Clay Sculpting for Fibreglass

[irk miller]

No need to reply, but I didn't list the items or amounts to come up with that figure, so how do you know my math was wrong. I used the amounts needed in your list, sure you can make it cheaper per pound if you make 100lbs. My numbers were for making one batch of your ingredients and amounts.
Whatever

Here's the breakdown of that recipe:

2.5lb Bees wax ($9.45/lb): $23.63
1lb Microcrystalline wax (6.39/lb) : $8
1pt Mineral oil (21.99/gal): $2.75
1lb petroleum jelly ($.32/oz): $5.12
6.25lbs talc ($.50/lb): $3.13
--------------------------------------------
11.5lbs plastalina = $42.63 vs $42.44 for the Hobby Lobby plastalina

After checking your ingredients I came to a total of around $103 for would looks like it would make 10-12lbs of clay.

$42.63 is not $103

 

[o1marc]

$42.63 is not $103

Look, I didn't come in here to stir up shit or troll. You posted a list of ingredients to make a batch that would yield about 12lbs of plastalina with no pricing. I checked pricing for those small amounts and came up with the $103 price. You came back and posted pricing of 100's of pounds of product to make a large batch and then gave a price per lb. Most of us would never need to make that much clay and agree the Corvette guy used way too much when another product could have been used for the back fill. The clay is just used to form a temporary shape and then removed after the glass work is done. How is modeling clay not the right product for this purpose? Isn't plastalina just another form of modeling clay, Micheals calls it Plastalina Modeling Clay.
You list the cost for the ingredients on a subsequent post coming up with $42.63/11.5lbs versus just buying the clay ready to use for $.19 more. Why on earth would anyone needing 10lbs of clay go through the hassle of buying all the ingredients and mixing their own when it's just cheaper to buy that product ready made for less than a quarter more. Some of your price per pound pricing was based on buying large quantities of up to 100lbs making your buy-in investment much more than the $42 price. I'm sorry you didn't like the way I posted "that we all have those products laying around" and felt you needed to personally attack me.

 

[Hurco550]

You guys are both way off.

I just use playdough.

Here you can buy 3 lbs. 4 oz. used for $8.00

https://www.swap.com/item/gdf/8329511530/?a=1&gclid=Cj0KCQiAlpDQBRDmARIsAAW6-DMLDtS8qW4Ssuz4dtiSL0MAgp8MQ8afNF1a4mjTxe0XRRbul1Xm7aMaAljvEALw_wcB

I think we need to look at the real issue here.....

WHO THE HECK BUYS USED PLAYDOUGH????

 

[irk miller]

Look, I didn't come in here to stir up shit or troll. You posted a list of ingredients to make a batch that would yield about 12lbs of plastalina with no pricing. I checked pricing for those small amounts and came up with the $103 price. You came back and posted pricing of 100's of pounds of product to make a large batch and then gave a price per lb. Most of us would never need to make that much clay and agree the Corvette guy used way too much when another product could have been used for the back fill. The clay is just used to form a temporary shape and then removed after the glass work is done. How is modeling clay not the right product for this purpose? Isn't plastalina just another form of modeling clay, Micheals calls it Plastalina Modeling Clay.
You list the cost for the ingredients on a subsequent post coming up with $42.63/11.5lbs versus just buying the clay ready to use for $.19 more. Why on earth would anyone needing 10lbs of clay go through the hassle of buying all the ingredients and mixing their own when it's just cheaper to buy that product ready made for less than a quarter more. Some of your price per pound pricing was based on buying large quantities of up to 100lbs making your buy-in investment much more than the $42 price. I'm sorry you didn't like the way I posted "that we all have those products laying around" and felt you needed to personally attack me.

Dude, the price per pound in my first response is not quantity discount pricing. It's all from Amazon in the quantities needed for the recipe, except for the talc which is from a ceramic supply company. I followed up to say you could make it for half the price with bulk pricing, ie $20 per 12lbs. To do large scale work like a body panel you'll need much more than 12lbs of clay, so bulk pricing actually does apply to this process. Also, like I said before (you clearly don't read through all the comments and pick and choose what you want to respond to) all clays are not the same. Different clays have different working properties. As Doc Rot pointed out in an earlier comment (for which my first recipe comment was a response to), you can't use clays with sulphur as they effect the curing of certain resins, latexes and epoxies. I provided two sulphur-free recipes. I think it's ironic that you, a powder-coater, is making the price of a material the justification for not using it. The best material for the job is the best material and sometimes you have to bite the bullet on price. Like I have previously stated, I do this for a living. I've been doing it for over 20 years. The plastalina type modeling clay is an industry standard material for most casting applications. As pointed out, micro-crystalline wax is used in foundry processes too, so practice and familiarity can be a good segue for those wanting to learn and expand their skills. Yes, you can use other clays. I often use regular old pottery type clays to do casting, prototyping and moldmaking work. Here is an example:

But, the material has deficient working abilities and is significantly limited on work time. Plus it shrinks up to 12% as it dries which makes it's application to the subject of this thread and mold making inferior.

You walked into this thread critical of the process and you try really hard to maintain that stance despite inaccurate evidence, bad math, and a suddenly sensitive attitude.