Big Al Posted March 16, 2017 Report Share Posted March 16, 2017 You can buy these type of jigs in the USA but I found I needed one this week and didn't have time to wait the 2-3 weeks for delivery. Ive done quite a few Howa bolts in the milling machine but a customer sent me a stainless bolt that was way too hard to cut using that method so it had to go in the lathe. Not a bad job for 3 hours work and I also managed a couple of bolt handles after. I find making good tooling that works is as satisfying as making a good job with it. I started with a length of 2" aluminium I had in the workshop, cleaned it off and then parted. I turned down one end to 1.5" so it would pass into my my spindle. A rough polish and thats the jig blank ready for the milling operations, overall length was about 7" You need to mill away enough material at the correct angle so it presents the bolt knob at the correct angle, this is important. The offset of the handle to the bolt was measured and then replicated here. This was to be a dedicated Howa jig so I opted to go for a split clamp arangement. This meant boring a hole big enough for the bolt lugs to pass through and then use a split collet to hold the bolt itself. Through hole bored to 1" Next I rotated the jig 90 degrees and put a flat on one side for the clamp bolt. An M6 tapping drill goes right through then a 6mm clearance drill follows it to half way. This gives clearnace for the bolt later. Counterbore and chamfer for the clamp screw. Splitting the clamp. A carbide slitting saw makes easy work of this task. Now its starting to look like something useful. I turned a collet to fit the jig and bored it to 0.684"ID which will hold the Howa bolt body. Split the collet on both sides. It was nice to see the calculations and measurements I made were good. The bolt has two planes of adjustment, it can slide in and out of the jig along its length and also it can be rotated which moves the handle up and down, both are used to find center. I will add some adjustable stop screws later which once set will mean there is no need to align the bolt each time but for now I just needed to get two bolts done. Threaded M8x1.25 The finished job. A final fix with Loctite and its ready to go. Link to comment Share on other sites More sharing options...
trucraft Posted March 16, 2017 Report Share Posted March 16, 2017 Nice job Alan. Very satisfying, making your on tools or something to solve a problem. Link to comment Share on other sites More sharing options...
jcampbellsmith Posted March 16, 2017 Report Share Posted March 16, 2017 Very nice, a good job well done. Best regards JCS Link to comment Share on other sites More sharing options...
Ronin Posted March 16, 2017 Report Share Posted March 16, 2017 How do you support the bolt handle to prevent the soldered handle parting from the bolt body? Link to comment Share on other sites More sharing options...
Charlts Posted March 16, 2017 Report Share Posted March 16, 2017 How do you support the bolt handle to prevent the soldered handle parting from the bolt body? Howa bolts are fairly substantial, would it make much of a difference? Link to comment Share on other sites More sharing options...
Big Al Posted March 16, 2017 Author Report Share Posted March 16, 2017 How do you support the bolt handle to prevent the soldered handle parting from the bolt body? The adjustable stops will give support to the handle itself when I fit them. Looking at the contact area that has been soldered I would expect it to be more than strong enough on its own as its a very different design to the small contact area of a Remy, in fact I dont think it would ever come loose as the bolt handle is sleeved over the bolt then hard soldered so will resist rotational torque as a result of the design. Then again but support is never a bad thing in machining so a belt and braces approach wont hurt. Have you seem many Howa bolt handles come off in this way? Link to comment Share on other sites More sharing options...
6.5 shooter Posted March 16, 2017 Report Share Posted March 16, 2017 Nice engineering skills! Link to comment Share on other sites More sharing options...
The_Dogge Posted March 16, 2017 Report Share Posted March 16, 2017 Very nice bit of engineering. The new bolt handle though, to me they are just unnecessary weight which do nothing for the ergonomics of the rifle. There was one on a Sako 75 I bought and IMO it actually stopped the bolt working properly, it seemed to jam due to the extra leverage trying to force it sideways. I took it off and replaced it with a plastic ball, which may not look as fancy but functions 100% better for me. They form a natural ball and socket joint with your hand, I don't know why more people don't use them. Am I missing something about what these handles are for? Whatever you want to do with it I suppose you need to start by threading it though, so I don't mean to sound like I'm criticising your work! :-) Link to comment Share on other sites More sharing options...
Big Al Posted March 16, 2017 Author Report Share Posted March 16, 2017 Very nice bit of engineering. The new bolt handle though, to me they are just unnecessary weight which do nothing for the ergonomics of the rifle. There was one on a Sako 75 I bought and IMO it actually stopped the bolt working properly, it seemed to jam due to the extra leverage trying to force it sideways. I took it off and replaced it with a plastic ball, which may not look as fancy but functions 100% better for me. They form a natural ball and socket joint with your hand, I don't know why more people don't use them. Am I missing something about what these handles are for? Whatever you want to do with it I suppose you need to start by threading it though, so I don't mean to sound like I'm criticising your work! :-) No criticism taken, these bolt knobs are not for everyone and as you say, whatever shape you want it needs to start with threading. Link to comment Share on other sites More sharing options...
Ronin Posted March 17, 2017 Report Share Posted March 17, 2017 The adjustable stops will give support to the handle itself when I fit them. Looking at the contact area that has been soldered I would expect it to be more than strong enough on its own as its a very different design to the small contact area of a Remy, in fact I dont think it would ever come loose as the bolt handle is sleeved over the bolt then hard soldered so will resist rotational torque as a result of the design. Then again but support is never a bad thing in machining so a belt and braces approach wont hurt. Have you seem many Howa bolt handles come off in this way? My jig supports the handle base to prevent rotational twist of any machining load. Never had any break off. Though had to repair / replace several bolt handles broken by heavy handed users who insist on "reloading" beyond their skill set.......... Link to comment Share on other sites More sharing options...
johnnyb0_1 Posted March 26, 2017 Report Share Posted March 26, 2017 A very interesting and informative post. Thanks for posting. PM sent also. Cheers. JP. Link to comment Share on other sites More sharing options...
RPA 6mm BR Posted March 26, 2017 Report Share Posted March 26, 2017 How much do you charge for this Alan and how long is the turn around? Link to comment Share on other sites More sharing options...
Big Al Posted March 26, 2017 Author Report Share Posted March 26, 2017 How much do you charge for this Alan and how long is the turn around? £75 which includes return postage, turnaround is usually a couple of days, sometimes it can be done same day depending on my workload. Link to comment Share on other sites More sharing options...
RPA 6mm BR Posted March 26, 2017 Report Share Posted March 26, 2017 £75 which includes return postage, turnaround is usually a couple of days, sometimes it can be done same day depending on my workload. Ok many thanks, I will be in touch soon for you to do mine Link to comment Share on other sites More sharing options...
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