Homebrew PCBs

An easier way is to warm up the copper first with a hair dryer, before 
putting  the the paper with the toner on it , and then use the iron.


Regards

Tony VK2IC

lcdpublishing wrote:

>I agree completely about the two primary points - 
>
>1) Rubber or some other material that gives to compensate for board 
>thickness variations
>
>2) un-even heat from the element - this would be the biggest problem 
>to correct I believe.  The only thing that comes to mind is to have 
>a thick metal plate on the heating element side of the press.  Then, 
>to use it, turn it on and let it get good and hot prior to use.  
>Even then, I still think there is going to be some problems with 
>some areas being hotter than others.  
>
>My brother in-law is a garage sale junkie.  I will describe to him 
>what I am looking for and he will find one for a couple of bucks 
>somewhere - that's worth a try :-) 
>
>Chris
>
>
>
>
>
>--- In Homebrew_PCBs@yahoogroups.com, "Stefan Trethan" 
><stefan_trethan@g...> wrote:
>  
>
>>On Thu, 20 Oct 2005 21:58:52 +0200, lcdpublishing  
>><lcdpublishing@y...> wrote:
>>
>>    
>>
>>>Hmm, this is a good point so it bears checking on.  I currently 
>>>      
>>>
>use
>  
>
>>>a clothes iron and press it by hand and use about 5 inches 
>>>      
>>>
>square of
>  
>
>>>the sole plate at any one time.  I weigh about 225 pounds these 
>>>      
>>>
>days
>  
>
>>>and am pushing down on the iron with a fair amount of force - 
>>>      
>>>
>lets
>  
>
>>>say half my weight 112 pounds - which I am sure is more than I am
>>>pushing down.
>>>5 x 5 = 25 sqaure inches of surface area
>>>112 / 25 = 4.48 pounds per square inch
>>>This has worked very good for me so far (although I suspect I 
>>>      
>>>
>have
>  
>
>>>beginners luck).  So, a 12" x 12" board would require
>>>12 x 12 = 144 square inches x 4.48 pounds per square inch = 645
>>>pounds of presure on that plate for a large circuit board.  This
>>>would be pretty hard to achieve without some form of mechanical
>>>advantage (unless I keep putting on weight since I quit smoking!)
>>>Chris
>>>      
>>>
>>My worry was not so much about the magnitude of pressure in 
>>    
>>
>general, but  
>  
>
>>how to adjust if from board size to board size.
>>With the fuser i can choose to let the wide or the narrow side 
>>    
>>
>run  
>  
>
>>through, thus i can keep the "length" in the fuser similar with 
>>    
>>
>all the  
>  
>
>>different boards i make. I have not found variations of a factor 2 
>>    
>>
>or even  
>  
>
>>3 a problem. The rubber roller is doing a pretty good job at 
>>    
>>
>keeping  
>  
>
>>things in contact.
>>
>>
>>If a press should work, i think it must have a rubber plate below 
>>    
>>
>the  
>  
>
>>board, a rigid material both sides will probably cause trouble. 
>>    
>>
>Also, i  
>  
>
>>would be afraid of temperature patterns, they can be quite extreme 
>>    
>>
>with  
>  
>
>>heating elements that are concentrated in one area. A pressure 
>>    
>>
>gauge could  
>  
>
>>be made easily, just take the bathroom scale and put it between 
>>    
>>
>the press  
>  
>
>>plate and the screw/lever you use to tighten it.
>>
>>At this point, i'm just not seeing the advantages.
>>But you know - never listen to the nay sayers. Look at the 
>>    
>>
>arguments why  
>  
>
>>it mightn't work, fix them, and do it.
>>
>>ST
>>
>>    
>>
>
>
>
>
>
>
>
>Be sure to visit the group home and check for new Links, Files, and Photos:
>http://groups.yahoo.com/group/Homebrew_PCBs
>
>If Files or Photos are running short of space, post them here:
>http://groups.yahoo.com/group/Homebrew_PCBs_Archives/ 
>Yahoo! Groups Links
>
>
>
> 
>
>
>
>
>  
>


[Non-text portions of this message have been removed]