In need of small batch cnc work that includes some design

[jxb]

I'm looking for someone that does small batch CNC work that includes some design work, anodizing would be a plus.

If you know of someone or a business I'd appreciate their contact info.

 

[boltfluter]

What do you have in mind? Occasionally I do small runs of various items.
Paul

 

[jxb]

A spacer for a chassis buttstock to increase LOP forward of the cheekrest rather than behind it. The simplest solution is a spacer that inserts at the connection to the action mountpoint.

I'm thinking it should be a fairly simple part to produce. I'll contact you directly this week with details, thanks.

I don't think there will be enough interest/volume for some of the common specialty places like greyopscnc to do a run but I noticed more than a few folks on other sites wishing for the same so instead of getting my local machinist to do a one-off for just me...

I did confirm with the manufacturer they don't produce one, have no plans to, and are not aware of anyone making one. So far they have not pushed back on the idea of a third party doing one.

 

[Fuj]

What chassis are you referring too ?? the AR style butt stocks that
use the buffer tube like the older MDT-HS-3 stocks, you could get
a 1 inch spacer forward of the cheek rest. Years back, I would source
them from "Black Rifle Works". I've seen them at Midway and Brownels,
but normally say out of stock.

So many chassis stock options out there. What is your particular one ??

 

[jxb]

MDT HNT26

 

[jxb]

Turns out: "The XTN interface is now also used in the MDT ACC and HNT26 Chassis Systems."

I think we're on our way with this project. MDT has been very helpful and supportive thus far.

 

[Fuj]

Is your stock the straight unit with solid insert, or is it the
folding version.

 

[jxb]

Folding but MDT confirmed all variants of HNT26 use the XTN interface to mate with the action.

 

[jxb]

I never got enough interest to do CNC run, but here's the initial run of 3D printed in PLA CF for those curious.

 

[tac284]

The prints look good, does PLA CF suit the need or the product would be best out of something like Aluminum/Delrin?

 

[jxb]

The prints look good, does PLA CF suit the need or the product would be best out of something like Aluminum/Delrin?

Certainly metal would be better, I cannot speculate about Delrin. The idea here was to prototype these in 3D printed, but after working with these I think they will likely work fine. The main benefit is after not getting enough interest to do a CNC run even at break-even, this is a cost effective solution as they can be printed to order and in any length the customer wants. I had them printed in 1" and 1.5".

PLA-CF is quite tough, when bolting it in place it comes up solid with no deformation. That said PLA has a lower deformation temp so the concern is when left in direct sunlight it may deform. Only actual testing of that would tell. I generally don't leave my weapons sitting in direct sunlight for long so I'm not sure that's an issue (for me). Still, needs to be tested. It should be noted that PLA begins to deform at 60C so we're talking about leaving it in a closed car, in direct sunlight type temps. Personally I'm not sure this is a concern as who's going to leave their weapon, especially scope in those conditions.

Those that have a stock with XTN interfaces may notice these are flat faces on the exterior whereas the MDT products those radius edges are rounded. This is because they were printed using MDT's XTN specs and files. Totally my fault for not comparing the specs to their actual products in advance. The plan is to print these rounded and not flat going forward. The spacers print to the same fit as the stock to action (my folder). We could likely improve on those tolerances but once it's snugged down there's no movement from twisting or otherwise so...

 

[LVLAaron]

PLA-CF is tough stuff. It softens around 150 freedom units.

I bet if you made them out of this: https://prusament.com/materials/prusament-pc-blend-carbon-fiber/

you'd never have a problem.

 

[jxb]

PLA-CF is tough stuff. It softens around 150 freedom units.

I bet if you made them out of this: https://prusament.com/materials/prusament-pc-blend-carbon-fiber/

you'd never have a problem.

Thanks for that, I passed it on to my 3D guy. He was thinking PETG-CF, but this looks even better.

 

[jxb]

Here's a view of the 1" installed, and the 1.5" spacer beside it with the threaded rod and round coupler. A reminder to those unaware, on the screw in the folder that attaches to the action is a captive bolt, so I chose to use a round coupler with threaded rod to bridge each spacer. This makes changing them out just a few minutes with just a 3/16" ball-hex for the folder bolt. As I had issues with the threaded rod sticking in the action I switched that to a rod with a 3/16" hex on one end. As mentioned above, still a work in progress.


Below is a view that shows the 3D part printed to the XTN specs (flat facets), but stock those are rounded, so that will be changed to match the stock so not only will it look correct, but will fit into the action end as intended.

 

[WhiskeyCharlie]

I’m interested in this, if you’ve got pricing in mind or just want to sell some of the prototypes please let me know. I don’t really plan to use this in the heat so not as concerned about that as long as it can handle a luggage cart in my case at the airport.

 

[jxb]

I’m interested in this, if you’ve got pricing in mind or just want to sell some of the prototypes please let me know. I don’t really plan to use this in the heat so not as concerned about that as long as it can handle a luggage cart in my case at the airport.

I'll have the updated prints here this week and check fit then update pics here. Once good I'll do a post in B&S to keep everything legit with the site rules and you can order from that post.

What length(s) are you thinking about? He can print whatever you like, I have 1" and 1.5" that I'm testing with.

Cost isn't set, but something like $40/ea for one kit plus actual shipping (3D printed LOP spacer, SS coupler, SS set screw). If a person only wants just the 3D LOP spacer a bit less.

I settled on a 1" coupler for >=1" LOP spacer as that's 1/2" each end, more than enough threads, the set screw length matches the spacer and they come in many lengths. I just picked em up from McMaster-Carr as that is an easy button.

Regards,
Jeff

 

[WhiskeyCharlie]

That sounds good, I’m thinking 1” to start. I feel like it’s kind of short for me but don’t want it too long for kids. Savage is sending the 1/4” spacers that should have come with it so I’ll be able to fiddle with that and if I ended up wanting to go to 1.5” can just do that then.

I’m interested in this as much as anything because I read the stock spacers are heavy and you stated some other reasons for inserting here that seemed valid. Thanks for your work on this, let me know when you get it posted.

 

[jxb]

That sounds good, I’m thinking 1” to start. I feel like it’s kind of short for me but don’t want it too long for kids. Savage is sending the 1/4” spacers that should have come with it so I’ll be able to fiddle with that and if I ended up wanting to go to 1.5” can just do that then.

I’m interested in this as much as anything because I read the stock spacers are heavy and you stated some other reasons for inserting here that seemed valid. Thanks for your work on this, let me know when you get it posted.

I believe UPS said they are showing up sometime tomorrow.

Savage eh, yeah I forgot they where doing stuff with MDT. If you haven't already you might want to check that bolt in the folder for which size ball-hex it is, mine is 3/16" (HNT26 manual says one size larger). Also they blue loctite that bolt in the action. Mine wouldn't budge and and I didn't want to apply too much pressure out of fear of breaking something. MDT told me about the loctite and to apply a little heat to the action at that joint with something like a heat gun. I warmed it up just to where it wasn't burning fingers and the bolt came loose easily. I found that joint liked to seize the bolt a bit when I snugged it up. A little anti-seize and no more issues with that.

Adding/removing the LOP spacer takes just a minute or so and the set screws are also 3/16" hex so only that one ball-hex needed in your bag. I wanted the shoulder to cheek piece distance static regardless of LOP, this allows me to not mess with those spacers at the buttpad end.

 

[jxb]

FYI --

SELLING - HNT26 LOP spacers with hardware (3D printed spacer)

Offering HNT26 LOP spacers with hardware for sale. These are printed using PLA CF to order by my 3D guy. I currently have a couple on-hand in 1" and 1.5" lengths. They insert between the stock and the action and include a round coupling nut plus a set screw matching the length of the spacer...

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