Wildfowler Posted May 11, 2013 Author Report Share Posted May 11, 2013 He then earned his pocket money by cleaning down the lathe! # I then moved on to the firing pin. My phone had died so i didn't get any picture of it being machined but this it the complete item. Quote Link to comment Share on other sites More sharing options...
TIGHTCHOKE Posted May 11, 2013 Report Share Posted May 11, 2013 Blimey, I thought you were going to tell us he was stuck there! Quote Link to comment Share on other sites More sharing options...
Wildfowler Posted May 11, 2013 Author Report Share Posted May 11, 2013 Quote Link to comment Share on other sites More sharing options...
Wildfowler Posted May 11, 2013 Author Report Share Posted May 11, 2013 Blimey, I thought you were going to tell us he was stuck there! No.. he's a good lad and as obsessive as me so he wanted to get every last bit of swarf off the machine (which if you've ever cleaned down a machine you'll know that you'll be there all week to get it spotless) Quote Link to comment Share on other sites More sharing options...
Chris Bb Posted May 12, 2013 Report Share Posted May 12, 2013 [Rolf Harris] Can you see what it is yet? [/Rolf Harris] Quote Link to comment Share on other sites More sharing options...
Wildfowler Posted May 13, 2013 Author Report Share Posted May 13, 2013 I spent an hour or so tonight roughing out the pocket to take the trigger mechanism. I'll do the last 2 passes tomorrow... Quote Link to comment Share on other sites More sharing options...
harrypen Posted May 14, 2013 Report Share Posted May 14, 2013 (edited) Hi bud , do you not have any concerns about the firing pin shoulder to spring diameter ?? At first glance the spring bearing seat looks less than optimum and looks like the spring may ride over or wear the shoulder in short time my apologise if you've considered this harrypen (fitter/turner , tool room fitter ret.) edited to add (experience suggests a spring bearing shoulder of less than half the diameter of the spring thickness leads to early wear and/or spring expansion over the shoulder ) Edited May 14, 2013 by harrypen Quote Link to comment Share on other sites More sharing options...
harrypen Posted May 14, 2013 Report Share Posted May 14, 2013 you have pm harrypen Quote Link to comment Share on other sites More sharing options...
matt fieldcrafter-uk Posted May 14, 2013 Report Share Posted May 14, 2013 More good work going on ! Il Be interested to watch this process , why don't folks do this more ? Quote Link to comment Share on other sites More sharing options...
Wildfowler Posted May 14, 2013 Author Report Share Posted May 14, 2013 Hi Harrypen, to be honest, i haven't given sourcing the spring a lot of consideration.I calculated the required k factor and therefore the required spring, the one on the picture was one i found in one of my bits and bobs boxes which had the right ID. Its far heavier than i actually need due to the mass of the firing pin but for the time being it will work for the tests... If i cant fins another spring i'll definitely take your point and make a new firing pin with a bigger shoulder. (I've got loads of that material and it only took an hour or so) This is with the pocket roughed out to full depth and the sides cleaned up to the right dimensions Quote Link to comment Share on other sites More sharing options...
Wildfowler Posted May 14, 2013 Author Report Share Posted May 14, 2013 I then turned the vice around 45 degrees and cleaned up the angled sides, debured it and assembled it. The spring i found isn't too far off length wise either ~5mm too long... but the tolerances on it all make for a nice smooth action... Quote Link to comment Share on other sites More sharing options...
matt fieldcrafter-uk Posted May 14, 2013 Report Share Posted May 14, 2013 That is ace !! Will you cock the gun by pulling the firing pin back till the trigger engages ? Your flying through it ! Quote Link to comment Share on other sites More sharing options...
Wildfowler Posted May 14, 2013 Author Report Share Posted May 14, 2013 Will you cock the gun by pulling the firing pin back till the trigger engages ? Yes, thats the plan... Quote Link to comment Share on other sites More sharing options...
harrypen Posted May 15, 2013 Report Share Posted May 15, 2013 the other thing is if you have cut the sear engagement too deep you end up with a shear pin effect,,,,,,,, if that dia is smaller than the striker pin diameter it will / could crack off Hi Harrypen, to be honest, i haven't given sourcing the spring a lot of consideration.I calculated the required k factor and therefore the required spring, the one on the picture was one i found in one of my bits and bobs boxes which had the right ID. Its far heavier than i actually need due to the mass of the firing pin but for the time being it will work for the tests... If i cant fins another spring i'll definitely take your point and make a new firing pin with a bigger shoulder. (I've got loads of that material and it only took an hour or so) This is with the pocket roughed out to full depth and the sides cleaned up to the right dimensions IMG_2049.JPG Quote Link to comment Share on other sites More sharing options...
Catweazle Posted May 15, 2013 Report Share Posted May 15, 2013 the other thing is if you have cut the sear engagement too deep you end up with a shear pin effect,,,,,,,, if that dia is smaller than the striker pin diameter it will / could crack off If the sear engagement was on the back end of the pin, behind the spring, the reduced section of the engagement wouldn't be ( so much ) subject to the forces of the weight of the pin and spring hitting the primer ( and the primer blowing back ). Also, have you thought of having the pin cross-drilled in the portion that protrudes from the back so as to fit an R clip as a safety device ? Or perhaps a reduced section and some kind of retainer ? Quote Link to comment Share on other sites More sharing options...
harrypen Posted May 15, 2013 Report Share Posted May 15, 2013 (edited) page 9,,,,,,,post 172 for gun design/concept refresher,,,,,,assembly 4 Gun assembly1.JPGGun assembly2.JPGGun assembly4.JPGGun assemblysection.JPGGun assembly5.JPG Edited May 15, 2013 by harrypen Quote Link to comment Share on other sites More sharing options...
Wildfowler Posted May 15, 2013 Author Report Share Posted May 15, 2013 (edited) the other thing is if you have cut the sear engagement too deep you end up with a shear pin effect,,,,,,,, if that dia is smaller than the striker pin diameter it will / could crack offThe undercut takes the diameter down to 5.2mm, 30% larger than the striker end which equates to c. Twice the sectional area, so I'm pretty confident that this will not pose an issue. Similarly, as the striker is still 4mm I don't think it will readily fail, especially given the number of times it is likely to actually be fired. If the sear engagement was on the back end of the pin, behind the spring, the reduced section of the engagement wouldn't be ( so much ) subject to the forces of the weight of the pin and spring hitting the primer ( and the primer blowing back ). Also, have you thought of having the pin cross-drilled in the portion that protrudes from the back so as to fit an R clip as a safety device ? Or perhaps a reduced section and some kind of retainer ? The firing pin shown never comes into direct contact with the primer, this is via the secondary pin in the breech plug. The diameter of the rear of the pin is only 6mm so whilst it would experience less stress, if the undercut were located behind the spring the same depth undercut would take it to 2.2mm diameter and in turn be far more likely to fail, and if it were even the same depth, the contact with the sear would still be less due to the radial effect of the different diameters...Not sure if the pics are clear enough of the model but there is a hole in the rear of the firing pin, this was initially going to form a pull back mechanism coupled with a safety, I now plan to thread the backend and put a knob on there to aid pulling it back so will now probably integrate a safety into the main mechanism... Not sure yet! Edited May 15, 2013 by Wildfowler Quote Link to comment Share on other sites More sharing options...
TIGHTCHOKE Posted May 15, 2013 Report Share Posted May 15, 2013 Really looking forward to your next installment W.F. Quote Link to comment Share on other sites More sharing options...
harrypen Posted May 15, 2013 Report Share Posted May 15, 2013 Hi Wildfowler , You will appreciate its difficult to judge these things from an unscaled photograph so I apologise if I seem to be nitpicking however what one man sees another dose not ,,Top marks mate ive followed this from the beginning and would hate for you to "spoil the ship for a happorth of tar" ignore us idiots ,,,,, keep building and posting harrypen Quote Link to comment Share on other sites More sharing options...
harrypen Posted May 15, 2013 Report Share Posted May 15, 2013 I did not understand fully the concept of the shell/breech and trigger mechanism but after looking more thoroughly at your general arrangement drawing No.4 I am beginning to understand how you are doing things nicely done so far harrypen Quote Link to comment Share on other sites More sharing options...
Wildfowler Posted May 15, 2013 Author Report Share Posted May 15, 2013 Hi harrypen Yes I know the pics are not always that clear (taken on my iPhone)! And please don't think I take any comments the wrong way, my last post was a bit rushed as I was on my way out... (I've just joined another fowling club ) I'm used to working in an environment where everything is challenged, that's how you tend to arrive at the optimum solution to a problem... With lots of input... I'm conscious it's not optomised, yet... And your point about the spring shoulder is a valid one which I'll incorporate if I can't find a more suitable spring. I have tried to consoder most aspects of it include the other points from yourself and catweazle but I'm sure there are claring issues that could be refined. If once I've made the action, I find that it could better, I'll make another one! It's only taken a few hours and I enjoy being out there doing it! The cost of those particular bits of material are insignificant really. Quote Link to comment Share on other sites More sharing options...
Wildfowler Posted May 15, 2013 Author Report Share Posted May 15, 2013 I did not understand fully the concept of the shell/breech and trigger mechanism but after looking more thoroughly at your general arrangement drawing No.4 I am beginning to understand how you are doing thingsnicely done so farharrypen Those are the original ones, Page 13, post 260 has more up to date ones. The breach hasn't changed but the action and trigger has. These are not how the final ones look but not too far off... Quote Link to comment Share on other sites More sharing options...
harrypen Posted May 16, 2013 Report Share Posted May 16, 2013 Durr I missed this ,,,,,,,,,,,,, also found the 2 videos on next page ,,,,,,,,,,,,,, now you turned the light on I can see ,,,,,, lol I spent a few hours this week and this morning revising the plans for the gun...Gun assembly2b.JPGGun assembly 2.JPG Quote Link to comment Share on other sites More sharing options...
harrypen Posted May 25, 2013 Report Share Posted May 25, 2013 I should point out at this stage that the last guns I built/assembled were 3 inch and 6 inch guns , as fitted to the likes of HMS Belfast which is now anchored in the Thames LOL but I do understand your design and build ideas respect harrypen Quote Link to comment Share on other sites More sharing options...
TIGHTCHOKE Posted May 25, 2013 Report Share Posted May 25, 2013 I should point out at this stage that the last guns I built/assembled were 3 inch and 6 inch guns , as fitted to the likes of HMS Belfast which is now anchored in the Thames LOL but I do understand your design and build ideas respect harrypen How old are you Harry? HMS Belfast was launched in 1938! Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.