I just collected my RHS tubing and was about to start cutting the parts out using the excellent McSorley book chassis PDF plan dimensions
(http://mcsorley.net/locost/drawings.htm) but have noticed several differences between the book (2nd edition) and the McSorley plans. To make matters
worse I was also using a cutting guide spreadsheet that differs slightly from the book as well.
(http://www.esbconsult.com.au/ogden/locost/mirror/fstdcutlist.htm According to the file properties was written by someone called Rory Perrett)
Below is a summary of the main differences. Some are just a few millimetres so I’m guessing that what Ron meant by “leaving just minimal filling for
truing up”, but some of the difference are a bit larger.
G1 & G2. Book & Cutting Guide = 688mm. McSorley 686mm
J1 & J2, Book & Cutting Guide = 1476mm. McSorley 1472mm
K3 & K4, Book & Cutting Guide = 508mm. McSorley 512mm
LA & LB, Book & Cutting Guide = 330mm. McSorley 341mm (Looking at page 49 in the book I think the book is wrong)
N1 & N2, Book & Cutting Guide = 688mm. McSorley 691mm
O1 & O2, Book & Cutting Guide = 406mm. McSorley 478mm
O3, Book & McSorley = 965mm. Cutting Guide 1016mm
V, Book & McSorley = 965mm. Cutting Guide 1067mm
W1 & W2, Book & Cutting Guide = 635mm. McSorley 638mm
Y, Book = 813mm. Cutting Guide = 1067mm. McSorley 914mm (Looking at page 51 McSorley & Cutting Guide look incorrect.)
As anyone actually made a chassis using the McSorley pdf plans and did they have any problems following the dimensions? (I notice that Jim McSorley
is a locostbuiders member as well, but is building a non-book chassis. Thanks for making the plans available Jim – I don’t mean to be too
critical!)
Mark
No help from me I'm afraid 
Just posting to say Rory Perret is the secretary of the locost car club, cracking chap, bought a 4-2-1 crossflow manifold and a set of motorcraft rear
shoes for £14 from him a couple of weeks ago...
Sorry I couldn't be of more help ;(
Tony Bond (Unc)
I got the metal supplied cut according to the book, however the book has inaccuracies in it.
For example, lenght C (which is not on your list) is about 10mm too short. Also, G1 and G2 vary along C depending on engine so their lengths will
change. What was annoying is the book text explicitly states the lengths for the Ford 1300 engine, but the diagram shows the positioning for
non-Ford.
I guess that the list you have may be based on his experience, but as you say, a few mil is not a problem.
quote:
For example, lenght C (which is not on your list) is about 10mm too short.
JohnFol
According to the book, McSorley plans and the cutting guide, C is the same length as Q.... so if C is too short does this mean Q is as well?
I suppose the best method is to cut the parts as I need them rather than in advance? It's a shame because my garage is full up with the Escort shell
and I thought pre-cutting the chassis parts would keep me occupied until I manage to get it shifted.
Mark
quote:
I suppose the best method is to cut the parts as I need them rather than in advance?
Get the exact measurements and angles for all tubes, cut all the tubes in one go, and assembly is a doddle. Just watch where you tack though, ie so
that you don't have to grind so you can fit H and FU1 & 2. Don't leave a mm or 2 to grind off, this is a nightmare, you think it's not much but it is
very difficult to keep the cut square.
Dunc.
quote:
Don't leave a mm or 2 to grind off, this is a nightmare, you think it's not much but it is very difficult to keep the cut square.
quote:quote:
I suppose the best method is to cut the parts as I need them rather than in advance?
I would always recommend fitting pieces as and when you need them, just to be sure.
I've certainly wasted money having paid someone to make the cuts as per the book.
N1 and N2 need a 40 degree cut, but it's not shown.
The uprights of La Lb Lc Ld (can't remember which) are about 8 mil too short, but you can use C to make 2 new ones, as C is about 10 mil too short.
Perhaps the £250 is a challenge, rather than an estimate 
I'm not sure about the book corrections you're asking about, but check out an Australian site by Greg Rowell, for other apparent corrections...
http://members.ozemail.com.au/~rowellg/Pages/correct.htm
... also check out his main page (http://members.ozemail.com.au/~rowellg) for some photos of a true blue ozzie locost!!!
I only cut when i need it. The book has a lot of errors. 1" is 25.4 mm, we only get 25 mm rhs here so almost every tube length is wrong.
I made a triangular jig (2 * rhs 75mm sections of 3 meters each) so i never get a 'twisted' frame. I made it rotateble so i can weld and twist and
shuffle all night long 
McSorley info is good, as you can print off info on each piece with angles for each given accurately. As others have said it does pay to cut and align
(without welding) to make sure that everything fits
I'd like to see the biceps on the man with the file !!
Cheers all...
I appreciate the feedback on my CAD drawings... constructive critisism is always encouraged.
Just so you know how those drawings were derived... I did everything in standard inches and then asked the computer to apply metric measures as a
secondary dimension in the drawings.
I chose this approach for two reasons: 1) I plan to build with inches since all my tooling is standard measure, and 2) I had to decide early on which
unit of measure appeared to be more accurate from the book. Since the book design had so many exact inch figures (25" here, 42" there, etc.) I
assumed that the original design was done in inches. It only made sense to try and keep the units of measure the same as the original design so my
model would line up with the book as much as possible.
The internal rounding of inches to metric is precise since it was done by the computer... but any marksman will tell you that precision and accuracy
aren't the same thing.
I do hope the drawings don't cause anyone too much grief... but I've not heard of any errors so far. Then again, I've also not had anyone tell me
that they actually built from the drawings yet.... and yes... I'm planning a custom build where only few book dimensions apply (latest work in
progress 3D model was posted over the weekend BTW).
Again, thanks for the input.
-Jim M.
quote:
Since the book design had so many exact inch figures (25" here, 42" there, etc.) I assumed that the original design was done in inches
I remember being in the 1st year that my school taught in metric. My brother was the year above and had to convert.
I'm 34, so if the book is in the 60's then it will be imperial
Ron's version isn't that old - don't forget, he built it for his son within the last 10 years.
(Now the original design - that's another matter.)
David
I hadn't considered the impact of the school system on Ron's book... that would definetly explain why the metric measures in the book are more
accurate; While the initial measures may have been standard (off of the Westfield), most of the builds used as examples for the book would have been
done in metric and the numbers would have been validated time and time again.
One other factor is based on knowing what Westfield used for their original design to sufficiently satisfy the court's mandate of being different
from a true Seven. In otherwords, what unit of measure did Westfield choose when designing this chassis?
Seeing as how so many of the "critical" tubes are measured in exact inches (A1, B1 for instance), I think it would be too much of a coincidence to
have designed the Westfield in metric. And I don't know my UK history as I should, but at the time the Westfield was designed (and by whom we can
only guess)... would they have defaulted to standard or metric?
Anyway... regardless of the Westfield design... what I realized last night having given it more thought is that most of the angles and final lengths
in my CAD model are the derivative of laying out the "critical" tubes and then using an CAD approach known as "extrude to surface". This is, in
effect, the opposite of "grind to fit"... it is more like a "grow to fit" that can only be accomplished in a CAD environment.
The reason I mention this is because the angles and lengths derived in CAD are the result of asking the computer to determine the final length on most
of the tubes given certain contraints (usually outer edge alignment or meeting at a vertex, etc). While it might be precise, the accuracy of such a
method is based on the accuracy of the initial or most critical tubes used in the layout. I would consider A,B,C,E & K to be the most critical tubes
in the whole layout (geometrically, not structurally). Everything else in in one way or another driven by the length and/or angle of those tubes.
While the computer may be precise, the accuracy of the model is still driven by human input; the length of the critical tubes. Again, seeing as how
most of the critical tube lengths are exact standard measures (whole inches), I could only assume that standard measure would be the most accurate way
to start.
Ah yes... but then the real gotcha; working with 25mm tube instead of 25.4 mm tube can have a big impact over all and I think this is where a metric
builder will detect errors in my drawings. All of the tubes in my CAD drawings are a full 1"... or 25.4 even though the metric measures are rounded
to exactly 25 in the drawing dimensions. So you can see that anywhere that the thickness of the tubing effects the overall length, the metric
measures will be off by .4 and sometimes .8 of a millimeter. This is definetly compounded even more over the entire chassis.
Perhaps I should rework my CAD drawings in pure metric with exactly 25mm tube? 
Sorry mates... unless someone is wanting to finance that
endeavor, I'm afraid the idea is going to have to wait.
Sorry for the long, theory filled post... as you can see, I greatly enjoy the subject.
Cheers,
-Jim M.
Jim,
I know what you're talking about, I encountered the same problems doing my cad models. You have to define what you are going to use as your main unit,
decide what the main driving dimensions are for the tubes then take a leap of faith. Then there's the rounding problem. But I doubt any of us are able
to cut all the tubes to exactly the exact dimensions and ±1mm on all dimensions is more believeable and attainable.
Can't remember what your using to create the model but it seems you create the datums then the tubes from those. I used Proe and modelled each tube,
to the book initially, then assembled them into an assembly as you would do in real life. This can also be another source of errors. Can you export
your model in step or iges for a comparison to my model, I would be happy to do the same.
PS. I felt it better to move E and FU forward by a few mm so that the nuts for the suspension brackets would fit better. I felt that they would hang
too much of the LA and FU too much and didn't look quite right. Did you pay much attention to this?
Dunc.
Hi Dunc,
I'm also using a parametric, feature based modeling package (of questionable origin so I shouldn't name it directly ).
I used the same approach as you, but I was careful to crate each piece as cross-section that is blind extruded to both sides leaving the origin of the
part in the middle with an over all length similiar to the book. At this point however I didn't introduce any cut angles or additional features on
the ends of the tube unless the angle was critical to the defining the layout (like K1/2 must have 40 degrees on one end and 50 on the other).
I then created mating contraints in the assembly like you would in the real world (same as you). I used edges and vertices quite often which makes
compound angles rather easy. The last step however is unique... As each part was fully constrained, I switched the definition of the extrusion from
blind to 'up to surface'. This allows for very dynamic revision of the model without worring about loosing the face or edge used in the contraint
definition. It also 'cuts' the part with compound angles an to exactly the needed length automatically.
The great thing about this approach is that I can change a few critical parts and the whole model is revised automatically. It plays off the
parametric nature of a feature based model... but I didn't have to key in the parameters (I didn't use equations for instance)... it only relies on
the dependencies & contraints.
I haven't considered moving E or FU1/2 laterally... only transversly. And I haven't given much thought the the bolt clearance issue either. It seems
that the issue only exists on the rear lower wishbone mount... all others have plenty of clearance. As for how much the brackets overhang LA and
FU... I haven't focused on that part yet... thanks for the heads up.
I think I can send you IGES files... but I'm not sure if I have to export each individual part with the assembly, or if exporting just the assembly
will take care of business. There are nearly 50 part files and it might be a bugger.
I'll try to email you directly and we'll see how it goes. I can import Pro/E seamlessly... that would be cool.
Cheers,
jim m.
With ProE you can create relations, layouts and skeleton models. Thinking back this was the way to. I did use the skeleton models for the suspension
geometry though, very useful feature.
You say you can read ProE models ok, would you prefer I just sent the ProE models, 2001 version, in a zip file or would you prefer a shrinkwrap in
Iges format, 1 part as opposed to many that the iges recognises.
Dunc.
Hi Dunc,
Would it be possible for you to send me the CAD models in ProE format for the chassis and pinto engine.
Many Thanks
Mark S
dexteria@clara.co.uk
Well I intend to build the McSorley 7+4 chassis. I'm sure somebody has done it allready, but if not I guess I will be the first??? Hehe, I keep
wanting to call my project the McSorley 7 now 
. Dont want to get anybody in trouble though. I will still get the book of course, but when that
brass plate gets made for my dash, you can be sure the McSorley name will be there. No, I'm not related nor do I work for this fellow, but after what
I have retrieved from his website I think the credit is well justified! Mr. Champion certainly deserves just as much credit as im sure most of you
master builders see him as "The Man".
The point of my message, be it in the wrong place perhaps, is its nice to see that there are still lots of people out there that share knowledge for
the love of the hobby above the all mighty buck hehehe.
I can finally make my childhood dream come true
Mike Larsen
Ontario, Canada
I'm building a McSorley 442, that's the one that's 4 inches longer(2"in the engine compartment 2" in the tapered part of the cockpit) 4 inches wider
and 2 inches higher. I've added another 2 inches in the streaight part of the cockpit because I am 6'4". I am using Jim's previous design before he
modified it to suit a standard nosecone because I am fitting a Rover V8 and need the extra little bit of width. Lolocost do nosecones up to 3inches
wider than standard so I should be OK.
Previously I was building my own design for Jaguar components but decided to abandon it as the Jaguar bits are just so heavy.
I am hoping to try an RV8 engine and gearbox in the chassis this week. Looks OK apart from the alternator. I see the Dax demonstrator uses a small
aftermarket unit mounted higher and closer to the engine centreline
Thanks, Jim, great work!, and I love that animated chassis on your web site. I might paint mine those colours
John
I'm already planning a mk2 locost with a V8. i'll be interested to hear how the engine fits when you've tried it.
John
Dunc came around to visit a few weeks ago and completed a design for a standard book chassis using Pro E. I'm currently cutting and welding to this
design. If all the parts fit I'll publish Dunc's plans.
However, I'm very slow at cutting and welding, so most of you guys will probably be past this stage by then. At least it may be of use in the
future.... (assuming people can still find an Escort donor).
Many thanks to those who are building with the drawings I've provided. Seeing a finished build from my drawings will be very rewarding (hopefully
I'll have one of my own soon enough!) Hearing of how and what others are able to accomplish with my plans makes it all worth while. I'd be truly
honored to see a locost registered as a "McSorley 7" and I fully support the idea.
Thanks again for the kind words and inspiring feedback.
-Jim M.
Jim
Been using your standard book drawings - I'm 3/4's thro the chassis and your plans have been spot on so far.
Thanks m8
Jasper
YAY!! Chassis building starts next week!! I finnally freed up my garage, painted the floor, and found all my tools hehe. A friend at work has a side
business building trailers and has told me he can get me the metal stock I need for from 75- 95 cents a foot Canadian funds!
I think I will get a website started to document the build.
I am just in the planning stages at present. In the light of the above discussion, could somebody please confirm for me that the tubing we get in the
UK is now all metric. ie. I need to be working to 25mm not 25.4mm etc.
Thanks in advance,
Mart.
I may be wrong, but i'm pretty sure the steel i bought was 1" and not 25mm. If I remember, I'll check when i get in the garage.
John.
I was told by my stockholder that all rhs erw in this country is imperial, i.e 1" not 25mm, and 1.5" (38mm) not 40mm
John
Thanks Guys. At least I'm getting off on the right foot!
Mart
The supplier I phoned said I could have either size.
James
As for the trailing arms, it doesn't matter which use use as long as they are the same..
Jim Mcsorley
I havent had chance to look at your web site yet but will shortly but have you modeled an IRS version if not do you have plans?
Regards
I have looked at your site and praise where praise is due. Fine work! The drawings are so much easier to work from and as long as they are accurate
measurements which I think everyone is finding they are I may be building another Sorley7.
Nice One!
Cheers Gremlin...
I know of at least 5 people (probably more) building directly from the current drawings on my site and I haven't received 1 critique so far.
There were some early ideas that I incorporated a long while back... thanks to Kevin Muir who is the first 442 builder I learned of, and whomever
suggested I provide metric dimensions as well... ta.
I don't have any plans for an IRS chassis... mostly because the Sierra doesn't exist over here (and I can't find the US version Merkur to save my
life).
I recently received a copy of the "build you're own Tiger Avon" which uses the Sierra. I have to be honest... I was a little disappointed by the lack
of detail. The Tiger book is definetly not for the beginner.
Send me a Sierra and I'll gladly produce drawings for it!
ciao,
-Jim M.
I'm building a mcsorley 442 ,Superb plans btw. It will be badged as a McSorley 442-7 and pics of build pogress will be on the site soon.
I'm also building a McSorley 442-7, and again, will be badged as such. Thanks Jim!!
So far all measurements and angles have been bang on.
At this stage, to try to keep things relatively straight forward, I intend to use the rear sub frame from the Sierra (although this could change!?)
Therefore I shall be making some modifications at the rear. As I know nothing about designing chassis I shall be using the plans/measurements at:
http://web.ukonline.co.uk/acwsj/help/help_pix/seirrarear(a).jpg
I have set up a simple web site with photo's of the build at http://mysite.freeserve.com/cheffy
As I know even less about html than I do about locost building it is a very simple site made with templates, so no taking the p**s!! If I ever get
round to learning html I'll improve the site then!!
Cheers, Mart.
I've finally got around to up loading the CAD files for a standard book built chassis that Dunc produced for me.
He went to a lot of trouble to reduce the amount of compound angles in the design.
I cut all my tubes to these measurements and they fitted together fine.
The files were created using a package called Pro E. If you would like to download the drawings click here:
Locost Zip Files
The file is just over 2.5Mb in size. I'm not sure if these can be read by any other CAD package.
Mark