I have a cottage business
- posted
15 years ago
I have a cottage business
How about using brass or bronze screws?
In the proper alloy they can be as strong as 18-8 screws.
Wolfgang
Well, I thought I explained that. I can't seem to find a #6x3/4" truss- head in anything but ss. The geometry is critical to function, so I can't deviate far from what I'm using now. Also, bronze I can maybe see (I'm no metallurgist), but is there really any brass alloy that is close to 18-8 SS in strength? That flies in the face of my instincts and experience! Maybe I'm wrong... Robobass
Have you considered plating the parts yourself? Look here-
6-32? or #6 woodscrew? Sheet metal screw?
6-32x1.25 antique bronze finish here:
You could have the Stainless you want gold color - color treated by heat. Standard colors are a bronze color.
Mart> >> On Apr 9, 6:36 pm, " snipped-for-privacy@googlemail.com"
----== Posted via Pronews.Com - Unlimited-Unrestricted-Secure Usenet News==----
---= - Total Privacy via Encryption =---
Caswell's stuff is very good, but I think you could have 500 small parts plated for less than it would cost to set up to do it. Brush plating would be inexpensive, but brush-plating 500 parts would be quite tedious.
The appeal to Caswell's stuff is that once set up, one-off small jobs cost almost nothing while taking anything, even one bolt, to a plating shop costs a job minimum that is never less than $50 and usually more like $100. I'm still using Caswell stuff I bought more than 5 years ago and have used many times. I had two small jobs-in-a-bucket today: one zinc and one tin. The zinc job is a small steel weldment, the tin job is a copper electrical terminal.
News==----
Hadn't thought of that... And the user can try this out himself with a propane or MAPP gas torch. Nice.
Wolfgang
It is around 300 or 350F that bronze occurs IIRC.
Might run small lot test cases. Might be well worth the effort.
Martin
Mart> >> You could have the Stainless you want gold color - color treated by heat.
News==----
----== Posted via Pronews.Com - Unlimited-Unrestricted-Secure Usenet News==----
---= - Total Privacy via Encryption =---
I think the temper colour is more like 480F to 500F for a bronze but that is carbon steel. I have read that the temper colours occur about
100C higher on stainless steel so some trials might be required and an accurate temperature controlled furnace would help.
If you need strength, avoid 6-32 screws. This thread is bad because too much of the diameter of the screw is lost with such a course thread.
On plating, I think zinc chromate gives you a nice brassy color (Think Japanese car parts.).
Zinc chromate typically goes on zinc, not on stainless. If the screws in question are available as bright zinc on steel, it's very easy to chromate them so they look a lot like brass. It's just a dunk in some juice for a few minutes. The juice is available from Caswell.
6-32 x 3/4 zinc-plated truss head screws are available fromSorry I was unclear. The screw is a truss head sheet metal screw #6 x
3/4" 18-8ss. I've been searching a long time, and never found it in gold color. I will try the heat idea. I've got a butane mini torch. But, won't it loose strength if I heat it that much? It really needs to be fairly strong. I did have a plating rig years ago. Maybe I'll get another one. Trouble is, I'm in Germany now. You can't just go out and buy toxic chemicals the way you can in the US. (I bet it's getting harder there too. I've heard of high school science teachers being arrested for trying to order stuff to do classroom experiments that they had been doing for decades!) Robobass
Would TiN coating be a close enough colour match? Think coated carbide inserts...
A better class of cutter regrinding shop would have the facilities to do the work.
Mark Rand RTFM
PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.