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Mike Audleman
04-07-2017, 1:52 PM
I know I have been absent for quite a while. Well, because the laser has been too.

I am finally getting around to swapping out the laser tube that failed in 2015. Yea yea, it hasn't been a priority. Not really one now either but I finally got my round 'tuit.

So I ordered a tube off ebay and should be here next week, so I will give it a go.

Is there any docs on laser tube replacements? Never done one so its a new ball game for me. I was a UHF TV RF engineer so I got all the safety things down when messin with KV power. Its been powered off and unplugged for 2y but I will still verify no HV before touching anything. You usually only get to screw things up once before your widow gets all your stuff. Other than that, anything I should watch out for or be careful of? And general tips on bringing a new tube online for the first time?

Bill George
04-07-2017, 4:19 PM
Hi Mike, nice to see you back. Its been off for 2 years, no issues but if you want to take a jumper and ground the HV lead for your own piece of mind. Take a picture or two of how the tube is installed now and just R&R, make sure the electrical and hose connections are the same as the old. Make sure you have water flow before powering up the unit. If you have a mA meter in the ground side of the tube you can make sure your not overdriving it. I purchased my new tube from LightObject and it had lots more power than the old one ever did.


I see you still have your 3D printer.

Mike Audleman
04-07-2017, 6:29 PM
I am quite sure the HV is dead by now. But, as I said, you only get to be wrong once. Dumping it across an incandescent bulb is an easy peace of mind. And, yea, lots of photos, especially of position so I can get it back in the mounts in a similar position.

Looked there. They didn't have one labeled as 50w and nobody got back to me from their email link. So I got this one:
http://www.ebay.com/itm/282385158010
I contacted them to confirm it fit my machine and they said yes. Will see when it arrives I guess.

Still workin the Taz to death. Printed so much stuff its nuts. I have no idea how I would have put on my Halloween or Christmas light shows without all the 3D printed parts. From mounts for the flood lights to attachment clips on the 20' megatree.

I have videos up of some of the 3D prints as well as videos taken of the Halloween and Christmas shows. If ya wanna look:
https://www.youtube.com/user/MikeAudleman

I am wanting another printer and the one I want is the prusa original i3 Mk2. Been holding off on it as its 1.75mm filament only. And I have dozens of spools of 3mm for the Taz. Will likely hold off until I exhaust most of the on-hand stock before getting the new printer. Then I will make a 1.75 head for the Taz and convert it so both will take same size filament.

Bill George
04-07-2017, 8:06 PM
As I recall there is really no such thing as a 50 Watt tube, there are good 40 watt ones that can be over driven, but not for long. Key is the length of the old tube and space for it to install or fit in. LightObject dot com I think they either have that info on the website or you can read what they have to sell. That is one reason you did not see a 50 watt listed! Your eBay vender lists your tube at 850 and 1000 mm or 39,,, inches.

A lot of new tubes get broken in shipping..... so be aware.

Mike Audleman
04-10-2017, 4:35 PM
As I recall there is really no such thing as a 50 Watt tube, there are good 40 watt ones that can be over driven, but not for long. Key is the length of the old tube and space for it to install or fit in. LightObject dot com I think they either have that info on the website or you can read what they have to sell. That is one reason you did not see a 50 watt listed! Your eBay vender lists your tube at 850 and 1000 mm or 39,,, inches.

A lot of new tubes get broken in shipping..... so be aware.

What sorts of things should I look at? I assume obvious stuff like outer package damage and any obvious glass breakage. Anything else to look for?

Bill George
04-11-2017, 9:09 AM
What sorts of things should I look at? I assume obvious stuff like outer package damage and any obvious glass breakage. Anything else to look for?

Mike the one I got, was in a huge cardboard box and surrounded by foam. The tube was perfect, Does your eBay vender say anything about shipping damage or who pays? I do not think you could tell by the box, unless it was really in bad shape.

Mike Audleman
04-11-2017, 10:28 AM
Mike the one I got, was in a huge cardboard box and surrounded by foam. The tube was perfect, Does your eBay vender say anything about shipping damage or who pays? I do not think you could tell by the box, unless it was really in bad shape.

Just curious, what was your damage if it wasn't physically damaged?

Bill George
04-11-2017, 12:24 PM
Just curious, what was your damage if it wasn't physically damaged?
Tube was perfect, no damage but it was shipped from US, west coast.

Mike Audleman
04-11-2017, 3:22 PM
This one is coming from Tennessee. I purchased from a retailer that has US stock. Didn't want to risk the shipping from China.

Mike Audleman
04-11-2017, 8:30 PM
Ok, the tube came today. Packaging seems ok. It was a fairly heavy cardboard box lined with styrofoam. The ends of the tube were wrapped with a type of bubble wrap so they seemed to package it well.

I have the tube mounted and wired. I had to tip the tube to get the bubbles out of the water chamber and re-secure it. Live and learn. The machine came with a tube of silicone caulk so I used that. Not sure how long it takes to cure so I will leave it sit until tomorrow to make sure its had enough time before I apply any power to the tube.

The label on the new tube says it was filled Feb '17. Don't know if thats accurate or not. Old tube had no such label.

I swear they mounted the original tube before assembling the cabinet. There is no freakin way you can get to the back screws on the rings. Not with any screwdriver I know of anyhow. I managed to get them loose enough and got the front two off so I was able to twist the upper ring off and over the old tube and back over the new one. Not a good scenario. I think I will look at designing up a different tube mount ring and 3D print it before I replace this tube again.

Guess its now a waiting game waiting on the silicone to cure.

So, is there any value to the old tube? Its outer shell is cracked at the cathode (output end) all the way around so it can't simply be refilled or recharged. What should I do with it? Garbage? Is there any consideration on it as hazardous waste? I don't think its anything but glass and a couple bits of metal and some CO2 gas.

Doug Fisher
04-11-2017, 8:47 PM
>>What should I do with it?<<

I think a "roof test" where you drop it down on to the concrete below (making a video to post here of course) would be the best course of action.

Bill George
04-11-2017, 9:30 PM
Well my old tube was not broken, just weak. I saved it for a long time, then one day I put in in a large garbage bag, used a hammer to make little pieces and that was it.

Mike Audleman
04-11-2017, 10:31 PM
>>What should I do with it?<<

I think a "roof test" where you drop it down on to the concrete below (making a video to post here of course) would be the best course of action.

Haha! Nice. Unfortunately, then I have to clean up the glass so I, my dogs nor my granddaughters cut ourselves. I like the idea, but the cleanup makes it not so much fun. And our range doesn't permit us to shoot glass objects, obviously for the same reason so there goes that idea. I could easily make it go away big time at the range.

Shame the water jacket is cracked. Would make an interesting "tap" for the coffee maker at work :)

So I presume its basically safe to dispose of as you would any other glass item.

Mark Taylor2
04-12-2017, 12:19 AM
Mike,

Call your local disposal company. Ours takes TV tubes (color) for a fee, BW at no fee, and laser tubes at no fee. It may be that your disposal company might charge to take it.

Mike Audleman
04-12-2017, 12:52 PM
It lives!

Got the tube in last night. Checked this morning and the silicone seemed hard so I did a few tests and 10/20/30% power pulses. It all seemed ok and it didn't complain. The alignment is off a bit. The beam is well above center on the mirrors but there is not change in spot position as the gantry is moved so its all straight and parallel. I think the tube mounts are simply high. Not sure how to fix that. Yet. Had to go to work.

Ran the quick test with a file in memory at 10% power just to see if it would attempt to work. And it did. So, now I need to do a proper align and test higher power settings on something more challenging that posterboard.

http://cdn.ipernity.com/200/54/62/44615462.6deae6bf.500.jpg (http://www.ipernity.com/doc/wolfie/44615462)

http://cdn.ipernity.com/200/54/60/44615460.cb63dc93.500.jpg (http://www.ipernity.com/doc/wolfie/44615460)

Roger Lueck
04-15-2017, 1:27 AM
>> I swear they mounted the original tube before assembling the cabinet. There is no freakin way you can get to the back screws on the rings. Not with any screwdriver I know of anyhow. I managed to get them loose enough and got the front two off so I was able to twist the upper ring off and over the old tube and back over the new one. Not a good scenario. I think I will look at designing up a different tube mount ring and 3D print it before I replace this tube again. <<


You are correct the back screws on my Chinese laser are a PITA also. The intent is to replace the mounts when I replace the tube in the next couple months when the current one dies.
Could you post a photo of your tube mounts, I'd like to see what you design to facilitate ease of removal/installation as well as the ability to adjust the tube alignment and height.

Mike Audleman
04-15-2017, 2:31 PM
>> I swear they mounted the original tube before assembling the cabinet. There is no freakin way you can get to the back screws on the rings. Not with any screwdriver I know of anyhow. I managed to get them loose enough and got the front two off so I was able to twist the upper ring off and over the old tube and back over the new one. Not a good scenario. I think I will look at designing up a different tube mount ring and 3D print it before I replace this tube again. <<


You are correct the back screws on my Chinese laser are a PITA also. The intent is to replace the mounts when I replace the tube in the next couple months when the current one dies.
Could you post a photo of your tube mounts, I'd like to see what you design to facilitate ease of removal/installation as well as the ability to adjust the tube alignment and height.

I am working on a new mount design right now. Just beginning the process. Is your rear area 106mm deep and 131mm tall. The top overhang is 35mm and the bottom lip sticks up 13mm.

I put up some photos of the rear tube area here:
http://www.ipernity.com/doc/wolfie/album/973282

Dave Sheldrake
04-15-2017, 11:27 PM
800mm is a 38 watt,

850-860mm is a 40 watt

1,050mm is a 50 watt

1,220mm is a 60 watt

Running an 800mm at over 14mA will kill it very quickly :(

On the ebay page it says 800mm, 850mm and 1,000mm all on the same advert

Mike Audleman
04-16-2017, 1:31 AM
800mm is a 38 watt,

850-860mm is a 40 watt

1,050mm is a 50 watt

1,220mm is a 60 watt

Running an 800mm at over 14mA will kill it very quickly :(

On the ebay page it says 800mm, 850mm and 1,000mm all on the same advert

Once again the cat supplies very useful info!

The tube I pulled out (not knowing for sure where to measure) is 32-1/4" end to end measured from the outside of the glass at each end. That comes to 819mm. The pins (anode and cathode) are almost exactly 30". There really isn't a measurement thats obvious that is 31-1/2" (roughly).

Thing that I can't find marked on the 50w PSU is the output voltage and I don't have a HV DVM to measure it. Knowing the amps doesn't tell me the power consumed without the voltage. Suppose I could solder up a 100:1 resistor network and measure the voltage across that and get a rough idea. Then I could back convert to mA for 38w, 40w and 50w given what the PSU is supplying.

An ammeter is next on the mods list after I get this tube mount finished. Given the "ground" name I see on wiring diagrams, this is DC. I have a few old analog ammeters. Need to dig through the bin and find one with the right mA range. Hopefully a 0-50 which would suit the box if I upgrade the tube to a 60w at some point.

Is the "ground" off the tube actually a ground? I mean is it actually tied to the chassis ground or is it floating?

My instinct is to put the ammeter in the ground line as it has less voltage potential. Do you know if the KV from the HV lead would appear on the ground lead if the connection between the PSU and the ammeter should be severed/broken? If so, then I will have to insulate the rear of the ammeter case against KV potential. The wire used in this machine for the ground lead does not appear to be insulated against KV potential and looks like standard 400-600v hookup wire. Half thinking I should replace it with KV rated wire if the ground is floating.

Dave Sheldrake
04-16-2017, 11:55 AM
the return wire is fine at the guage it is :)

The tube is a base 40 watt at that length, voltage between a 35 watt and a 60 watt is only 1 KV difference so no biggy, current though is important, drop an analog meter into the return line, make sure you don't go over 14-15mA MAX though Mike. You can reduce current either on a Pot through a small hole in the PSU (some models) or on an internal Pot inside the PSU (on others)

Those machines from Keuhi are well known for having the current pumped up to get 50 watts from a 40 watt tube, it tends to burn them out pretty quickly :(

0-50 mA will cover all tubes up to 280 watts :)

Mike Audleman
04-16-2017, 12:00 PM
I hope you post photos of how you mount your laser tube as I will be replacing mine in the next couple months. You are correct, the screws in the back are a PITA,


Design Goals:

Fit my machine and tube
Solidly support tube
Can be installed without modifying the machine
Can be installed without being an octopus
Tube easily installed and removed
Easy to adjust tube position at any time
Use mostly common materials (preferably what I have on hand)
Easy to reproduce
Can be adapted for additional tube sizes (upgrades later)


Here is the design I came up with:
http://cdn.ipernity.com/200/92/46/44639246.653b92ff.500.jpg (http://www.ipernity.com/doc/wolfie/44639246)

https://www.youtube.com/watch?v=PWiKpKNmNiA
I rendered it out with various colors of glass material so its easy to see the different pieces and how they will go together. I will be printing mine from PETG all one color.

I am still tinkering with the fiddly bits but I have tested a preview print of the outer frame and the inner holder. The outer frame fits perfectly in my laser tube compartment. The tube holder is a little tighter than I want so I am re-printing it. Luckily I didn't dispose of the old tube so I have it to easily test the fixture with :)

I looked at several designs already out there and took clues from them to come up with my design.

The first was this one:
http://www.thingiverse.com/thing:420853

I liked the adjustment ability. Obviously he did get it mounted but I haven't a clue how. The C faces in and on my machine, the mounting tray is threaded so the screws must be put in from the top. I wasn't totally excited about the wireties either. From this design, I kept the outer/inner frame concept and the idea of the knobs.

The other item I took cues from was at about 20:30 into this video:
https://www.youtube.com/watch?v=NVzCMIq8dlc

I haven't laser cut any acrylic as yet (well, not successfully) so I am sticking to what I know. 3D printing. But I liked the compression ring he made with the 3 pieces of tubing. So my inner ring design incorporates that concept.

The result:

The outer frame can be installed in my machine from the rear and fits nicely. And, if you want to fidget you CAN install it with the tube in place. It does fit around a tube thats currently held in place with the stock brackets. Not easy. Can be done. Not a requirement of the design but more of a "hey, that works" option.

Once the outer bracket is screwed down every other operation can be easily completed. The tube can be put into the frame easily because the front of the square support goes on last so its an open C until the door is in place. The rings are loosely attached to the tube prior to putting it in the frames. Then you can access the bottom screw to tighten it once in the frame.

The door goes on last once the tube is in and is attached to the frame with a couple hex head cap M4's.

The hangar screws are standard M4 cap screws. There will be M4 nuts against the tube ring to lock the screws. Adjustment knobs contain a M4 nut. I used M4 heat set inserts in most areas. See the pattern :) Everything M4. That means you only need one allen wrench and a small open end wrench (or crescent or needlenose) for the locking nuts.

I beveled the bottom rear corner of the outer frame so your ground wire can be captive behind it if you wish. I am not sure if I will captive my ground wire there or not.

The designed parts will nest and print in a single run on my printer (though I have been printing each individually during the testing). I haven't tried but I bet I could get two on the plate if I tried hard enough.

Mike Audleman
04-16-2017, 8:00 PM
So here is the first full print:

https://www.youtube.com/watch?v=wk0ONeeG2o8

Being Easter, not sure I will have time to do much more with it today. Will get the heatsets installed and collect the other hardware I need for a final in-cabinet assembly test. Assuming that goes well, I should be able to get a WIP thing published to thingiverse sometime this week.

If anyone has any thoughts on changes speak up.

Roger Lueck
04-16-2017, 10:44 PM
Mike,

Attached is a sketch of the dimensions for the laser tube compartment on my machine. It appears the space on my machine is very similar to yours, probably made by the same Chinese manufacturer, just different colored paint and name.

Roger358426

Mike Audleman
04-17-2017, 10:33 AM
Mike,

Attached is a sketch of the dimensions for the laser tube compartment on my machine. It appears the space on my machine is very similar to yours, probably made by the same Chinese manufacturer, just different colored paint and name.

Roger358426



It appears like your compartment is much deeper than mine. I only did rough measurements with a MM ruler but I am pretty sure I wasn't off by 20mm. I will prep the compartment dimension test STL tonight and attach it here for you to download and print. Right now it doesn't have marks on it for either front lip or top overhang but I wll add those to it. Then you can quick print it and set it in your compartment to see how yours relates to mine. Yours being bigger is better :) If your measurements are right, and mine are too, yours is about 20mm deeper. If that is indeed the case, the mount will fit yours very easily.

Mike Audleman
04-17-2017, 9:42 PM
Here is the work area template I made that fits comfortably in my compartment. I have marked the upper open area and the lower lip

358492

Mike Audleman
04-17-2017, 11:01 PM
I got the heatsets installed on both brackets tonight. Unfortunately, I am out of longer M4 screws so I will have to hit the hardware store for some more before I can complete the assembly and swap out the old tube supports with these.

In any event, the first test fit went pretty well. The tubing I had selected was too stiff for my liking and the local science store didn't have the right diameter silicone and the latex tubing they had was too squishy and I felt it didn't support the tube rigidly enough.

But they had some gray 14" x 4" x 1/4" sticky back foam pad and strips of that seems to be a good fit. Holds the tube well without a lot of pressure so it should allow for any heat expansion and should make a nice vibration dampener. $1.50 well spent.

http://cdn.ipernity.com/200/98/70/44649870.14e92a2f.500.jpg (http://www.ipernity.com/doc/wolfie/44649870)

http://cdn.ipernity.com/200/98/68/44649868.80ecf871.500.jpg (http://www.ipernity.com/doc/wolfie/44649868)

http://cdn.ipernity.com/200/98/66/44649866.d84597fa.500.jpg (http://www.ipernity.com/doc/wolfie/44649866)


The tube clamp is screwed down to the tube and will hold it fairly firmly without undue pressure on the glass The outer frame is not (lack of long M4 screws). But in position, everything looks spot on for alignment and fit.

The tube is fairly well aligned as it sits now so the position once the new supports are put in place should be about where it is now. But I want to look into Russ's methods on tube alignment and these adjustable fittings should make that an easy task to properly square the tube up with the gantry.

Mike Audleman
04-20-2017, 11:31 PM
I got to the hardware store. I wanted M4x30 all thread but they didn't have any. Longest they had was M4x25. But I think its just long enough. Barely.
Here is my assembled tube:
http://cdn.ipernity.com/200/57/58/44665758.3aa6e642.800.jpg (http://www.ipernity.com/doc/wolfie/44665758)

This photo album shows the assembly steps:
http://www.ipernity.com/doc/wolfie/album/974382


All in all, it took be a bit over an hour to assemble everything. Would have taken less time if I had collected all my tools in one place, had finished putting the clips on the annode and cathode wires (so they are easily removable) and wasn't taking photos during the assembly :) And, it would have taken even less time had I remembered to attach the hoses and bleed all the air out of the tube before mounting it (nudge nudge wink wink). I had to remove the tube, bleed it, and re-insert it. To remove the tube, you only have to take the top hangar screw out of the ring and remove the two door screws on each bracket. The tube will then come out in one piece easily.

As you can see, I decided to run the ground wire inside the outer frame so its a very easy task to lift the tube out as a whole without undoing the connections in the event bubbles do form later.

John Lifer
04-21-2017, 9:29 AM
Nice. So are your brass inserts closed bottom? I see a nut on top of the insert, guessing locking into position. You are not going to be tweeking on this thing often, but if the insert is open to the tube, be mindful!!!!!!! that nut could loosen over time and you would have a bad issue. Otherwise things look good. Minor adjustments can be done to get perfect.

Mike Audleman
04-21-2017, 11:26 AM
Nice. So are your brass inserts closed bottom? I see a nut on top of the insert, guessing locking into position. You are not going to be tweeking on this thing often, but if the insert is open to the tube, be mindful!!!!!!! that nut could loosen over time and you would have a bad issue. Otherwise things look good. Minor adjustments can be done to get perfect.

They are open. Frankly I wasn't aware there were closed inserts :)

And yes, the nut locks the screw to the ring so it can't turn as you adjust the thumb wheels. After adjusting the tube, you then lock it with the 2nd thumb wheel. So both the wheel AND the nut would have to work loose in the same direction (out) and work loose sufficiently enough for the screw to also work loose in the completely opposite direction (in) to allow the screw to get to the tube. Frankly I don't see that happening :confused:. But if thats a worry, I think a dab of removable LocTite (blue or purple) on the screw before running the nut down against the ring will take care of it.

Before I post the STL, I will be closing the screw hole on the inside. Right now the hole goes through into the inner tube area of the ring as I wasn't sure yet whether I was going to put a nut in from the inside or one on the outside or put the brass insert in from the inside or the outside so it was easier just to blow the hole all the way thorough on the prototype. After I close that, you would have to screw the screw through the plastic before it actually reached the tube.

Also, the inner diameter of the mount ring is 55mm. The tube is 50mm. So thats another 2.5mm clearance you would have to drive the screw before it could impact the tube.

Could you drive the screw in and shatter the tube? Yea, if it were long enough. M4x25 aren't long enough to reach the tube, not positive about M4x30 but I don't think so. I would have to get into the mesh app and measure from the outside of the frame to the tube surface and see what the shortest screw would be to reach the tube. But I am guessing that if you got the smarts to be able to print the parts on a complicated 3D printer with really HOT parts, dismantle your laser cutter without killing yourself on the HV, install the new mounts, mount the tube and ultimately align it correctly, I presumed you got the smarts not to screw a 6" long piece of all thread into your glass tube :p

I presumed a certain level of intelligence given the tool its designed to fit. I was going on the assumption that the type of person using this was not the type of person they printed "Open Here" on the top of cereal boxes for. Its not idiot proof. But, I didn't design it for idiots. :D


After I make some last minute tweaks to the design I will get the STL up on Thingiverse. I needed to enlarge the holes in the base of the outer frame as the mount screws they used on the original brackets were larger than I thought they were (M5 or M6, haven't measured them yet). And close the holes in the tube ring. Other than that, I think the design came out quite well.

I aligned the beam last night. I put 4 pips in a piece of poster board with the gantry moved to the 4 extreme corners and the pips are quite tiny and the "tape method" says its aligned well with the hot spots at the extremes overlapping such that I can't tell how much they are off, if at all.

I just got an idea :eek:. I will have to test it this weekend if I can acquire something from work here.

John Lifer
04-21-2017, 4:39 PM
I'm not worried about it that much, You wouldn't do that! But ME on the other hand? 10pm, hurrying to get another tube up and running? Yep, hole right thru it. And the screw could be 10mm short and I'd still find a way to screw it up!!!!!
It sounds like you are putting the mount out for others to use, just close the hole on your 3D part and all is good! (yeah, you could find closed inserts, but not nearly as easy as thru threaded). And I thought it was a multi method of locking the screw.

Good job. It is different from what I've seen made up and actually works better. You have easy directional changes in both directions. And doing this way forces you to align better. ( at least in my opinion, you just can't drop onto a fixed base and bolt down as I did with mine and I DO have slight angled cut in the Y direction which makes me believe that the tube is not in same plane as the moving rail. I can't adjust the head on my machine, it has to be the tube. And I'm lazy)

Mike Audleman
04-21-2017, 5:25 PM
Of course its going to be posted for others to use. Why would I keep something like this hidden away :) I am not in this for anything but a hobby so I don't have any IP to protect. I expected to post it when I got it done from the get go. But I am not one to post unfinished or untested builds. If its in my thingiverse profile for download, you can bet I have printed, tested and likely used it or I don't post it. And if someone picks it up and improves it, then I get a better mount too :)

I haven't gotten to the point of verifying the squareness of the gantry yet. I will. Just now getting the machine to poke holes in something for the first time in 2 years. Baby steps :) And I wanted to get the mA meter installed as everyone agrees that this machine is likely overdriving the tube and I don't want to kill another one out of ignorance. Until I can place the meter inline, I am going to not go over 60% on the controller.

And the idea I had earlier is going to be possible to try, what I wanted we did have here at work. Have to try it first before I post what it is. Don't wanna look stupid if it doesn't work like I think it will.

Mike Lysov
04-23-2017, 9:22 PM
What an interesting idea for mounting a tube. Thanks for sharing. I'd wish I had them when was trying to align my tubes.

Now when I look at yours I have remembered something.
For those who does not have a 3D printer there are a product from astronomy field that can be used instead.
They are called guide scope mounting rings.
http://www.losmandy.com/hi-rez-images/DVR125.jpg

They are cheap, a lot of astronomy shops sell them and they come in different sizes.

Mike Audleman
04-24-2017, 10:40 AM
What an interesting idea for mounting a tube. Thanks for sharing. I'd wish I had them when was trying to align my tubes.

Now when I look at yours I have remembered something.
For those who does not have a 3D printer there are a product from astronomy field that can be used instead.
They are called guide scope mounting rings.
http://www.losmandy.com/hi-rez-images/DVR125.jpg

They are cheap, a lot of astronomy shops sell them and they come in different sizes.

I had looked at those too. The local science shop has them. However there are initial issues with it that i recognized right away.
1. It creates small pressure points on the glass tube which could potentially shatter it. They are designed for metal tube scopes, not thin glass tubes.
2. Adjusting the tube within the mount is another triangular movement. You do not get easy L-R and U-D adjustments. You must turn two screws to move the tube and this also moves it in both U-D and L-R directions. Same as the mirrors which I hate with a passion. And while adjusting those screws, see the caution of #1
3. They are designed to mount on a rail. So some additional mounting would be needed to use them as there is never a rail like that in our lasers.
4. Not overly cheap. The ones I saw (which were too large) were over $120 for a pair.

Yes. They might be useful if you take the precautions against damaging the glass tube. I don't know how fragile these tubes are. But I am not rolling the $150+ dice to find out.


Also, you don't need a 3D printer. Once I place it up on thingiverse, you can have places such as 3D hubs or Shapeways print it for you. Obviously there is a cost for that but its an option for those not owning a printer.

Matt McCoy
04-24-2017, 11:32 AM
Mike: This is a great thread and my cup of tea. Thanks for sharing.

Mike Audleman
04-26-2017, 10:57 AM
Mike: This is a great thread and my cup of tea. Thanks for sharing.

You are welcome. I will be doing the final prep and upload on the mount this weekend. Have had some other things I needed to work in this week after work.

It will be here: http://www.thingiverse.com/Wolfie/designs

Mike Audleman
05-09-2017, 3:00 PM
Been under the weather lately. Still not very chipper. However, I did get the mount posted to thingiverse and popped in here long enough to throw this post up.

The mount is available for anyone to download here:
http://www.thingiverse.com/thing:2305604

Mike Lysov
05-12-2017, 2:58 AM
Yes. They might be useful if you take the precautions against damaging the glass tube. I don't know how fragile these tubes are. But I am not rolling the $150+ dice to find out.

There are some that come with soft pads at the end of each bolt. Some telescopes can cost more than lasers and nobody wants to make even a tiny scratch on their paint :-) I think I may even have one set of this rings with soft pads but need to check as I have not touched my telescope for years.

Thanks for reminding me about 3d hubs, totally forgot about this way to print what you need without investing in a 3D printer.