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Well today I manage to finish tapping both top and bottom sets of securing bolts before making a fixture to cut the 16 or so bolts to same size. Once this was done it was over to the milling machine to firstly cut three slots before switching to the cutter to make the 'T' Slots. this is a messy job and certainly made my arm ache. I must get the power feed sorted out!

'T' slots mikked into the first part of the table top

I also forgot to change the speed of the milling machine and it didn't take long to for me to realise! So after changing the belts to get a much slower speed it all went well but I didn't feel up to continuing on with the long top plate. Hopefully next time it won't take too long to finish the slots. I will then make three supports from brass square bar so I can add a cover (steel) if I feel I need it.

Today was the first time that I could get back into the workshop for a while so I decided not to over stretch myself and just mill up the locating slots in the twp base and two top pieces.

To help speed up the process in setting up each piece I used the straight edge of the table to locate a strip of angle iron. This raised the edge up high enough so each piece rested against it and the aluminum then clamped in place. Now this is where the DRO’s (digital read out) came into there own since once I set the depth of cut and ‘Y’ axis (I set them both at zero) then it was simple to just unclamp and then replace a piece. The end results were certainly good enough for this application.

After trying the back plate into one slot, the width was adjusted then full steam ahead with an aching arm and back from all that handle turning! I have a 12v windscreen wiper motor waiting to set it up as a power feed but decided that if I went on to make that project to finish this one it would be even longer before I could get back to the pair of seal engines!

After checking that all four parts slotted into the back plate I marked out in the channels the position of holes for the securing screws. These were then countersunk before finishing for the day.

Hopefully the next session shall see me cut the ‘T’ slots in the top ready for any fixings and the uprights between the base and top cut and secured in place. This will certainly see the last phase of the project come into view at long last.

Overnight I considered how to make and fit a safety guard for the saw table project. So at breakfast time (0600) I took pencil and paper in hand and roughed out a design that I thought may work. When going out into the workshop my first task was to see what materials I had that could be used for the design.

So armed with some brass angle and sheet brass I started to mark out my design. I must admit it would have been easier if I had made the guard from stiff cardboard as I have done previously but for some reason I forgot to do this until I was a fair way through the making of the guard.

Fortunately the spare blades for the Proxxon bandsaw had arrived from Chronos and it was really nice to cut some brass sheeting with a new blade! It reminded me that the new saw table would be ok for some tasks relating to sheeting (differing materials) but I should forget my trusty Proxxon.

After making the brass back plate for the guard I fiddled for quite a while trying to work out how I could fit it without the guard fouling the blade. I wanted to offset the pivot point to clear the end of the saw pulley but the circle of movement was then moved. In the end I decided to adjust the slot in the top table to give me the clearance required. Simple to write but that was an hour or so gone!

To form the top of the guard I decided to use brass angle and to allow the curvature required I cut slits at ½” intervals using the bandsaw and then drilling holes in the centre of each newly formed tab.

I mulled over whether to silver solder, bolt or rivet the angle in place and in the end thought that copper rivets against a brass fitting would contrast nicely when it came time to add some ‘bling’. The brass angle was held in place with 4 equidistant temporary 4BA bolts whilst all the holes were drilled before the inside holes were countersunk so the copper would have somewhere to go. This will help the rivets hold the two parts together.

With the outer part of the guard in place the final slotting of the table top could be done and a piece of brass angle was used to form the pivot bracket. it is secured to the underside of the table top which is where I got to at the end of the session. However I may have another problem to overcome since I made sure the work was done when the largest saw blade is at its highest position. When reflecting on what needed to be done next time I thought that the system may not work! When the saw blade is lowered the guard does not go with it!

My initial reaction is that the guard will still serve its purpose if it sits above the blade but just on the edge so that when it is lowered it does not foul. If that isn’t a solution then I will have to rethink how the guard can be secured to the saw pivot arm. And that would be a problem!

The guard will be held in position by a spring once I have the system sorted out. Again, don’t take too much notice of the finish of the parts since it will be dismantled when finished and ‘blinged’ up then…….

Rivets being used to secure the brass angle that forms the top of the guard

The brass angle being formed around the template

Trying the template to see how to fix it in place

The overall circumference was cut out using the Proxxon Bandsaw

I managed to scrounge an aluminium piston from a local marine engineer (he repaired our boat engine......) and intend to see if I can produce the pistons for the Seal engines from it. I am working on the premise that if its good enough for full sized engines then it will be good enough for the smaller scale Seal.

I am hoping to get all 8 pistons from it but until I cut it up and see how much 'meat' there is in each segment I won't know. Still nothing ventured as they say........come back and see how I get on..

A short session today in the workshop and I didn’t feel up to doing anything major or critical. Overnight I had been thinking about the saw table project and a moment of possible inspiration came when I wondered what a normal slitting saw would be like in use on the saw table?

When I had a look at the saw pulley it was turned to 1” diameter and of course the slitting saws I have are 1” bore! So I decided to spend my time working out how to fit the slitting saw to the existing pulley rather than turn another (I also didn’t have another bearing). The answer I thought of was to make a washer that would seat against the pulley and have a large 1 ¼” diameter outside.

So it was over to the lathe and turn the required washer (see photo) and then see if it worked. I also needed to have a larger washer to sit in front of the slitting saw so I could use the same securing nut.

The adaptor washer to enable slitting saws also to be used

I was really surprised when trying the saw out with some brass sheet just how good it was! Now you may have been ahead of me but for sheet work I believe the saw table will be a great asset (for straight cuts only) and a real bonus for the project!

I also had a fiddle with some of the pulleys to get them running for a long period and called it a day surprised with the advance in usability of the project which is already good. Next will be to try the diamond grindstone and what sort of fittings I will need to make to grind turning tools. Once this trial period has been completed I will fit the top and bottom sheets to the back plate and securing everything together.

For the work holding I intend to cut either two or three ‘T’ slots along the top table. After making a couple of basic work holding tools I will put the project to one side and get back to building the Seal engines. When I need to use the table I will develop tooling each time to suit the task and over time this should build up a flexible system.

Components to allow a slitting saw to be used with the table

HSS Slitting Saw 5 x 1 4 x 1

£15.24

1h 8m

Over the last couple of sessions I have made some progress on the saw table project. Today I completed the quadrant for the saw height adjustment and assembled all the parts to date. I decided that the next job would be to give the back plate a little ‘clean up’ and used a wire brush in the milling machine to polish off the marks that naturally occur when making an item.

Now that the mechanism was complete it allowed me to make up the drive belt which I found more difficult than expected. I tried out the process on a couple of scrap pieces and simply melting the ends produced all sorts of results. After some practice I managed a reasonable result that allowed me to make a good joint on the proper belt.

When running the system for the first time I was pleased that all turned as expected and the drive from the belt worked with varying tension settings. After 30 seconds or so the whole thing stopped dead. The pulley that holds the gear wheel on has seized up. On investigation the bolt holding the pulley on had tightened itself up sufficiently enough to stop it. The design was not meant to rely on any securing method to impact on the pulley turning. I had turned the shaft so that it extended beyond the brass pulley and in theory it should have worked. When looking at the problem further I thought that perhaps I had not left enough showing and all sorts of ideas came to mind particularly taking some of the pulley width off.

However the answer was simply to change the washer on the end of the shaft from one that covered the whole bearing to a much smaller one that only covered the end of the inner shaft. This cured the problem so the motor was started again and run for a couple of minutes before the saw blade stopped again. This time it was the pulley that holds the saw blade that had seized. Looking closely it was the shaft that was binding and I simply took a couple of thou off the end of the shaft being careful not to reduce the shaft part that the bearing sat on.

The motor was started again and all ran as it should do. I then varied the height of the blade to the two extremes and tensioned the belt to suit. All ran well and I will now be able to cut the studding used for the blade adjustment.

Suitable pleased I thought I would make a start on the top plate and soon produced the first part of the top with the slot for the diamond grit and two sizes of saw blade to fit in. This was placed in situ and I thought I would just ‘try’ the blade to see how it would cut. I am glad I did since I will have to ensure that any clamping system will take into account the kick back effect found when cutting some brass sheet. I then tried a ¼” diameter steel bar and you can see the results in the pictures. It wasn’t really a proper test since the bar wasn’t held properly but it actually cut better then the brass sheet. I have no doubt about the blades ability to cut. Then I tried the end of the HT steel that bar that started the whole project and was really pleased to see the small cut that appeared in the end of the bar! It will cut it and that’s good news.

So today’s session really is the beginning of the end…………………………………..watch this space.

Today I managed to make the basics for the mechanism to adjust the blade/grinding wheel height. It consists of a bracket with a slot in it that holds the brass adjusting wheel. This bracket will be secured to the back plate of the saw table and because the wheel is trapped between the forks of the bracket by turning the knurled wheel the studding will advance or retract accordingly.

What remains to be sorted out is a linkage between the end of the studding and the fulcrum lever.

Since the fulcrum lever moves at an angle to the vertical position, this will not allow a direct fixing method to the studding. So either I make a pin in the upright with a slot in the fulcrum arm allowing the pin to slide, or a linkage not locked at either end, has yet to be decided. I will make up some drawings tonight (as per last nights bracket design) before making up the part(s) in the next session.

Ignore the finish as the 'bling' will be added when the saw table is completed.

Today was another short session but at least it was a session! I continued to work on the handle assembly for the belt tensioning system.

After turning down the brass for the main part (it’s the nicest cutting brass I have ever used) the centre was centre drilled, drilled and tapped to suit the studding. I am not impressed with one aspect of my design however and will decide on whether to amend it now or see how the whole assembly pans out.

I have thought of a solution to the problem but may wait to implement it. The design fault centers on the handle which moves away from the saw table when in use. My solution will be to make a fork which then fits into a grove that will need to be cut on the handle boss and the fork secured to the saw table. That would allow the handle to stay in place and the studding would pass through its centre.

I did consider remaking the brass block which moves in the slide and holds the pulley, but the studding would need to pass through it instead. I prefer the fork option at the moment but will see how it all works in operation before making a decision. The next piece made today was the handle and I decided to make it from aluminum as a contrast to the brass and turned a taper towards the handle.

This was then clearance drilled to suit a 6mm bolt. The final task was to drill and tap a hole for a grub screw in the boss which will secure the handle assembly on the studding. That completed the handle.

The next session will focus on making the assembly to adjust the height of the saw blade. I may use a similar set up to the belt tensioning system but will think about it overnight. If you would like to see a larger picture just click on the one your interested in.

After silver soldering the three pins for the Fowler traction engine (plans and castings by MJ Engineering) together yesterday I managed to clean them up this morning. If you read my previous post you will know I was not impressed with my work which normally goes well. I put this down to either or both the new flux and the new stick of silver solder. I fully expected the parts to fall apart and a lengthy cleaning up or even making new parts to be required, but the solder did flow in the right places!

Three pins for the Fowler A7 Traction Engine

After a clean up and close inspection I would say they are well and truly brazed together but the process was not as satisfying as the end result. Unusual I know. I still need to work out, perhaps using some test pieces, why things did not go as well as previous silver soldering but at least the pins were ok.