rose arch

[phil-s]

i have a pair of hydraulic rams with pumps i am trying to work out how to use one of them for making rose arches the rams are off some industrial entry gates ,any ideas for the second ramwould also be appreciated
thanks phil

[Jon]

Interesting question. I'm going to send this one out to our metalworking folks and see if we can come up with some answers for you.

[60jerry]

Phil, I've done no work with hydraulic rams, mostly because I haven't acquired any yet. Your question isn't all together clear to me. My main metal work is automotive and also just building smaller items. Are you wanting to use the extra ram in your current project or are you wondering about an additional use for that ram? If you want an additional use for it, I can say that I would use it for some auto bodywork, provided the ram isn't too large. Given a bit more time I would probably come up with other uses. Is it possible to post a picture of the rams and let me see them. I'm wondering if these need a hydraulic pump to operate them. The picture in my mind for using a ram is of one with a hand pump. Being commercial, this might be larger than my mind's picture.
Jerry in Denver

[awright]

Honestly, I do not see any useful application of hydraulic rams in fabricating rose arches. It would be very difficult to obtain the uniform curve necessary for a decorative object.

If I understand what you want to fabricate (an entry way to a garden consisting of vertical posts topped by a [usually] circular arc on which plants grow) I think you need a tubing roller like the Harbor Freight item #99736 ($180). This particular product is claimed to be able to roll up to 2" steel tube and may or may not work with the stock you plan to use but it shows the idea. There have been a number of posts on this site of tube rollers members have made "at home." If you want to roll square tubing you will probably have to rework the rolls or make your own to fit the tube. You do want to have smooth rollers that support the tube walls to prevent crimping and you must make the curve you want in very small increments to avoid crimping and to get the stock to pass through the rolls.

I have never used a commercial tube roller so I'm no expert on their capabilities. I did roll some 3 ft. steel hoops for my niece out of 1/2" square bar using two cheap ($2) steel rolls on a homemade slotted wood base with axles held in place with nails and using my lathe chuck as the center roller. Elevated the wood base incrementally with wedges. I don't recommend this approach with your lathe but it worked for me and the lathe survived. Just an example of how you can improvise a roller for a one-off job.

[Glueman2]

Not sure what you are trying to achieve here phil-s. If you are making an archway I think awright has the right idea with a tube roller. Are the rams in a pair? do you have a pump for each? If the cylinders are linked by hoses just remove the link and blank off the ports. Oh ! don't use brass plugs!

[C-Bag]

I'm with awright and Glueman2. I made a rose arbor with gate and used the above mentioned HF roller. I'm not sure how you would use the the ram you have but without rolling the tubing it will crinkle and buckle. I made my arbor out of 1" 1/8" wall square tube. They sell separate rolls for 3/4" square tube that I put in my lathe and machined out to take the 1". Making rolls for square tube is a lot easier than for round tube. I think the additional rolls were like $40, hard to make for that cheap.

The rams sound cool and I wish I had those for a big gate I've been gathering materials for.

[Frank S]

Maybe I am looking at this from a different perspective and am probably off in left field but it seems rto me that the Op may be asking how to fabricate a machine out of his ram to form the arch with if that is the case then more information of the ram and what materials it is that he is wanting to try and form would be needed before any assessment of how to use the ram would be needed
""i have a pair of hydraulic rams with pumps i am trying to work out how to use one of them for making rose arches the rams are off some industrial entry gates ,any ideas for the second ramwould also be appreciated""
Note his asking about using the 2nd ram to make something else
If he is wanting to use 1 of the rams as the power force then a bender similar to a Hossfeld may be 1 answer

[C-Bag]

You are right Frank. It's a little hard to know what exactly is needed, and why I waited for a while to jump in.

The more info up front the more folks can jump in and try to help. I'd not thought about a Hosfeld type bender, but you are right. Depending on the pressure output it might be a good way to power something like that. I've only seen those kind of benders, but my impression is you could make scrolls etc for the arch, but would it do arch itself?

[Frank S]

The arch itself would be made by a pyramid type roll wuth dies sized for the tubing angle iron "C" channel I beam etc that was to be used to power the roll again a cylinder could be connected to a series of bell-cranks and fulcrums and possibly sprockets &chains to turn linear motion into rotary motion this would entail losses of mechanical advantages or require a reversing ratcheting sprag & pawl to maintain the mechanical advantage while making the roll rotate in more than a short arc.
Or in the Hosfeld bender the arch could be made by making a series of very slight bends for example 30 6° bends would result in a 180° arch the distance or width could be anything from 1/2" per bend = 15" nominal arch to something like 10" per bend spaceing to = a 300" arch with small bends the arch would look almost circular