# Screen lifting in the front when clamped



## camscam (Apr 1, 2007)

I dont really know the best place to post this question and I feel like I should have been able to figure this out on my own but I've got a manual 4-color press I'm starting with and the arms and screen clamps seem pretty standard but this is really confusing me and is causing problems with the prints I'm making.

the picture pretty much says it, when I screw the screen into the clamp the tighter it is in the clamp the more the front of the screen lifts up. If I hold it down in the front and then screw the 2 knobs down when I let go the screen is loose and will come out when I lift the arm to change colors.

This causes a problem because the distance the screen is from the platen increases and the ink lays down all crappy and uneven. If I want to do off contact printing the screen is so far from the surface in the front that I can't set it up right. Like, if the top of the screen is "just off" the platen then the front will be like an inch up.

Maybe I'm confused or something but its not like I'm loading the screen crooked or anything. It only lifts when the bolts get tightened but thats how the screens are kept in place! Any advice or a way to get around this will help. If my description is confusing or you need more info for a suggestion please ask me a question. Sorry about the crappy diagram but its a side-view of the press, in profile and shows how the screen looks when its brought down to the platen.


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## neato (Mar 21, 2006)

What kind of press do you have?

You should have an adjustment to correct this.


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## Fluid (Jun 20, 2005)

make sure your frame is all the way in the clamp. From your diagram there is a huge gap between the frame and back of the clamp. This could be part of the issue. Also check to see if the press has a adjustment for tilting as well as normal up and down off contact.

This is one reason I do not like rear clamp press. Side claps seem to be the best option out there for a manual press


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## camscam (Apr 1, 2007)

> What kind of press do you have?


Teeshirtprinters.com - Four Color Screen Printing Presses, screenprinting presses, silkscreen presses



> From your diagram there is a huge gap between the frame and back of the clamp.


Yea thats cause its a crapy diagram to show how the angle ends up in case I didn't explain it right. In "real life" I have it all the way to the back of the clamp. There is a bolt about a few inches from the top of the platen that can be adjusted to set how close to the platen the arm will go but I haven't seen anything on it that can adjust the tilt of the clamp or anything....

So I'm not crazy after all?? Usually there is a way to fix this?? Is there a technical name for this as well?


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## Squirts (Feb 17, 2006)

camscam said:


> Teeshirtprinters.com - Four Color Screen Printing Presses, screenprinting presses, silkscreen presses
> 
> Yea thats cause its a crapy diagram to show how the angle ends up in case I didn't explain it right. In "real life" I have it all the way to the back of the clamp. There is a bolt about a few inches from the top of the platen that can be adjusted to set how close to the platen the arm will go but I haven't seen anything on it that can adjust the tilt of the clamp or anything....
> 
> So I'm not crazy after all?? Usually there is a way to fix this?? Is there a technical name for this as well?


 I enlarged the pics of your press and think I might know whats causing it to tilt up... the screen clamps look like they were bent from flat stock to form the "U" that makes the clamp... If this is so then there will be a slight curve in the clamp... Not a perfect 90degree bend as in your drawing...
when you tighten the clamps the screen is probably sliding out the curve.. try "Not" putting your screen all-the-way back in the clamp leave it just far enough forward to clear the curve so the screen can clamp down straight.... Good Luck Chuck


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## camscam (Apr 1, 2007)

> so then there will be a slight curve in the clamp... Not a perfect 90degree bend as in your drawing...


you're right about the curve in the clamp but taking this picture I mean does this look bent to you guys or is it just me? there are 4 of these arms and they are all tweaked differently upon closer examination. Was I "had" by the manufacture or would this be considered worthy of return? Is there a "fix" for this? I'm I freaking out for no reason an all presses are like this? Should I start beating it with a hammer untill everything is straight?


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## NeoLogical (Jul 19, 2007)

Hey,

I might have an idea that may help, at least a bit, I run into this error alot, and it seems in my case to be the crappy wooden screens that I got that are'nt straight anymore. What I do to help offset the bolts pushing down the back edge of the screens is to put a small piece of thick (or thin, doubled up) cardboard under the screen towards the back. This helps to lift the back edge up and the front edge down.

oh and thats another thing, your screens cant go to the very back of the "C" clamp because the bent metel will slowly push the screen forward (just a bit).

Play with a bit and let us know if it helps.

Hopefully you diddnt get ripped off w/ a crappy machine. The same thing happened to me, and I wish I could return my machine. If it has registration problems and tons of other probs..... send it back while you can!

good luck!


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## Fluid (Jun 20, 2005)

Tough to say whats happening. Check your wooden frames on a true flat surface and make sure they are not warped.

Can you post a picture with more of the nuts and bolts, registration fork, etc. 
Your press should have a manual? Does it mention all the adjustments you can make?

Might just be the press and how it is made.


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## camscam (Apr 1, 2007)

> Your press should have a manual? Does it mention all the adjustments you can make?


That was the FIRST thing I contacted them about when I got this. Not papers, no instructions, nothing came with it. I've been calling and emailing the guy every day for over a week with limited email responses that tell me to call him :S
I can take more pictures. No problem if it will help but this picture from the company's website shows everything pretty well.
http://www.teeshirtprinters.com/presses/41table.jpg

And how do you keep a screen frame from warping? Or is there a way to fix one that is warped? I guess mine is a little "warped" because on the opposite corners, one pair sits flush and the other 2 are a slight amount up but it seems like its very little.

Does that mount look like its got a tilt in it to anyone else though? I think thats more of a problem then anything, if there is an adjustment I have no idea. Is there anything on it I can look for?


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## Fluid (Jun 20, 2005)

tough call. I bet its the press but hard to say for sure. I doubt the slight warp of your frame is causing this much of an issue.

Might post one more pic with a screen locked in and in the print position over the palette. Will give us a little better visual.


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## RichardGreaves (Nov 7, 2006)

Perhaps the head springs are stronger than the clamping force of the thumbscrews. If there is resistance when you lift, it could twist the frame at its weak point, the clamp. A bent steel 'yoke' is very common.









This what you want the off-contact to look like. When I print on a manual press, I tape something solid (not compressible) to the bottom of the frame so it touches the 'neck' of the platen making a bridge of the mesh. When I print, the downward squeegee force can't change the off-contact distance as I stroke.

Try a thin flat plate of metal that spreads the force of the clamps over the frame bar in the clamps.








Notice how this Hopkins head can tilt to keep the screen parallel to the platen if you want to raise off-contact.

Your flash picture certainly shows that the clamp assembly tilts up when the head is down. 









Imagine the print head is your arm. The elbow is the back hinge and your wrist is the clamp. Some presses have clamp assemblies that can be tilted so the screen is parallel to the platen. Alas, yours doesn't.


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## Tmacker (May 18, 2007)

Try a thin flat plate of metal that spreads the force of the clamps over the frame bar in the clamps.

That's a good fix with the metal plates. We ran into this problem often. Wooden frames do warp, check the frame for skew on a nice flat surface. Try another frame in the same clamp and see if the result is the same. We used to coat our wooden frames with a heavy duty Urethane or Marine varnish (used on boats) kept the moisture out from reclaiming, and they lasted longer as a result. If you clamp your screen too tight, you'll end up stripping the threads on the thumb screws. We often added additional clamps (C-Clamps) to assist on the hold. Some old manuals we used to weld C-clamps on the frame holders, holding registration on a multicolor is key though, so we scored the 'foot' of the clamp to give it a better grip. Eventually we did go to a side clamp press, and aluminum frames.


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## camscam (Apr 1, 2007)

You guys are awesome, richard's info on doing off contact here is going to really help when I can straighten out the screen "front to back". I will source a metal plate at the hardware store and maybe JBweld a pair of nuts to the plate, spaced for the clamp screws to go into but not right now. I will try everything you guys said eventually;

but I just now got a call back from the manufacturer and they say that they have been having phone and email trouble this week and I will give them the benefit of the doubt. He apologized and said "they stand behind the product and wants to make it right" so that's good, but the press is still made the way that it is and I believe that it because of the design it could be subject to what richard said about spring pressure. 

According to the manuf. when they make it, the arms are welded in a jig thats sets the angle, which is not a "defect". I did see that all 4 arms had the same angled plate. He thinks the c-shaped "channel" that the screen screws into may be bolted too low on the welded plate. The holes that bolt the clamp assembly to the angled plate at the end of the arm are sloted so I'm going to adjust that tonight and see what happens. I will post updated picture.


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## Fluid (Jun 20, 2005)

Good Deal. Thanks for the feedback and let us know how it works after your tweaking this weekend.


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## RichardGreaves (Nov 7, 2006)

camscam said:


> I will source a metal plate at the hardware store and maybe JBweld a pair of nuts to the plate, spaced for the clamp screws to go into but not right now.
> 
> , ..... but the press is still made the way that it is and I believe that it because of the design it could be subject to what richard said about spring pressure.
> 
> ...












If the screens always point UP instead of parallel, you may have to lower the platens.

Get a nice flat piece of plywood or actually use another platen to help adjust the off-contact distance.
Put some form of a spacer on your platen. Quarters or washers. Distance depends on your mesh tension.
Loosen the slotted bolts on the clamp.
Pull the head down.
Put our extra platen in the clamp and tighten the thumbscrews.
Use clamps to hold the platens together with the spacers keeping the plates from touching like meat in a sandwich. This is your basic off-contact distance. You can put wooden stir sticks under other screens if you need more off-contact.
Tighten up the slotted bolts.
Loosen the C-clamps holding the platens together and test out your off-contact.









Here's a scheme you could use with side clamps.


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## camscam (Apr 1, 2007)

Its different in the picture on the manufacture. website. The c-shaped channel the screen screws into is mounted onto that angled plate with 2 bolts but its a slotted mount and the channel is adjustable up and down. Well for whatever reason I don't totally grasp, because I failed Trigonometry, but by moving that channel/clamp piece up, the front of the screen stopped sticking up at an angle and went down.

So now its pretty even accept for the warp in the screen which I still would like to know if anyone has tips for avoiding a warped screen issue. Richards explanation about adjusting the platen is actualy going to help me with the warped screen I have, but I would like to avoid the warping in the first place if possible.

So do they sell nicer clamps that I could upgrade to, like a side clamping head, that would replace the one I have or would that mean getting a different press with more features overall?


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## Fluid (Jun 20, 2005)

get aluminum frames if you stay with static frames. They will not warp unless you bend the aluminum


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## RichardGreaves (Nov 7, 2006)

Fluid said:


> get aluminum frames if you stay with static frames. They will not warp unless you bend the aluminum


To Richard's (Fluid) post I would add:

The picture you posted in link #6 shows a wooden frame with single cut, 45 degree mitered corners AND NOT coated with a sealer like polyurethane. Inferior design. I'm sure it costs less to make and sell.

The picture I posted in link #11 shows a frame with half-lapped corners and although NOT sealed, should not warp. 

A sealed wooden frame with some class of fitted corners will be just as strong and resist warping as aluminum frames.

The reason every manual printer should buy aluminum frames is because they are about 1 pound lighter than wooden frames and you don't have to spin and stop that extra weight, especially as you print a 6 color job.

This is the same logic that race car builders use when they put 'mag' wheels on their cars to reduce unsprung weight.








If I had an automatic press and I wanted to save money using static frames, I would buy wood. 

If I had a manual press and wanted to save money buying static frames I would buy aluminum.

If I print light colored ink on dark fabric, the most important function is TENSION and I would use Newman Roller Frames at 25+ newtons.


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