Another home made engraving machine

[jan-willem]

Necj,

I had no idea the parrot was done without power assist. I really know little to nothing about bulino and its requirements. Makes it all the more amazing.

I was confused about the manner in which you control your machine until I went back over your video's and found the foot pedal. Now I understand! That makes better sense to me than just choking the airflow directly to the hand tool. Awesome!

I am also happy to hear the compressor is tough enough and the tubing stays in place. I saw the video on your custom made handpiece. Very nice. I already researched some metalshops near me and I think it should be possible to have one made if the knockoff should fail. Do you mind sharing dimensions, tolerances, surface treatment of your handpiece design with me?

I agree with you on the investment when compared to the proffesional tools. Thankyou very much for answering my questions. With the knowledge shared by Shaun, you, Elvis and others I am confident I can build one myself and will be ordering the parts this afternoon.


Elvis,

Thanks for getting back to me! I think the numbers just show the value of the pot from 0-100. as you said its just handy as a comparative reference. I did check out Necj's pedal and I agree that seems to be the best solution. With a pedal setup such as that the system will never be fully constricted but its good to know that even with fully closed tubes the system has more then enough power to deal with it without things breaking badly. That is actually important to me so I appreciate this feedback greatly.

I think your work looks gorgeous. I am personally a bit of a stickler when it comes to "knowing" about styles and rules. Hence why I am the opposite in my approach. I watch dvd's and books before I even attempt a full decoration. While its part of who I am and i've come to accept it I am often a little jealous of the people who just go with the flow and have the guts to freehand like you. I am an analytical person by nature and its easy for me to fall into the trap of reading just a little more, doing a little more research, or practicing a specific part of a design instead of just drawing. I definately don't think less of your art because you are approaching it more freely.

Thanks again. I hope to have build my own engraver soon!


MoldyJim,

It seems I jumped the gun as well. I was afraid your and Monk's reply would smother the thread instead of keeping the discussion going so I could make up my mind on whether to undertake this DIY project or not.

I clearly misinterpreted your reply. I am sorry for the confusion caused and am glad you did not take offense. I am also encouraged by hearing we got another "hobby" engraver with their own DIY engraving setup.

I have decided to purchase the parts and assemble one myself. Hopefully I can do more than talk about engraving soon and I look forward to sharing my first practice plates with you all!

Kind regards,

JW

 

[MoldyJim]

No worries,
I am maybe a little hesitant to broadcast too much about DIY tool on the forums.
Too much commercial conflict might cause problems.
GRS, Lindsay, etc are in business to sell tools.
Thank goodness, I applaud their successes and love having fine tools.
But...
For me, half of the fun of any hobby is making my own tools (if not more)
I have two perfectly good engraving vises, one vintage, one a nice new import.
Still, I am working on a heavyweight, low profile vise design from salvaged parts.
I have a set of the beautiful GRS chasing hammers, but still use a couple of homemade hammers for chiseling.

My drive setup is really simple.
A sewing machine motor with foot pedal, belt drive to a pully on a 1" piston/cylinder.
No valving, just a tube to the headpiece.
Piston goes up, pushes 3/8" hammer piston in headpiece into back of the toolholder.
Piston goes down, pulls hammer back and starts over again.
Speed controlled by foot pedal.
A good balance between piston sizes and its easily controlled, change to lighter piston for fine shading lines.
Not clear about pinching the airflow, is that because the rpm is constant in your machine?
Or to lighten the impact?
Jim

 

[Victorvile]

Hi Jim ,could you pls, post a sketch with dimensions of your setup?,thanks.

 

[Brian Marshall]

Most of the important basic patents are expired or about to expire.

I wouldn't worry about offending the commercial companies until you actually decide to become competition.

What you are doing is exactly what is needed to discover the next generation of tools...


Brian

 

[Elvis]

Jim

Jim, I don’t think us do-it-yourselfers are too big of a threat to the industry. I certainly don’t think my home made engraver can compete with the well-engineered, well made commercial systems that are available today. They are far superior to anything I could make. If I were to ever get serious about engraving, I would definitely look into one of these systems. And who knows – maybe messing around with this home-made machine will lead me to that conclusion. But like you, I really enjoy making my own tools – tinkering around in the shop and figuring out how things work. For me, it’s definitely more than half the fun. I too have a nice set of commercial engravers and a nice well balanced chasing hammer but when it comes to engraving I find myself using the old engravers that I forged from a hay rake tine 15 years ago and a ragged ball peen hammer I found at a garage sale for 50 cents –and they work just fine for my purposes – perhaps I am just used to them. Being brand new at pneumatic engraving, I certainly have a lot to lean – even about the machine I have made. I haven’t made a foot pedal for it yet and have up until now been controlling it solely with the speed control dial. The dial controls the rpms of the motor and is variable. This is somewhat awkward because you have to set the dial to the desired rpm and then it usually takes both hands to engrave with (one to turn the vise and steady the work and one to hold the graver). So you have to begin and end the cut with a vibrating engraver and if you want to go deeper in the middle of a cut there is no way to speed up the hits without stopping and re adjusting the rpms. As far as I can tell from others who have posted on YouTube about this type of machine, a foot pedal (which I intend to make) is used to restrict the air flow which in turn controls the intensity or power of the cut – basically less air flow-less power to the hand piece piston and graver. My first thought was to simply rig up a pedal that works the speed control dial – like your sewing machine pedal. That way the pedal would simply control the motor rpms and the piston would start out slow and increase in speed as the pedal was pressed. But from what I can tell (and I am not speaking from experience here – just inference from what I see on YouTube) there may be an advantage to using the air restriction method. By setting the speed control at the maximum rpms for a cut and controlling the intensity of the cut by restricting the air flow it may be possible to get a smoother cut since the rpms and number of piston hits basically stay the same regardless of how much air is getting to the piston. In other words, say you set the speed control on 100 rpms and this results in 100 piston hits in the hand piece per minute when the air flow is unrestricted - this would be the most intense cut you could make with this setting. As you restrict the air flow by pushing the pedal or squeezing the air tube, the cut becomes less intense but the rpms will still be the same as well as the number of piston hits. The piston hits will have less power because of less air but they will be the same in number as a cut made without air restriction. So even the low intensity cuts will be made with lots of small cuts which maybe will make the cut a little smoother? Please take this all with a grain of salt as it is only speculation on my part. I am sure that Stick (Necj) and others who have more experience with these machines would have much better insight on this. As I make a foot pedal and mess with mine some more I will let you know what I find out about this. Sounds like you have a good simple set up that works well for you.

 

[jan-willem]

MoldyJim,

glad to hear that. Your setup actually sounds very nice! I could not find the video anymore but I know Shaun created a setup just like you described, as an experiment, which was hand driven (he just spun it by hand) and it displaced enough air to make the handpiece knock! I thought it was brilliant. I think because the displaced air volume better matches the handpiece it also functioned slightly better at a bigger rpm range.

I think most of use realize the 150psi air compressors are overkill for this application and I am certain the displaced air does not match the handpiece properly whatsoever. So your approach is much more elegant in my eyes.

So far I've seen two ways to control the impact of the handtool of the DIY setups that I know of (with "fixed" rpm). One is indeed restricting the airflow. The other approach (Necj's) is based on having the air flow away freely (so it is not forced to go into the handpiece) and controlling how much air is allowed to escape (with full power forcing all air to go to the handpiece).

I feel both these methods are hard to DIY. With hard I mean do properly, where you have an actual range in your pedal. With Necj's approach it seems like milimeters, with Shaunds its the thickness of a tube. Its because of this that I've also been looking at a sewing machine pedal. If you control the airflow with a servo driven valve you can map the pedal and use a bigger range. Thats a little "advanced" but my mind goes weird places sometimes. I bet its quite possible to do that in a purely mechanical fashion as well but I find it easier to connect wires then to have to create correct leverages and gears etc. :clapping:

Now I have only tried GRS which I know for a fact works with a fixed stroke per minute setting. You set the strokes per minute and the footpedal controls how much pressure goes to the handpiece. However ive seen video's of the Enset system which seems to be fully rpm driven. I am uncertain about the lindsay system. So that would indicate both approaches can work.

As for the "big brands; I thought this was an open forum, not owned by any of them so I am not exactly worried.

The market they are in is one of high margins and it shows in their product prices. I highly doubt a starter setup needs to be as complex and expensive as their cheapest offerings but there probably is no money to be had in the simple consumer market so they have no reason to develop a product to match. I have no doubt in my mind they could develop an engraving machine for $300 that requires no separate compressor, is whisper silent and blows all our efforts out of the water. We won't be seeing it until the off brands start to eat into their market. With as big a niche as engraving is, I don't see that happening anytime soon. So its back to DIY for us!

JW

PS
Please note I am not saying the $300 starter setup would be equal to the 2k variants. That would be silly.

I found the video about the hand driven graver! Its aptly titled "Engraving system for the apocalypse!!" ITs obviously a really rough setup but it works! https://www.youtube.com/watch?v=oJQR1q_0HYA

 

[jan-willem]

This also looks very interesting to me, especially when it comes to sound. Using an airbrush compressor. These are obviously much lower power but if its enough to move the piston in the handpiece...

https://www.youtube.com/watch?v=tqfCNDwZesg

Even with the horrible pedal (sorry Shaun) it seems to react extremely well. Imagine using a proper sewing machine pedal or something similar with it.

And that would be only RPM controlled. I am quite curious why Shaun did not continue with this one. Did he find a flaw with it?

 

[MoldyJim]

I'll try to take some good pictures tonight.
I'm not worried about Patent rights, I don't plan on selling these things, they are pretty simple to make up from salvaged parts.
Plus, the machine I started with is made from an old dental tool, the patent had to expire decades ago.
I think it was used to tamp gold foil into cavities.

It is the same principle as 100 year old Pneumatic power hammers, Big piston moves up and down, pushes and pulls on little piston, little piston taps on work.
Just made on a much smaller scale.

Mainly, I don't want to step on the toes of people that make their livelihood selling tools.
Anyone that invents a product, patents the idea and successfully brings it to market deserves my respect.
I am no fan of counterfeiters or ripoff artists.
But I am a toolmaker, if I can make a tool that I need myself, I get the benefit of saving money, gaining insight, and learning from the experience.
Then if I decide to go at it more professionally I can decide to make an investment in fine tools.\
But to each their own.

 

[jan-willem]

Hey MoldyJim,

I'd still love to see your setup in a bit of detail. Its quite different from the others and I was looking forward to seeing some photographs. If its not too much trouble of course.

JW

 

[MoldyJim]

Sorry, got sidetracked with other things.
I'll take some pics tonight.

 

[MoldyJim]

Okay, lets see if this works,
The first one is the whole setup with four handpieces, two on the left dismantled.
Leftmost heavier brass piston. Next is light aluminum piston. Both toolholders are made from old dremel shaft and collets.
Last pic is the little motor that could...
Really simple, motor goes round and round, piston goes up and down, air goes back and forth.
Boom. Engraving.

 

[MoldyJim]

Here is box "O" stuff engraved using these tools.

 

[Brian Marshall]

So you never felt the need to make actual palm style (think mushroom) handles for ends of these tools?


Brian

 

[dogcatcher]

That is great work, a piece of art. I love the use of the Zerks for the fittings. The Zerks also make great propane burner heads for prickly pear.

 

[MoldyJim]

I have stuck a big cork around one for a while but not really needed.
Seems to work better when you don't push just follow the cut.
It's like it will only cut so fast, if you push hard, it holds the collet to hard in the bore and doesn't allow the impact to move the tool.
There are two O rings that the collet rides against.
One inside the bore, and one behind the step on the shaft. Holder bounces back and forth slightly against the O ring bumpers.

 

[MoldyJim]

That is great work, a piece of art. I love the use of the Zerks for the fittings. The Zerks also make great propane burner heads for prickly pear.

Prickly pear? Not sure what that is. Conjures up some interesting ideas tho.

As to the zero fittings,
A while back we ordered a dozen.
They sent a dozen bags of fifty.
Yet they were so cheap it wasn't worth sending back for refund.
So...
They were available, easy to modify, and free.
Sounds like a winner to me.

 

[dogcatcher]

Prickly pear is an invasive cactus that sucks water out of the ground and spreads if not controlled. During draughts the ranchers also burn the cactus spines off the cactus so the cattle can eat it. Wildlife will also eat prickly pear. Here is a pic of a guy ready to burn prickly pear using a pear burner.

It also works good for melting ice on the sidewalk.

 

[pLM]

Hi there,

I'll post my homemade engraving setup. It has both foot control and strokes per minute regulator. Handpiece was made on lathe. If someone is intrested I got handpiece plans somewhere. Whole setup is ~200Euro/250$.

here is the handpiece

Here is my work done with this baby. Im kinda new to engraving so dont be harsh please It can handle all the work: engraving, stonesetting, sculpting, inlay etc

 

[MoldyJim]

Wow! that's nice work.
Is the motor 12V DC with a transformer and bridge rectifier?
Very cool.

So many different ways to catch a mouse.

 

[jan-willem]

MoldyJim,

Thank you for posting the photos! What en elegant setup. I don't think you could make it any simpler even if you tried! Very nice! :clapping:

Your box of stuff looks like a treasure chest. I love the contrast on the black knife, it looks beautiful!

PLM,

I think your engraving looks great! Very smooth.

I am curious what role the pedal plays in your setup. Since its an electric pedal does that mean it controls the rpm in addition to your spm regulator? Do you set a max spm with the regulator and use the pedal to go from 0 to limit?

I love seeing all these different kind of setups.

I've found some very detailed drawings of a custom handpiece on a russian forum for toolmakers. Hopefully that will give me enough info. All dimensions are metric and provided with tolerances. The only thing I am not 100% certain about is the material definitions. It doesn't help that I don't speak a single word of Russian and the drawings are in png so I cant exactly past the words into google translate.

Oh well. The ordered parts should arrive in a week or two. Plenty of time to draw the design myself in CAD, possibly simplify it here and there and see if I can find a metal shop nearby who is willing to give it a shot.

Thanks again MoldyJim and everyone else for posting your setups. It gives me great confidence that with some tinkering I might be engraving soon as well.

JW