Jump to content
APC Forum

Recommended Posts

Posted

Hi all,

 

I have been deliberating about which press to buy lately. I have been thinking I've welding up my own frame and copying a H design press and tapping a bottle jack. Then in the end I thought I'll be spending as much time as this... http://bit.ly/19bxUEe whats everyone's thought on using that as my press.

Would be interested in everyone's opinion.

 

Kind Regards,

Jess

Posted

It looks like a good deal... looks very much like the Baileigh http://www.baileighindustrial.com.au/hydraulic-shop-press-hsp-10h

 

The problem with the Baileigh, is you don't have enough working room for 3 pound core burners. I do like that the frame is welded though.

 

 

I recently got the DAKE portable press, and it is "just" large enough to make 3 pound core burners with standard tooling.

 

http://i1149.photobucket.com/albums/o588/SaltLakeAreaPyros/20131210_104900_zpsf1613bb8.jpg

 

 

Any shorter, and I wouldn't be able to. I believe the Baileigh is around 2-3 inches shorter... so I would check the distances depending on what you plan to do with it.

Posted

Great, thanks mate. I was thinking when I move up to bigger rockets, I will just cut the bottom and weld on some extensions. But it will be enough for now.

I like how the gauge is already neatly on top and easy to mount a shield.

Posted

I've been thinking;

Would it be a good idea modifying these presses and welding to obtain greater stroke length?

Are they all reliably accurate in gauging?

 

Kind regards,

Jess

Posted

not quite sure what you mean by that could you elaborate

Posted
When I cut it and rejoin it to fit the bigger sizes. I am wondering if there are any complications as a result of doing that. Also, with the gauge is force applied always the same or do I need to make calculations based on size.
Posted

you only need to calculate for the surface area that the force is being applied to i.e. if you tap into a bottle jack you need to know the surface area the oil pressure is being applied to in your jack in order to know what pressure can be achieved with that ratio then you need to know the surface area of the rammer to know what pressure is being applied to the composition but the rammers and ram in the jack can be as long as they want and the pressures will still be the same the only complication you will have with extending a workshop jack is using the same quality steel and the welds being of the same or more strength

Posted

Beauty, I had just read somewhere and misunderstood that the rammer diameter affected reading of the gauge.

With the weld, when I need to move up in size I'll just do a real good job.

 

Looking forward to finally getting my press and will be so handy having it part of the setup.

Posted

http://www.ebay.com.au/itm/Workshop-Press-20-Ton-Air-Hydraulic-Side-Shift-Head-/231108692597?pt=AU_Car_Parts_Accessories&hash=item35cf26ca75

 

I just saw this one pop up on eBay, a little bit more but I think its got a few worthy bells and whistles. What does everyone think of the air attachment this has. Also has the ability to be manual jacked if compressor isn't going? 955mm working range compared to 330mm and 20 tonne.

 

Would love to know what people think. Thanks, Jess

Posted

if this is 20 metric tonns by 120psi compressor jessoman this set up seems wicked id be jealous by this setup

Posted (edited)

As far as I know it is 20 tonnes by the close-up diagram in the description. Not sure about the 120 psi thing. I wrote them a message asking what psi is required to achieve 20 tonnes, but I suppose that there are a few variables involved in that question. It doesn't say anything about what compressor is required. But it would sure speed things up with pneumatic actuation and perhaps safer with less movement on the press from 'jacking'

 

Cheap too...

Edited by jessoman
Posted

I've actually heard the opposite, that the pneumatic "can" create a ramming effect. I'm not sure if this creates a hazard though.

 

Either way, it looks like a nice press at a decent price. I don't have any complaints with pressing manually... it's actually pretty quick and easy. You eventually get a feel for how high to release the rammer to, minimizing the amount of pumps required to get the ram down to the tooling. I also use plates/spacers to speed up the process when there is a lot of travel needed.

Posted

Right, that makes sense too. I can imagine some pneumatic presses could get pretty aggressive so I'll just have to watch it. If not luckily I can always go manual.

 

Thanks for the advice. As soon as that guy gets back to me and all sounds goood ill order it and it will be here in a couple of days.

Posted

Beauty, I had just read somewhere and misunderstood that the rammer diameter affected reading of the gauge.

With the weld, when I need to move up in size I'll just do a real good job.

 

Looking forward to finally getting my press and will be so handy having it part of the setup.

The rammer diameter won't affect the reading on the gauge, but you will be applying a different amount of PSI to the composition with different diameter rammers than what the gauge shows.

This tutorial has examples of how to calibrate your pressure gauge so that you can read it for your press, then how to do the math depending on what diameter of rammmer\tooling\tubing you are using.

 

http://www.skylighter.com/fireworks/arbor-press-force-gauge.asp

Posted

Right, thank you. That's what I was wondering. If my press ram is 2 1/2 " and it's pushing a 1lb rammer of 3/4" I will have to do some maths. The gauge, is huge for 20T metric, I dare say I'll be drawing all over it.

I just got the press today. It's huge and solid. Manually jacking is super slow but ill work out a process.

Posted (edited)

20 tonnes on the gauge equates to 8963psi on a 2.5" ram. A gauge reading of 1 tonne will give you around 5000psi on a 3/4" rammer, 20 tonnes will be 99,600 psi ;)

Edited by Col
Posted

Thanks Col your a legend.

Okay, so my press ram is 45mm, so 1.7" so on a 3/4" rammer it would be ... Please show me the equation I have been reading thoroughly but I'm missing something.

Posted (edited)

On the actual gauge however it says 'RAM DIA60mm' however when I measured the actual ram on the press it's ~45mm

Hmm. Is this because the top of the ram/piston is 60mm (this is an assumption) in which case the bottom of the piston is ~45mm which means the gauge is incorrect and I need to work out that, then work out the rammer I'm applying? I want to be sure as I'm

New to this pressure/force/area thing.

 

Thanks in advance!

Edited by jessoman
Posted

Just use 60mm as your diameter.

 

Also, go easy on any nozzle mix your may use... they tend to get stuck pretty easily at very high pressure (from my experience).

Posted
Okay so if it reads one tonne on the gauge with 60mm onto the 3/4 ram what psi am I applying to the comp. I'm getting lost in the formulas...
Posted

Hi Jess

Your gauge is calibrated in tonnes/tons (not psi) so you dont need to worry about the ram diameter. If the gauge is calibrated to the press (assuming the designer did his job) you can simply take the gauge reading as weight,and apply it to the new rammer area and convert to psi.

If you use a 3/4" rammer and the gauge is reading 1 metric tonne, you have 2204 lbs on 0.441 square inches (19.05mm dia), 2204 / 0.441 = 4997 psi

Posted
Great Col, your brilliant. I understand completely now. I wish the gauge was bigger so I could read it a bit more accurate, I suppose as long as I keep it in between the 1&2ton marks. Not much room in between. I guess I'll get the feel for it! Time to make done tube supports ;)
Posted

consistancy is the thing, just hit the same mark on the guage everytime and you`ll be good.

Posted

 

Hey guys

 

I have a question, been just reading around for my new press and noticed a lot of people have installed shields in front of pressing area as wide as the press frame. But only from the top of the rammer down to as far as the press plate will go for whatever rocket. Even for presses 7ft tall. I'm just wondering if that's entirely safe. I was thinking the entire height of the press is best. But I may have steel 4ft high and a window of poly carb to see the action.

I'm just balancing safety and economy.

Posted

can you explain more jessoman or draw a pic

×
×
  • Create New...