Need advice on Presses, Arbor or hydrolic ?

[h&k machineguns]

Hello all, this is my first post so please bear with me.

 

I'm about 4 months into making rokets and have a lot to learn. I just found this forum and am excited that there are others that I can come to for answers,and not have to keep bugging Richard Wolter(Wolter tooling) and Gary from Firefox for advice.

I have the harbor freight 12 ton press. I have been thinking of selling it,and buying an Arbor press instead. They seem like they would be so much faster than the hydrolic presses and seem to take up less room in the garage. I have used my press so far with the 1 pound core burer BP rockets and lately the 4 oz rockets for both BP and whistle. I'm not sure though what ton press I need for what I'm doing is. I usually just stop pressing once my PVC/Hose clamp sleave starts making creeking noises. I often wonder if I could press more,or if I'm pressing to much on these rockets.

I plan in the future to make bigger rockets. Do they make a arbor press that will do the big boy rockets ? Should I just stick with the 12 ton press that I have now ?

I also wonder if the little 3/4" metal rod that comes down on the press on my rocket is suppose to be perfectly straight in verticleness. Mine seems to be off a little. My rammers also tend to sometimes end up angling inside the rocket tube. I'm not sure why this happens and if it's because of the uneven press,or something I'm doing wrong.

Thanks

[pyrochris]

Hello all, this is my first post so please bear with me.

 

I'm about 4 months into making rokets and have a lot to learn. I just found this forum and am excited that there are others that I can come to for answers,and not have to keep bugging Richard Wolter(Wolter tooling) and Gary from Firefox for advice.

I have the harbor freight 12 ton press. I have been thinking of selling it,and buying an Arbor press instead. They seem like they would be so much faster than the hydrolic presses and seem to take up less room in the garage. I have used my press so far with the 1 pound core burer BP rockets and lately the 4 oz rockets for both BP and whistle. I'm not sure though what ton press I need for what I'm doing is. I usually just stop pressing once my PVC/Hose clamp sleave starts making creeking noises. I often wonder if I could press more,or if I'm pressing to much on these rockets.

I plan in the future to make bigger rockets. Do they make a arbor press that will do the big boy rockets ? Should I just stick with the 12 ton press that I have now ?

I also wonder if the little 3/4" metal rod that comes down on the press on my rocket is suppose to be perfectly straight in verticleness. Mine seems to be off a little. My rammers also tend to sometimes end up angling inside the rocket tube. I'm not sure why this happens and if it's because of the uneven press,or something I'm doing wrong.

Thanks

you can get some very nice, small arbor presses here for a pretty decent amount, even though its in the U.K, its still fast shipping.

http://www.axminster.co.uk/sessionID/YZQ/r...ress-362981.htm

[cplmac]

If you're ram is getting cocked inside the tube it sounds like you might be using a ram that is to small for the tube. I have used an arbor press for small rockets (<1lb.). If you plan on making rockets bigger than your 1 pounders I would recommend using the press. And it is a good idea to press as perfectly vertical as possible. It presses your comp more evenly, and helps prevent damage to your tooling and motor.

[ActionTekJackson]

Okeedokee, this isn't the first time I've seen a Harbor Freight press mentioned. Now, I get a Harbor Freight catalog every two weeks, and I've checked it and their website for this several times... still can't find it. Do they call it something else or am I just completely blind?

[Frozentech]

Okeedokee, this isn't the first time I've seen a Harbor Freight press mentioned. Now, I get a Harbor Freight catalog every two weeks, and I've checked it and their website for this several times... still can't find it. Do they call it something else or am I just completely blind?

They are commonly called a "shop press"

 

Here is the model I have:

 

12 Ton Shop Press

[h&k machineguns]

If you're ram is getting cocked inside the tube it sounds like you might be using a ram that is to small for the tube. I have used an arbor press for small rockets (<1lb.). If you plan on making rockets bigger than your 1 pounders I would recommend using the press. And it is a good idea to press as perfectly vertical as possible. It presses your comp more evenly, and helps prevent damage to your tooling and motor.

So your saying an Arbor press is good for making rockets bigger than 1 lb ? I think that's what I got from your post. Thanks

 

Is the Arbor press much faster than the hydrolic bottle types ?

[Mumbles]

An arbor press is better for smaller rockets. I don't think you could even fit a 1lb rocket in there unless you have a 3 ton arbor press. I would say keep your hydraulic press, well unless you want to donate it to me You'll need it for larger rockets, and whistle rockets any bigger than 2oz probably. A 3 ton arbor would be needed for a 4oz whistle. A press can never be too big or powerful. You don't always have to put full pressure on it.

[h&k machineguns]

An arbor press is better for smaller rockets. I don't think you could even fit a 1lb rocket in there unless you have a 3 ton arbor press. I would say keep your hydraulic press, well unless you want to donate it to me You'll need it for larger rockets, and whistle rockets any bigger than 2oz probably. A 3 ton arbor would be needed for a 4oz whistle. A press can never be too big or powerful. You don't always have to put full pressure on it.

That was exactly what I was looking for,thanks

 

How do you know how much pressure is enough,or to much ?

 

Wolter has the little gage thing,but it's as much as I spent on the 12 ton press. Any cheaper models out there that will work ?

 

http://www.wolterpyrotools.com/pyrotools/rockettools.html

[Frozentech]

That was exactly what I was looking for,thanks

 

How do you know how much pressure is enough,or to much ?

 

Wolter has the little gage thing,but it's as much as I spent on the 12 ton press. Any cheaper models out there that will work ?

 

http://www.wolterpyrotools.com/pyrotools/rockettools.html

Another way to measure your loading pressure is to drill and tap a hole into the hydraulic jack, and insert your own gauge. It might save a few dollars, but a lot of people won't feel comfortable doing this.

 

Also, if you do go with a gauge measuring hydraulic pressure, you will have to calculate your pressing force from the hydraulic pressure, ram diameter, and tooling diameter. The Woltor guage is calibrated to 1 square inch, so your pressure is directly readable in PSI.

 

I don't have a handy reference for loading pressures, but 6000-6500 psi force is usual for BP rockets, up to 8,000 for whistle fuels. As far as how much is too little or too much, the goal is to consolidate the fuel into a solid grain with no voids or cracks. Too little pressure will lead to a CATO, too much will split or bulge your tube.

[h&k machineguns]

That was exactly what I was looking for,thanks

 

How do you know how much pressure is enough,or to much ?

 

Wolter has the little  gage thing,but it's as much as I spent on the 12 ton press. Any cheaper models out there that will work ?

 

http://www.wolterpyrotools.com/pyrotools/rockettools.html

Another way to measure your loading pressure is to drill and tap a hole into the hydraulic jack, and insert your own gauge. It might save a few dollars, but a lot of people won't feel comfortable doing this.

 

Also, if you do go with a gauge measuring hydraulic pressure, you will have to calculate your pressing force from the hydraulic pressure, ram diameter, and tooling diameter. The Woltor guage is calibrated to 1 square inch, so your pressure is directly readable in PSI.

 

I don't have a handy reference for loading pressures, but 6000-6500 psi force is usual for BP rockets, up to 8,000 for whistle fuels. As far as how much is too little or too much, the goal is to consolidate the fuel into a solid grain with no voids or cracks. Too little pressure will lead to a CATO, too much will split or bulge your tube.

Kinda off the topic ,but I had a 4 oz end burner BP rocket(No payload or rocket body just a 3/16" wood dowl about 18" long) the other day take off at around 10-15 MPH and kept a steady speed to about 50 feet high then it slowly returned down to the ground on the other side of the house.I'm betting I couldn't make a rocket like that again if I wanted to.

I'm guessing I didn't press that rocket motor down as much as it could have been. I wonder if I should just bite the big one and buy the Wolter gage?

 

Also how new is this board ? It doesn't seem to have history going back very far on the rocket section.

[Frozentech]

Kinda off the topic ,but I had a 4 oz end burner BP rocket(No payload or rocket body just a 3/16" wood dowl about 18" long) the other day take off at around 10-15 MPH and kept a steady speed to about 50 feet high then it slowly returned down to the ground on the other side of the house.I'm betting I couldn't make a rocket like that again if I wanted to.

I'm guessing I didn't press that rocket motor down as much as it could have been. I wonder if I should just bite the big one and buy the Wolter gage?

 

Also how new is this board ? It doesn't seem to have history going back very far on the rocket section.

The first stinger style rocket I made sorta freaked me out, it spun up, then lifted off it's launcher, hovered just about 8 feet in the air and sorta started drifting toward me at a steady height. Looked like some alien space probe thing from Star Wars or something. It then burned out, and flopped to the ground... That was definitely caused by not hot enough propellant for the style of rocket ( stingers can use much hotter RP than a full length core burner )

 

If you are going to get serious about BP rocket pressing, I wold recommend the gauge if you can afford it. Other people have learned through trial and error how much to press 'by feel' with thier presses. ( one friend says "till it squeaks" )

 

The age of the board ? I dunno the total age, but all the posts here are from the current incarnation of software. When they switched to Invision Power Board about a year ago, the older posts got left behind. Mumbles used to post the address of the old board in his signature, you could ask him for it, I do believe it's still there, just can't post anything new to the old forum.

[ActionTekJackson]

Okeedokee, this isn't the first time I've seen a Harbor Freight press mentioned. Now, I get a Harbor Freight catalog every two weeks, and I've checked it and their website for this several times... still can't find it. Do they call it something else or am I just completely blind?

They are commonly called a "shop press"

 

Here is the model I have:

 

12 Ton Shop Press

Awesome, thats exactly what I wanted to know, though amazon does have them for cheaper... except... shipping... Arg.... Shipping or gas... *ponders*

[h&k machineguns]

Okeedokee, this isn't the first time I've seen a Harbor Freight press mentioned. Now, I get a Harbor Freight catalog every two weeks, and I've checked it and their website for this several times... still can't find it. Do they call it something else or am I just completely blind?

They are commonly called a "shop press"

 

Here is the model I have:

 

12 Ton Shop Press

Awesome, thats exactly what I wanted to know, though amazon does have them for cheaper... except... shipping... Arg.... Shipping or gas... *ponders*

You may want to check with your local HF. I bought mine for $89.00 from them. Also HF usually has a coupon for any single item purchase,you can download it from their site and print it out. I used the coupon. Before the press was around $100.00. This was about 8 months ago.

[FrankRizzo]

Drilling and taping your existing bottle jack to add a pressure gauge is probably the best way to get repeatable results with your pressing operation. You might also replace the existing bottle jack with one that was manufactured with a port for attaching the gauge such as the Norco "G" models (12-Ton 76412G).

 

Another alternative is to buy a calibrated assembly like Wolter's P2F gauge, which sits under your spindle base and measures the applied force via a gauge on the unit:

 

http://www.wolterpyrotools.com/pyrotools/pyrotool_0750.jpg

 

Or, make your own for a third of the price by attaching your own fluid-filled gauge to one of these and doing the math yourself because of the odd-sized cylinder:

 

http://www.harborfreight.com/cpi/photos/42800-42899/42830.gif

 

http://www.harborfreight.com/cpi/ctaf/Disp...temnumber=42830

[cplmac]

If you're ram is getting cocked inside the tube it sounds like you might be using a ram that is to small for the tube. I have used an arbor press for small rockets (<1lb.). If you plan on making rockets bigger than your 1 pounders I would recommend using the press. And it is a good idea to press as perfectly vertical as possible. It presses your comp more evenly, and helps prevent damage to your tooling and motor.

So your saying an Arbor press is good for making rockets bigger than 1 lb ? I think that's what I got from your post. Thanks

 

Is the Arbor press much faster than the hydrolic bottle types ?

I was saying an arbor would be okay for the smaller stuff. I got my press from Maxtool.com. It is a Troy ME8820 20 ton air over hydraulic press. It cost 279 plus 130 for shipping.