First slip joint WIP

J S Machine

Well-Known Member
*Finished knife pics on page 7*

I wasn't gonna do this, but I figured you guys might like to see my trials and tribulations as I attempt my first slippie. Mods, I hope I'm not out of line posting this here.

I drew this thing out on paper a couple dozen hundred times or so, and finally got a pattern I could work with. I don't have pictures of that, but do have pictures of where I'm at. I have basicly traced my pattern onto my steel and gone from there. I cut the spring and the blade out and roughed them into shape.

slipjoint1.jpg


Today I started on the fixture that will hold the blade and spring and check it's zero points. It's bout half done. Here I have the blade and spring pinned into the little piece that fits in the slot in the fixture.

slipjoint2.jpg


Here I have placed the blade / spring into the slot and you can see the piece that will become the bridge for the indicator shaft housing sitting to the left. I still have to drill and tap that and also add a hold down tab for the sliding piece. I basicly built this thing like the ones I saw in Bruce Bumps pictures and Ryan Minchew's.

slipjoint3.jpg


That's all I have for this tonight, I'll add more later. Please join in and let me know what you think :cool:
 
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Today I have been cutting the liners and bolsters from 410 ss. I have 4 knives in progress at once, learning on the first one and applying the changes to the other three as I go. Here are some pictures of the liners already cut and the bolsters laid out and partially cut-

slipjoint4.jpg


slipjoint5.jpg
 
I finished the rest of the indicator holder yesterday and got it set up and working. I initially made the hold down arm where it came in from the bottom side, but I found out that it wouldn't work like that because the blade has to pivot and it can't as long as that is in the way lol. I felt kinda stupid. I still have to tap a hole in the top so I can mount it up there. For now I just hold the slide piece as I use it.

I worked on the blade / spring a little bit and got them flat and fitting at zero in all three positions. This really is a neat little fixture. In the first picture you can see the arm and how it would be in the way from the blade swing-

slipjoint6.jpg


slipjoint7.jpg


slipjoint8.jpg
 
I invested in some cheap tools to get started up doing this at home. The first couple of knives I made were done at work and it just kinda takes forever doing them on your breaks and staying late to do them and all. I work in a tool room so I have pretty much every tool need there. Now that I'm set up at home I can really make some progress and move forward.

I have a shop coming up in my back yard, but all I have done so far is the slab. It will probably be after the first of the year before I get it built, so until then I just set up a small work area in my spare bedroom. I lined the walls with medical pads and there is a shower curtain under the desk and coming out on to the floor. I want to try and keep the metal dust and sanding dust contained as best as possible.

Here is a picture of my little work station-

Desk.jpg


I don't really have much desk space, but I just move stuff around as I need it. So far I have a small 1x30 sander, a larger 4x36 belt with 6" disk combo machine, a drill press with 1/2" chuck, an old bench grinder, a vise, and a bandsaw. The majority of the tools came from harbor freight and they seem to be doing fine for now. I made and added a small table to the bandsaw. This thing is so loud it will wake the dead :eek:. I need to build a stand for it, but for now I just wedge it up against the other tools and support the handle with a piece of steel. Not the safest thing to do, but it will work while I progress.

I also have a 2x72 grinder in progress, but it will be a while before I get that thing going. I'll have to sell some knives first :)
 
Happy to be a part of your new addiction. Looks good so far. I'm waiting to see your makers mark so I can see what your name is. I guess I should already know that because we are working on something together soon, sorry but web handles are so impersonal.
Nice WIP here, good photos and explainations too. I'm surprised you didnt draw it on CAD but instead used the paper method like us old cad challenged makers. At least I've discovered mylar though.
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For all those wonderng, my name is John Sanford. I always tell everyone "like Sanford & Son" :D

Believe it or not Bruce, drawing something with a pencil and paper is much easier than in CAD because I have the ability to move lines and radii very easily. In CAD, it may take several key strokes and mouse clicks where as here I can flip the pencil to erase and flip it back over to draw.

Maybe later on I can finalize some of my shapes in CAD, but for now I'll just work with paper until I get something I'm happy with :bud:
 
I got some pictures of the pattern for yall. I couldn't find a needle to show the pivot action, but here is the pattern in two pieces and together.

slipjoint9.jpg


slipjoint10.jpg


and then...ladies and gentlemen, one of those trials and tribulations I mentioned? yeah. Here ya go lol

break.jpg


Maybe I can make it to harbor freight to get a few more blades before they close today..Unfortunately, my little bandsaw doesn't have a blade welder on the front of the machine like the big ones do :rolleyes:.
 
Thanks for the introduction John. If you are going to sell knives people need to know who they are dealing with.

With you knowledge of machine work and CAD you should be able to make a prototype like this one the paper method and write the program off of it for additional knife parts. I envy you having the job you have at work. It looks like you're getting a knife shop at home put together nicely.

I like Lenex Diemaster II bandsaw blades. Any blade will break if metal gets jammed in the blade. I finally made a new table with a super narrow blade slot.
 
Thanks for the recomendation Bruce. Lenox does make very good blades. The stuff we have at work comes on rolls and we just cut it to length and weld it. I've never bought the pre-welded blades before.

The problem I have is that for this kind of work you need something with really fine teeth. They can be hard to find. I was cutting some titanium the other day and for liners and that blade was rasing cain. It didn't hurt it, but apparently something made it break. I'm gonna take a look at it when I put the new blade on.
 
Today I have been cutting the liners and bolsters from 410 ss. I have 4 knives in progress at once, learning on the first one and applying the changes to the other three as I go.


This is a great idea John. I'm following BBs warincliff WIP and now yours and afraid I'll mess it up, multiples takes some of the stress out, plus applying changes will make for a quicker learning process.2thumbs
 
Today I have been cutting the liners and bolsters from 410 ss. I have 4 knives in progress at once, learning on the first one and applying the changes to the other three as I go.


This is a great idea John. I'm following BBs warincliff WIP and now yours and afraid I'll mess it up, multiples takes some of the stress out, plus applying changes will make for a quicker learning process.2thumbs

I've found this to be the best approach, especially for the first attempt at a new design. You can read about all the things that people experience when building them, but until you do it yourself it's hard to see what they mean. If you have a couple going of the same design at once, you don't have to worry about one wrong move ruining the whole project. When you become more proficient you can do more one piece at a time work.
 
hey J S

i gotta dewalt porta aswell... the blade it came with wasn't good at all..

do you have a lowes near you... ? if you do... they got Lenox wolfbands there that are made to fit... think they gottem down to 24.. over here its about 20 bucks for 3 blades

i'd love to do a slip, but i'm not brave enough yet.....


Greg 2thumbs
 
hey J S

i gotta dewalt porta aswell... the blade it came with wasn't good at all..

do you have a lowes near you... ? if you do... they got Lenox wolfbands there that are made to fit... think they gottem down to 24.. over here its about 20 bucks for 3 blades

i'd love to do a slip, but i'm not brave enough yet.....


Greg 2thumbs

Thanks! I started to go there but I didn't think they would have what I needed for this little portable band saw.

Don't be afraid of a slippie :)
 
http://www.lowes.com/pd_99732-28303-12088.0_0_?productId=1210205&Ntt=bandsaw%20blades&Ntk=i_products&pl=1&currentURL=/pl__0__s?newSearch=true$Ntt=bandsaw%20blades$y=0$x=0


i think i'm gonna try a slip... just have to get a drill press first... funny, how i never had one in the shop... guess i just got along without one for so long that i never bothered... ( either pistol drill or use the mill )


Greg
 
I would steer clear of the HF bandsaw blades. The one that came with my 4x6 broke before it even made it an inch into some annealed steel.
 
http://www.lowes.com/pd_99732-28303-12088.0_0_?productId=1210205&Ntt=bandsaw%20blades&Ntk=i_products&pl=1&currentURL=/pl__0__s?newSearch=true$Ntt=bandsaw%20blades$y=0$x=0


i think i'm gonna try a slip... just have to get a drill press first... funny, how i never had one in the shop... guess i just got along without one for so long that i never bothered... ( either pistol drill or use the mill )


Greg

Man if I had a mill that is what I would be using. I really want a mill, even if it is a small cheap bench top setup. We don't even use a drill press at work very much because they are so inaccurate. I just have one at home because I needed something that would drill a square hole and it does a pretty good job. As long as the indicator tells me it is straight I'll use it.
 
I would steer clear of the HF bandsaw blades. The one that came with my 4x6 broke before it even made it an inch into some annealed steel.

The brand is Morse I think, I forgot exactly what it is. There are three in the pack and they are made in USA. The only thing I don't like though is the teeth are too coarse. I think I'll take them back and get myself some of the Lenox blades from Lowes. Like I said, I didn't know Lowes had them. I have a Lowes about a mile from my house 2thumbs
 
hah.. i had a chuckle reading that... its exactly what i had in mind.. the drills now a days are such poor quality.. i usta go to the stores and check them out but i've been so let down... just extend the quil down and pull on it to see how much play.. usually bout 1/8 " .... ... i have a real hard time to stomach such sad quality...

- actually if its lined up perp to the deck then it should be good..but if the bit runs into any anomally in the steel... it may alter the drill path

i've been waiting for a nice clausing or borg... but i think i'm just dreaming

my mill is just a small taig... it does exactly what i need it for... .. but the chinese ones aren't bad with abit of set up and much cheaper

i've got the 18 tpi blades... bought 3 packs and i'm still on the first blade after 3/4 of a year after... even popped out a tooth cutting thin sheet and the dang thing still cutts..... isn't the rule of thumb to have 3 teeth on the stock your cutting..? anyhow... they also had the 24 tpi .... which i shoulda bought aswell...

these wolfband blades are a little stiff..... they not made to go around contours like the die master blades..... so i make all straight cuts and then buzz off the extra on the bader...

i wonder how these blades will hold up to stainless... i've cut abit of cpm d2 but that is all

Greg




Man if I had a mill that is what I would be using. I really want a mill, even if it is a small cheap bench top setup. We don't even use a drill press at work very much because they are so inaccurate. I just have one at home because I needed something that would drill a square hole and it does a pretty good job. As long as the indicator tells me it is straight I'll use it.
 
hah.. i had a chuckle reading that... its exactly what i had in mind.. the drills now a days are such poor quality.. i usta go to the stores and check them out but i've been so let down... just extend the quil down and pull on it to see how much play.. usually bout 1/8 " .... ... i have a real hard time to stomach such sad quality...

- actually if its lined up perp to the deck then it should be good..but if the bit runs into any anomally in the steel... it may alter the drill path

i've been waiting for a nice clausing or borg... but i think i'm just dreaming

my mill is just a small taig... it does exactly what i need it for... .. but the chinese ones aren't bad with abit of set up and much cheaper

i've got the 18 tpi blades... bought 3 packs and i'm still on the first blade after 3/4 of a year after... even popped out a tooth cutting thin sheet and the dang thing still cutts..... isn't the rule of thumb to have 3 teeth on the stock your cutting..? anyhow... they also had the 24 tpi .... which i shoulda bought aswell...

these wolfband blades are a little stiff..... they not made to go around contours like the die master blades..... so i make all straight cuts and then buzz off the extra on the bader...

i wonder how these blades will hold up to stainless... i've cut abit of cpm d2 but that is all

Greg

The two wire edm machines I run at work hold tolerance down to .00001". I think it is actually further, but you need very sophisticated measuring equipment to actuall "see" that. Think microscope.

This is why I have a hard time with anything that isn't acurate. The drill press from harbor freight is actually pretty impressive though, and does alot better with a keyless chuck. Anytime you have the choice of keyed or keyless, the keyless is usually better as far as runout.

With a mill I will use a collet if I can instead of a drill chuck.
 
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I made it little progress last night folks. I may have created an unfixable problem, but I did get a little further with the project.

First off, I took my 10 tpi blades back to harbor freight. I figured it would be better to get something along the lines of 20 or more tpi for cutting the very thin material. I was unable to find any portable bandsaw blades at three different home improvement stores, so I may end up ordering some.

I decided to move forward with the project and try to get the liners drilled to match the spring, and assemble the liners and blade / spring to see how everything worked. I haven't ground any bevels or even finished the blade profile yet.

Working from memory (trying to remember how I had seen it done in other WIP threads) I did the following. First I super glued my spring to one of the liners and drilled one of the holes through the spring into the liner. I then placed a dummy pin in that hole and drilled the other. I found out that super glue does not hold as good as I would like, and broke free during drilling on both sets of liners. I'm still unclear on exactly how to get the blade hole drilled because of the tension state cause by the spring. I just did my best and tried to figure it out.

I got all the holes drilled and to my suprise I got the liners and everything dummy pinned up. I may have done some of this a little bit backwards or not in the right order but hey, it's all about learning right?

I have a question for the pros. If I remember correctly, most other makers have already ground the blade and heat treated both it and the spring by this point right? I haven't and I am still working with a soft spring. Throughout this whole project, I couldn't help but think of one thing. Why not do all your hole work in your liners and all, and then bend the spring to create the tension needed and heat treat after that. In my mind, it would prevent you from having to deal with the tension issue and keep you from having to drill holes slightly off to "create" the tension once everything is pinned up. Does this sound like a logical idea, or am I off?

In any event, after I pinned everything up I got the knife working. It is kind of neat to feel the snap at all three positions. Talk about motivation 2thumbs. But, as I looked at the knife assembly and reviewed my work, I noticed that my pins are not in line at all. They are off bad. Real bad. I'm not sure what created this problem, but I wanted to list it here for the other people attempting this. This way, if they run into the same situation, maybe they will know how to fix it as I figure out how as well.

This is a picture of what I have. It is not the actual picture of the assembly (don't have that at the moment) but it is a drawing that clearly details the problem-

problem.jpg


I think maybe the guess work of trying to drill the blade holes in the liners seperately (one side, then the other) may have caused it. But even then, the two holes in the spring don't line up either. Not really sure what happened, but the only thing I can think of to fix it is to clamp the hole assembly together, and drill one hole at a time out bigger. This would work fine, but my holes are already 3/32, and I don't want larger pins. The only fix may be to start over with new liners, but thats ok, because I have plenty more that I cut. I'll post some pictures tonight of the progress in each step listed above. It was getting late last night, and we all know how long it takes to get from camera to here with pics..
 
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