DieselTech Report post Posted December 14, 2023 Guys & gals in feburary or march I'll be getting a new cobra class 4 sewing machine. My question is will it sew thru kydex plastic used in holsters & knife sheaths? Will it sew thru a plastic bicycle seat pan? Some type of flexible plastic. No sure what yet thou. Thanks any & all help will be greatly appreciated. Quote Share this post Link to post Share on other sites
PeterinID Report post Posted December 14, 2023 I don't think it will sew through either, not uniformly or reliably. I think you would snap needles and crack plastic. If you drilled holes that matched stitch length you might possibly get ok results. Quote Share this post Link to post Share on other sites
AlZilla Report post Posted December 14, 2023 There's a youtube video of Alexander Dyer using a Cobra class 26 and sewing canvas to plywood. I think it'll sew kydex. Quote Share this post Link to post Share on other sites
DieselTech Report post Posted December 14, 2023 48 minutes ago, PeterinID said: I don't think it will sew through either, not uniformly or reliably. I think you would snap needles and crack plastic. If you drilled holes that matched stitch length you might possibly get ok results. Yeah I was curious because Cobra said it will sew thru plastics with the correct needle selection. I was just trying to get a idea on how thick of plastic & what types of plastic. Thanks. I appreciate it. Quote Share this post Link to post Share on other sites
DieselTech Report post Posted December 14, 2023 40 minutes ago, AlZilla said: There's a youtube video of Alexander Dyer using a Cobra class 26 and sewing canvas to plywood. I think it'll sew kydex. I'll have to see if I can find that video, I would like to see how the cobra class 26 does. I would think if the Class26 can do that, then a class 4 will surely punch thru kydex, with the correct needle selection. I appreciate your time & knowledge. Thanks. Quote Share this post Link to post Share on other sites
AlZilla Report post Posted December 14, 2023 45 minutes ago, DieselTech said: I'll have to see if I can find that video, I would like to see how the cobra class 26 does. I would think if the Class26 can do that, then a class 4 will surely punch thru kydex, with the correct needle selection. I appreciate your time & knowledge. Thanks. Quote Share this post Link to post Share on other sites
DieselTech Report post Posted December 14, 2023 1 hour ago, AlZilla said: Thanks appreciate that. Much appreciated. Quote Share this post Link to post Share on other sites
DieselTech Report post Posted December 14, 2023 They should use that as a promotion video. That's pretty amazing. Quote Share this post Link to post Share on other sites
nylonRigging Report post Posted December 15, 2023 (edited) On 12/13/2023 at 4:49 PM, DieselTech said: Guys & gals in feburary or march I'll be getting a new cobra class 4 sewing machine. My question is will it sew thru kydex plastic used in holsters & knife sheaths? Will it sew thru a plastic bicycle seat pan? Some type of flexible plastic. No sure what yet thou. Thanks any & all help will be greatly appreciated. I do some internal stiffing plates in panels with some of sew designs i sell using thicker than what is used in Holster construction. Holster kydex/ABS is pretty thin stuff . You going to sew threw it like butter even with using a lot smaller sew machines than the bigger class4 . The ABS plastics are more rigid and harder material as you go thicker. You will still punch threw no problem . Your Polyethylene plastic sheets are easy 'smoother' on the needle and nicer to so threw. I think the Polyethylene less abrasive on the thread than the harder ABS, and easy to tension look good. All depends on what you making/sewing and type, thickness..etc. but Always keep in mind that the weakest point for bend fatigue crack/breakage, will always be the sew line threw in the plastic, the line of 'holes you punch' . . edit add: .. I seen old singer class7 sew threw silver dollars... LOL . Edited December 15, 2023 by nylonRigging Quote Share this post Link to post Share on other sites
AlZilla Report post Posted December 15, 2023 12 hours ago, nylonRigging said: I seen old singer class7 sew threw silver dollars... I sometimes tell people I could sew a fender on my car with the 441 clone. Maybe I'm not exaggerating! Quote Share this post Link to post Share on other sites
Wizcrafts Report post Posted December 16, 2023 21 hours ago, nylonRigging said: I seen old singer class7 sew threw silver dollars Watch this video clip: Quote Share this post Link to post Share on other sites
kgg Report post Posted December 16, 2023 6 hours ago, Wizcrafts said: Watch this video clip: That was interesting as to what an old Landis 16 can do. Pure punching power. kgg Quote Share this post Link to post Share on other sites
DieselTech Report post Posted December 16, 2023 8 hours ago, Wizcrafts said: Watch this video clip: That was unreal !!! What machine was that they were using to sew thru a coin. Plum Nuts!!! Quote Share this post Link to post Share on other sites
Wizcrafts Report post Posted December 16, 2023 1 hour ago, DieselTech said: That was unreal !!! What machine was that they were using to sew thru a coin. Plum Nuts!!! This was first done by Campbell Randall, the rebuilder and primary dealer for Campbell and Union Lockstitch machines. Check out their video where they sew a penny onto a stack of leather. There is a full description of the machine and its setup. Quote Share this post Link to post Share on other sites
DieselTech Report post Posted December 16, 2023 6 hours ago, Wizcrafts said: This was first done by Campbell Randall, the rebuilder and primary dealer for Campbell and Union Lockstitch machines. Check out their video where they sew a penny onto a stack of leather. There is a full description of the machine and its setup. May I ask what that machine was originally built for? & what era was that machine. That's soo cool seeing that machine in action. Thanks. Quote Share this post Link to post Share on other sites
Wizcrafts Report post Posted December 18, 2023 On 12/16/2023 at 4:28 PM, DieselTech said: May I ask what that machine was originally built for? & what era was that machine. That's soo cool seeing that machine in action. Thanks. Both the Randall and Union Lockstitch machines were designed to sew harnesses and saddlery. They originally used Z twist linen thread run through liquid beeswax. Other uses for these machines included holsters for law enforcement, tug straps for sulkies, weightlifters belts, footballs (Union Lock), briefcases and some saddlebags. Both use a separate barbed needle and an awl to punch holes. The Randal machines use the awl to move the leather, while the Union Locks are needle driven. The Randalls like to chug along at about 300 stitches per minute, maximum while the Unions are designed to fly at 800 spm. They are a higher speed production machine for long straps, whereas the Randall is for more precision sewing. If you ever get to meet someone selling a Union Lockstitch in person, have the owner run it flat out for you. Bring earplugs and hold onto your junk! Quote Share this post Link to post Share on other sites
DieselTech Report post Posted December 18, 2023 5 hours ago, Wizcrafts said: Both the Randall and Union Lockstitch machines were designed to sew harnesses and saddlery. They originally used Z twist linen thread run through liquid beeswax. Other uses for these machines included holsters for law enforcement, tug straps for sulkies, weightlifters belts, footballs (Union Lock), briefcases and some saddlebags. Both use a separate barbed needle and an awl to punch holes. The Randal machines use the awl to move the leather, while the Union Locks are needle driven. The Randalls like to chug along at about 300 stitches per minute, maximum while the Unions are designed to fly at 800 spm. They are a higher speed production machine for long straps, whereas the Randall is for more precision sewing. If you ever get to meet someone selling a Union Lockstitch in person, have the owner run it flat out for you. Bring earplugs and hold onto your junk! Thanks Wizcrafts. I appreciate the history lesson. I like to hear about machines & older things long & forgotten about. Quote Share this post Link to post Share on other sites
Wizcrafts Report post Posted December 18, 2023 4 hours ago, DieselTech said: Thanks Wizcrafts. I appreciate the history lesson. I like to hear about machines & older things long & forgotten about. Sometimes, History continues into the present day. The Amish in the Thumb area of Michigan still use Landis and Randall needle and awl harness stitchers to make and repair harness for their horse drawn carts. They are either foot pedaled, with twin bicycle style pedals, or line shaft driven by whatever power source they deem acceptable. I was offered a rebuilt and working Randall, for $2200, by an Amish who used to visit my shop until 2022. I should have taken him up on it when I had the money in the bank. These machines lay down a stitch that closely resembles hand sewing on both sides. Note: parts and accessories for needle and awl machines are often hard to get and usually very expensive. Quote Share this post Link to post Share on other sites