pointystuff Report post Posted February 23, 2011 My goal is to make a seamless helmet dome from a single piece of 3 mm vegetable-tanned leather. I've experimented with wet leather and a wood hat dome form. With the wet leather draped over the dome, the edge of the leather secured via metal toggles to some eye hooks mounted around a thick board beneath the dome, and the dome perched on top of a hydraulic bottle jack, I've been able to pull a very shallow dome. However, the bottom half of the dome shape there were a lot of folds of excess leather. It may require a very tall hydraulic ram jack to get the folds of excess material to stretch out. Any suggestions? Quote Share this post Link to post Share on other sites
dirtclod Report post Posted February 23, 2011 I've never made one but i think i would cut the leather in a circle if you didn't. The wrinkles i would try rubbing them out or as much as i could. You may still have to put a seam or two in. Quote Share this post Link to post Share on other sites
MartyS Report post Posted February 24, 2011 you are going to get less stretch where the leather is touching the form, so using a combination of intermediate forms and grease will help. A female form, or combo M/F might be necessary. Maybe a combo different shaped male pushers into a female form. Cut up every disaster and measure the wall thicknesses, with an eye on getting them overall even. Look up membrane pressing. Or just switch to rawhide. cheers M Quote Share this post Link to post Share on other sites
pointystuff Report post Posted February 24, 2011 you are going to get less stretch where the leather is touching the form, so using a combination of intermediate forms and grease will help. A female form, or combo M/F might be necessary. Maybe a combo different shaped male pushers into a female form. Cut up every disaster and measure the wall thicknesses, with an eye on getting them overall even. Look up membrane pressing. Or just switch to rawhide. cheers M I do vacuum forming with abs plastic sheets; I also make urethane and silicone molds. Perhaps those two hobbies can help solve this problem. Maybe a mold (positive and negative) made of cement/concrete would do the trick...along with a hydraulic press of 2 tons or so. Quote Share this post Link to post Share on other sites
TomBanwell Report post Posted February 24, 2011 From my experience you won't be able to stretch/compress the leather that much without wrinkles. Quote Share this post Link to post Share on other sites
