Need advice on fabricating a speedster hood

[RansomEli]

Sorry for the double post. The AACA website gave an error message on my first post, so I re-sent the posting. First time this has happened to me.  

 

I'm building a brass-era speedster from miscellaneous spare parts. Basically, I'm replicating something along the lines of a circa 1913 Mercer Raceabout or Stutz Bearcat.  

 

Since I don't have a hood I've got to make one. The two side panels will be straight without any louvers (I'll be using a Franklin air-cooled engine). The top panels will have a slight curve to match the 'radiator' shell.

 

I'm assuming it will cost me too much money to have someone fabricate the hood for me. So I'm going to do it myself. Any advice from someone who has done this and what tools I'll need? 

 

Would working with aluminum be better than steel? What gauge do I need?

 

Thanks in advance.  

Edited February 15, 2017 by RansomEli (see edit history)

[jan arnett (2)]

I would go with steel in case you want to weld.  Is the top going to be flat or curved.  Do you have the cowl yet.  I would look at model T panels for the side and roll the top panel over a welding cyc. if you want a curve.  You can buy a piano hinge and rivet it to the panels.    Make up a buck that goes between the cowl and shell and run lines down the cornor from shell to cowl over the buck.  Use string or tape to visulize what it will look like.  Get some roofing paper and lay it out like you are doing steel and make a pattern, see how it fits and what you have to cut.

[whtbaron]

Aluminum is much easier to work with, but like Jan I would go with steel myself for a couple reasons. 1) I've never welded aluminum and don't have the equipment for it. 2) Not all paints adhere well to aluminum (although it isn't hard to find good primers that do). Since it isn't a load bearing part, you could probably go a little thinner... I might get in trouble with some of the more experienced members here, but it seems to me that most of the vintage sheet metal would be typically in the 18 to 19 gauge range for body parts. With the hood you should be able to get away with 20 to 22 gauge ( that's my best guess anyway). With that air cooled engine, you may want to seriously think about finding someone to punch some louvers in the sides for air flow. If you are uneasy about the task, there is a company (Rootlieb Hoods) that fabricate both 3 and 4 piece hoods for the hot rod industry. Yours would be a custom one off and would probably be a little more costly, but it might be worth a quote to see what they would charge.

[RansomEli]

Thanks for the advice. I don't need louvers because the original hood had none. 

 

This looks like a do-able project, one that I will enjoy. 

 

Quote

 

 

[jan arnett (2)]

Here is a group you want to join on face book.

 

https://www.facebook.com/groups/496619540483459/

[Spinneyhill]

Aluminium also work hardens, so you can't work it too much before you have to anneal it. I watched a bloke making a motorcycle fuel tank: beat, anneal, beat, anneal...

[whtbaron]

The motorcycle tank has a lot of complex curves in it. An early car hood is generally "fairly" straight due to the piano hinges in most of them. That being said, you could venture into curves with a 3 piece hood or the need to match curves on a cowl or more ambitiously shaped rad cover. If you are having to anneal a flat hood, I'd say you are probably doing something wrong. That being said, I think aluminum might be more prone to cracking if it were subject to a lot of vibration. As you will see in some of the other posts here, many hoods have been fabricated with aluminum so it can be done successfully, it just wouldn't be my personal choice to select for a first timer.

Edited March 14, 2017 by whtbaron (see edit history)

[jan arnett (2)]

Did you get your hood fabricated?

pictures please.