Hy Mr. Riley,

I'd like to know what's the difference between 'tapping holes' and 'threading'.

Tks,

Fabiola.

Hi All. I am from a rookie team. Kindly take time to answer my queries regarding the cost report.

1) There are some components which are not listed in tables and we have to cost them as if we have made them. Can we cost them as if we have bought them ? If yes, how do we change the currency from Indian National Rupee to US Dollar as in the cost report.


2) In case of some materials, AIR is mentioned in column of cost. What is AIR?


3) In the FCA input sheet, there is one sheet for assembly where we need to fill in all the parts, materials, processes and fasteners. Then there is another sheet corresponding to Part (named part_1). what exactly is this sheet for? Then there is another sheet of Cross sections with item order before every row. What is the significance of this sheet?


4) During costing materials which we have bought as made, if we are not able to deduce the processes involved, can we simply cost them as bought? What is the penalty in this case?

Hi all,

Does anyone know how to cost long and short drive shafts? I was thinking on sending an AIR for each as we bought them but it is strange to me that not a single drive shaft appears in materials table. Any guess?

Thanks a lot.

AIR is an add-in request.

I believe drive shafts must be cost as made, but I'm not 100% sure on that.

Thanks Essayee. I'll wait for if anyone else answers. I thought in that option as well but I was looking at the parts they say that have to be cost as made and these shafts didn't appear.

Well, thanks for your answer

Fabiola
I take "tapping holes" as using a hand tap to create the thread while "threading" is done using a machine.

Ani_V
1) All costs need to come from the standard cost tables, pretty sure if you bought the part and it isn't listed on the cost tables you need to cost it as if you made it.

2) AIR = Add Item Request...each competition has a different deadline for when the cut off is

3) An assembly is made up of parts some of which you will have you make yourself. The part sheet is for the parts you cost as made for the assembly. The cross sections sheet is for the cross sectional areas of tubes and other stocks, it converts from english to metric.

4) I have run into similar problems with trying to figure out what processes were used, I used the processes that I thought were logical. What the penalty for costing something as bought when it shouldn't be I cannot answer, that is probably something Mr. Riley should answer.

Alex_sevdub
I agree with Essayee, cost the drive shafts as made...at least that's what we have done.

Thank you George. If you both agree I'll do that unless Bill in his coming back says the contrary.

Good weekend!

Hello all,

I see that several other teams here are using Taylor Racing components for their Drivetrain system. I was just looking for clairification regarding the costing of the components used to spring load the axles in this type of system. I see that the plug and snubber is listed in the materials table. Are we able to assume the same unit price for the plunger (used on the inboard side) as the plug (outboard side)? If so, are we able to include the spring cost on the inboard side with the unit cost of the spring plunger? I was originally planning on just using the rapid prototype process for both the plug and plunger (I didn't see the plug in the materials table the first time I went through it)... but I found it a little strange the plug was listed and not the plunger, so I figured maybe we could use the same unit price for both? If anyone else using the Taylor Racing components could clear this up for me (or Bill when you get back), it would be greatly appreciated. Thanks in advance!

Michael Kelly
Drivetrain Team
Lakehead University ThunderWolf Racing
www.LUFSAE.com
mkelly3@lakeheadu.ca

Hey again guys. A guy on my team just asked a pretty good question in respect to something I apparently completely overlooked in the rules. The rules say all weights must be computed using official density tables. I've been using google for my numbers (although for example for composites I've been finding the density of our specific layups & volume fractions). Is there indeed an official density table, and if so, does anyone have a link to it? I thought I had just about every document on www.fsaeonline.com, but I guess not...

Hi Essayee,

I have a density table from the organisation but I don't know if it is still on the web as I was given it by a teammate.

In case you don't find it I don't mind sending it to you. Let me know.

I'm back and thank everyone for answering in my absence. All the responses look correct, but here is a quick summary for copmleteness:

Threading: correct, 'tapping hole' is just that, using a hand tap on a pre-drilled hole. 'Threading' is a lathe operation.

You can't cost anything as 'bought' unless it is listed in the materials or fasteners tables. So there are no conversions needed because the tables are all in dollars. If you cost it as you made it everything still comes from the materials table but you add processes to get to the finished item.

The required spreadsheet is called '2010_FSAE_eBOM.xls'. This spreadsheet is required to be submitted, but does not contain enough information to comply with the judge requirements, which means you have to submit additional information. There is no required format, but the 'fca_inputs.xls' gives you the minimum fields required to show the costs of parts and assemblies. This sheet essentially duplicates the software inputs/outputs. My recommendation, however, is if you use it format it so it is legible and in a good sized font so the judges can read it.

Drive shafts, axles, half shafts, whatever the term you use are all cost as made.

On the Taylor Race snubbers, the cost include the spring. I have never actually seen these, only read the website so someone tell me if we're missing something from the tables. My intention was to use the same cost for both sides of the half-shaft.

The question on official densities is a good one. That was the plan for 2009 but we dropped it as too cumbersome. You should use the actual density for your material. The important thing to remember is the cost is on a mass basis so as long as the volume and density give you the right mass then the cost will be correct. We check mass at the event generally, so make sure that is correct for your parts and adjust density to match. We'll update the rules to clarify this aspect for next year.

Thank you for the answers Mr. Riley. I guess that means I won't be needing that table Alex, but thanks anyway for offering.

Working with the plumbing sections of the car right now...does anyone know what process to use for attaching fittings to hoses? Can I assume that hey magically get connected since no one in their right mind would make their own hoses for this? Or should I be using, say, Crimp Wire and just be prepared to explain to the judges that the tables don't consider crimping fittings? Thanks.

Hi

There is right now one Appendix C3, http://www.fsaeonline.com/Downloads/Appendix_C3.pdf

and one eBOM
http://www.fsaeonline.com/Down...s/2010_FSAE_eBOM.xls

Is it the latter that is the one we should use?

Regards
Maria

Hi

Can I do one assembly with both front and rear upright instead of separating them?

As far as I understand, the important thing is that the parts and assemblies listed in the appendix is in the right system and not how I make up my assemblies and the containing parts. Is this correct?

Thanks.

CFS_Maria,

That is the exact explanation I got last year, so I'd assume it's still true.

I'm trying something different (at least from how we did it last year) and not making individual part files for components that are listed in the Materials Table (ie, Fuel Injectors, Dampers, etc.). Is anyone else doing this? I remember that there were problems last year at VIR when an "expected" part didn't show up on the full BoM, and if it's not a separate part, but rather a material line item within the assembly, this could happen. Any advice Bill?

Does anyone know if we can cost a part as cast even if we actually machined it. If you were to have a 3000 car production line you would obviously cast it instead so I figured this would be acceptable, can anyone confirm this?

Thanks!

You can only cast parts as cast if they were actually cast. The manufacturing process used has to match the one that you cost it as. Even if you'd do it differently with a full production run, you have to cost it as machined if it was machined.

Thanks D Collins Jr. but I was also hoping Bill you could confirm this to me. If we could cast our differential assembly it would literally cut our cost in half, so it just doesn't make sense to me that schools that are able to afford to actually cast it would get that advantage as oppose to the ones who can't.

D Collins Jr: Fittings to hoses get assembled the same way as most everything else, using assembly labor. Most will be 'Assemble, 1 kg, interference'.

CFS_Maria: The Appendix C3 and eBOM posted that you reference are the latest and greatest and what you should use. You can organize the assemblies/parts anyway you want but keep in mind the judges are reading 140 reports and having a seperate line item for front and rear uprights may be more clear, less confusing and help you to avoid discussing it with the judges. But you're right, the Systems are very important as different judges review each system so if you put engine parts in body the engine judge may not see them.

D Collins Jr: I don't see a problem with having injectors for example as not a separate part but make sure it goes somewhere logical like fuel rail assembly. Remember I work on the rules and tables and the judges have their own preferences but the safest thing to do is have an injector part in a fuel rail assembly. That way it will be most obvious, especially when they are looking at your eBOM.

LU Drivetrain: David is correct. You can't cost a part as cast if you don't cast it. If you buy a part and required to cost it as made you can cost it as cast. See rule C3.6.1. The reason we do this is because we don't want to have the judges and students debating whether a billet part could be cast at the competition. The billet parts wouldn't have draft and could have undercuts, thin-thick wall sections, etc that would be impossible to replicate. This was a hotly debated topic two years ago when we wrote these rules and in the end we decided this was the best. If you have ideas or comments feel free to email them to me at katklauz@aol.com for discussion for the 2011 rules, but it would have to be something that is a go/no go assessment. We are trying to get away from all subjective assessments. That is why we have one price for all aluminum alloys. Because we couldn't tell what you have anyway so why incentivize 'creative costing'.