Object Size

[Jezella New User Find all posts View Profile Close Jezella]

Hi all, this is my first posting where I must say that I am pleased to have come across these products where I have not purchased any yet but do have a number of questions.

Basically, I am interested in the Triple Chrome Plating Kits. From reading about the various products and this forum it would seem the most appropriate of kits.

For the most what I hope to do is refinish vintage vehicle parts both internal and external though the latter being to a much greater degree.

My initial interest is in plating 17" steel hub caps. So this takes me to the first question as I have seen it written that these products are more for smaller parts but, what is considered as small parts.

Considering the 17" hub caps. Would it be practical to triple chrome such parts using either a 6 or 12 volt battery. Considering the size of these hub caps and the fact that they are only about 1.5" in thickness, what would be the most appropriate kit size.

I am also hoping to refinish the vehicle window frames where the size of these items are in the region of 24 x 15 x 1

Perhaps what I ought to ask here is what space is required between objects being plated and the sides of the containers. So in the above window frame example, could I triple plate in a container of say 30 x 20 x 6 inches.

Another question is ampage. How accurate do caculations need to be when with odd shapes this can be very difficult to estimate.

Many thanks for any input

Jezella

[fxstcguy98 Amateur Metal Finisher Find all posts View Profile Close fxstcguy98]

car batteries are limited in their amperage. Chrome takes 1amp/sqin of surface area, 17" dia hub cap will need ruffly 250 to 300 amps to do one side (not counting the sides and back). Anodes need to be 3" to 6" from part and there is 1.5 to 1 anode to part ratio. Also a part needs to be put in the solution so that it doesn't trap hydrogen bubbles and pit the plate. You can't lay the hubcap flat in a thin tank, it's better to put it vert. in a narrow tank. One other thing, you can transfer solutions from one tank to another, but it is dangerous (spillage) and you need seperate tanks for each solution (cross contamination) especially the chrome. If I were you, I would read the caswell manual first, figure out what size of things you are going to plate and consider buying a rectifier if you are going to need over 100amps on a regular basis.
Darrin

[Jezella New User Find all posts View Profile Close Jezella]

Darrin thanks for the input. It is much appreciated and I think that I'll download the manual as this ought to give me a greater understanding here.

Jezella

[mcaswell ******* Inc Founder Find all posts View Profile Close mcaswell]

Don't forget that 2 or 3 12 volt batteries in parallel used in conjunction with nichrome wire strips can effectively control way more than 100 amps if configured properly.

[Jezella New User Find all posts View Profile Close Jezella]

Now this is a thought that I must admit I had not considered.

The following, to do with batteries, I found and think that it may also help the novice, like myself, plater.

Cold Cranking Amps (CCA)

The most important consideration is sizing the battery's CCA rating to meet or exceed, depending on the climate, is the car's OEM cranking requirements. CCA's are defined as the discharge loads measured in amps that a fully charged battery at 0 degrees F (-17.8 degrees C) can deliver for 30 seconds while maintaining the voltage above 7.2 volts.

Batteries are sometimes advertised by their Cranking Performance Amps (CA) or Marine Cranking Amps (MCA), which is measured at 32 degrees F (0 degrees C) or Hot Cranking Amps.

HCA is measured at 80 degrees F (26.7 degrees C), which is not the same as CCA. Do not be misled by CA, MCA or HCA ratings. Multiply the CAs by 8 to convert Cas to CCAs. To convert HCAs to CCAs, multiply HCAs by 0.69.

Buying batteries with double or triple CCA ratings that exceed the OEM requirement are a waste of money for hot climates. However, in colder climates the higher the CCA rating the better, due to increased power required to crank a sluggish engine and the inefficiency of the cold battery. As batteries age, they are less capable of producing CCAs.

One of the major battery manufacturers, Exide, publishes the following table:

Available Power from battery Temperature Degrees F Power Required to crank engine
100% 80 100%
65% 32 155%
40% 0 210%
25% -32 350%
If more CCA capacity is required, two (or more) 12 volt batteries can be connected in parallel. Within a BCI group size, generally the battery with more CCA will have more plates because a larger surface area is required to produce the higher current.

Reserve Capacity (RC)

The Reserve Capacity rating is the second most important consideration while buying a battery. This is because of the effects of an increased parasitic (key off) load and in emergencies. Reserve Capacity is the number of minutes a fully charged battery at 80 degrees F (26.7 degrees C) can be discharged at 25 amps until the voltage falls below 10.5 volts. More RC is better in every case! In a hot climate, for example, if your car has a 360 OEM cranking amp requirement, then a 400 CCA rated battery with 120 minute RC with more electrolyte would be more desirable than one with 1000 CCA with 90 minutes of RC. If more RC is required, two six-volt batteries can be connected in series or two (or more) 12 volt batteries can be connected in parallel. Within a BCI group size, generally the battery with larger RC will weigh more because it contains more lead.


Jezella