Are the the proper screws , there is no listing for strength on the link.https://www.fastenal.com/products/details/24492?r=~%7Ccategoryl1:%22600000%20Fasteners%22%7C~%20~%7Ccategoryl2:%22600039%20Sockets%22%7C~%20~%7Ccategoryl3:%22600041%20Low%20Socket%20Cap%20Screws%22%7C~%20~%7Csattr07:%5EFine$%7C~Want to make sure before I order , I tried McMaster Carr but the shipping would be almost 40.00$.
This thread is of great interest to me as I'm going to be using 10x32 low head socket screws in my QB78 project. My problem is I wanted to use hex nuts in a groove so the fitting assemblies could be positioned (twisted). Without that I would need to have a series of 10x32 holes around the circumference of the holding block. ( this is the block with the "O" ring in it that is under the threaded cap at the end of a QB78).I was planing on using 303 stainless as the body as that is what we use for our products .... i could use 6061T6 but I'm afraid of the 1/8npt failing and sending a fitting flying somewhere un-announced - extremely dangerous. This is one of the reasons I keep my outgoing to -1300 psi in these guns for now. I may be cautious, but I'm fine with that, I don't need to make a gun that is not safe for me or others to handle. I want to die with both eyes and all my fingers still in one piece !wll
Quote from: wll on February 21, 2016, 08:49:25 AMThis thread is of great interest to me as I'm going to be using 10x32 low head socket screws in my QB78 project. My problem is I wanted to use hex nuts in a groove so the fitting assemblies could be positioned (twisted). Without that I would need to have a series of 10x32 holes around the circumference of the holding block. ( this is the block with the "O" ring in it that is under the threaded cap at the end of a QB78).I was planing on using 303 stainless as the body as that is what we use for our products .... i could use 6061T6 but I'm afraid of the 1/8npt failing and sending a fitting flying somewhere un-announced - extremely dangerous. This is one of the reasons I keep my outgoing to -1300 psi in these guns for now. I may be cautious, but I'm fine with that, I don't need to make a gun that is not safe for me or others to handle. I want to die with both eyes and all my fingers still in one piece !wllI am traveling and don't have access to a lot of my info, but 6061T6 is plenty strong for 1/8-27 with proper engagement. Crosman has 1,000s of aluminum P-rod adapters in the field. Use 7075 if want the weight savings and extra strength. Good safety policy BTW.
Wll, i am having a little trouble visualizing exactly what you mean. The sharp threads bearing against the sides of a drilled hole is not good. Concentrated point loading. Look at the "after" pictures in this thread to see how the failure occurs. Tapping the tube abd body as a matched set MIGHT be an option, but i don't have enough info to say.
If you have 8 holes all in one location (radially distributed from each other around the tube) you may be looking at structurally compromising the tube itself.... I hate giving advice without at least a sketch or photo to understand the situation.... Using 8 screws on one fitting would make me wonder why?.... If nothing else, it means you have to ACCURATELY locate 8 holes instead of 3 or 4.... I just don't get it!....Bob
I hate giving advice without at least a sketch or photo to understand the situation....