sbrownn

Thanks, that's good to know.

The critical part is actually where the top meet the outer frame; it needs to be thick enough to keep the sides from splaying out when pressed. I design my molds to shape dry bridle leather because I don't want the color change that results from getting it wet. Thicker leather takes a stronger mold...obviously. So that means an automatic change to a higher resolution print on the top layer or more heat? What is the software actually telling the machine to do?

It's the CAD that takes some time to get competent at. The 3D printing part just goes to work on the CAD files. If you have a local university, sign up for a CAD class and you will learn more than you ever need to know and have fun doing it.

That can be easily solved by using a two part mold that, when the sides bottom out, has a little extra clearance between the top of the male mold and the bottom of the female mold; no marks. It's my most used leather working tool.

Very nice. I had a fly press I used in my CAD class and I wish I still had it.

Leveling is overrated. The machine will easily compensate for things not being perfect. I level the bed of my Flashforge at three points in less than two minutes and it works fine.

I have a servo and speed reducer on my Campbell-Randall but it's not quite enough torque for thick stuff at the speed I want to run (slow). I'm thinking of adding a second speed reducer. I have no experience with the ULS but I would love to have one.

I've never seen one either and I don't care about sewing fast which was, I think, their claim to fame. If I could find one to buy I would though.

Go Campbell Bosworth Cyclone.

I understand. Anyone looking for a different way to produce a quality of stitch that gets closer to hand stitching with less hand work certainly doesn't care as much about the number of stitches per minute and probably is more concerned with the backside appearance than 95% of our customers. Most of my stitching, except for long straight runs, is done without using the motor at all. My machine is over 100 years old and the stitch length control linkage has worn over the years to the point I don't trust it to be as accurate as pricked holes. Before I make each individual stitch I make sure the awl is perfectly lined up with my pricked pattern. It is time consuming to be sure but I find that I enjoy running the Campbell-Randall monster by hand and compared to hand stitching, well there really is no comparison on a time basis. As I was pointing out, I have now progressed from just marking the hole locations with a pricking iron to actually punching them before I sew. It adds another level of complexity to the process but I can see a difference that I feel makes it worthwhile for me to do on some items. Do my customers notice? Absolutely because I make sure I point it out to them.

I would agree but with one caveat: "reasonably" covers a lot of ground. The "good guys" at hand stitching can make a stitch no machine can match but they are few and far between and unless they have some sort of reputation and high end clientele they can't make any money at it. I'm looking for the middle ground; a machine stitch that is better than just pushing the pedal but a lot faster than sewing by hand.

You can 3D print anything you can think of and I've printed both presser feet and throat plates. Granted, they don't last as long as steel but it's surprising how long they do last. The throat plate would probably be perfectly doable with a walking foot only machine; with a needle or awl feed machine probably not so much. Are there any walking foot only feed machines?

Thank you so much for the advice. All good tips, especially the dampening. I'm sure I read that before somewhere but thanks for reminding me.

I have to admit that my quest is less of a practical nature than an experiment. Since I only have the one machine I find myself having to use the wrong machine when I'm sewing thinner stuff. I have seen pictures of your machines and I would love to have one but so far I haven't found one to buy. I think having just a hole for the needle instead of a slot would help a lot. I even considered making myself a needle plate that would have a hole that moved with the awl and then spring back to its initial position once the needle let it go. I have some presser feet with bumps on them for the top but that's not where I need it and they don't work to go around corners. Almost all of my work is with bridle leather and the stuff I'm making doesn't hide the backside stitch. A good example is a journal cover. For a journal cover you need both the front and back side stitches to look good because the user sees them all the time.

I think that is a good suggestion to try.

Here are two images of the front and back side sewing. For this experiment I glued two pieces of 6 oz bridle leather back to back and sewed them at a stitch length of 5mm. If I had used a recommend size awl one half size larger than the needle and not pre pricked the holes the backside tearout would be obvious (don't ask how I know). On the backside of this example the appearance of the stitch holes is obviously different but there is no apparent tear out.

The problem is that on most heavy leather machines the feed is assisted by either the needle or, if a needle and awl machine, the awl. This requires a slotted plate, not a plate with just a hole. I couldn't tell about the 105-6 but it looks like a wonderful machine and if anyone wants to sell one I'm in the market.

It's probably not any faster to use the machine and I have found the pricking iron to be more exact than my machine as far as stitch spacing. I think that once you "blow out" the backside it is difficult to fix. The pricking irons, because they are bottoming on some sort of pricking pad, do not blow out the backside and neither does the awl that is smaller than both the needle and the pricking iron tooth. Work in progress but the results are promising. Did I mention that I like running the machine but dislike hand stitching? Thank you Tom.

I have tried some 3D printed throat plates tailored to both awl width and stitch length but they didn't seem to make much difference on tear out. Right now I am using a 0-1/2 awl and a 1 needle on pre pricked holes and it looks pretty good. Not as good as expert hand stitching but better than my hand stitching. My needle and awl are not perfectly positioned because I can't seem to move the head enough to accomplish it. They are close though and the pre pricked holes minimize the problem. I will post a couple of pictures. Thanks, as always, for your expert comment.

Not selling them as handsewn. That would be dishonest. Selling based on quality. IMHO most machine stitching doesn't look okay on the backside.

I have been trying to come up with a process that would allow me to machine stitch with a result that comes closer to duplicating the appearance of hand stitching. One of the issues with a machine stitching is the appearance of the backside stitch; it is difficult to repair the damage that the needle does to the backside in the process of going through. Once the stitch has been made, the backside appearance can be improved with the use of an overstitch wheel or by hammering down but these are time consuming too. First of all, if you are trying to make a nice machine made backside stitch, start with some sort of needle and awl machine. Not necessarily because they do a better job, because if improperly set up they don't, but because you have more variables to tweak. On a Campbell-Randall, which is what I am using, you can mess with the needle and awl sizes, the top and bottom thread tensions and the knot position. Almost all needle and awl sewing calls for a awl that is sized larger than the needle and the problem with this is that the needle is too small to repair the damage caused by the awl. What I really want is a needle that is big enough to turn back in the "blow out" that results from the awl punching through the backside and still make a hole big enough for the knot. First and foremost, make sure that both the needle and awl are sharp. I hone my awl just like a knife blade so when it pushes through it cuts instead of breaks the leather fibers. My current process consists of a needle that is one size larger than the awl and pre punching the stitch holes with a pricking iron. When you use a pricking iron you are usually punching down on a pad and the presence of the pad helps to minimize tear out from the pricking iron. I use an awl that is a little smaller that the pricking iron but angled to match it and a needle that is bigger. The pricking iron has already created a hole large enough for the knot and the needle is large enough to fold back the edges of the hole the pricking iron has made. If the machine weren't awl feed, I could probably get rid of the awl completely but by undersizing the awl I can minimize the damage it does to the backside. I realize that this process is not as efficient as machine stitching and I wouldn't use it on something like the stitching on the edge of a belt but I would use it stitching the edge of a wallet or any other place where I wanted to show off the stitching but didn't want to spend the time doing it by hand. Can you please move this post to a more appropriate forum?

Thanks for posting the picture. The backside looks pretty good. What would you do further if you needed the backside to look as good as the frontside? I have tried a number of things but have yet to come up with a protocol that works as good as I would like.

Can you post a picture of what the backside stitch looks like? I am thinking of buying a 441 clone but am concerned about what the backside looks like. Seems like results are all over the place depending on the leather type and the set up. Right now I'm using a Campbell-Randall to stitch in pre-pricked holes and it looks okay but I need a machine with a long cylinder arm for a project I'm doing.

I have had a Tippmann and the Outlaw looks pretty similar. The Cowboy 3500 head only machine can be purchased with a manual operation setup for not much more than either the Tippman nor the Outlaw. For a little more you can get it with the table, servo and accessories. IMHO the triple feed walking foot Cowboy far out classes the Tippmann and the Outlaw.

I have found that PLA is strong enough for most leather work applications and is much easier to print consistently than ABS. I have done lots of both over the last 10 years and now print almost exclusively in PLA.