[yosuthnmasa]

I'm making progress..just real slow. Don't want to FUBAR anything. Here's a pic of my trunnion and rails. Wanted to get some opinions on whether it looks like it fits well at the length I have the rails right now. Or, should I remove some more? I think the sides will draw closer in to the sides of the trunnion better when I get the center support installed.

This leads me to my next question. What do you guys do for the center support. On ACE's website, Max mentions how he uses a bolt that is tapped on both ends. I'm not really sure how to do this, so I went ahead and bought the "bushing" from TAPCO. What do you use through the "bushing" to secure it tightly on both sides of the receiver? A rivet? I tried to fit the ones I have through the bushing and it is just a little big. The smaller rivets for the trunnion would fit, but of course are too short to go all the way through.

A picture of the top of the receiver with trunnion.

edit for pictures:

 

[Winn R]

I sharpen the edges, it brings the sidewalls in tight to the trunnion and prevents oil canning of the sidewall when the rivets are installed.

My center supports are made in the shop out of quarter inch rod. The total length is equal to the total width of the receiver. The ends are turned down to equal the combined thickness of the lower rails and sidewalls.

As soon as the lower rails are in place, snap in the center support and weld.

It looks good!!

 

[yosuthnmasa]

Winn,

Do you know how the ACE center support is installed? Or, before I actually install the center support, what can I use in place of the center support while I drill all of my holes (to bring in the bulging of the sides)? What's the easiest temporary fix until I get the real center support in?

 

[Winn R]

Sometimes I'm not sure if I'm addressing the right issue--

However: center support for the Ace blank is installed like any other one -- if you are asking how to support the inside of the receiver while you drill your holes: use a 1.25 in. thick piece of wood (or metal key stock if you really clamp it down).

My method, which is always improved by somebody else's suggestion, is to stuff a 1.25 in. key stock into the center, clamp it in the mill, cut the front long, cut the upper rails, cut the bottom, install the trigger guard, stuff in a magazine, jam the front trunnion into the magazine, install the front trunnion, install lower rails, install the center support and then cut off the back and install the rear trunnion. The front trunnion placement is determined by the magazine; the rear trunnion placement is determined by the cover.

An advantage is that riveting the trigger guard can be done before the center support is installed.

Max does it more logically starting at the front but I can't seem to get my magazine well cut in the right place.

 

[yosuthnmasa]

Sometimes I'm not sure if I'm addressing the right issue--

However: center support for the Ace blank is installed like any other one -- if you are asking how to support the inside of the receiver while you drill your holes: use a 1.25 in. thick piece of wood (or metal key stock if you really clamp it down).

It may be the fact that I'm not sure I know what I'm talking about. Below is a picture of what I have that I think I'm suppose to use as my "center support". My question is, how do you install it?

What is 1.25 key stock and where could I get one?

 

[Winn R]

One of the problems of doing yourself is a lack of knowledge of the purchased.

I've not done any of those.

A machine shop can order the key stock but you may be better ripping wood to 1.25".

 

[hcpookie]

Below is a picture of what I have that I think I'm suppose to use as my "center support". My question is, how do you install it?

That center support bushing is inserted into position inside the receiver. A full-length rivet is inserted through the hole and into the bushing, then out the other side. Then a head is formed on the rivet. It it usually flat, and can be formed rather easily with plates and a hammer, or via your press.

 

[sniper69]

also you could use a 8-32 or 10-32 screw to fasten your center support, but it might not look as nice as a rivet.

 

[Co7t]

also you could use a 8-32 or 10-32 screw to fasten your center support, but it might not look as nice as a rivet.

Could one use a full length rivet, cut the head off, peen the ends and then flush it with the receiver?

 

[sniper69]

Could one use a full length rivet, cut the head off, peen the ends and then flush it with the receiver?

the hungarian center supports tha global sells (part number H-522) comes with a rivet. I haven't seen one of the center supports from tapco up close so don't know if there is a difference in size. I would assume there is a rivet that could be used in the tapco center support (much like the hungarian center support).

 

[hcpookie]

The rivets are normally flat heads IIRC so you could dremel a normal-head full-length rivet to a flat head, then peen the other end. I received a flat-head rivet with my AK-100 folding stock kit.

Checked Tantal's site... yeah, from Tantal's site, the rivets are flat-headed on the ends. You can rivet into place, then dremel down flat. Some good close-up pics here:

http://www.avtomats-in-action.com/pro18.html



End result, the installation process is the same as with the rear trunion rivets.

 

[yosuthnmasa]

I tried to fit one of the long rivets from 1-pat. through the bushing and it won't fit through. I think the diameter is too wide. If I were to find the correct size rivet for the bushing, how would I "peen" the end that doesn't have a head?

That leads me to my next question. Is it easier to make something like Winn R uses? Does this require special machinery to make the ends look the way he has his? Maybe someone could explain to me how its done.

edit: After thinking about this more, which ever was is the easiest I'm sure will be the way I take. Just have to figure that out first...given with what I have.

 

[yosuthnmasa]

the hungarian center supports tha global sells (part number H-522) comes with a rivet. I haven't seen one of the center supports from tapco up close so don't know if there is a difference in size. I would assume there is a rivet that could be used in the tapco center support (much like the hungarian center support).

I will try to measure the dimensions of it tonight and let you know what they are.

 

[Winn R]

My special machinery consists of a hacksaw and a drill press.

A piece of quarter-inch bar stock, two dollars at Home Depot will make 20 or 30 of these, is put in the drill press and I hold a hacksaw up to it and cut it down. When the thickness looks about right I stop.

Since there will be welds all along the sides for the lower rails, it's no more work to weld these in at the same time.

And if I have some understanding of what you've got, it sounds like a common ferrule.

Should be able to get those at the hardware store with an inside diameter sufficient to pass through a long rivet.

 

[yosuthnmasa]

Could you explain the dismensions of the center support bar that you make?

 

[Winn R]

The dimensions vary widely--

For instance the RPK is about a 20th of an inch narrower in width on the inside dimension than the standard AK.

I use different rails scrounged up from different sources and they have different thicknesses. I measure an individual receiver and cut the center support to fit.

If you're not going to weld the rails then it doesn't make any sense to weld the center support. I will go to a hardware store this afternoon, pick up some ferules with an ID equal to the long rivet OD, and see how they work.

And going back to the topic with which the thread was started, I put a trunnion into a welded laser cut this afternoon and I just about reached the conclusion that I was better to cut all of the upper rail off in the trunnion area because the weld bled through to the inside.

 

[Winn R]

Got some 5/16 split pins, 1.25" long.

Squeeze in the press and they fit the long rivet well.

They'll have to be cut down to about 1.1". I'll try 'em on the next batch.

 

[Winn R]

support the inside of the receiver while you drill your holes: use a 1.25 in. thick piece of wood (or metal key stock if you really clamp it down).

Center support while cutting.

And I put in a 5/16 split pin and long rivet. Ground the tube to 1.25"-.060-.040=1.15".

The rivet was too long so some was ground from it. Worked good.