Broken Platen Back

Hi BriarPress Community,
I’m writing to you to see if you could help me out with my Kelsey press. Within the past year, I’ve purchased a Kelsey 5x8 press, purchased new parts and cleaned and refurbished existing parts. This weekend, while printing for only my second time, the back part of the platen broke. I’m not sure if I was exerting too much pressure or if there was an existing hairline fracture that I wasn’t aware of, but I’m basically stuck and cannot print.

Can anyone recommend the best way of moving forward to repair my press? Should I look to replace the back piece all together or could I get away with welding the piece back together? Any advice you can lend is greatly appreciated. Thank you.

image: DSC00841b.jpg


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I would contact Alan at Excelsior Press in New Jersey, he has some parts for these presses, i don’t think you can repair this with any success. Good Luck Dick G.

B- That type of break is the typical failure mode for a 5x8 when the platen is not adjusted correctly, and then overstressed badly. What happens is that all of the pressure concentrates on that one corner, and snap!

A few years ago I tested a 5x8 to destruction with strain gauges to see how much pressure they’ll actually take…. and the break occured almost exactly like yours did. The results are posted here on Briar Press if you are interested in looking them up. The little presses are actually quite sturdy, so yours may have had a flaw, or possibly an old stress crack that finally let go.

As far as repair goes, I’d recommend replacing the part if you can find one. Call NA Graphics or Excelsior Press.

If you can’t find the part, you can have it welded or brazed back together. BUT if you do, you need to have it done by someone familiar with Cast Iron. Just any old stick or mig welder will not do a proper job of it. I’d find someone who repairs cast-iron engine blocks and let then do it. The part needs to be pre-heated, repaired and then cooled correctly or it’ll just break again.

Good Luck.

It seems like a classic case of the wrong press for the wrong job. I’m presuming the machine was being used for Deep Impression. The position of the break reveals how thin is the paper platen in that place, also the lack of physical support behind that area for any excessive impression. Most standard presses are designed for the kiss impression action. Design and lockup should concentrate in the centre where there is some semblance of support. The rest of the area of the paper platen is usually just for the support of the paper. Another place to keep watch is the platen conrods and the bushing that is always under tremendous strain, even with the most delicate of impression. The castings and bushes can crack or break quite expectedly. To re-connect the broken part will require a good tradesperson making sure the platen is perfectly flat and there are no seams to hinder a clean impression. There are stronger sturdier and often specialized machines for the excess impression required. The amount and area of impression is relative to the size and bulk and intention of the press.
The operator needs to understand that most standard, older platens and some cylinder presses were not made for the demands expected to day. Buyer beware.
See Letterpress 101
William of Rockley, NSW

look at the break area. if it is all a nice sparkly granulated look to it, it broke all at once. if there any dark areas as if something, which did, soak in, then there was a hairline crack present. i have had great success with a local vendor who “stiches” cast iron. you can look it up. it works great and being a cold process, final alignment is much closer. these guys are experts at fixing cast, but in milwaukee. so now you would have price plus shipping. it might somewhat cheaper the longer you want to wait. i am trying to find the pics of a14x22 kluge bed leg repair. still running after 6 years.