Punch and Flatten Tube

  1. TechWise Member

    Messages:
    29
    Location:
    South Ayrshire, UK
    Going to be making some gates in the near future from 25mm x1.5mm round tube. I need to drill the ends for galvanising and flatten for welding to the uprights. I made a small batch before by flattening drilling on the pillar drill then flattening the ends in the vice. A very time consuming process.

    I will be making a larger batch in future of potentially 30 of them, so 8 bars a gate times two ends means 480 to drill and flatten. I'm wondering if it's possible to make something to do this faster? I'm aware of punch and die sets for flattening and punching the flat bit but that's not what I want. I need the hole to be in the bit that's still round so that the zinc can flow in and out.

    Someone suggested turning down some hardened digger pins I have to 22 mm to make the inner former then using a puch of some sort with a lever to punch the hole through the round tube. Is it feasible to do that?
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  2. frank horton

    frank horton V twins are great but 4"s rule.........

    Messages:
    2,230
    Location:
    Soon 2 B Crete
    do u have a bigish fly press ?
    unless u make the dies ur'self it will be cost prohibative I guess.......
    a complicated die for ur job will prob take longer to make than the job itself........
    then it has to be hardened for the hole punch then getting it to all line up.....phew......plus the other probs along the way......

    I need something similar except the hole would be in the flat part.....
    just gotta get the milling machine out from storage to make the dies......
    dont mind drilling the holes with a small jig tho....
     
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  3. johnser

    johnser Member

    Messages:
    2,132
    Location:
    North Cornwall
    Do the gates have to be designed like that?

    In my experience, flattened tube like that creates pockets which if drilled like you have won't explode when dipped but will result in potential trapped galve and uncoated corners.

    If the latter, eventually, all the rails rot at one end.

    Another way to get repeated good results is to notch the top and bottom of each end of the tube (as vent/drains) and weld to box section uprights. Have a look at an IAE gate to see what I mean. Saves squishing the pipes and I'd imagine is stronger too.
     
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  4. hotponyshoes Member

    Messages:
    3,398
    Location:
    Somerset. Uk
    This. With those holes where they are the backside of the weld is not going to get coated and this will be the place where damp will sit and the first place to rot.
    It would save you time as well as you could notch and flatten in one operation.
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  5. hotponyshoes Member

    Messages:
    3,398
    Location:
    Somerset. Uk
    Another simple way to do the ones above is use a tube notcher but use a size smaller than you should and you will get left a gap in the middle.
     
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  6. TechWise Member

    Messages:
    29
    Location:
    South Ayrshire, UK
    When I've done cattle gates, it's always been box section ends so there's no need to flatten the ends. I just V out the top and bottom and it turns out well. With these little sheep hurdles, we use a pipe bender to form the ends so that there's always a curved bit resting on the ground and they can be dragged around easily.I can't use box section for the ends because I need to use a pipe bender to form the ends.

    I like the idea of notching the sides and only flattening slightly as pictured. Using a pipe notcher was also briefly considered but seemed like a lot of effort for something that doesn't really need to be precise.
     
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  7. Shox Dr

    Shox Dr Chief Engineer to Carlos Fandango

    Messages:
    16,050
    Location:
    East Yorkshire
    Over kill, but an iron worker is made for this type of work
     
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  8. nickk Forum Supporter

    Messages:
    2,718
    Location:
    Hay-on-wye
    6A250FD9-E2FA-467A-A185-C8D33904CC33.jpeg 5CA58E62-4750-4393-AB02-01A92ADF088A.jpeg I had a small production of trollies ,so bought a notcher only for 3/4” but made a neat swift joint,if venting as said can easily notch a slot with a grinding disc,to a recommended size.
     
  9. TechWise Member

    Messages:
    29
    Location:
    South Ayrshire, UK
    Had a chance of one of those second hand a few years back :( The lathe was higher up the list unfortunately.
     
  10. TechWise Member

    Messages:
    29
    Location:
    South Ayrshire, UK
    Any info on where you got that? I wonder if I put a 3/4" notch in a 3/4" tube if it would leave a big enough vent when butted up against a 1" end piece.
     
  11. Shox Dr

    Shox Dr Chief Engineer to Carlos Fandango

    Messages:
    16,050
    Location:
    East Yorkshire
    Might work, more likely the Zinc would bridge it
     
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  12. nickk Forum Supporter

    Messages:
    2,718
    Location:
    Hay-on-wye
    Think it was WNS.
     
  13. gaz1

    gaz1 Member

    Messages:
    11,360
    Location:
    westyorkshire
    just seen this posted on site

    simple yet a very strong gate

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  14. KemppiFrog Member

    Messages:
    3,377
    Location:
    Aquitaine
    When making tube gates, I usually just drill the tube that the lower leg of the 'T' is glued too. Avoids visible holes. Leave the vent holes at the top and bottom of the gates, where they are less visible.
     
  15. tom2207 Member

    Messages:
    2,520
    Location:
    uk northern ireland
    I cant make gates as cheap as I can buy them ,,, so I dont even try. Strange how things seem to come round in circles though lots of gate parts are like that , balls and finials and leaves etc.
     
  16. tom2207 Member

    Messages:
    2,520
    Location:
    uk northern ireland
    our galve guys wouldnt dip them if they were made like that , they would drill extra holes and charge you a fiver a hole for the privileged od messing up some tasty work , been there before.
     
  17. KemppiFrog Member

    Messages:
    3,377
    Location:
    Aquitaine
    Yep, my lot charge for extra holes, but we have worked out what will flow and they are OK with internal vents on the 'middle' sections. Only time I got caught was with arches, where they required a hole atbthe top of the arch. Two holes and they did for free..
     
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