Question about mounting gun in a spring compressor

[GrizzlyMan]

Spook, I am trying to make another spring compressor using the pipe clamps 1/2", only thing I noticed is the length of the bolt.

If there could be a way to find a similar thread, but longer size bolt. In some rifles the spring when decompressed extends out the back around 2", then one adds the spring guide making the situation much worst. I compared two different pipe clamps, one from Home Depot and the other from Harbor Freight, and both have similar length in thread for adjustment.

[Kirk B]

Nice compressor Bandit. I was going to build one that style but I thought the pipe clamp thing would be a little easier.

Griz, I used a 3/4" clamp so maybe that has a longer thread? Per Dave the screw might be replaced by one from a c clamp of the proper size but I haven't looked into that yet.

[rogn]

+Just want to addd a bit of food for thought, my first compressor was my better than average drillpress. Lotsa run for precompression, heads turn with the capw/o friction can be readily adapted to almost any design, just make an adapter/plate to fit in chuck. First one was engine valve with leather glued on.

[shooterpr]

It ok an 8" (C clamp or other) of free play on spring compressor for pre-charge spring?

It enough length to work on various types of AG or do I need more or less length?


JC

[daved]

8" is more than enough, 4" is probably adequate, I replaced the screw on my Pony bar clamp with the screw from a 6" c-clamp I had kicking around, it just happened to be the same pitch and diameter.  Later.

Dave

[hogginhank]

This is a great thread. I am in the process of building one so I can learn on my gamos I have. I will take pics and post up the process. I will be welding some and use some wood as well.  As daved said I will "Steal" some ideas from all the compressors I have seen so far..I am a welder so I will use the metal where I can for strength and adjustablilty(not to mention I am not the greatest with wood). I will be using a 12" piece of 5/8" all thread with a 5/8" coupler instead of the cut down C-Clamp..I was going to ask but I think daved answered my question about the amount of travel I will need. I was going to try for at least 7" of travel??? Will this be too much,not enough or just right?? Thanks..I hope to have it built by tonight..This dadgum 20 degree weather for south texas is just not right..I guess I will just have to stay inside and build my compressor  ..Thanks again for the great thread.. This forum is really awesome..Adios' for now..Hank

[JMJ in NC]

I finished my spring compressor this weekend. Based on a Harbor Freight 3/4" pipe clamp and plywood out of the scrap box. I opted to have a "floating" middle support that I can position at will. The receiver is held into the central support via a strong bungee. I've got a 1 1/8" aluminum tube in the compressor in the picture just to see how the bungee would fit.

Bad idea (the bungee) or should be okay? Anybody ever have significant movement during assembly/disassembly?

Thanks all - JMJ

[Kirk B]

Anybody ever have significant movement during assembly/disassembly?

As long as the gun's lined up straight and there is do deflection of the 2 end plates, friction should hold it in place, as evidenced by Dave's experience using no receiver restraint. The biggest benefit I think you'll see from your design is that it'll act like a 3rd hand, making it easier to get the gun in straight and keep it straight while you start cranking.

Since I mentioned deflection, I have to say that was a slight problem for me the first time I used my compressor. The plate at the screw end was angled back enough that it wasn't pushing the internals straight back into the tube. I think the tube was in the compressor a little high (too far from the black pipe) and it had too much leverage for those 2 little screws holding the plate in place.

I'm going to epoxy the end plates to the clamp pieces and do a little cutting to try to the gun down closer to the black pipe to minimize that deflection. If that doesn't work, I'm going to have to come up with some kind of shim to keep that end plate perpendicular to the pipe.

[JMJ in NC]

Thanks Spook.

Since the HF pipe clamp is a bit sloppy, I'll give it a try and if it doesn't work out well, I'll redesign. I bought 2 other long clamps to monkey with just in case, but they have less adjustment range.

JMJ

[danials]

Sorry, if this is a dumb question.  I see how these work for compressing the spring, but in my case with a Diana Model 5, the end of the spring tube is a threaded metal cap.  How do I unscrew this cap with a clap applying force to it? 

[Kirk B]

Is the end cap what's holding the spring in place? Sounds like that could make things more difficult. 

[danials]

Yeah, I have unscrewed the end cap once, and the spring forces it off last couple threads.  It took two people.  The spring pressure wasn't too bad if controlled but I'd rather use a clamp of some sort.  Don't want to risk getting shot in the face with the end cap.

[JMJ in NC]

You could try mounting small lazy-susan or similar with a small section of plywood so you can compress and spin. Some folks use a drillpress as a compressor (or a large lathe if you have it).

JMJ

[JimL911]

Try placing a piece of rubber,leather or cork between the end cap and compressor to protect the end cap. Next place two lubed washers between the compressor and the end cap protector. This should allow you to loosen the compressor while turning the end cap.

[bluzjamer]

Rogn show some pics of the drill press compressor in action. Have a 15 speed floor drill press I was thinking of using.