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17-4 PH source

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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azspearo

New Member
Dec 15, 2004
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Looking for 3/8, 5/16, 9/32 & 1/8 17-4 PH hardened rods. Anyone know of a good source besides McMaster Carr?
Also what is a good spring steel for spear shafts.
Looking to make some low cost shafts and paralyzer tines.
Aaron
 
You need to make the Thermal treatment for increase the hardness after the machining, so buying already hardened rods you do not win anything.
 
You should not buy hardened steel (don't think you can even find it) as you will not be able to machine it and will loose the hardened properties after you weld the fins. You have to purchase annaeled 17 - 4PH machine it, weld it and then heat treat it to H900 to get RW hardness of 43 to 45.

Do a search on internet and you will find tons of suppliers that sell the rods anywhere from $18 to $30 each. Some of them require a minimum order, others don't.

There are a whole bunch in the Houston area.
 
I can machine H900 with carbide. I'm making some shafts for some Halibut pole spears with a single flopper and just need to drill one hole.
The 9/32 is for Euro style shafts and I won't be doing any welding. I guess I should of put this in my post.

H1150 machines the best and would look for that if I was going to be making some shafts with fins.
Thanks for the quick response.
 
Hi Alex,

I have the same problem, I can find 8 mm stainless steel in Thailand, but it is too soft and after 2 or 3 fishes I have to make another one. DO you have more info on the Thermal treatment to harden the SS? What Temperature? How long? any risk to losse the SS property?
Thks in advance
 
The first shafts I made I didn't heat treat because I only made 5. With almost every large fish (tuna) I caught I had a pretty bad bent shaft.

The second time I made a whole bunch of shafts for my brothers, a cousin and for me.

To make life easier I machined the slip tip back into the shaft and only purchased the tip, cutting expense and eliminating weak spots (thread).

Once the ss was machined and welded, I found a heat treating plant here in Mexico City and spoke with them, but they didn't have the slightest idea what I needed, so with a little research on internet I found that the process which gives 17-4PH the best hardness is H900 which means the steel must be heated to 900 degrees farenheit for one hour and then air cooled.

I was charged something like US$3.50 per kilo and they even tested that the shafts had aquired the maximum harness.

I still haven't shot big tunas with any of these shafts so couldnt tell if they will hold straight after a fight, but they do feel more rigid.

If I didn't answer your questions just let me know and I can direct you to the information sources, but you should be able to get by just dooing a search of 17 - 4PH on Internet.
 
Hi Alex,
thks so much for the info, I need to find a company that can make heat treatment.
Your solution for the slip tip puzzled me, can you explain me how you machine it? My solution is to order the tip only (JBL3" or 4") and I enlarge the hole to fit a 7mm shaft. The other thing to solve the bent sfat problem (but I never test it) is to use a slide ring on the shaft, the reel line through the slide ring and directly linked to the slip tip . In that case all the strength of the fish is applied on the cable but not on the shaft no risk to bend it. My concern is the accuracy. if u come to asia lets shot some fishes and beer!:friday


thks and tropically yours at www.koyaobay.com
 
The machining of the tip is easy on 8mm shafts as you only have to make the oring groove so the tip doesn't fall off. I just copied the back of the JBL 4" slip tip and purchased the tip. The hole for the cable is made in the shaft.

The bending problem is not fixed by attaching the line to the tip, the shaft is bent the moment it goes into the fish. When the slip tip starts pulling the floats, the shaft is already bent.

With large groupers I have seen that the moment the shaft goes in, the fish either bangs the shaft against rocks or just twists and turns and the friction with the water bends the shaft. With tuna, I believe it's the friction with the water that bends the shafts, but it's also before the shaft is pulled out by the floats.

Tuna season here will start very soon, so I can hopefully test my new shafts.

The ring on my shafts don't work because there's nothing to stop it at the end.

Here's a close up of the shaft's tip, this shaft is 3/8, so I had to reduce the diameter a bit, but with 8mm shafts you only do the very tip and the oring groove.

If you need a photo of the 8mm shaft without the oring let me know and I will post it.
 
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if your getting 42-45 rc, then i still believe that you have a very weak shaft.. back when i was making knives, i was getting them somewhere in the mid to high 50's, and they would still bend before they snapped, but they didnt bend very easily.. at least 4 times as stiff as my spears that i get, of course, they were not stainless steel, but im sure that there is a good steel out there for making shafts, which can be heat treated to about 52 rc.
 
HI Alex
Thks for all advises, my only problem is that I down have all the machinery you have but I ll try to find. Thks also for the tip to harden SS. I ll made my own oven later on.
Tkae care buddy,
 
depends on where you live, id reccomend looking for a metalworker who is experienced in thermal cycling steel, stainless steel is extremely picky, and to build a kiln that could handle a full shaft would be a bit difficult, because of heat differences along the length. if you did want to try it yourself, id suggest a piece of 2 foot diameter or so steel pipe, fill it with a good insulator like satanite (can get hot as hell ) and do some searches for how to evenly spread the heat. (propane burners along the whole length come to mind)
 
HI Buggy
Tks for the reply and advise, well I dont know any good experienced guy that can make good thermal treatment, but I have been working for a RD lab for steel and metal teatment, I will follow you idea with the steel pipe, but procurement of insulating matrerial should be a problem. A cast iron pipe can accept higher temp than 482deg C , and need to use burner O2 and ethane to reach easily the right temp, need also to put a fan sustem to keep the same temp all along the pipe.
Ill let you know the result
bye and thks agaIN
 
Your problem is going to be keeping a constant temperature over the whole shaft and also keeping accurate readings so you keep the temperature at the 900F in the pipe core. If you go higher, the hardness goes down, if you don't get to that temp, same thing happens.

I found the plant in the yellow pages, explained what they had to do and got great results.

Alex
 
if your having problems finding insulating materiel, its worth noting that one of the best insulators out there is plain old ash from the bbq just make sure its not full of fat drippings even tho that can give your furnace a nice smell the first time u light it.. i know some guys that mixed ash with clay powder and got very good results too
 
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