Help Request -- One or two piece bolt carrier??

Well our group hopes to hit the machines running in Jan, 2014.

First we need your help in to decide which way to go on the bolt carrier.

1st. Is the tradition one piece bolt carrier as shown in the RG-G drawings.
       Good points
               1st. One strong piece.
               2nd. It has been done before for many a Gatling build.

2nd. The two piece bolt carrier that has shown up in several builds.
       Good points
               1st. Don\'t have to cut blind holes
               2nd. Material savings, don\'t have to cut off a lot off of the \"front\" area.
               3rd. Good for a group build. On the front half put it in the vice and make the flats in several passes and then using a ball end cutter make the groves in a couple of passes. Then cut apart of course. On the rear drill holes they are drilled through then reduce the size of the back area and then cut apart then reduce and cut again till they are all cut apart.
        Bad points
               1st Two pieces that will have to be pinned or screwed together.      

At this time I (one member of the group) am leaning towards a two piece bolt carrier.  

WHAT DO YOU THINK??

Of course will be asking about bolts and barrel contours in later threads.

Please need the advice of those that have done this before us.

Later 42rocker

There are no strength issues with the carrier, it only carries the bolts.
Concentricity and alignment with the barrel plate are critical.
The two piece only needs alignment pins, the assembly holds it together.
Your tool & die guys will know the best method for machining,
based on the equipment used.

I used the two piece approach and connected the two with a rabbet and dowel pin. This allows easily boring the holes using a small carbide boring bar, mine came from Mcmaster-Carr, and keeping the holes straight and true. After the two halves were completed, I broached the Hex hole through the center with the parts assembled.

The two halves were machined using a 3/8\" shoulder bolt through the center hole and a 3/16\" dowel pin to maintain concentricity and timing. Using this approach the features may be machined on a fixture plate mounted to the  machine table. The attached photo shows this appraoch being used on the Front Frame Bow.

nitewatchman

Thank you both for your input. Any other thoughts?? Please?

Later 42rocker

[quote name=\"42rocker\"]Well our group hopes to hit the machines running in Jan, 2014.

First we need your help in to decide which way to go on the bolt carrier.

1st. Is the tradition one piece bolt carrier as shown in the RG-G drawings.
       Good points
               1st. One strong piece.
               2nd. It has been done before for many a Gatling build.

2nd. The two piece bolt carrier that has shown up in several builds.
       Good points
               1st. Don\'t have to cut blind holes
               2nd. Material savings, don\'t have to cut off a lot off of the \"front\" area.
               3rd. Good for a group build. On the front half put it in the vice and make the flats in several passes and then using a ball end cutter make the groves in a couple of passes. Then cut apart of course. On the rear drill holes they are drilled through then reduce the size of the back area and then cut apart then reduce and cut again till they are all cut apart.
        Bad points
               1st Two pieces that will have to be pinned or screwed together.      

At this time I (one member of the group) am leaning towards a two piece bolt carrier.  

WHAT DO YOU THINK??

Of course will be asking about bolts and barrel contours in later threads.

Please need the advice of those that have done this before us.

Later 42rocker[/quote]


I made the carrier in 2 pieces. I pressed the hex bushings in first and I machined a hex plug in my rotary table then located the holes in each half on the rotary table . That way the holes in each half were \"timed\" to the hex.
Ron

[Dreeves]

I would love to see some pictures of the 2 piece carrier if anyone has them to post


Dave

[42rocker]

Dave is still working on photo restore. I\'ll see what I have on file later tonight.


Later  42rocker

[Dave]

Rocker, I do not have pics for this thread... Post them at the bottom and I will put them where they belong.

[42rocker]

Dave and everyone

Just reviewed a lot of the material that I have download from this site and found I don\'t have anything on it.

So picked up the phone and called one of the other builders in our group and found that all of our bolt carriers are together, but we might be able to take one apart and take a few pics of it and write up something for this thread. I\'ll see him after Church on Sunday and take pics at that time and go from there.

 

Later 42rocker

[42rocker]

Well went to canemakers (member here) on Sunday night and took a few pics and asked him to write up what we did. So finally getting a chance to post it.

 

From canemaker

\"\"\"Here is the way I made them.

 

   Turn the OD of both parts on the Lathe, leave enough on the smaller one to mill the flats, and drill a 3/8 hole thru on both. Set up the parts on the rotary table. Drill and ream the 10 holes for the bolts, and one hole for the dowel pin. Drill c-bore and tap two 10-32 bolt holes, to hold the two halves together. Put the dowel pin hole on a centerline leaving about .025 into the hex tubing.

This will keep the flats oriented at all times. Drill and ream 3/4 inch dp. on the facing halves  slip fit  for the hex tubing. Using a couple of washers between halves, carefully mill the flats.\"\"\"

 

Now lets see if I can get some pics posted.

 

Later 42rocker

[attachment=9895:11.jpg]

[attachment=9896:12.jpg]

[attachment=9897:13.jpg]

canemakers $500 lathe in the background. He did redo a few things.

[attachment=9898:14.jpg]

[attachment=9899:15.jpg]

[attachment=9900:16.jpg]

[Dave]

Nice!

[42rocker]

Dave

One of the interesting things is that the Brass came from two different scrap yards. We have a scrap yard a few miles from us and another about 100 miles away. Happy to say that canemaker drives one of those hybred cars and gets great milage.

 

Later 42rocker

[Dreeves]

Great looking parts. Glad you were able to get them posted. I think that\'s the way I\'m going to go  


Dave

[canemaker]

I finally joined the Gatling Gun Forum, so if you have any questions, I will be glad to answer them.

 

 

Canemaker

[42rocker]

Welcome Canemaker to the site. Canemaker is the lead tool and die man that is leading our group. That is his nice Gatling in our pics that I have posted.

Hope to see you Thursday night if all is good with your wife.

 

Later 42rocker