Pneumatic or hydraulic press?

MikeVDS · Post by **MikeVDS** » Wed Jun 27, 2007 6:44 pm

For our 3/4" emt dome we used a pneumatic press that just barely did the job. This year for the big dome we're using galvanized toprail for fencing. We like nice clean rounded crimps so we need a press of some sort. The hunt has begun to find something cheap or Cheesy said he'll just buy one retail. I was wondering if anyone has any good ideas on how to save a little money.

Xtevan · Post by **Xtevan** » Fri Jun 29, 2007 7:31 am

The least manual labor would be a hydraulic press with either a hydraulic pump(electric or gas-think log splitter) or pnumatic booster pump. I have been thinking about this for a bit, I don't have the vacation time to drive to this years burn so dome building is on hold till fall.

A manual hydraulic press setup, press frame with bottle jack that has a manual pump is probably the cheapest route. But It will require at least a dozen or so pumping strokes per end crush. If you replace the bottle jack with one of the bottle jacks with the pneumatic pump(harbor freight had these on sale for $79 a while back) it would speed things up considerably and free both hands to hold the tubing(watch your fingers!!!).

The fastest way to knock a bunch of flat ends would be to build tooling to use with a hydraulic log splitter, an anvil base with radius to go on the fixed end and a matching die to replace the splitter wedge. If you could borrow or rent the splitter even better.

Xtevan

MikeVDS · Post by **MikeVDS** » Fri Jun 29, 2007 7:38 am

Thanks for the advise. I hadn't thought about a log splitter, I might know someone who has one locally. Harbor freight is probably where we'll go if we don't find anything cheaper.

gyre · Post by **gyre** » Fri Jun 29, 2007 8:33 am

What you want is known as a power hammer.

Charlie_in_OC · Post by **Charlie_in_OC** » Fri Jun 29, 2007 9:29 am

Mike

Not clear on what you are trying to accomplish.

Are you trying to flatten the end of the tubing? Or are you trying to bend a radius in the tubing?

Charlie

LeChatNoir · Post by **LeChatNoir** » Fri Jun 29, 2007 9:56 am

gyre wrote:What you want is known as a power hammer.

Big investment though.

I like the log splitter idea.

Other than that, as to what gyre is suggesting, you might try to find a local blacksmith in your area. Most established shops will have a power hammer of some sort and would probably be able to help you. When we made our dome, we set up our jigs and then turned it out in under an hour... sawed to the lengths, flattened, punched, and painted.

That was about five poeple.

Just for reference, I can forge 3" solid square stock in my 110 lb hammer (hammer head weight... anvil is about 800 lbs).

MikeVDS · Post by **MikeVDS** » Fri Jun 29, 2007 10:03 am

Not clear on what you are trying to accomplish.

Sorry about that. I'm just crimping the ends flat, but not along a straight line. So instead of having the crease along a straight line, it's a C shape so it's more difficult to bend. It's a pretty typical strut design for geo domes.

Charlie_in_OC · Post by **Charlie_in_OC** » Fri Jun 29, 2007 10:16 am

Mike

Lot's of good advice already posted, but if it's going to be used on the Playa, I'd look at using a Arbor Press:

http://www.victornet.com/productpages/a ... YQodg2uwUA

Hard to beat a mechanical design with very few parts to break.

Charlie

LeChatNoir · Post by **LeChatNoir** » Fri Jun 29, 2007 10:21 am

Charlie_in_OC wrote:Mike

Lot's of good advice already posted, but if it's going to be used on the Playa, I'd look at using a Arbor Press:

http://www.victornet.com/productpages/a ... YQodg2uwUA

Hard to beat a mechanical design with very few parts to break.

Charlie

Good suggestion. Flywheel press would work too.

capjbadger · Post by **capjbadger** » Fri Jun 29, 2007 10:34 am

Charlie_in_OC wrote:Mike

Lot's of good advice already posted, but if it's going to be used on the Playa, I'd look at using a Arbor Press:

http://www.victornet.com/productpages/a ... YQodg2uwUA

Hard to beat a mechanical design with very few parts to break.

Charlie

I've seen alot of reports of arbor presses not holding up to the job for long before starting to bend. I used a hydralic press and things went smoothly.

Badger

Charlie_in_OC · Post by **Charlie_in_OC** » Fri Jun 29, 2007 5:22 pm

Badger

What application were they being used in??

Only arbor press I've seen break was a cheap Harbour Frieght model that the cast body was full of porisity AND we were using a 4 foot cheater bar on the handle.

Charlie

[quote="capjbadger"][quote="Charlie_in_OC"]Mike

Lot's of good advice already posted, but if it's going to be used on the Playa, I'd look at using a Arbor Press:

http://www.victornet.com/productpages/a ... YQodg2uwUA

Hard to beat a mechanical design with very few parts to break.

Charlie[/quote]

I've seen alot of reports of arbor presses not holding up to the job for long before starting to bend. I used a hydralic press and things went smoothly.

Badger[/quote]

pbmaniac2000 · Post by **pbmaniac2000** » Fri Jun 29, 2007 5:25 pm

Are you just making the one dome? My suggestion would just be to find a shop to do it. We have a couple of metal/machine shops in town. I take stuff like that to them. Again i'm not sure on your scale, or if you are doing a bunch of domes.

MikeVDS · Post by **MikeVDS** » Fri Jun 29, 2007 7:38 pm

It's our second dome, the plan is to maybe make one more in the future. It's well worth it to do the pressing ourselves because of the time involved making around 250 struts, which means almost 500 crimped ends. In addition to crimping we'll bend the struts in the same step to about 8 degrees and we're using a custom bit to make the crimp (which means we'd need to design it to his machine or have him make it) also keep the different lengths sorted. By doing it ourselves we should easily cut the cost of some sort of press plus we end up with the press. We purchased our first press off of e-bay for about $70. It should operate up to 300 psi but our compressor only hits about 180. Another option would be to find a 300 psi source and see if that works.

Tried to call the guy with the wood splitter, he's out of town and we're building tomorrow.

capjbadger · Post by **capjbadger** » Sat Jun 30, 2007 9:57 am

Charlie_in_OC wrote:Badger

What application were they being used in??

Only arbor press I've seen break was a cheap Harbour Frieght model that the cast body was full of porisity AND we were using a 4 foot cheater bar on the handle.

Charlie

They were pressing EMT dome struts.

Iwent and borrowed a hydraulic press from a friend for my first dome, and recently bought my own for when I start work on the new one in the next year.

Badger

Charlie_in_OC · Post by **Charlie_in_OC** » Sat Jun 30, 2007 5:29 pm

capjbadger wrote:
Charlie_in_OC wrote:Badger

What application were they being used in??

Only arbor press I've seen break was a cheap Harbour Frieght model that the cast body was full of porisity AND we were using a 4 foot cheater bar on the handle.

Charlie
They were pressing EMT dome struts. Iwent and borrowed a hydraulic press from a friend for my first dome, and recently bought my own for when I start work on the new one in the next year.

Badger

Okay... Out with the Arbor press on onward with hydraulic presses.

I have Hyd. ram that started life as a Hyd. jack from a motorhome mounted on my tube bender, driven by the 12VDC pump scavenged from the same motorhome, think a similar design mounted to a press would make short work of EMT or fence post.

MikeVDS · Post by **MikeVDS** » Sat Jun 30, 2007 11:43 pm

Cheesy bought a used hydraulic hand press for $110, used. It smashed our stuff just fine and even smashed 1' schedule 80 pipe nicely. It's just going to be a lot of pressing. All the pieces are cut, but we need a couple things so we cannot start the long process of pressing until Monday night. I'll let you know how excruciating it is having to pump that thing 10,000 times, but at least it will get the job done cheaply and nicely.