Wednesday, February 1, 2012

New Toy.

Well, my trip to Macon went well. A friend accompanied me along the way, and we made it from Dallas to Macon and back in right around 32 hours, including loading the lathe in the back of the truck. So, now I'm back in business with a real lathe, which will help a LOT with some of the upcoming projects.

Here is the new-to-me Enco 13x40 lathe




How else could I build a SBR'd SKS, or a suppressor or five?

I've got some new tooling coming in soon that should help with building the Hi Point drum mags. It doesn't seem to matter what I do, every time I build a mag out of thicker material, I wind up goofing up the design or it winds up not having enough internal room to allow the rounds to feed right.
I plan to build the mags out of .04" thick 4130 sheet this time. This is only slightly thicker than the factory .03" mag material, but it is 4130 so it can be oil quenched and hardened.
Barring that working, I also have some .035" 4130 sheet on order. If it comes down to using that, I can make a mag to factory specs but weld on an extra set of plates in the feed lip area to keep the drum spring pressure from bending the lips outward. The more room I have inside the magazine, the easier the rounds will feed upwards, and the less amount of friction I can get away with, the better.
The problem is not width so much as it is depth. The rounds have to travel up the magazine at a slight upward angle, and in the last few mags I pressed and welded they would bind up and keep the top round from pointing upwards enough to load properly. This has been my biggest hindrance in building a functional magazine.
I am also considering building a radius brake that would allow me to press these out quicker. The press brake die I built prior to my move does work, but it takes a while to align the sheet metal correctly and then use the hydraulic press, all the while keeping the sheetmetal exactly in place. This is time consuming and makes bending a mag tougher than it should be.

I used to have a simple brake like Harbor Fright and others sell like this one.
but it is only good for simple bends and is not good for building boxes or pans.
However, the design would be easily replicated such that instead of bending on a sharp edge, a radius could be used as an upper forming edge and the mag metal wrapped around that radius using the lower brake finger. Prior to that, I could bend the rear edges of the mag inward, so that after forming the radius on the front, I would simply insert an aluminum welding form inside the completed mag, squeeze the mag together the rest of the way, clamp it tightly, then weld the seam on the rear of the mag. The aluminum form on the inside would prevent warping and ensure perfect repetition of a completed part.
I'm having to MIG weld the mag assemblies together at the moment until I can acquire another TIG. Anyone familiar with welding knows that the MIG process puts a lot more heat in the weld area than does TIG. There is also a lot more grinding to be done to the finished product when MIG welded as compared to a TIG weld. Once I get the money together to purchase a new TIG, those mags will benefit from thence on.

Prior to making a brake, I have to get a new milling machine so I can machine the parts necessary to build it. Thankfully, I have a new mill picked out and hope to acquire it later this month as funds allow.

That's it for now, more as I get to it.

2 comments:

  1. That's Macon, GA, I take it, based on the times. Quite a trip, but glad you scored on the lathe. I'm enjoying your updates, and eagerly awaiting progress on the HP drums.

    I'd also eagerly await progress on the SKS, except that SBRs are illegal in WA state, so I can't commission one. :(

    Well, I still want progress reports, as something that neat is salivatingly delicious, even if I can't have one.

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  2. Yessir, you guessed correctly! Macon, Georgia. A far piece for me to drive but not too far for a good deal on a great lathe.

    I'm on hold with the hippoint drums at the moment while I wait on the metal brake. I got in some .04" thick 4130 strips the other day and I'm just waiting on the bending machine to get here so I can form some mags. I'm pretty hopeful for what's coming this way.

    To the right of your screen on my blog is a photoshopped image of an sks in a tapco intrafuse stock that has been SBRd. I'm curious as to the finished product's functionality, but I think it will look cool and be fun to take to the range.

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