pyrodoc Posted March 15, 2014 Share Posted March 15, 2014 Hi, http://www.brianredmond.net/dwilliams/press/press.html Will be making one via the above link. Looks kinda easy to make with easily available materials. For me hydraulic press is essential because more or less most of the compositions contain metal so ramming is out. How strong is the plexiglass blast screen? Doc Link to comment Share on other sites More sharing options...
marks265 Posted March 15, 2014 Share Posted March 15, 2014 Doc, Original equipment manufacturers usually use polycarbonate material for machine guarding. I also don't bolt my polycarbonate tightly to allow for flexing. If it it is too tight the polycarbonate could crack at the bolt holes. Also Lexan is a company that makes polycarbonate sheeting. Some people believe that Lexan is a material and not a company. When looking at the link you could also put a tubing over the threaded rod which would also help to reduce wear. I also saw a comment where someone mentioned welding the plate directly to the head of the jack. This is a bad idea because it will always flex at that juncture and eventually break anyway unless it is substantially well guided. Mark Link to comment Share on other sites More sharing options...
Col Posted March 15, 2014 Share Posted March 15, 2014 Its better to use 4 threaded rods as 2 can be susceptible to twist. If you use M20 threaded rod you can slide 25mm x 2.5mm wall steel (cds) tubing over it and use 25mm linear guides on the press plate. I use 2 vw golf tailgate rams to push the press plate down as i couldnt find springs with enough travel.As Mark suggested its best to have the blast shield floating, mine is attached to the press plate and travels between 2 steel bars at the top of the press. The benefit of doing it that way is the shield will automatically change length according to the ram extension which optimises the shields strength. Link to comment Share on other sites More sharing options...
ddewees Posted March 15, 2014 Share Posted March 15, 2014 Slightly off topic, but has anyone ever had the blast shield do anything to actually save them from harm? Don't get me wrong, I have double ply Lexan completely shielding me from my entire press. But the few stories I've heard of regarding fuel ignition were from removing the tooling using a twisting motion. Just curious... Link to comment Share on other sites More sharing options...
nater Posted March 16, 2014 Share Posted March 16, 2014 (edited) I have not heard of anyone who has had a motor pop while pressing. The few stories of accidents while pressing motors that I have heard of were while a rammer was being removed by twisting. Likely, the same cases mentioned above. It is possible that misaligned tooling could kick back at you while under pressure, which the shield will help protect. I have heard talk of people sacrificing a shield and set of tooling to test them, but I don't think they followed through with it. I can sometimes get scraps of polycarbonate, but I don't want to sacrifice the rest of the tools to do this myself. MAYBE when I upgrade my press I would put a call out for an old tooling set and sacrifice my press frame and shield, maybe. I have seen a lexan blast shield protect a group when a large multibreak with a heavy bottom shot blew in a steel mortar. The shield was 3/4" lexan sandwhiched between two sheets of 3/4" plywood. The plywood was destroyed on both sides and the lexan was warped. Everyone nearby walked away shaken, but not hurt at all. I liken a shield to my bicycle helmet. I once crashed hard, broke the helmet in half and still had a concussion. The head injury would have likely been worse without it. I don't trust a shield completely to protect me while pressing rockets, but I think it will help protect some. I work carefully to make my chances of finding out for sure as slim as possible. Cleaning out the rammers between increments and carefully marking and observing the no-pass lines are a must. Edited March 16, 2014 by nater 1 Link to comment Share on other sites More sharing options...
pyrodoc Posted March 16, 2014 Author Share Posted March 16, 2014 Thanks all, you guys always give some cool tips. Though, i will start with flares and torch just collecting materials slowly. One more question which comes to mind is "For torch/flares is our body pressure enough to press?" . Can anyone point me out to a video of flare/torch making? Doc Link to comment Share on other sites More sharing options...
Arthur Posted March 16, 2014 Share Posted March 16, 2014 Manually applied force depends on how big you are! More importantly the pressure applied to the comp is force/tool area small tubes press by hand large tubes need power. Link to comment Share on other sites More sharing options...
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