Another Super 7

These are the seat belt adjuster buckles for the shoulder harnesses. More acid etched brass cut from my artwork. I cut lines into them (about half the thickness of the brass) to aid in the folding and positioning of other parts to be soldered on later.
http://www.scalemotorcars.com/forum/...013/02/124.jpg
These are the seat belt anchor pieces also cut from brass. Still a little clean up needed, but this is close to how they look fresh from the acid etching.
http://www.scalemotorcars.com/forum/...013/02/125.jpg

I gotta learn this trick!

This is the beginning of the tire master. Again I utilized PVC from the hardware store; this time a plumbing fitting that was just about the right size. It was a little thin on material where I wanted to make the sidewall, so I built it up with some CA so I could have more curvature to the sidewall. I cut the sidewall on the lathe freehand but used traditional tools to cut the bead; the tread was cut on the mill. The tread is patterned after an Advan tire.
http://www.scalemotorcars.com/forum/...013/02/126.jpg
http://www.scalemotorcars.com/forum/...013/02/127.jpg

I added the sidewall detail and lettering…
http://www.scalemotorcars.com/forum/...013/02/139.jpg

Looking good man, keep it coming!

Thanks!
I am pretty close to being done with the master for the Weber carbs. There’s about 60 pieces to make this part, maybe a few more… The hardware will machined for each individual carb after I cast copies.
http://www.scalemotorcars.com/forum/...013/02/144.jpg

I use Legos to make my mold frames. (The plug in the center of the tire master is made of Renshape.)
http://www.scalemotorcars.com/forum/...013/02/196.jpg
Not only are the Legos easy to work with and reusable, they also can be stacked to fit more molds in the vacuum/pressure vessel. This is the rim master on top of the tire master to cast the first half of the molds.
http://www.scalemotorcars.com/forum/...013/02/197.jpg

Quote:

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Originally Posted by ScaleMaster

I am using the hydrochloric acid you don't care for. Granted, it has a caustic aroma to say the least. The hydrogen peroxide helps speed up the process as does working with warm chemicals.

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OK...I might have to give this a try. I'm having a lot of issues trying to get some .010" brass etched. I don't know if I have a crappy piece of brass or what, but it is not etching well at all. I've done some .007" just fine. Going to try some .009" this weekend.

What kind of formula are you using in mixing up your hydrochloric acid and the hydrogen peroxide?

Mike

The formula varies since the peroxide acts as an oxidizer and both chemicals seem to change strength during the etching as the brass that is dissolved dilutes the solution. 50/50 is a good start. I have experimented with formulas ranging from 25% peroxide to 25% acid. It does not seem to matter much.

I have had good luck going through 0.030. But even burning all the way through 0.010 can take several hours.

I'm really interested to see the moulding process since that's my biggest problem with my models. Looking forward to the results :)

OK... Here is the mold and a casting from it for the outer rim for the wheels.
http://www.scalemotorcars.com/forum/...013/02/209.jpg

Here is the first cast tire on the first cast rim outer. I cast both parts from molds I made off masters I created. The tire is hollow and easily stretches over the one piece rim. It is so soft and pliable that it should “squat” under the weight of the car.
Front:
http://www.scalemotorcars.com/forum/...2013/03/29.jpg
Back:
http://www.scalemotorcars.com/forum/...2013/03/30.jpg

Outstanding result! I am going to have my first crack at molding and casting later this week. Wish me luck!

OK, good luck! And it often takes a few tries to get what you want. I have found taking notes of what I did each time to be helpful in fine tuning the process.

I’ve been casting centers for the wheels too. Still not sure which design I’ll use, the five spoke or the web, or maybe something different all together…
http://www.scalemotorcars.com/forum/...2013/03/50.jpg

Thanks for the well wish and I vote for the five spoke...just my humble opinion.