STI Aluminum frame to slide fitting question

[tk2]

I picked up a STI 2011 aluminum frame to build a carry gun with. My question is, can I fit the slide to frame by milling both the slide and frame, or do I need to cut on the slide only to fit it?

I've read a little about aluminum being surfaced hardened only, and am a little hesitant to mill on the frame.

[ExtremeShot]

Tim,

You have to measure the height of the rails on the slide and compare that dimention with the height of the groove on the frame. Then you have to measure the width across the rails on the frame, and compare that measurement with the width between the grooves on the slide. Normally you have to take off material on the bottom of the slide and off the sides of the frame rails.

D

[edit for correct name..sorry Tim]

Edited December 3, 2009 by ExtremeShot

[tk2]

Tim,

You have to measure the height of the rails on the slide and compare that dimention with the height of the groove on the frame. Then you have to measure the width across the rails on the frame, and compare that measurement with the width between the grooves on the slide. Normally you have to take off material on the bottom of the slide and off the sides of the frame rails.

D

[edit for correct name..sorry Tim]

Darren, I was worried about cutting through the surface hardening of the aluminum frame. Do you think I should just go ahead and cut the frame the same as I would on steel frame?

Tim

[sperman]

Tim,

You have to measure the height of the rails on the slide and compare that dimention with the height of the groove on the frame. Then you have to measure the width across the rails on the frame, and compare that measurement with the width between the grooves on the slide. Normally you have to take off material on the bottom of the slide and off the sides of the frame rails.

D

[edit for correct name..sorry Tim]

Darren, I was worried about cutting through the surface hardening of the aluminum frame. Do you think I should just go ahead and cut the frame the same as I would on steel frame?

Tim

I don't know anything about the frame in question, but you can't surface harden aluminum.  You can, however, anodize aluminum, which would help with wear.  A clear hardcoat would leave the aluminum a matt grey color.

[tk2]

I called STI and talked with them and they said there frames are not anodized. He did recommend I have it anodized after the gun is built.

Thanks,

Tim

[John Nguyen]

I called STI and talked with them and they said there frames are not anodized. He did recommend I have it anodized after the gun is built.

Thanks,

Tim

Do you happen to know what type of aluminum they use for their alloy stuff? 6061 or 7075? I'm in the process of hard anodizing also, but the place that does anodizing needs to know what type of aluminum it is before they work on it. And where are you sending it to get it hard anodized?

[Toolguy]

It's very important to know the right alloy. Different alloys are processed differently. For example, if you tell them 6061 and it's really

7075, the frame will be eaten away and destroyed when they run it through the 6061 process. It's probably 7075, but you need to know

for sure ahead of time.

[tk2]

Toolguy, thanks for the heads up.

John, I do not know the type of aluminum they used, I'll call STI and post back when I find out. I don't have any place in mind to do the anodizing. Who is doing yours? If you don't mind, how much does it cost to get it done?

Thanks,

Tim

[John Nguyen]

Toolguy, thanks for the heads up.

John, I do not know the type of aluminum they used, I'll call STI and post back when I find out. I don't have any place in mind to do the anodizing. Who is doing yours? If you don't mind, how much does it cost to get it done?

Thanks,

Tim

Tim,

I'm having Scott (owner) of Springer Precision take care of everything for me.

Quoted from his email:

"We process it here and have a local company that does the anodizing for a large AR15 manufacturer. "

"1-2 weeks, cost depends on the size of the part, frames generally run around $90. "

Scott is on here also but you can email him directly: scott@springerprecision.com

I've heard nothing but great stuff about Springer and I'm so glad they do hard anodizing also.

A few posts down: http://www.brianenos.com/forums/index.php?showtopic=94667

-John

Edited December 4, 2009 by John Nguyen

[ExtremeShot]

Darren, I was worried about cutting through the surface hardening of the aluminum frame. Do you think I should just go ahead and cut the frame the same as I would on steel frame?

Tim

I understand. Sounds like you got some answers. Milling the frame rails then anodizing would be a lot easier than cutting the slide grooves wider. Listen to Warren (Toolguy). Warren and i have been good friends for years and there's not many people out there with his knowledge and experience.

D