Has anyone ever painted the black on rally caps?

[Lyle24961]

A different way to do the sides

The top method described by others is the best for the top and I use a different way on the sides.

To paint the sides I disassemble and put one piece of tape around the outside to stop the paint. With a small round brush full of paint start at the inside corner and flow the paint to the tape in one stroke. The ridges help guide the paint and with a little pratice the results are good enough for me.
Lyle

[george culolias]

Thanks for all the answers *NM*

[Joe Lucia (12484)]

Re: What's wrong with Jack's idea about wiping

Terry------

There is such a thing as a "stronger but lighter pushrod" but the that term only has meaning when it's in the context of "as compared to what".

Generally, pushrods get stronger in several ways:

1) by getting shorter

2) by increasing tube section diameter

3) by increasing wall thickness

4) by increasing material strength

Theoretically, if one had an engine which used 3/8" OD pushrods of .060" wall thickness and made of 1010 steel, one could go to 5/16" OD pushrods of .060" wall thickness and made of 4130 steel and have a pushrod which was lighter but of approximately equal strength.

To take another example at the other end of the scale, L-88's were originally supplied with 7/16" OD pushrods with .080" wall thickness and manufactured of 1010 steel. If one were to convert to 3/8" OD pushrods with .080" wall thickness and manufactured of 4130 steel, then one would have pushrods of approximately equal strength, but considerably lighter. In an L-88 used in a racing application, the reduced pushrod weight of such a conversion might be beneficial. If the pushrods were adequately strong, the 3/8" would be a "no brainer".

For a 5,000 RPM engine, I don't think that pushrod weight is going to make a whole lot of difference. For an L-36, a 5/16" stock-type pushrod is going to provide adequate strength and it's going to be just about as light of a pushrod as one is going to be able to obtain without going to some exotic material.

"One piece" pushrods are fine but, while they have certain theoretical advantages over "welded ball" or "pressed-in" tips, they also have certain disadvantages. The "one piece" and most "pressed-in" tips are "180 degree" pushrods. This means that the pushrod tip can only rotate 180 degrees in the rocker arm socket. "Welded ball" tips are 270 degree tips. This means that they can rotate up to 270 degrees in the rocker arm socket. For most applications, this is capability is "moot". For higher lift applications, it can be quite important.

Most GM factory pushrods of 3/8" OD used for big blocks were/are of welded ball design. While many folks tend to "shy away from" welded ball pushrods since they fear that the ball might seperate from the tube, the welded ball design is a PRODUCTION-VALIDATED design. In my consideration, this gives it HUGE credibility.

[Terry Fiala (21624)]

Re: What's wrong with Jack's idea about wiping

I have never seen a welded ball design fail but I did take apart an engine with them in there and they were having problems. I remember playing with them to figure out how they were made. In the process I found some of the balls were sort of loose or could be wiggled. That was on a 396 I took apart once. Many of the push rods were bent which probably contributed to the condition. The tips of the push rods were flacking away The lower end of the engine had several destroyed bearings (did not knock though). The rocker assemblies looked as though they starved for oil I figured someone ran it dry or something or the lower end was so bad that he rockers just were not getting enough oil. Rockers were badly gaulded, push rods bent. The rocker balls had the groves in them for oil and you could see part of the grove worn into the rocker. Thanks for the comments and information. Nice to learn something new! Thanks, Terry

[Harold# 43147]

Re: Has anyone ever painted the black on rally cap

There is a masking product called Liquid Mask (Bob Dively Model Air Craft) you can buy it on line from hobbie suppliers. it is a liquid Latex you brush on (put two coats on) after it dries cut out with a rasor blade or exacto knife and peel away the part you want to paint.This is compatable with all paints.I use this also for plating when I want to plate different materals Copper Brass Nickel ect on different areas of the same part. Hope this helps.