tpaer on the ball joint?

There is no data on the website to how many degress it is set at.



Was going to ask the same question. Those reamers were not designed for making accurate tapers, but are made for enlarging holes in thin sheet metal. If they just happen to have exactly the right taper for the maxi balljoints then they are a very inexpensive solution (proper taper reamers are v. expensive). However, it would be a big coincidence if they are.

keith2lp - 27/12/04 at 09:00 PM

Hi

I searched for a tapered reamer to do my sierra uprights but I was unable to find one at the correct angle of the shelf but I could of had one ground (expensive).

As I have access to a machine shop I made a cutter from tool steel and then set them up in a pillar drill. This worked fine and I have since done some by hand that Luego had not cut deep enough.

If any one lives near southampton and needs them cutting I may be able to do them for you.

Keith

[Edited on 27/12/04 by keith2lp] Rescued attachment car 007.jpg
Rescued attachment car 007.jpg

Rorty - 28/12/04 at 03:20 AM

keith2lp, nice Locost work, well done.
UK supplier of taper reamers (they can supply just about any reamer).
Some interesting reamer information here and here.
American site, but correct automotive taper reamers for Ford and GM (Vauxhall and Opel).
You want more reamers?

NS Dev - 29/12/04 at 12:33 AM

quote:
Originally posted by DEAN C.
I thought the geometry would be more affected by the positioning of the wishbone balljoints,have another beer you'll see straighter


Exactly my point!!

Look where the top balljoint is in relation to the bottom one, the Sierra upright was designed for the macpherson strut, a system which effectively has a top wishbone of infinite length. The Average locost wishbone could NOT be accused of having infinite length!!!!!!!!

I know every man and his dog are building cars around these uprights but the geometry with the cortina upright is much better (still not ideal I will concede).

The sierra ones are used cos they are cheaper and more readily available. If I had not used Cortina uprights, I would have used manta/chevette/viva etc etc ones, i.e. ones from a car with double wishbones like the Cortina, or fabricated some using Viva pattern stub axles, available from trailer manufacturers very cheaply. The tapers on these fit those of Sherpa van tie-rods, instead of the transit tie-rod ends used with Cortina uprights.

Anyhoo................. I can whittle on all I like on here but that doesn't get my car built and I have a "dry/not dry sump" conundrum to whittle about in my garage!!!

DEAN C. - 29/12/04 at 05:28 PM

I know what you mean,I had a dry ,not dry sump system ,both within the space of a couple of seconds on the hairpin at Elvington!
Just fitted my mark 2 shortened sump,if that doesn't work it will then get a proper dry sump set up,just hoping I dont have to go to that expense though.
A slight pause in oil supply has cost me about £200 in bits

andybod - 14/1/05 at 09:29 AM

did this reamer from axminster tool,s work o.k trying to help tks in spain with some info on getting his hub,s reamed out does anyone have any further info on ball joint taper required thank,s

tks - 17/1/05 at 09:32 PM

could some help me a bit?

i have really now idea wich reamer to buy,

and by Axminster i can't find the tool mentioned above

RDO 13066

some one could help me a bit pleaze?

Tks

tks - 17/1/05 at 09:38 PM

i'm gonna buy the reamer

and this is what i'm going to do to make him ready for my drilling machine

i will buy a bolt M8 x 65 Any grade.. (non full threaded)

will drill a vertical hole in the reamer, tap it to M8,

cut the head of the bolt

turn in it in..while reaming it will only go further down soow thats not a problem....

finished maked a reamer..

many thanxs for the locost guy..

TKS

Rorty - 17/1/05 at 10:20 PM

quote:
Originally posted by tks
i'm gonna buy the reamer

and this is what i'm going to do to make him ready for my drilling machine

i will buy a bolt M8 x 65 Any grade.. (non full threaded)

will drill a vertical hole in the reamer, tap it to M8,

cut the head of the bolt

turn in it in..while reaming it will only go further down soow thats not a problem....

finished maked a reamer..

many thanxs for the locost guy..

TKS

If I understand you correctly, you only want to insert the M8 bolt into the reamer so you have a hex head with which to turn it.
If that's the case, well, for a start, the shank of the reamer will be hardened, maybe not as much as the cutting edges, but still bloody hard. Too hard to drill.
Anyway, it would be much easier to use a T-handle tap wrench (see below) or a T-handle Jacobs chuck. You'd have more control with a T-grip than with a spanner or ratchet.

SilverFox - 20/12/05 at 12:39 AM

Have I measured right, i.e. measured the maxi b/joint as best I could and got Large dia = 17.3 mm (.681", small = 15.5 (.612" over length of approx 14.8 (.582".
My simple math suggests this a taper of 3/4" per foot. e.g. 17.3-15.5= 1.8 mm Divide by /2 = 0.9 mm to get change on one side and then length of 14.8/0.9 equals about 1:16 which equates to 3/4" per foot.

Rorty provided a measure once of 17.3 mm for the large end with 7.15 deg. I can only replicate Rorty's 17.3. Given that I always trust Roty's data I must determine where I am wrong

This thread has some good stuff, but I can't reconcile the various numbers to terminolgy on both sides of the pond.
The Chadwick & Trefethen site noted by Rorty has a size 2, #85020 with 1 1/2" per foot and an angle that agrees with Rorty at 7.15.

So from all accounts it should be 1 1/2" taper - so where am I out to lunch grrrrrhh
Andy9391 references a number RDO13066 but I would need some other info inorder to cross reference,
I still need the reamer.
Cheers for any input.

MikeRJ - 20/12/05 at 02:41 AM

I may be wrong but I think that when the angle of a taper is specified, it is the total angle formed by the taper, i.e. double what you have calculated.

SilverFox - 21/12/05 at 01:10 AM

Good point. So if I use the total, it would be say 15.5 divided by 1.8 = approx 8. This gives 1:8 or 1 1/2" per foot.
Will visit the tool store ans see what they have.
Thx

scotmac - 27/12/05 at 08:48 AM

Rather than the sierra or the cortina uprights, wouldn't it be better to use a pinto/mustang-II uprights? Racers/rodders have used them for years, and they have good geometry: 7% KPI. and w/ their good offset, i believe we can a pretty good scrub axis. They are also readily available for CHEAP, since soo many people have used them for soo long.

[Edited on 27/12/05 by scotmac]

locoboy - 27/12/05 at 06:24 PM

what do MK and the likes use to modify them on an exchange basis?

locoboy - 9/1/06 at 12:12 PM

Any one got any clues?

Im also after a definative answer on the taper size for a maxi ball joint so i can go to my local machine shop and het them to ream the upright out for me.

Ta.

Gav - 9/1/06 at 01:22 PM

Why not visit you local machine shop with the maxi balljoint in hand so they can look at it?

scotmac - 10/1/06 at 03:07 AM

No comment on the pinto/mustang-II stuff??? Is it not very prevalent in the UK??? Sure is in the US.

Also, is it possible to use racing based wide-5 stuff...ie, like the Wilwood starlite 55 hubs? What uprights would u use w/ those hubs on a locost???

[Edited on 10/1/06 by scotmac]

seventhheaven - 4/2/13 at 10:34 AM

I've done the sums too. Rorty and the guys above are right (7.15). I've bought a stack of recommended hand reamers and measured them (some were over a degree out!). Every one was wrong and only one fitted a drill chuck. Hand Reaming? Come on guys.... You're only kidding yourselves.

Even when mounted in a good quality pillar drill, I still had to 'true' it with a Dial Test Indicator. That took 30 minutes as it's not that easy doing it on flutes and I'm out of practice.

The correct angle is indeed 7.15 (1.5 inches per foot). I'm afraid you'll probably have to import your reamer, it's the cheapest way (£60). Then you'll need a large drill press or mill to perform the reaming itself. There are no half measures here, IT'S A BALL JOINT!

Also double check your top hat / mushroom adaptors. The pair I bought were 0.15 out. He's since stopped selling them.

For more info, see my reply on this thread 'Taper Angle'.

'Chadwick Reamers'. If you speak to them, they are available in several qualities and I can definately say they performed perfectly for me. Unlike others they also fit large drill presses although if you speak to them nicely, they might make one with a threaded end for a milling machine collet/chuck.

adithorp - 4/2/13 at 12:05 PM

Nice info but... Holy thread resurection!