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Bret4207
05-07-2007, 08:31 AM
I am the proud (??) owner of a couple Frazer Rototillers, circa 1930-60. You used to be able to get spring tines and holders from the now defunct Frazer Farm Equipment Co. Ebay tines and holders go for about the price of a barrel of oil, each!, and there are something like 13 tines and 13 holders so it runs to money. The material is 3/8 or 7/16 round stock, and it's a spring material that can stand picking up a football sized rock and flinging into your shins at about 25 mph. They also have to have good wear quality and be capable of taking hard facing rod build up if possible. Beyond building the jigs to form them, what am I looking at as far as type of material and heat treating?

Buckshot
05-07-2007, 11:50 PM
I am the proud (??) owner of a couple Frazer Rototillers, circa 1930-60. You used to be able to get spring tines and holders from the now defunct Frazer Farm Equipment Co. Ebay tines and holders go for about the price of a barrel of oil, each!, and there are something like 13 tines and 13 holders so it runs to money. The material is 3/8 or 7/16 round stock, and it's a spring material that can stand picking up a football sized rock and flinging into your shins at about 25 mph. They also have to have good wear quality and be capable of taking hard facing rod build up if possible. Beyond building the jigs to form them, what am I looking at as far as type of material and heat treating?

............Howze about torsion bars from the junk yard? Tough stuff! Lots bigger then 7/16" though. Maybe old leaf springs? It's not round through. My grandfather used them to weld on at new tips on his springtooth harrow.

................Buckshot

Four Fingers of Death
05-08-2007, 12:44 AM
Have you checked around the blacksmith's in the area. A fellow Corrctional Officer retired early and when back to smithing to produce tynes and chiselpoints for old plows and seed drills, etc. Not enough volume for the big guys, but keeps his power hammer singing.

chevyiron420
05-08-2007, 01:32 AM
i would probably try drill rod.-phil

grumpy one
05-08-2007, 01:43 AM
Unless you get lucky you'll need to find coil springs with the right wire diameter and rework them. Might be something in the way of motorcycle springs would be about right. Then you need to anneal them, form them into what you want, and heat treat them. That forming stage might include some forging work if you don't want them to be circular in cross section.

The heat-treating is a bit of a black art, and if you have a local spring-works it is probably best to get them to do it. Otherwise you have to heat the stuff to red-orange, quench in water, then temper. The tempering is the main black-art stuff. You make up some spares, and temper them experimentally, then try them for real. If they break, you didn't temper them enough. If they bend, you tempered them too much. Try to read the colour of each try-out, so you can reproduce it.

If you get a spring works to do it, you shouldn't have all that tempering hassle and life will be quite a bit easier.

I wouldn't bother to try anything but spring steel - you'll only waste your time.

leftiye
05-08-2007, 03:51 AM
Polish (get bare metal) and temper to a blue color. Only problem is quenching in the right medium, I'm not sure, but oil sounds right. Grumpy's right only spring steel is worth messing with.

exblaster
05-08-2007, 10:41 AM
Torsion bars from the hood not the suspention might work.
Exblaster

John-n-va
05-08-2007, 11:57 AM
I make spring steel "privy probes" for antique bottle hunters as a sort of side business. Keeps me supplied with black powder. I use the torsion springs that hold the trunk lids open on those big ole boats we used to drive. Chrysler products in the 60's and 70's had big ole rods about 4 feet long and about 3/8" dia. Two in each trunk that crisscross each other.

You gotta be careful removing those things as they are under a ton of pressure and will smack a big knot on your head. I use a BIG screwdriver and pry one end loose and then work the other end loose. Also make sure you prop the trunk lid open before removal. The lid will also smack a knot on your head on the way down. I know all this from experience!

My junk yard charges me $2 apiece if I remove them.

BeeMan
05-08-2007, 04:08 PM
About a month ago I straightened out about 30 inches of coil spring for knife blade stock. It was right at 7/16 diameter. I used a home built propane forge and a section of railroad rail for an anvil. After forging, I air cooled so the blade blank was soft for finish work. Got busy elsewhere and haven't tackled finish or hardening yet.

It better be a labor of love if you want to make a bunch of tines for your tiller, but I have no doubt it can be done.

BeeMan:redneck:

KCSO
05-08-2007, 08:40 PM
Find an old dump rake in a scrap yard and you will be in business. Dump rake teeth work real well and yo won't have a lot of shaping to do and they are real easy to retemper.

Hackleback
05-08-2007, 09:22 PM
I think that KSCO hit the nail on the head!

RayinNH
05-08-2007, 10:27 PM
Tpr. Bret, KCSO is correct. As a person that did professional smithing for about 20 years this is not a job for a beginner. In fact it's not even a job for your typical smithing shop. To get the desired results these tines would need to be heated their entire length evenly from one end to the other before quenching to harden. Then the temper needs to be drawn evenly. The average blacksmith forge won't heat anything that long, evenly. You'd end up with sections that are hotter than other sections. The hotter sections if too hot would probably break. The cooler sections would most likely be too soft, would bend and stay bent.
The amount of time and trial and error involved would make that price of a barrel of oil per tine start to look like a pretty good deal.
If this doesn't deter you then for goodness sake have a heat treating company do the heat treating for you. Spring steel is the only suitable material for this...Ray

Bret4207
05-09-2007, 08:03 AM
http://www.e-rototiller.com/maintenance/partsbook/partsbook-page23.shtml

www.e-rototiller.com

Thats a link to a pic of the tines and spring time holder and to the main website of the collectors assoc. These are a very HEAVY DUTY version of what became the Troy Built type design. I have no problem BUYING the correct stock to form the spring holders and tines and taking it to a spring house for proper heat treatment. I suppose I'm asking for recommendations on material to buy for best results.