I always used to make customised knobs in metal which had a knurled body with a piece of studding screwed and Loctited in place. It was good knurling practice and they looked fine until 3D printing came along.
I now have a variety of ‘styles’ for knob bodies modelled in Fusion 360. These have a hexagonal profile recess together with either a threaded hole or clearance hole modelled into them. A nut is Loctited onto the thread and then the thread with the nut in place SuperGlued into the 3D printed body.
As usual I’m all for an easy (a.k.a. lazy) way of doing things …. here is a Fusion image.
This concept was passed to me from a friend and is based on a design published by Ralph Patterson in 2007. The idea was to make a mounting block and extension arm in metal to allow a vernier to ‘stand up’ and be used vertically. My contact sent me the drawings. I don’t seem able to find any link to this or other files by Mr Patterson.
Entering the design into Fusion 360 did not take very long which indicates how well it was drawn originally by Mr Patterson. There was one major modification however. The original design was made from metal but our spin on it was to use 3D printed parts. The base would therefore not have any really mass to keep it stable. My friend suggested we added ballast in the form of lead shot into a cavity in the base. I reduced the height of the base print by 3mm to allow an aluminium plate to be fitted to the bottom and added a honeycomb of holes into the base. Once printed the honeycomb is filled with lead and the base screwed in place. Conveniently and by fluke rather than design, the honeycomb holes will hold two slightly squashed 0.22″ air gun pellets. This makes the base feel somewhat more solid on a surface plate.
The slot in the top of the base that takes the vernier is a tight fit on two of my verniers and the third one won’t fit so care is needed in choosing the right vernier for the job. That aside it works very well for a quick and dirty measurements.
If anyone would like the STL files then let me know on the blog email or post a comment.
Of late there has been a long thread running about Fogbuster use on the MEW forum. This set me thinking. The forum debate centred on whether mist lubricant or flood coolant was more or less healthy. For hobbyists the consensus seemed to favour the mist coolant. This was with the proviso that the jet and coolant mix is carefully balanced. An interesting point was made about ensuring the air stream was pointing away from the operator to avoid blowback. If all is good you should not be able to smell the lubricant. (N.B. I use QualiChem Xtreme Cut 250C at around 8% dilution).
The installation on my Tormach PCNC440 is fine with respect to blowback at the operator. Both nozzles are on flexible mountings and can be easily directed towards the back of the mill. (See prior post).
My installation just completed on my Myford Super 7 is not quite so perfect. I was using a T slot at the back of the saddle as the nozzle mounting. This meant the nozzle was playing on the back of the workpiece and towards the operator. Perhaps with hindsight not the most healthy option. OK so I don’t use lubricant on the lathe that much as most of my work is brass and aluminium so maybe less of a critical issue. Because of the infrequent use I wanted the Fogbuster to be quickly demountable until the next steel job comes along, hence the T slot idea.
I have a Myford Quick Change Toolpost fitted on the Super 7 which has two tool holder positions at right angles to each other. It struck me that the Fogbuster could be mounted in the QCTP unused slot. This would allow the air jet and lubricant to point forwards towards the workpiece. Normally I would have the empty slot on the far side face so a boring bar can be dropped into place. By rotating the QCTP through 180 degrees the spare slot would sit nearest the operator and be ideal for the Fogbuster.
I didn’t really want to dedicate a steel tool holder to the Fogbuster so I created a 3D printed version. This picked up on the prior mounting holes I had modelled in the flexible clamp.
I needed to make sure my 3D printed profile was a good fit in the QCTP so after fully modelling it I moved the time line in Fusion back to the profile extrude and reduced this from 26mm to 5mm and ran a test print on just a 5mm depth version. This allowed a quick print to be done which gave me feedback to do some minor edits. The timeline then was dragged fully forward and a full size print run. Try doing that as easily and quickly in steel ?
The pseudo toolholder 3D print ran in around 90 minutes and looked and fitted well. To finish off, I turned up a small clamping button to match the normal clamping and height adjustment screw on the QCTP.
Hey presto a new Fogbuster forward facing mounting ready to go.
Fogbuster mounting using the Myford QCTPOverview of Fogbuster mounting on a Myford QCTP
I have had my Sindoh 3D printer for quite a while and it is a lovely machine to use in conjunction with Fusion 360. I have printed all manner of items for the workshop, for projects and for friends and family.
For some time it has been a problem to print objects central on the bed. While they would print OK, they are reluctant to come away from the bed surface and then having removed them from the bed, the raft would be very reluctant to leave the printed object. I have got round this by offsetting the print position in X and Y on the table. If I have a large object to print that overlaps the problem area I sprinkle talcum powder on the bed surface to ease freeing the object from the bed but this does not help the raft removal.
The print bed is an aluminium sheet that slides in and out of the machine. This has a PTFE style laminated coating sheet held in place by adhesive. If I inspect the centre of the plate I can see the clear outline of bubbles under the lamination sheet. These have got worse as time has gone by. I imagine the bubbles create a finite air gap that upsets the temperature stability of the plate in the damaged area.
The situation had reached a frustrating peak today and lead to me totally removed the laminating sheet to leave bare aluminium. The printer could not cope with bare ally and the PLA would not stick. Some other laminating medium was going to be needed.
I had seen discussion regarding the use of what we in the UK call Masking Tape as a laminating medium. I use 3M Blue Multipurpose Builders Masking Tape for Super Glue mounting of stock on the milling machine. Having this to hand, I thought it worth a try. The tape is 48mm wide so I had to fix a number of strips across the plate to cover it completely and then trim the edges. As you can see below, I didn’t quite get them parallel and butted to each other I was keen to run a test print.
Maybe I was lucky but the job came off the tape easily and the raft pulled off straightaway with no damage to the print. The tape hasn’t bubbled or coming off in any way so it looks good.
3M Blue Builders Tape on my Sindoh print bed
I am not sure how long the tape is going to last but I have got a full reel to keep swapping it out.
Update : 17/6/2021
I have been using the blue tape bed coating for over a year now with no problems other than an occasional replacement when it gets torn.
The other thing worth noting is that if your bed clips break there is an excellent replacement print model to download here
I seem to have created a small demand at the local golf club for the simple golf scoring aid which I had designed and fitted to our electric trolleys. The design makes use of old thumbwheel switches which manufacturers don’t seem to use these days with the advent of electronically created equivalents.
Thumbwheels are cheap to buy on EBay and with the addition of a simple Fusion 360 designed and 3D printed block to mount them, they fit nicely on the side of the trolley scorecard holder accessory. The design uses two thumbwheels so the user can score their own and their partners score. Simple but very useful especially since I can’t remember what day it is never mind how many shots I have fluffed.
