Custom spring guides

[TonyL]

Indeed, Paul.

I also have a few rifles fitted with synthetic V-Mach items - still all going strong.

As indeed are the ones that I have fitted with the TbT and Welsh Willy items (as Pete says above) which have also been fine.

Seeing Nick's information on failure rate sheds good light on this.

And I suspect that a good proportion of those that did fail may have been down to other factors - insufficient preload being one of them, where the spring could pull the end of the guide away from the end block and then slam it back into the block.

[TonyL]

Yes, for the last seven years I think? One piece are ok, but are more prone to breaking, around 1-3% failure rate in our case. This was fine in the early days when we were only doing 100 or so kits a month, but now replacing 3% would be a nightmare to organize. The two piece guide has a very low failure rate, certainly sub 0.5%. most months we don’t see one.

If you watch the “What is a TbT kit” video on our website it goes into a little detail as to why this is.

Brilliant information; thank you.

[look no hands]

Indeed, Paul.

I also have a few rifles fitted with synthetic V-Mach items - still all going strong.

As indeed are the ones that I have fitted with the TbT and Welsh Willy items (as Pete says above) which have also been fine.

Seeing Nick's information on failure rate sheds good light on this.

And I suspect that a good proportion of those that did fail may have been down to other factors - insufficient preload being one of them, where the spring could pull the end of the guide away from the end block and then slam it back into the block.

That's an interesting thought Tone, I suppose the best guides would be the fixed ones, like fitted to the LGV/Century and the metal ones fitted by Venom to HWs.

[TonyL]

Yep, and guessing that's why some of the knowledgeable tuners went / go for a fixed guide, Pete. By the way, I can't take any credit for that theory and have seen it quoted on here a few times in the past.

[Shed tuner]

That's an interesting thought Tone, I suppose the best guides would be the fixed ones, like fitted to the LGV/Century and the metal ones fitted by Venom to HWs.

and fitted as std to the FWB sport 50 years ago

[Hsing-ee]

and fitted as std to the FWB sport 50 years ago

Talking of ye olde 20th century, I can’t remember but did Webley just drop the guide for the Hawk or Osprey? That would really make them ‘boingers’ as Tony affectionately calls springers…

[evert]

Talking of ye olde 20th century, I can’t remember but did Webley just drop the guide for the Hawk or Osprey? That would really make them ‘boingers’ as Tony affectionately calls springers…

Yep, just a little "knob" to center the spring on the rear block on the Hawk, and a small recess with a rubber disc on the Osprey.
An they carried on with the Tracker, using a cut down piece of the spring tamer plastic guide from the Vulcan, and just let it free-float inside the spring

Which reminds me that my Hawk deserves a new spring guide and a transfer port sleeve...

[look no hands]

Yep, just a little "knob" to center the spring on the rear block on the Hawk, and a small recess with a rubber disc on the Osprey.
An they carried on with the Tracker, using a cut down piece of the spring tamer plastic guide from the Vulcan, and just let it free-float inside the spring

Which reminds me that my Hawk deserves a new spring guide and a transfer port sleeve...

I have Welsh Willy kit here for an Xocet which I'm hoping will fit in my Tracker, they all seem to share lots of parts.

[evert]

I have Welsh Willy kit here for an Xocet which I'm hoping will fit in my Tracker, they all seem to share lots of parts.

Maccaris kit for the Vulcan/Xocet/etc fit the Tracker well. But a new spring kit never cures a problematic Tracker, they can have other issues as well.

[palace]

After Gerald Cardew fettled my Mk1 HW80 1982/3, John Knibbs came out with his Titan Accelerator spring made in Sweden close coiled for one & a half inches at one end with a blue ceramic coating I bought one from John it was too long spoke to john on the phone he sent me another cut & finished, I bought a John Bowkett long spring guide & power washers; about 30 years later during a quinquennial service I noticed the Bowkett guide was necking down a little about an inch up, the HW80 now sports a 2 piece TbT guide & top hat & washers & Bum Slide.

[Phil Russell]

I have always made single piece guides from delrin and have not had any failures to date. I have come across a failure though ... separated at the end. Also a guide where an unfinished spring end had ground its way through the guide body just in front of the flange.

But I keep telling myself I must make a 2 piece guide next time I need one ...Why? less wastage on material and because of comments on here. Question....if I made a 'bevelled' end flange and guide rod (tube), is there a recommended angle for the end flange. 45 degrees? 30 degrees?
I may well have one or two ex HW metal end flanges so guess I could copy that design.
Cheers, Phil

[Barryg]

I have two Tinbum kits and I am satisfied with both but my favourite is the one piece steel guide that Steve Pope made for me for my TX

[Dornfelderliebe]

In the old days they were a rolled tube split like a windmill for the flange , but the point is people still make them with a flange when they should use a countersunk head and once everybody knows and try it out for themselves they will see the light and the springer world will be a better place.

I've just opened up a Mk2 Meteor made as above with a slight radius where the washer will fit. The washer has been machined to a taper fit just as in the previous posts and as T20 says as Weihrauch do it, all be it with a metal washer/delrin guide.

The washer taper has the factory dark grey coating so it's not been done after manufacture.

[HW777]

That's an interesting thought Tone, I suppose the best guides would be the fixed ones, like fitted to the LGV/Century and the metal ones fitted by Venom to HWs.

That would also go a long way to explain why Diana thread their gas rams into the trigger block.

Which might be why some drop in gas rams work better in some rifles and poorly in others

[Born Again]

Regarding breakages of plastic guides, it's worth knowing that not everything sold as Delrin is actually Delrin. There are two closely related plastics, the homopolymer version (POM-H) is Delrin, a Du Pont trade name, the other is a copolymer (POM-C).

They have different mechanical properties but are often sold interchangeably.

POM-H is stronger in thin sections, more expensive, and suffers from porosity in the middle of large sections, as you might find in the middle of 25mm rod for example. POM-C has no porosity, can be more dimensionally stable, and is more chemical resistant.

Just to confuse matters more, Delrin is sold in different molecular weight versions named 100P to 900P.

Delrin is reckoned to be about 15% stronger and stiffer, and can take about 10% more load before creeping.