Broken Treadle
Well unfortunately the weld on my treadle broke after a nasty fall to the ground due to the nylon rope I used to connect it to the drive shaft and the yelling of some choice profanity. after inspection it looks like the previous weld on this treadle never really boned to the cast iron in the first place so it maybe a good thing that I broke it before I was doing a long run of prints( but it was holding up fine until the nylon rope snapped). The problem is I currently have limited funds from just recently buying this press and new rollers/trucks, so I need to find a cheaper solution then just buying a new one from Hern. I have a good friend with welding equipment (Mig and acetylene) and I am curious if he can weld this with any of his equipment. I would also like to keep the treadle on during this operation because i don’t really feel comfortable taking apart the whole machine to remove the broken treadle or at least would rather not do that if I have to. If the weld wouldn’t be strong enough to take the pressure from treadling could I add some material on the bottom of the treadle to act as sort of a splint? It is a 8x12 NS Chandler and price and I am located in North Carolina. thank you for your help in advance.
Here is a photo of the broken treadle.
If your buddy can weld cast iron (typically oxy-acetylene) then you should be able to weld it back together. I would also suggest putting a reinforcement plate on the underside as well.
Here is a great resource over at Lincoln Electric on cast iron.
http://www.lincolnelectric.com/en-us/support/welding-how-to/Pages/weldin...
Actually I’d suggest the reinforcement plate should be shaped to the shaft of the treadle and welded, preferably brazed, on top, as that is where the tension stress will be and where the treadle will be most vulnerable to break again. But this won’t be easy to do on the press — it probably should be forge brazed to reduce heat stress on the rest of the casting. And get a proper hook made while you’re at it!
Bob
Thanks for the suggestions guys, Bob do you have the dimensions or possibly some photos of a NS 8x12 hook, I agree I need a real one of these!
I don’t have measurements but there really is no need to have an exact replica. Prop the treadle off the floor far enough to clear your toes, turn the flywheel until the crank on the shaft is straight down. Measure the center-to-center distance from the hole in the middle of the treadle to the center of the crank (half its diameter)(not the main shaft) and the diameter of the hole in the treadle. The hook shape and size should fit those measurements. I’d have a blacksmith make it out of minimum 1/2 inch rod. Make sure she knows the hook has to be a smooth even radius inside and the opening has to be at least the crank diameter.
Or maybe buy one from Hern Ironworks?
Bob
You should be able to Mig weld this (much less build up of heat). Weld in short bursts with time in between. The first weld will crack but metal will stick to the cast iron. The second burst will weld the crack back together and create a new crack. The process will continue: crack, weld crack together, new crack, until the piece is completely welded together.
Although I’d recommend the investment of a new treadle from Hern, I was able to fabricate one recently for a client in a rush. It was for a play - “Newsies” at the Paper Mill Playhouse in NJ - and the show had to go on; they could not wait the 7 days to get one from Hern.
I was able to make a perfectly functional treadle for an 8x12 C&P using a 2x6, 2 u-bolts and a shaft collar to hold it in place. There should already be one shaft collar on the back of the press, but a plumbing collar from Home Depot worked just fine for the other side.
The Hern treadle would be best, but if you can’t spring the $200 cost (treadle + shipping), or wait 7 days to get it, the 2x6 wooden treadle is a practical alternative.
Also - although I really don’t like the cast iron Hern hooks (preferring less brittle steel instead), I had one in stock and used it for this project.
I was prepared to fabricate one using1/8 x 5/8” cold rolled steel and believe that this would make a perfectly passable - and functional treadle hook. I will be doing this for my Kelsey Star one of these days and will publish a web page about it - with photos.
Just bend the lower end of the 1/8” flat steel to a closed loop that will go through a hole in your plank (the treadle) to hold a bolt or a shaft under the treadle, bend the upper end to wrap around the hook. Make this bend long long, since you may want to bolt it to itself rather than rely on the steel to hold the hook.
I also added a pair of old small press roller trucks on the ends of the bolt as “wheels” under the treadle. It made it run smoother
If you don’t have the steel or can’t bend steel in your shop, I could make one for you - but it would probably cost $30-50 plus shipping - and at my current schedule, would take me weeks to get to you.. But you can do it yourself - but forget that nylon rope - unless you protect the loop somehow - like maybe with a collar cut out of a soup can or something…
Have fun; be creative; print.
The welding of cast iron is a bitch , it requires preparation by way of pre baking for some hours usually and then welding with gas welder. I know as my father welded for many years and although it is do able with mig you cant put much load on it , the suggestion of pinning it with supports will however save you stripping the press again . That really being the only real choice you have ,I would speak to a good steam fitter ,welder i am certain they will concur.
Nylon rope? Really?