MEMBER ITEMS FOR SALE
Custom Knives | Other Knives | General Items
-------------------------------------------
New Posts | New PhotosAll Photos



Go Back   The Knife Network Forums : Knife Making Discussions > Custom Knife Discussion Boards > Knife Making Discussions > The Damascus Forum

The Damascus Forum The art and study of Damascus steel making.

Reply
 
Thread Tools Display Modes
  #1  
Old 04-23-2015, 10:05 AM
ss caustic ss caustic is offline
Member
 
Join Date: Jan 2015
Location: Canada
Posts: 17
forge press speed

the question is , how fast is too fast?

from your experience have you ever worked on or witnessed a press that was too fast?

I'm in the position to build a press for myself and through my research it seems speed is the key to getting the most out of your heat hence more efficient use of time/fuel and less material loss due to scaling etc...


just looking for what others think.
Reply With Quote
  #2  
Old 04-23-2015, 04:08 PM
Ed Caffrey's Avatar
Ed Caffrey Ed Caffrey is offline
Super Moderator
 
Join Date: Jun 2002
Location: Great Falls, Montana, USA
Posts: 4,393
Send a message via AIM to Ed Caffrey Send a message via Yahoo to Ed Caffrey
Yes.... I've worked on many different forging presses, and found that my taste leans towards a press that travels in the 1" per second range, or slightly slower.

I have to disagree with the "speed" thing.....a press is more about "precision" in forging. The unexperinced line of thinking often believes that you can just "squash" something in a press, and make shorter work of it....not true. Even if you have a high tonnage/high speed press, you generally don't want to take more then about a 1/4" "bite" at a time, otherwise if you try to move too much steel within a single "heat", you generally wind up causing things to get so far out of whack/control, that more times then not you just end up wrecking steel.
A press "forges" things differently then a hammer..... with a press heat is rapidly "sucked" away from the surface of whatever is being forged, and because the outsides that contact the dies cool quicker then the interior....a press basically forges from the inside out. A hammer, on the other hand, "strikes" the steel, and from the friction of the strike, keeps the surfaces contacting the hammer dies hot....which means a hammer forges from the outside in.

I often have people ask me why I own both, a forging press and an air hammer..... I explain it by saying... The press is my precision, and the hammer is my speed.

All that being said, I personally think that approx, 1" per second, or slightly less, is a good speed for a forging press.
If you're building your own, I also strongly suggest paying attention to the size of ram/cylinder you choose. Personally I think anything less then a 6" diameter cylinder is a bad idea.....because of the pressures created with smaller diameter cylinders. A pin hole in a line running 3000psi, will cut you in half like a light saber! I've been in other shops where guys who didn't know any better were running 4" cylinders, at pressures in excess of 4,000psi......thats a good way to get killed or seriously injured.


__________________
WWW.CAFFREYKNIVES.NET

Caffreyknives@gmail.com

"Every CHOICE has a CONSEQUENCE, and all your CONSEQUENCES are a result of your CHOICES."
Reply With Quote
  #3  
Old 04-24-2015, 10:51 AM
ss caustic ss caustic is offline
Member
 
Join Date: Jan 2015
Location: Canada
Posts: 17
thank you very much.

I likely worded my question poorly. I see now that what I should have said is , most want fast travel to to material and then slow down on contact so actual pressing speed is NOT fast at all but the contract time and not pressing travel time is FAST.

so with this in mind:

-I have a 6" cylinder with 10" stroke in mind.

-initially I was looking @ 16gpm@250psi - 4gpm@3000psi when run @ 3600rpm 2 stage and 5 hp 3600rpm 1ph 220v which would get me 1800psi max for the motor size and 25T or so from the press. should get me a fast stage time of 2.16 in/s and .54 in/s slow stage.

This is by far more economical in components but then I started to look at the next level #'s and was trying to figure out if it is worth the extra cash and if it was too fast or not.

-so next option was 22gpm@250psi - 6gpm@3000psi when run @ 3600rpm with a 7.5hp 3600rpm 1ph 220v motor. this would give me 2.9in/s in fast and .8in/s slow stage and and max pressure of 1800psi which is 25T or so.

-for 80$ more I can get a 10hp 3600rpm 1ph 220v motor which would get me 2500psi and 35T

choices, choices. having never used a press or knowing anyone who has one makes it tough...

thoughts:

1) should I use the buy once cry once philosophy and just pony up the extra 700$ or is the cheaper version enough the extra speed / pressure not worth it in the long haul.

2) separate question my supplier asked me is the type of hydraulic fluid/oil I wanted to use.
what are you using a hydraulic fluid or hydraulic oil system?

Last edited by ss caustic; 04-24-2015 at 12:18 PM.
Reply With Quote
  #4  
Old 02-17-2016, 07:47 PM
jph jph is offline
Skilled
 
Join Date: Jan 2003
Location: The wilds of the Florida Jungles
Posts: 312
Send a message via AIM to jph
Hello: Hope no one minds a new guy saying a couple things..I concur with EC..presses are nice but they can FUBAR your work PDQ if you are not careful. However when it comes to dimensional forgings they reign supreme if you use either kisser blocks or limit switches..plus if yours is designed with quick change dies there is a whole lit you can do with a press that would take forever to do by hand.

True they suck the heat right out of a piece..depending upon their size (I welds up faggots that are 1 1/4" square and 16 to 24" long) I can get two MAYBE three good squishes on a piece before it gets too "cold" to work. However used along with a power hammer the two really do work well with each other..

As far as peed goes..the use of a two stage pump will make things a lot smoother..the ram moves at a higher rate of speed until it touches the work..then the heavy stage kicks in and it slows down a bit to a more manageable speed..1" per second is a good speed for me under load..

JPH


__________________
Dr Jim Hrisoulas,
Author, Researcher, Swordsmith
Living in the Nevada desert.
N-T Hirsute Hine'y Hrisoulas
Reply With Quote
Reply

Tags
bee, build, building, choose, cold, dies, forge, forged, forging, hammer, hand, heat, hot, make, material, motor, power hammer, press, steel, surface


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Damascus press and forge WIP jdale The Newbies Arena 11 04-29-2013 10:01 AM
Hydraulic Press Ram Speed Bob Hartman Ed Caffrey's Workshop 21 11-15-2007 11:54 PM
Forge Press fbgraver62 Tool Time 4 11-02-2004 08:44 AM
Slow speed drill press, Such a thing??? nate d. Tool Time 2 09-11-2004 11:13 AM
Hydraulic Press Speed / Force for Damascus BrianT35 Tool Time 7 05-06-2002 06:22 PM


All times are GMT -5. The time now is 03:08 AM.




KNIFENETWORK.COM
Copyright © 2000
? CKK Industries, Inc. ? All Rights Reserved
Powered by ...

Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
The Knife Network : All Rights Reserved